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  • 251.
    Satula, Wojciech
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Wyss, Ramon
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Rafalski, Michal
    Global properties of the Skyrme-force-induced nuclear symmetry energy2006In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 74, no 1, p. 011301-Article in journal (Refereed)
    Abstract [en]

    A novel concept for the nuclear symmetry energy (NSE) is corroborated by large scale calculations. The paper firmly demonstrates that within the local density approximation, the value of the NSE coefficient, a(sym)(A), depends on two basic ingredients: the mean-level spacing, epsilon(A), and the effective strength of the isovector mean-potential, kappa(A). Surprisingly, our results reveal that these two basic ingredients of a(sym) are almost equal after rescaling them linearly by the isoscalar and the isovector effective masses, respectively. This result points towards a hidden and hitherto unresolved fundamental property of the effective nuclear interaction. In addition, our analysis yields naturally the ratio of the surface-to-volume contributions to a(sym) with a value of similar to 1.6, consistent with hydrodynamical estimates for the static dipole polarizability as well as the neutron-skin. Although the present study is restricted to energy density functionals obtained from Skyrme forces the method is general and can easily be applied to more general local energy density functionals and nonnuclear bifermionic systems.

  • 252.
    Satula, Wojtek
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Wyss, Ramon
    Mean-field description of high-spin states2005In: Reports on progress in physics (Print), ISSN 0034-4885, E-ISSN 1361-6633, Vol. 68, no 1, p. 131-200Article, review/survey (Refereed)
    Abstract [en]

    Recent high-spin observations reveal entirely new modes of collective rotational motion and the existence of novel symmetries and spontaneous symmetry breaking phenomena, uncovering hitherto unexploited coupling schemes of intrinsic and collective degrees of freedom. It continues to stimulate the theoretical progress in the field, which clearly turns towards a microscopic description based on self-consistent approaches using either an effective non-relativistic Hamiltonian or an effective relativistic Lagrangian. New coupling schemes call not only for symmetry unrestricted mean-field theories, but also for extensions going beyond the mean-field. The progress in the development of these theoretical methods is discussed in this review.

  • 253.
    Satula, Wojtek
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Wyss, Ramon
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Rafalski, M.
    Cranking in isospace - Applications to neutron-proton pairing and the nuclear symmetry energy2005In: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 25, no SUPPL. 1, p. 559-562Article in journal (Refereed)
    Abstract [en]

    Isoscalar pairing interaction and nuclear symmetry energy are investigated by means of the iso-cranking technique. Iso-cranking represents the lowest order approximation to isospin projection after variation. Due to its internal simplicity, it offers a very intuitive understanding of the structure of the nuclear symmetry energy as well as the response of the isoscalar and isovector pairing versus isospin.

  • 254.
    Satula, Wojtek
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Wyss, Ramon
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Zalewski, M.
    Contradicting effective mass scalings in the single-particle spectra calculated using the Skyrme energy density functional method2008In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 78, no 1, p. 011302-Article in journal (Refereed)
    Abstract [en]

    The problem of the effective mass scaling in the single-particle (s.p.) spectra calculated within the Skyrme energy density functional (EDF) method is studied. It is demonstrated that for specific pairs of orbitals like 1d(3/2)-1f(7/2) the commonly anticipated isoscalar effective mass (m*) scaling of the s.p. level splittings is almost canceled by an implicit m* scaling present in the two-body spin-orbit (SO) strength. On the other hand, the nu f(7/2)-nu f(5/2) SO splitting depends solely on the SO strength. Hence, two conflicting scaling properties appear to be at work in standard Skyrme EDF, making the theory internally inconsistent with respect to s.p. energies. It is argued that this unphysical property is, to a large extent, a consequence of the strategies and data sets used to fit these functionals. The inclusion of certain s.p. spin-orbit splittings to fit the two-body spin-orbit and the tensor interaction strengths reinstates the conventional m* scaling and improves the performance of the Skyrme EDF.

  • 255.
    Satula, Wojtek
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Wyss, Ramon
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Zdunczuk, H.
    Using high-spin data to constrain spin-orbit term and spin-fields of Skyrme forces - The need to unify the tune-odd part of the local energy density functional2005In: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 25, no Suppl. 1, p. 551-552Article in journal (Refereed)
    Abstract [en]

    A method to study spin-fields and the spin-orbit potential within the local energy density approach is presented. The concept utilizes the intrinsic simplicity of terminating states in order to constrain certain parameters of the local nuclear energy functional. In particular, constraints on the isoscalar Landau parameter go and the strength of the spin-orbit potential are thoroughly discussed.

  • 256.
    Satula, Wojtek
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Zalewski, M.
    Dobaczewski, J.
    Olbratowski, P.
    Rafalski, M.
    Werner, T. R.
    Wyss, Ramon A.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    GLOBAL NUCLEAR STRUCTURE ASPECTS OF TENSOR INTERACTION2009In: International Journal of Modern Physics E, ISSN 0218-3013, Vol. 18, no 4, p. 808-815Article in journal (Refereed)
    Abstract [en]

    A direct fit of the isoscalar spin-orbit and both isoscalar and isovector tensor coupling constants to the f(5/2) - f(7/2) SO splittings in Ca-40, Ni-56, and Ca-48 requires (i) a significant reduction of the standard isoscalar spin-orbit strength and (ii) strong attractive tensor coupling constants. The aim of this paper is to address the consequences of these strong attractive tensor and weak spin-orbit fields on total binding energies, two-neutron separation energies and nuclear deformability.

  • 257. Saygi, B.
    et al.
    Joss, D. T.
    Page, R. D.
    Grahn, T.
    Simpson, J.
    O'Donnell, D.
    Alharshan, G.
    Auranen, K.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Boening, S.
    Braunroth, T.
    Carroll, R. J.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Cullen, D. M.
    Dewald, A.
    Doncel, M.
    Donosa, L.
    Drummond, M. C.
    Ertugral, F.
    Erturk, S.
    Fransen, C.
    Greenlees, P. T.
    Hackstein, M.
    Hauschild, K.
    Herzan, A.
    Jakobsson, U
    KTH.
    Jones, P. M.
    Julin, R.
    Juutinen, S.
    Konki, J.
    Kroell, T.
    Labiche, M.
    Lopez-Martens, A.
    McPeake, C. G.
    Moradi, F.
    Moeller, O.
    Mustafa, M.
    Nieminen, P.
    Pakarinen, J.
    Partanen, J.
    Peura, P.
    Procter, M.
    Rahkila, P.
    Rother, W.
    Ruotsalainen, P.
    Sandzelius, M.
    Saren, J.
    Scholey, C.
    Sorri, J.
    Stolze, S.
    Taylor, M. J.
    Thornthwaite, A.
    Uusitalo, J.
    Reduced transition probabilities along the yrast line in W-1662017In: Physical Review C: Covering Nuclear Physics, ISSN 2469-9985, E-ISSN 2469-9993, Vol. 96, no 2, article id 021301Article in journal (Refereed)
    Abstract [en]

    Lifetimes of excited states in the yrast band of the neutron-deficient nuclide W-166 have been measured utilizing the DPUNS plunger device at the target position of the JUROGAM II gamma-ray spectrometer in conjunction with the RITU gas-filled separator and the GREAT focal-plane spectrometer. Excited states in W-166 were populated in the Mo-92(Kr-78, 4p) reaction at a bombarding energy of 380 MeV. The measurements reveal a low value for the ratio of reduced transitions probabilities for the lowest-lying transitions B(E2; 4(+)-> 2(+)) / B(E2; 2(+)-> 0(+)) = 0.33(5), compared with the expected ratio for an axially deformed rotor (B-4/2 = 1.43).

  • 258. Schef, P
    et al.
    Lundin, P
    Biémont, E
    Källberg, A
    Norlin, Lars-Olov
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Palmeri, P
    Royen, P
    Simonsson, A
    Mannervik, S
    Disentanglement of magnetic field mixing reveals the spontaneous M2 decay rate for a metastable level in Xe+2005In: Physical Review A. Atomic, Molecular, and Optical Physics, ISSN 1050-2947, E-ISSN 1094-1622, Vol. 72, no 2, p. 020501-Article in journal (Refereed)
    Abstract [en]

    We have investigated the radiative decay of the metastable level 5d(4)D(7/2) in Xe+. Theoretically we find the decay to be heavily dominated by an M2 transition and not by M1/E2 transitions. Lifetime measurements of 5d(4)D(7/2) in a storage ring are difficult since magnetic mixing of the metastable with a short-lived level quenches its population. Decay rates were determined at different magnetic field strengths (B) in order to allow a nonlinear extrapolation to B=0. The experimental lifetime of 2.4 +/- 0.8 s was in agreement with the calculated value, but much smaller than previously estimated.

  • 259. Scholey, C.
    et al.
    Andgren, Karin
    KTH, School of Engineering Sciences (SCI), Physics.
    Bianco, L.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Darby, I. G.
    et al,
    Isomeric and ground-state properties of Pt-171(78), Os-167(76), and W-163(74)2010In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 81, no 1Article in journal (Refereed)
    Abstract [en]

    Decay paths, half-lives, and excitation energies of the i(13/2) bandheads of the neutron-deficient nuclei Pt-171, Os-167, and W-163 have been established for the first time. Gamma-ray transitions, X-rays, and internal conversion electrons have been observed, allowing internal-conversion coefficients to be measured and B(M2) reduced transition probabilities to be extracted. These results elucidate the low-lying single-quasiparticle structures and give the energy level spacings between the nu f(7/2), nu h(9/2), and nu i(13/2) quasineutron states for all three nuclei. Moreover, ground-state spin assignments have been made for the first time, along with the measurement of the alpha-decay branching ratio for Pt-171. The decay paths of the i(13/2) bandheads were followed by favored alpha decays, indicating that all three nuclei have the same I-pi = 7/2(-) ground state.

  • 260. Scholey, C.
    et al.
    Sandzelius, Mikael
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Eeckhaudt, S.
    Grahn, T.
    Greenlees, P. T.
    Jones, P.
    Julin, R.
    Juutinen, S.
    Leino, M.
    Leppanen, A. P.
    Nieminen, P.
    Nyman, M.
    Perkowski, J.
    Pakarinen, J.
    Rahkila, P.
    Rahkila, P. M.
    Uusitalo, J.
    Van de Vel, K.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Hadinia, Baharak
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Lagergren, Karin
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Joss, D. T.
    Appelbe, D. E.
    Barton, C. J.
    Simpson, J.
    Warner, D. D.
    Darby, I. G.
    Page, R. D.
    Paul, E. S.
    Wiseman, D.
    In-beam and decay spectroscopy of very neutron deficient iridium nuclei2005In: Journal of Physics G: Nuclear and Particle Physics, ISSN 0954-3899, E-ISSN 1361-6471, Vol. 31, no 10, p. S1719-S1722Article in journal (Refereed)
    Abstract [en]

    Iridium nuclei at and beyond the proton drip line have been studied via fusion evaporation reactions. A reaction of Mo-92(Kr-78, p2n) at a beam energy of 360 MeV and target thickness 500 mu g cm(-2) was employed to study (167,167m) Ir. A reaction of Sn-112(Ni-58, p2n) at a beam energy of 266 MeV and target thickness 500 mu g cm(-2) was used to study (169,169m) Ir. The experiments were performed at the University of Jyvaskyla utilizing the RITU separator in conjunction with the focal plane GREAT spectrometer and the JUROGAM Ge array at the target position. Excited states feeding. both the ground state and isomeric state in Ir-169, excited states feeding the ground state of Ir-167 and the ground state alpha decay of Re-165 have been observed for the first time along with excited states feeding (167)m Ir Experimental spectroscopic factors and reduced widths have been obtained for the proton and alpha decay of these nuclei.

  • 261. Senyigit, M.
    et al.
    Ataç, Ayşe
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Akkoyun, S.
    Kaskas, A.
    Bazzacco, D.
    Nyberg, J.
    Recchia, F.
    Brambilla, S.
    Camera, F.
    Crespi, F. C. L.
    Farnea, E.
    Giaz, A.
    Gottardo, A.
    Kempley, R.
    Ljungvall, J.
    Mengoni, D.
    Michelagnoli, C.
    Million, B.
    Palacz, M.
    Pellegri, L.
    Riboldi, S.
    Sahin, E.
    Soderstrom, P. A.
    Dobon, J. J. Valiente
    Identification and rejection of scattered neutrons in AGATA2014In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 735, p. 267-276Article in journal (Refereed)
    Abstract [en]

    gamma Rays and neutrons, emitted following spontaneous fission of Cf-252, were measured in an AGATA experiment performed at INFN Laboratori Nazionali di Legnaro in Italy. The setup consisted of four AGATA triple cluster detectors (12 36 fold segmented high purity germanium crystals), placed at a distance of 50 cm from the source, and 16 HELENA BaF2 detectors. The aim of the experiment was to study the interaction of neutrons in the segmented high purity germanium detectors of AGATA and to investigate the possibility to discriminate neutrons and gamma rays with the gamma-ray tracking technique. The BaF2 detectors were used for a time measurement, which gave an independent discrimination of neutrons and gamma rays and which was used to optimise the gamma-ray tracking based neutron rejection methods. It was found that standard gamma-ray tracking, without any additional neutron rejection features, eliminates effectively most of the interaction points clue to recoiling Ge nuclei after elastic scattering of neutrons. Standard Cracking rejects also a significant amount of the events due to inelastic scattering of neutrons in the germanium crystals. Further enhancements of the neutron rejection was obtained by setting conditions on the following quantities, which were evaluated for each event by the Cracking algorithm: energy of the first and second interaction point, difference in the calculated incoming direction of the gamma ray, and figure-of-merit value. The experimental results of Cracking with neutron rejection agree rather well with GEANT4 simulations.

  • 262. Shen, S. F.
    et al.
    Zheng, S. J.
    Xu, F. R.
    Wyss, Ramon A
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Stability of triaxial shapes in ground and excited states of even-even nuclei in the A similar to 70 region2011In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 84, no 4, p. 044315-Article in journal (Refereed)
    Abstract [en]

    Total-Routhian-surface calculations by means of the pairing-deformation-frequency self-consistent cranked shell model have been carried out for even-even germanium and selenium isotopes to search for possible stable triaxial deformations of nuclear states. The maximum triaxiality of |gamma| approximate to 30 degrees. is found in the ground and excited rotational states of the nuclei (64,74)Ge. The calculations are compared with available experimental data, giving a general agreement with observed triaxiality in the isotopes.

  • 263. Singh, B.
    et al.
    Erni, W.
    Krusche, B.
    Steinacher, M.
    Walford, N.
    Liu, H.
    Liu, Z.
    Liu, B.
    Shen, X.
    Wang, C.
    Zhao, J.
    Albrecht, M.
    Erlen, T.
    Fink, M.
    Heinsius, F. H.
    Held, T.
    Holtmann, T.
    Jasper, S.
    Keshk, I.
    Koch, H.
    Kopf, B.
    Kuhlmann, M.
    Kuemmel, M.
    Leiber, S.
    Mikirtychyants, M.
    Musiol, P.
    Mustafa, A.
    Pelizaeus, M.
    Pychy, J.
    Richter, M.
    Schnier, C.
    Schroeder, T.
    Sowa, C.
    Steinke, M.
    Triffterer, T.
    Wiedner, U.
    Ball, M.
    Beck, R.
    Hammann, C.
    Ketzer, B.
    Kube, M.
    Mahlberg, P.
    Rossbach, M.
    Schmidt, C.
    Schmitz, R.
    Thoma, U.
    Urban, M.
    Walther, D.
    Wendel, C.
    Wilson, A.
    Bianconi, A.
    Bragadireanu, M.
    Caprini, M.
    Pantea, D.
    Patel, B.
    Czyzycki, W.
    Domagala, M.
    Filo, G.
    Jaworowski, J.
    Krawczyk, M.
    Lisowski, E.
    Lisowski, F.
    Michalek, M.
    Poznanski, P.
    Plazek, J.
    Korcyl, K.
    Kozela, A.
    Kulessa, P.
    Lebiedowicz, P.
    Pysz, K.
    Schaefer, W.
    Szczurek, A.
    Fiutowski, T.
    Idzik, M.
    Mindur, B.
    Przyborowski, D.
    Swientek, K.
    Biernat, J.
    Kamys, B.
    Kistryn, S.
    Korcyl, G.
    Krzemien, W.
    Magiera, A.
    Moskal, P.
    Pyszniak, A.
    Rudy, Z.
    Salabura, P.
    Smyrski, J.
    Strzempek, P.
    Wronska, A.
    Augustin, I.
    Boehm, R.
    Lehmann, I.
    Marinescu, D. Nicmorus
    Schmitt, L.
    Varentsov, V.
    Al-Turany, M.
    Belias, A.
    Deppe, H.
    Veis, N. Divani
    Dzhygadlo, R.
    Ehret, A.
    Flemming, H.
    Gerhardt, A.
    Goetzen, K.
    Gromliuk, A.
    Gruber, L.
    Karabowicz, R.
    Kliemt, R.
    Krebs, M.
    Kurilla, U.
    Lehmann, D.
    Loechner, S.
    Luehning, J.
    Lynen, U.
    Orth, H.
    Patsyuk, M.
    Peters, K.
    Saito, T.
    Schepers, G.
    Schmidt, C. J.
    Schwarz, C.
    Schwiening, J.
    Taeschner, A.
    Traxler, M.
    Ugur, C.
    Voss, B.
    Wieczorek, P.
    Wilms, A.
    Zuehlsdorf, M.
    Abazov, V.
    Alexeev, G.
    Arefiev, V. A.
    Astakhov, V.
    Barabanov, M. Yu.
    Batyunya, B. V.
    Davydov, Y.
    Dodokhov, V. Kh.
    Efremov, A.
    Fechtchenko, A.
    Fedunov, A. G.
    Galoyan, A.
    Grigoryan, S.
    Koshurnikov, E. K.
    Lobanov, Y. Yu.
    Lobanov, V. I.
    Makarov, A. F.
    Malinina, L. V.
    Malyshev, V.
    Olshevskiy, A. G.
    Perevalova, E.
    Piskun, A. A.
    Pocheptsov, T.
    Pontecorvo, G.
    Rodionov, V.
    Rogov, Y.
    Salmin, R.
    Samartsev, A.
    Sapozhnikov, M. G.
    Shabratova, G.
    Skachkov, N. B.
    Skachkova, A. N.
    Strokovsky, E. A.
    Suleimanov, M.
    Teshev, R.
    Tokmenin, V.
    Uzhinsky, V.
    Vodopianov, A.
    Zaporozhets, S. A.
    Zhuravlev, N. I.
    Zinchenko, A.
    Zorin, A. G.
    Branford, D.
    Glazier, D.
    Watts, D.
    Boehm, M.
    Britting, A.
    Eyrich, W.
    Lehmann, A.
    Pfaffinger, M.
    Uhlig, F.
    Dobbs, S.
    Seth, K.
    Tomaradze, A.
    Xiao, T.
    Bettoni, D.
    Carassiti, V.
    Ramusino, A. Cotta
    Dalpiaz, P.
    Drago, A.
    Fioravanti, E.
    Garzia, I.
    Savrie, M.
    Akishina, V.
    Kisel, I.
    Kozlov, G.
    Pugach, M.
    Zyzak, M.
    Gianotti, P.
    Guaraldo, C.
    Lucherini, V.
    Bersani, A.
    Bracco, G.
    Macri, M.
    Parodi, R. F.
    Biguenko, K.
    Brinkmann, K. T.
    Di Pietro, V.
    Diehl, S.
    Dormenev, V.
    Drexler, P.
    Doern, M.
    Etzelmller, E.
    Galuska, M.
    Gutz, E.
    Hahn, C.
    Hayrapetyan, A.
    Kesselkaul, M.
    Koehn, W.
    Kuske, T.
    Lange, J. S.
    Liang, Y.
    Metag, V.
    Moritz, M.
    Nanova, M.
    Nazarenko, S.
    Novotny, R.
    Quagli, T.
    Reiter, S.
    Riccardi, A.
    Rieke, J.
    Rosenbaum, C.
    Schmidt, M.
    Schnell, R.
    Stenzel, H.
    Thoering, U.
    Ullrich, T.
    Wagner, M. N.
    Wasem, T.
    Wohlfahrt, B.
    Zaunick, H. G.
    Tomasi-Gustafsson, E.
    Ireland, D.
    Rosner, G.
    Seitz, B.
    Deepak, P. N.
    Kulkarni, A.
    Apostolou, A.
    Babai, M.
    Kavatsyuk, M.
    Lemmens, P. J.
    Lindemulder, M.
    Loehner, H.
    Messchendorp, J.
    Schakel, P.
    Smit, H.
    Tiemens, M.
    Van derweele, J. C.
    Veenstra, R.
    Vejdani, S.
    Dutta, K.
    Kalita, K.
    Kumar, A.
    Roy, A.
    Sohlbach, H.
    Bai, M.
    Bianchi, L.
    Buescher, M.
    Cao, L.
    Cebulla, A.
    Dosdall, R.
    Gillitzer, A.
    Goldenbaum, F.
    Grunwald, D.
    Herten, A.
    Hu, Q.
    Kemmerling, G.
    Kleines, H.
    Lai, A.
    Lehrach, A.
    Nellen, R.
    Ohm, H.
    Orfanitski, S.
    Prasuhn, D.
    Prencipe, E.
    Puetz, J.
    Ritman, J.
    Schadmand, S.
    Sefzick, T.
    Serdyuk, V.
    Sterzenbach, G.
    Stockmanns, T.
    Wintz, P.
    Wuestner, P.
    Xu, H.
    Zambanini, A.
    Li, S.
    Li, Z.
    Sun, Z.
    Rigato, V.
    Isaksson, L.
    Achenbach, P.
    Corell, O.
    Denig, A.
    Distler, M.
    Hoek, M.
    Karavdina, A.
    Lauth, W.
    Merkel, H.
    Mueller, U.
    Pochodzalla, J.
    Sanchez, S.
    Schlimme, S.
    Sfienti, C.
    Thiel, M.
    Ahmadi, H.
    Ahmed, S.
    Bleser, S.
    Capozza, L.
    Cardinali, M.
    Dbeyssi, A.
    Deiseroth, M.
    Feldbauer, F.
    Fritsch, M.
    Froerllich, B.
    Kang, D.
    Khaneft, D.
    Klasen, R.
    Leithoff, H. H.
    Lin, D.
    Maas, F.
    Maldaner, S.
    Martinez, M.
    Michel, M.
    Mora Esp, M. C.
    Morales, C. Morales
    Motzko, C.
    Nerling, F.
    Noll, O.
    Pfloeger, S.
    Pitka, A.
    Pineiro, D. Rodriguez
    Sanchez-Lorente, A.
    Steinen, M.
    Valente, R.
    Weber, T.
    Zambrana, M.
    Zimmermann, I.
    Fedorov, A.
    Korjik, M.
    Missevitch, O.
    Boukharov, A.
    Malyshev, O.
    Marishev, I.
    Balanutsa, V.
    Balanutsa, P.
    Chernetsky, V.
    Demekhin, A.
    Dolgolenko, A.
    Fedorets, P.
    Gerasimov, A.
    Goryachev, V.
    Chandratre, V.
    Datar, V.
    Dutta, D.
    Jha, V.
    Kumawat, H.
    Mohanty, A. K.
    Parmar, A.
    Roy, B.
    Sonika, G.
    Fritzsch, C.
    Grieser, S.
    Hergemoeller, A. K.
    Hetz, B.
    Huesken, N.
    Khoukaz, A.
    Wessels, J. P.
    Khosonthongkee, K.
    Kobdaj, C.
    Limphirat, A.
    Srisawad, P.
    Yan, Y.
    Barnyakov, A. Yu.
    Barnyakov, M.
    Beloborodov, K.
    Blinov, V. E.
    Bobrovnikov, V. S.
    Kuyanov, I. A.
    Martin, K.
    Onuchin, A. P.
    Serednyakov, S.
    Sokolov, A.
    Tikhonov, Y.
    Blinov, A. E.
    Kononov, S.
    Kravchenko, E. A.
    Atomssa, E.
    Kunne, R.
    Ma, B.
    Marchand, D.
    Ramstein, B.
    van de Wiele, J.
    Wang, Y.
    Boca, G.
    Costanza, S.
    Genova, P.
    Montagna, P.
    Rotondi, A.
    Abramov, V.
    Belikov, N.
    Bukreeva, S.
    Davidenko, A.
    Derevschikov, A.
    Goncharenko, Y.
    Grishin, V.
    Kachanov, V.
    Kormilitsin, V.
    Levin, A.
    Melnik, Y.
    Minaev, N.
    Mochalov, V.
    Morozov, D.
    Nogach, L.
    Poslavskiy, S.
    Ryazantsev, A.
    Ryzhikov, S.
    Semenov, P.
    Shein, I.
    Uzunian, A.
    Vasiliev, A.
    Yakutin, A.
    Roy, U.
    Yabsley, B.
    Belostotski, S.
    Gavrilov, G.
    Izotov, A.
    Manaenkov, S.
    Miklukho, O.
    Veretennikov, D.
    Zhdanov, A.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Makonyi, K.
    Preston, M.
    Tegner, P. E.
    Woelbing, D.
    Rai, A. K.
    Godre, S.
    Calvo, D.
    Coli, S.
    De Remigis, P.
    Filippi, A.
    Giraudo, G.
    Lusso, S.
    Mazza, G.
    Mignone, M.
    Rivetti, A.
    Wheadon, R.
    Amoroso, A.
    Bussa, M. P.
    Busso, L.
    De Mori, F.
    Destefanis, M.
    Fava, L.
    Ferrero, L.
    Greco, M.
    Hu, J.
    Lavezzi, L.
    Maggiora, M.
    Maniscalco, G.
    Marcello, S.
    Sosio, S.
    Spataro, S.
    Balestra, F.
    Iazzi, F.
    Introzzi, R.
    Lavagno, A.
    Olave, J.
    Birsa, R.
    Bradamante, F.
    Bressan, A.
    Martin, A.
    Calen, H.
    Andersson, W. Ikegami
    Johansson, T.
    Kupsc, A.
    Marciniewski, P.
    Papenbrock, M.
    Pettersson, J.
    Schoenning, K.
    Wolke, M.
    Galnander, B.
    Diaz, J.
    Chackara, V. Pothodi
    Chlopik, A.
    Kesik, G.
    Melnychuk, D.
    Slowinski, B.
    Trzcinski, A.
    Wojciechowski, M.
    Wronka, S.
    Zwieglinski, B.
    Buehler, P.
    Marton, J.
    Steinschaden, D.
    Suzuki, K.
    Widmann, E.
    Zmeskal, J.
    Semenov-Tian-Shansky, K. M.
    Feasibility study for the measurement of pi N transition distribution amplitudes at (P)over-barANDA in (P)over-barp -> J/psi pi(0)2017In: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 95, no 3, article id 032003Article in journal (Refereed)
    Abstract [en]

    The exclusive charmonium production process in (P) over barp annihilation with an associated pi 0 meson (p) over barp -> J/psi pi(0) is studied in the framework of QCD collinear factorization. The feasibility of measuring this reaction through the J/psi -> e(+) e(-) decay channel with the AntiProton ANnihilation at DArmstadt ((P) over bar ANDA) experiment is investigated. Simulations on signal reconstruction efficiency as well as the background rejection from various sources including the (P) over barp -> pi(+)pi(-)pi(0) and (p) over barp -> J/psi pi(0)pi(0) reactions are performed with PANDAROOT, the simulation and analysis software framework of the (P) over bar ANDA experiment. It is shown that the measurement can be done at (P) over bar ANDA with significant constraining power under the assumption of an integrated luminosity attainable in four to five months of data taking at the maximum design luminosity.

  • 264. Singh, B. P.
    et al.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Semenov-Tian-Shansky, T.
    et al.,
    Experimental access to Transition Distribution Amplitudes with the PANDA experiment at FAIR2015In: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 51, no 8, article id 107Article in journal (Refereed)
    Abstract [en]

    Baryon-to-meson Transition Distribution Amplitudes (TDAs) encoding valuable new information on hadron structure appear as building blocks in the collinear factorized description for several types of hard exclusive reactions. In this paper, we address the possibility of accessing nucleon-to-pion (pi N) TDAs from (p) over barp -> e(+)e(-)pi(0) reaction with the future PANDA detector at the FAIR facility. At high center-of-mass energy and high invariant mass squared of the lepton pair q(2), the amplitude of the signal channel (p) over barp -> e(+)e(-)pi(0) admits a QCD factorized description in terms of pi N TDAs and nucleon Distribution Amplitudes (DAs) in the forward aid backward kinematic regimes. Assuming the validity of this factorized description, we perform feasibility studies for measuring (p) over barp -> e(+)e(-)pi(0) with the PANDA detector. Detailed simulations on signal reconstruction efficiency as well as on rejection of the most severe background channel, i.e. (p) over barp -> pi(+)pi(-)pi(0) were performed for the center-of-mass energy squared s = 5 GeV2 and s = 10 GeV2, in the kinematic regions 3.0 < q(2) < 4.3 GeV2 and 5 < q(2) < 9 GeV2, respectively, with a neutral pion scattered in the forward or backward cone vertical bar cos theta(pi 0)vertical bar > 0.5 in the proton-antiproton center-of-mass frame. Results of the simulation show that the particle identification capabilities of the PANDA detector will allow to achieve a background rejection factor of 5 . 10(7) (1 . 10(7)) at low (high) q(2) for s = 5 GeV2, and of 1 . 10(8) (6 . 10(6)) at low (high) q(2) for s = 10 GeV2, while keeping the signal reconstruction efficiency at around 40%. At both energies, a clean lepton signal can be reconstructed with the expected statistics corresponding to 2 of integrated luminosity. The cross sections obtained from the simulations are used to show that a test of QCD collinear factorization can be done at the lowest order by measuring scaling laws and angular distributions. The future measurement of the signal channel cross section with PANDA will provide a new test of the perturbative QCD description of a novel class of hard exclusive reactions and will open the possibility of experimentally accessing pi N TDAs.

  • 265. Singh, B. S. Nara
    et al.
    Steer, A. N.
    Jenkins, D. G.
    Wadsworth, R.
    Bentley, M. A.
    Davies, P. J.
    Glover, R.
    Pattabiraman, N. S.
    Lister, C. J.
    Grahn, T.
    Greenlees, P. T.
    Jones, P.
    Julin, R.
    Juutinen, S.
    Leino, M.
    Nyman, M.
    Pakarinen, J.
    Rahkila, P.
    Saren, J.
    Scholey, C.
    Sorri, J.
    Uusitalo, J.
    Butler, P. A.
    Dimmock, M.
    Joss, D. T.
    Thomson, J.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Hadinia, B.
    Sandzelius, M.
    Coulomb shifts and shape changes in the mass 70 region2007In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 75, no 6Article in journal (Refereed)
    Abstract [en]

    The technique of recoil beta tagging has been developed which allows prompt gamma decays in nuclei from excited states to be correlated with electrons from their subsequent short-lived beta decay. This technique is ideal for studying nuclei very far from stability and improves in sensitivity for very short-lived decays and for high decay Q-values. The method has allowed excited states in Y-78 to be observed for the first time, as well as an extension in the knowledge of T=1 states in Rb-74. From this new information it has been possible to compare Coulomb energy differences (CED) between T=1 states in Br-70/Se-70, Rb-74/Kr-74, and Y-78/Sr-78. The A=70 CED exhibit an anomalous behavior which is inconsistent with all other known CED. This behavior may be accounted for qualitatively in terms of small variations in the Coulomb energy arising from shape changes.

  • 266. Singh, B. S. Nara
    et al.
    Steer, A. N.
    Jenkins, D. G.
    Wadsworth, R.
    Davies, P. J.
    Glover, R.
    Pattabiraman, N. S.
    Grahn, T.
    Greenlees, P. T.
    Jones, P.
    Julin, R.
    Leino, M.
    Nyman, M.
    Pakarinen, J.
    Rahkila, P.
    Scholey, C.
    Sorri, J.
    Uusitalo, J.
    Butler, P. A.
    Dimmock, M.
    Joss, D. T.
    Thomson, J.
    Lister, C. J.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Hadinia, Baharak
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Sandzelius, Mikael
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Recoil Beta Tagging: Application to the study of odd-odd near proton drip line nuclei, Rb-74 and Y-782007In: The European Physical Journal Special Topics, ISSN 1951-6355, E-ISSN 1951-6401, Vol. 150, p. 147-148Article in journal (Refereed)
    Abstract [en]

    We present a study of low-spin states in Rb-74 and Y-78 using the new technique of Recoil Beta Tagging. This yielded new information on Rb-74 and has provided the first evidence for non-isomeric T = 1 states in Y-78.

  • 267. Smith, J. F.
    et al.
    Chiara, C. J.
    Carpenter, M. P.
    Davids, C. N.
    Devlin, M.
    Fossan, D. B.
    Freeman, S. J.
    Janssens, R. V. F.
    LaFosse, D. R.
    Sarantites, D. G.
    Seweryniak, D.
    Starosta, K.
    Wadsworth, R.
    Wilson, A. N.
    Wyss, Ramon
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Excited states and signature inversion in Cs-1162006In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 74, no 3, p. 034310-Article in journal (Refereed)
    Abstract [en]

    Excited states have been observed for the first time in the very neutron-deficient, odd-odd nucleus, Cs-116(55)61. The assignment to Cs-116 has been made by the detection of gamma rays in coincidence with evaporated charged particles and with evaporation residues. The observed states form a rotational band which has been assigned to the nu(h(11/2)) circle times pi(h(11/2)) configuration. Tentative spin assignments have been made on the basis of systematic comparisons with neighboring cesium isotopes. A low-spin signature inversion is observed in the band at a rotational frequency of about 0.23 MeV/h. The observed signature inversions in the odd-odd Cs116-126 isotopes have been compared with the results of extended total Routhian surface calculations, in which signature inversion arises as a consequence of quadrupole-pairing correlations and triaxial deformation. As previously shown for some of the odd-odd A similar or equal to 120 isotopes, the calculations reproduce the signature inversions reasonably well.

  • 268. Soderstrom, P. -A
    et al.
    Recchia, F.
    Nyberg, J.
    Gadea, A.
    Lenzi, S. M.
    Poves, A.
    Atac, A.
    Aydin, S.
    Bazzacco, D.
    Bednarczyk, P.
    Bellato, M.
    Birkenbach, B.
    Bortolato, D.
    Boston, A. J.
    Boston, H. C.
    Bruyneel, B.
    Bucurescu, D.
    Calore, E.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Charles, L.
    Chavas, J.
    Colosimo, S.
    Crespi, F. C. L.
    Cullen, D. M.
    de Angelis, G.
    Desesquelles, P.
    Dosme, N.
    Duchene, G.
    Eberth, J.
    Farnea, E.
    Filmer, F.
    Gorgen, A.
    Gottardo, A.
    Grebosz, J.
    Gulmini, M.
    Hess, H.
    Hughes, T. A.
    Jaworski, G.
    Jolie, J.
    Joshi, P.
    Judson, D. S.
    Jungclaus, A.
    Karkour, N.
    Karolak, M.
    Kempley, R. S.
    Khaplanov, Anton
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Korten, W.
    Ljungvall, J.
    Lunardi, S.
    Maj, A.
    Maron, G.
    Meczynski, W.
    Menegazzo, R.
    Mengoni, D.
    Michelagnoli, C.
    Molini, P.
    Napoli, D. R.
    Nolan, P. J.
    Norman, M.
    Obertelli, A.
    Podolyak, Zs.
    Pullia, A.
    Quintana, B.
    Redon, N.
    Regan, P. H.
    Reiter, P.
    Robinson, A. P.
    Sahin, E.
    Simpson, J.
    Salsac, M. D.
    Smith, J. F.
    Stezowski, O.
    Theisen, Ch.
    Tonev, D.
    Unsworth, C.
    Ur, C. A.
    Valiente-Dobon, J. J.
    Wiens, A.
    High-spin structure in K-402012In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 86, no 5, p. 054320-Article in journal (Refereed)
    Abstract [en]

    High-spin states of K-40 have been populated in the fusion-evaporation reaction C-12(Si-30,np)K-40 and studied by means of gamma-ray spectroscopy techniques using one triple-cluster detector of the Advanced Gamma Tracking Array at the Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro. Several states with excitation energy up to 8 MeV and spin up to 10(-) have been discovered. These states are discussed in terms of J = 3 and T = 0 neutron-proton hole pairs. Shell-model calculations in a large model space have shown good agreement with the experimental data for most of the energy levels. The evolution of the structure of this nucleus is here studied as a function of excitation energy and angular momentum.

  • 269. Sohler, D.
    et al.
    Palacz, M.
    Dombradi, Z.
    Hjorth-Jensen, M.
    Fahlander, C.
    Norlin, L. O.
    KTH, School of Engineering Sciences (SCI), Physics.
    Nyberg, J.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics.
    Lagergren, K.
    KTH, School of Engineering Sciences (SCI), Physics.
    Cederkäll, J
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Johnson, Arne
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Kerek, A.
    KTH, School of Engineering Sciences (SCI), Physics.
    Klamra, Wlodzimierz
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Wolinska, M.
    et al, .
    Maximally aligned states in the proton drip line nucleus Sb-1062005In: Nuclear Physics A, ISSN 0375-9474, E-ISSN 1873-1554, Vol. 753, no 04-mar, p. 251-262Article in journal (Refereed)
    Abstract [en]

    High-spin states in Sb-106 have been investigated in the Fe-54(Ni-58, 1α 1p1n) reaction by in-beam γ-spectroscopic methods using the EUROBALL detector array equipped with charged particle and neutron detectors. On the basis of measured γγ-coincidence relations, angular distributions, and linear polarization ratios a significantly extended level scheme has been constructed up to spin and parity I-π = (19(-)) and E-x &SIM; 6.5 MeV. The experimental results are interpreted within the framework of the gdsh shell model using a realistic effective nucleon-nucleon interaction. Candidates for states with fully aligned angular momenta in the π(d(5/2), g(7/2))(1) v (d(5/2), g(7/2))(5) valence space are identified at 4338 and 5203 keV, as well as in the π(d(5/2), g(7/2))(1) V(d(5/2), g(7/2))(4)h(11/2)(1) space at 6087, 6573 and 6783 keV. © 2005 Elsevier B.V. All rights reserved.

  • 270. Stefanova, E. A.
    et al.
    Lieb, K. P.
    Stefanescu, I.
    De Angelis, G.
    Curien, D.
    Eberth, J.
    Farnea, E.
    Gadea, A.
    Gersch, G.
    Jungclaus, A.
    Martinez, T.
    Schwengner, R.
    Steinhardt, T.
    Warr, N.
    Weisshaar, D.
    Wyss, Ramon
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Observation of negative-parity high-spin states of As-682005In: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 24, no 1, p. 1-4Article in journal (Refereed)
    Abstract [en]

    The neutron-deficient nucleus As-68 was populated at high spin in two experiments using the reaction Ca-40(S-32, 3pn) at beam energies of 105 and 95 MeV. A self-supporting and a gold-backed, highly enriched Ca-40 target were used. Gamma rays were detected with the EUROBALL array, combined with the charged-particle detector array EUCLIDES and the Neutron Wall. The As-68 level scheme was considerably extended, especially at negative parity and many previous spin-parity assignments were confirmed or rejected. The total-Routhian-surface (TRS) calculations find shape coexistence and γ softness for the negative- and positive-parity states, respectively.

  • 271. Sun, M. D.
    et al.
    Liu, Z.
    Huang, T. H.
    Zhang, W. Q.
    Wang, J. G.
    Liu, X. Y.
    Ding, B.
    Gan, Z. G.
    Ma, L.
    Yang, H. B.
    Zhang, Z. Y.
    Yu, L.
    Jiang, J.
    Wang, K. L.
    Wang, Y. S.
    Liu, M. L.
    Li, Z. H.
    Li, J.
    Wang, X.
    Lu, H. Y.
    Lin, C. J.
    Sun, L. J.
    Ma, N. R.
    Yuan, C. X.
    Zuo, W.
    Xu, H. S.
    Zhou, X. H.
    Xiao, G. Q.
    Qi, Chong
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Zhang, F. S.
    New short-lived isotope 223Np and the absence of the Z = 92 subshell closure near N = 1262017In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 771, p. 303-308Article in journal (Refereed)
    Abstract [en]

    The N=130 short-lived isotope 223Np was produced as evaporation residue (ER) in the fusion reaction 40Ar + 187Re at the gas-filled recoil separator Spectrometer for Heavy Atom and Nuclear Structure (SHANS). It was identified through temporal and spatial correlations with α decays of 215Ac and/or 211Fr, the third and fourth members of the α-decay chain starting from 223Np. The pileup signals of ER(223Np)–α(223Np)–α(219Pa) were resolved by using the digital pulse processing technique. An α decay with half-life of T1/2=2.15(52100) μs and energy of Eα=9477(44) keV was attributed to 223Np. Spin and parity of 9/2− were tentatively proposed for the ground state of 223Np by combining the reduced α-decay width and large-scale shell-model calculations. This assignment together with the proton separation energy disprove the existence of a Z=92 subshell closure.

  • 272. Szymanska, K.
    et al.
    Achenbach, P.
    Agnello, M.
    Botta, E.
    Bracco, A.
    Bressani, T.
    Camera, F.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Feliciello, A.
    Ferro, F.
    Gerl, J.
    Iazzi, F.
    Kavatsyuk, M.
    Kojouharov, I.
    Pochodzalla, J.
    Raciti, G.
    Saito, T. R.
    Lorente, A. Sanchez
    Tegnér, P. -E
    Wieland, O.
    Resolution, efficiency and stability of HPGe detector operating in a magnetic field at various gamma-ray energies2008In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 592, no 3, p. 486-492Article in journal (Refereed)
    Abstract [en]

    The use of High Purity Germanium detectors (HPGe) has been planned in some future experiments of hadronic physics. The crystals will be located close to large spectrometers where the magnetic fringing field will not be negligible and their performances might change. Moreover high precision is required in these experiments. The contribution of magnetic field presence and long term measurements is unique. In this paper the results of systematic measurements of the resolution, stability and efficiency of a crystal operating inside a magnetic field of 0.8 T, using radioactive sources in the energy range from 0.08 to 1.33 MeV, are reported. The measurements have been repeated during several months in order to test if any permanent damage occurred. The resolution at 1.117 and 1.332 MeV gamma-rays from a Co-60 source has been measured at different magnetic fields in the range of 0-0.8 T and the results are compared with the previous data.

  • 273.
    Söderstrom, P. -A
    et al.
    Uppsala University, Department of Physics and Astronomy.
    Khaplanov, Anton
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    et al,
    Interaction position resolution simulations and in-beam measurements of the AGATA HPGe detectors2011In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 638, no 1, p. 96-109Article in journal (Refereed)
    Abstract [en]

    The interaction position resolution of the segmented HPGe detectors of an AGATA triple cluster detector has been studied through Monte Carlo simulations and in an in-beam experiment. A new method based on measuring the energy resolution of Doppler-corrected gamma-ray spectra at two different target to detector distances is described. This gives the two-dimensional position resolution in the plane perpendicular to the direction of the emitted gamma-ray. The gamma-ray tracking was used to determine the full energy of the gamma-rays and the first interaction point, which is needed for the Doppler correction. Five different heavy-ion induced fusion-evaporation reactions and a reference reaction were selected for the simulations. The results of the simulations show that the method works very well and gives a systematic deviation of <1 mm in the FVVHM of the interaction position resolution for the gamma-ray energy range from 60 keV to 5 MeV. The method was tested with real data from an in-beam measurement using a (30)5i beam at 64 MeV on a thin C-12 target. Pulse-shape analysis of the digitized detector waveforms and gamma-ray tracking was performed to determine the position of the first interaction point, which was used for the Doppler corrections. Results of the dependency of the interaction position resolution on the gamma-ray energy and on the energy, axial location and type of the first interaction point, are presented. The FVVHM of the interaction position resolution varies roughly linearly as a function of gamma-ray energy from 8.5 mm at 250 key to 4 mm at 1.5 MeV, and has an approximately constant value of about 4 mm in the gamma-ray energy range from 1.5 to 4 MeV.

  • 274. Tashenov, S.
    et al.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Barday, R.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Enders, J.
    Khaplanov, Anton
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Fritzsche, Y.
    Schässburger, Kai-Uwe
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Surzhykov, A.
    Yerokhin, V. A.
    Observation of the spin-orbit interaction in bremsstrahlung2013In: Physica scripta. T, ISSN 0281-1847, Vol. T156, p. 014071-Article in journal (Refereed)
    Abstract [en]

    The effects of the spin-orbit interaction are pronounced for an electron scattered in a Coulomb field of the nucleus. They cause the electron scattering plane to turn or precess as the electron moves. This precession is visible through linear polarization of bremsstrahlung. The first experiment to observe it is described in this contribution.

  • 275. Tashenov, S.
    et al.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Barday, R.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Enders, J.
    Khaplanov, Anton
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Fritzsche, Yu
    Schässburger, Kai-Uwe
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Surzhykov, A.
    Yerokhin, V. A.
    Jakubassa-Amundsen, D.
    Bremsstrahlung polarization correlations and their application for polarimetry of electron beams2013In: Physical Review A. Atomic, Molecular, and Optical Physics, ISSN 1050-2947, E-ISSN 1094-1622, Vol. 87, no 2, p. 022707-Article in journal (Refereed)
    Abstract [en]

    Linear polarization of hard x rays emitted in the process of atomic-field electron bremsstrahlung has been measured with a polarized electron beam. The correlation between the initial orientation of the electron spin and the angle of photon polarization has been systematically studied by means of Compton and Rayleigh polarimetry techniques applied to a segmented germanium detector. The results are in good agreement with those of fully relativistic calculations. The observed correlations are also explained classically and in a unique way manifest that due to the spin-orbit interaction the electron scattering trajectory is not confined to a single scattering plane. The developed photon polarimetry technique with a passive scatterer is very efficient and accurate and thus allows for additional applications. Bremsstrahlung polarization correlations lead to an alternative method of polarimetry of electron beams. Such a method is sensitive to all three components of the electron spin. It can be applied in a broad range of the electron beam energies from approximate to 100 keV up to a few tens of MeV. The results of a measurement at 100 keV are shown. The optimum scheme for electron polarimetry is analyzed and the relevant theoretical predictions are presented.

  • 276. Tashenov, S.
    et al.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics.
    Barday, R.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Enders, J.
    Khaplanov, Anton
    KTH, School of Engineering Sciences (SCI), Physics.
    Fritzsche, Yu.
    Surzhykov, A.
    Yerokhin, V. A.
    Jakubassa-Amundsen, D.
    Electron polarimetry with bremsstrahlung2014In: Journal of Physics, Conference Series, ISSN 1742-6588, E-ISSN 1742-6596, Vol. 488, no SECTION 1, article id 012057Article in journal (Refereed)
    Abstract [en]

    Due to the spin-orbit interaction, the electron scattering from the nucleus is sensitive to the spin orientation of that electron. This is used for polarimetry of electron beams in the Mott method. The spin-orbit interaction was also observed in bremsstrahlung. In this article we analyze its potential for polarimetry as an alternative to the Mott method. It can simultaneously measure all three electron polarization components. It should work in the energy range of 50 keV up to several MeV and can be applied at beam intensities higher than 100 nA. It needs a thin heavy element target, two or four x-ray detectors and one x-ray linear polarimeter.

  • 277. Tashenov, S.
    et al.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Khaplanov, Anton
    Schässburger, Kai-Uwe
    Barday, R.
    Enders, J.
    Poltoratska, Y.
    Surzhykov, A.
    Yerokhin, V.
    Jakubassa-Amundsen, D.
    Bremsstrahlung polarization correlations and their application for polarimetry of electron beams2014In: Journal of Physics, Conference Series, ISSN 1742-6588, E-ISSN 1742-6596, Vol. 488, no SECTION 4, article id 042021Article in journal (Refereed)
    Abstract [en]

    The correlation between electron spin and photon linear polarization in atomic-field bremsstrahlung was measured with a polarized electron beam. The angle of photon polarization and the photon emission intensity were found to be correlated with the spin orientation. These effects are interpreted in terms of spin-orbit interaction. They lead to a new technique of electron beam polarimetry.

  • 278. Tashenov, Stanislav
    et al.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Barday, R.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Enders, J.
    Khaplanov, Anton
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Poltoratska, Yu.
    Schassburger, Kai-Uwe
    Surzhykov, A.
    Measurement of the Correlation between Electron Spin and Photon Linear Polarization in Atomic-Field Bremsstrahlung2011In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 107, no 17, p. 173201-Article in journal (Refereed)
    Abstract [en]

    Atomic-field bremsstrahlung has been studied with a longitudinally polarized electron beam. The correlation between the initial orientation of the electron spin and the angle of photon polarization has been measured at the photon high energy tip region. In the time reversal this corresponds to a so-far unobserved phenomenon of production of longitudinally polarized electrons by photoionization of unpolarized atoms with linearly polarized photons. The results confirm the fully relativistic calculations for radiative recombination and suggest a new method for electron beam polarimetry.

  • 279.
    Tashenov, Stanislav
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Gerl, J.
    GSI Helmholtzzentrum Fr Schwerionenforschung GmbH (GSI).
    TANGO: New tracking AlGOrithm for gamma-rays2010In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 622, no 3, p. 592-601Article in journal (Refereed)
    Abstract [en]

    For spectroscopy, polarimetry and imaging purposes a new gamma-ray tracking algorithm has been developed featuring identification of Compton escape events. The rejection of these events results in a significant increase of the Peak/Total ratio. The initial photon energy is restored for these events. Although the energy resolution in the spectrum reconstructed from the escape events is lower than the one from the full-energy events, the Monte-Carlo simulations show that the combined spectrum has an increased detector full-energy efficiency of up to 130% compared to its intrinsic full-energy efficiency. The assumed geometrical origin of the photons is verified event-by-event. This enables separation of photons emitted from a target and from background sources. A linear polarization analysis of the gamma-lines can be performed. The efficiency of the algorithm and the Peak/Total ratio depending on the detector properties is discussed along with the proposed optimization schemes. The influence of the intrinsic properties of the scattering process like Compton profile and electron recoiling is discussed as well. The described algorithm deals with single photon events with energies of approximate to 100 keV up to a few MeV.

  • 280.
    Tashenov, Stanislav
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Khaplanov, Anton
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Gamma-ray tracking and background suppression in the planned germanium array of DESPEC: A comparative analysis2009In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 604, no 1-2, p. 64-66Article in journal (Refereed)
    Abstract [en]

    A new high efficiency gamma-ray spectrometer is being designed for the DESPEC project at FAIR. It should accomplish all types of decay studies with implanted radioactive ion beams. The gamma-ray tracking and imaging capabilities of the array will be its essential property allowing low background detection of the rare decay events. For this purpose two types of germanium detectors are considered, i.e. segmented planar and coaxial detectors. Several final array configurations based on these detectors, differently segmented, are evaluated and compared in this paper.

  • 281.
    Tashenov, Stanislav
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Khaplanov, Anton
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Schässburger, Kai-Uwe
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Hard X-ray polarimetry by means of Rayleigh scattering2009In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 600, no 3, p. 599-603Article in journal (Refereed)
    Abstract [en]

    A new linear polarimetry technique based on Rayleigh scattering is introduced. Its properties are compared to the Compton technique. Experimental verification was realized using a 5 x 5 segmented planar HPGe pixel detector. In the proof-of-principle experiment a measurement of Rayleigh scattering off lead atoms was performed for linearly polarized; approximate to 53.3 keV photons at two scattering angles.

  • 282. Taylor, M. J.
    et al.
    Cullen, D. M.
    Procter, M. G.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Doncel, Maria
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Braunroth, T.
    Dewald, A.
    Pakarinen, J.
    Grahn, T.
    Greenlees, P. T.
    Auranen, K.
    Jakobsson, U.
    Julin, R.
    Juutinen, S.
    Herzan, A.
    Konki, J.
    Leino, M.
    Liotta, R.
    Partanen, J.
    Peura, P.
    Rahkila, P.
    Ruotsalainen, P.
    Sandzelius, M.
    Saren, J.
    Sorri, J.
    Stolze, S.
    Uusitalo, J.
    Liang, W. Y.
    Xu, F. R.
    Competing single-particle and collective states in the low-energy structure of I-1132013In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 88, no 5, p. 054307-Article in journal (Refereed)
    Abstract [en]

    To understand the low-energy structure of the neutron deficient iodine isotopes, lifetimes for the low-lying 9/2(+) and 11/2(+) positive-parity states in I-113 have been measured as tau = 28(4) ps and tau = 3.7(7) ps, respectively. The lifetime for the 11/2(-) state, which feeds the 9/2(+) and 11/2(+) states, was remeasured with improved accuracy as tau = 216(7) ps. The reduced transition probability, B(E2) = 32(5) W.u., for the 9/2(+) -> 5/2(+) transition agrees with that calculated within the shell model using a Hamiltonian based on the charge-dependent Bonn nucleon-nucleon interaction. In contrast, the much larger transition probability, B(E2) = 209(39) W.u., measured for the 11/2(+) -> 7/2(+) transition has been interpreted, with the aid of configuration-constrained total Routhian surface calculations, as resulting from a slightly gamma-soft rotor with an associated quadrupole deformation of beta(2) approximate to 0.18. Remarkably similar reduced E1 transition probabilities of 5.5(5) x 10(-4) and 4.9(5) x 10(-4) W.u. were deduced for the 11/2(-) -> 9/2(+) and 11/2(-) -> 11/2(+) transitions, respectively, which feed apparently dissimilar but competing structures.

  • 283.
    Tesinsky, Milan
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Physics.
    Berglöf, Carl
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Physics.
    Bäck, Torbjörn
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Martsynkevich, Boris
    Serafimovich, Ivan
    Bournos, Victor
    Khilmanovich, Anatoly
    Fokov, Yurii
    Korneev, Sergey
    Kiyavitskaya, Hanna
    Gudowski, Waclaw
    KTH, School of Engineering Sciences (SCI), Physics, Reactor Physics.
    Comparison of calculated and measured reaction rates obtained through foil activation in the subcritical dual spectrum facility YALINA-Booster2011In: Annals of Nuclear Energy, ISSN 0306-4549, E-ISSN 1873-2100, Vol. 38, no 6, p. 1412-1417Article in journal (Refereed)
    Abstract [en]

    Reaction rates were measured by the foil activation technique to obtain neutron spectrum information in a subcritical core driven by an external neutron source. The experimental results are compared with Monte Carlo calculations in order to examine the capability of the Monte Carlo code MCNP together with ENDFB-6.8. JEFF-3.1.1 and CENDL-3.1 neutron cross section libraries to predict the neutron spectrum dependent reaction rates correctly in a subcritical core. The focus lies on fast neutrons. A discrepancy is found in the calculated-to-experimental values of the reaction rates and an inaccurate cross section is identified in CENDL-3.1. 

  • 284. Thomson, J.
    et al.
    Joss, D. T.
    Paul, E. S.
    Scholey, C.
    Simpson, J.
    Erturk, S.
    Bianco, L.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Darby, I. G.
    Eeckhaudt, S.
    Gomez-Hornillos, M. B.
    Grahn, T.
    Greenlees, P. T.
    Hadinia, Baharak
    KTH, School of Engineering Sciences (SCI), Physics.
    Jones, P.
    Julin, R.
    Juutinen, S.
    Ketelhut, S.
    Leino, M.
    Nyman, M.
    O'Donnell, D.
    Page, R. D.
    Pakarinen, J.
    Rahkila, P.
    Rowley, N.
    Sandzelius, Mikael
    KTH, School of Engineering Sciences (SCI), Physics.
    Sapple, P. J.
    Saren, J.
    Sorri, J.
    Uusitalo, J.
    Competing quasiparticle configurations in W-1632010In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 81, no 1Article in journal (Refereed)
    Abstract [en]

    Excited states in the neutron-deficient nuclide W-163 were investigated using the Cd-106(Ni-60, 2pn)W-163 reaction at a beam energy of 270 MeV. The level scheme for W-163 was extended significantly with the observation of five new band structures. The yrast band based on a 13/2(+) isomeric state is extended up to (57/2(+)). Two band structures were established on the 7/2(-) ground state. Quasiparticle configuration assignments for the new band structures were made on the basis of cranked Woods-Saxon shell-model calculations. The results reported in this article suggest that the negative-parity nu(f(7/2), h(9/2)) orbitals are responsible for the first rotational alignment in the yrast band.

  • 285.
    Thörngren Engblom, Pia
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    A complete low-energy polarized proton-deuteron breakup experiment2014In: Physics of particles and nuclei, ISSN 1063-7796, E-ISSN 1090-6495, Vol. 45, no 1, p. 193-195Article in journal (Refereed)
    Abstract [en]

    An experiment at low energy will be done at the COSY cooler synchrotron and storage ring in order to study the three-particle final states of proton-deuteron scattering reactions measuring a complete set of single and double spin observables over large areas of phase space. The physics objective is to test the predictive power of chiral effective field theory at an energy where convergence is guaranteed and few previous measurements exist. A direct comparison between theoretical predictions and experimental data will be enabled by the use of the so called sampling method.

  • 286.
    Thörngren Engblom, Pia
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics. Uppsala Universitet.
    Fysik och svensk historieskrivning2003Other (Other (popular science, discussion, etc.))
    Abstract [sv]

    Här ges en beskrivning av det historiska skeendet kring upptäckten av kärnklyvning och Lise Meitners roll i denna. Artikeln är en replik till Indrek Martinsson och Ingolf Lindau och diskuterar svensk historieskrivning kring fissionens upptäckt och politiska hänsyn.

  • 287.
    Thörngren Engblom, Pia
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Bertelli, S.
    Contalbrigo, M.
    Lenisa, P.
    Chiladze, D.
    Kacharava, A.
    Lorentz, B.
    Nass, A.
    Oellers, D.
    Rathmann, F.
    Schleichert, R.
    Ströher, H.
    Weidemann, C.
    Lomidze, N.
    Tabidze, M.
    Macharashvili, G.
    Merzlyakov, S.
    Barsov, S.
    Mikirtytchiants, S.
    Extensive high-precision studies of proton deuteron breakup reactions at COSY2011In: Proceedings of Science, Sissa Medialab Srl , 2011Conference paper (Refereed)
    Abstract [en]

    We plan to measure the spin dependence of proton deuteron breakup at 30 and 49 MeV proton beam energy where previous measurements are few and limited. The physics objective is to test the predictive power of the chiral effective field theory in the three nucleon continuum by measuring analyzing powers and double spin observables with high precision over large areas of phase space at relevant energies for the theoretical interpretation. The experiment will be done at a newly installed and commissioned low-b section and interaction point in the COSY ring utilizing the PAX Multipurpose Detection System that is presently in the design stage. 

  • 288. Van de Vel, K.
    et al.
    Andreyev, A. N.
    Ackermann, D.
    Boardman, H. J.
    Cagarda, P.
    Gerl, J.
    Hessberger, F. P.
    Hofmann, S.
    Huyse, M.
    Karlgren, Daniel
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Kojouharov, I.
    Leino, M.
    Lommel, B.
    Munzenberg, G.
    Moore, C.
    Page, R. D.
    Saro, S.
    Van Duppen, P.
    Wyss, Ramon
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Prolate structures in Po-189 and Pb-1852005In: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 24, no 1, p. 57-62Article in journal (Refereed)
    Abstract [en]

    The 3/2(-) isomer in Pb-185 and states above it have been populated in the α-decay of Po-189. The observed α-decay strengths to and the electromagnetic decay properties of the excited states in Pb-185 have been combined with Potential Energy Surface and Particle-Plus-Rotor calculations to propose configuration assignments. It is suggested that the α-decaying isomer of Po-189 is of prolate origin and that the prolate configuration becomes very low in energy in Pb-185.

  • 289. Vandone, V.
    et al.
    Leoni, S.
    Benzoni, G.
    Blasi, N.
    Bracco, A.
    Brambilla, S.
    Boiano, C.
    Bottoni, S.
    Camera, F.
    Corsi, A.
    Crespi, F. C. L.
    Giaz, A.
    Million, B.
    Nicolini, R.
    Pellegri, L.
    Pullia, A.
    Wieland, O.
    Bortolato, D.
    de Angelis, G.
    Calore, E.
    Gottardo, A.
    Maron, G.
    Napoli, D. R.
    Rosso, D.
    Sahin, E.
    Valiente-Dobon, J. J.
    Bazzacco, D.
    Bellato, M.
    Farnea, E.
    Lunardi, S.
    Menegazzo, R.
    Mengoni, D.
    Molini, P.
    Michelagnoli, C.
    Montanari, D.
    Recchia, F.
    Ur, C. A.
    Gadea, A.
    Hueyuek, T.
    Cieplicka, N.
    Maj, A.
    Kmiecik, M.
    Atac, A.
    Akkoyun, S.
    Kaskas, A.
    Soederstroem, P. -A
    Birkenbach, B.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Coleman-Smith, P. J.
    Cullen, D. M.
    Desesquelles, P.
    Eberth, J.
    Goergen, A.
    Grebosz, J.
    Hess, H.
    Judson, D.
    Jungclaus, A.
    Karkour, N.
    Nolan, P.
    Obertelli, A.
    Reiter, P.
    Salsac, M. D.
    Stezowski, O.
    Theisen, Ch.
    Matsuo, M.
    Vigezzi, E.
    Global properties of K hindrance probed by the gamma decay of the warm rotating W-174 nucleus2013In: Physical Review C. Nuclear Physics, ISSN 0556-2813, E-ISSN 1089-490X, Vol. 88, no 3, p. 034312-Article in journal (Refereed)
    Abstract [en]

    The K hindrance to the gamma decay is studied in the warm rotating W-174 nucleus, focusing on the weakening of the selection rules of the K quantum number with increasing excitation energy. W-174 was populated by the fusion reaction of Ti-50 (at 217 MeV) on a Te-128 target, and its gamma decay was detected by the AGATA Demonstrator array coupled to a BaF2 multiplicity filter at Laboratori Nazionali di Legnaro of INFN. A fluctuation analysis of gamma coincidence matrices gives a similar number of low-K and high-K discrete excited bands. The results are compared to simulations of the gamma-decay flow based on a microscopic cranked shell model at finite temperature in which the K mixing is governed by the interplay of Coriolis force with the residual interaction. Agreement between simulations and experiment is obtained only by hindering the E1 decay between low-K and high-K bands by an amount compatible with that determined by spectroscopic studies of K isomers in the same mass region, with a similar trend with excitation energy. The work indicates that K mixing due to temperature effects may play a leading role for the entire body of discrete excited bands, which probes the onset region of K weakening.

  • 290. Vinas, X.
    et al.
    Bhagwat, A.
    Centelles, M.
    Schuck, P.
    Wyss, Ramon
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Applications to nuclear properties of the microscopic-macroscopic model based on the semiclassical Wigner-Kirkwood method2015In: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. 90, no 11, article id 114001Article in journal (Refereed)
    Abstract [en]

    Some time ago we proposed a new microscopic-macroscopic model where the semiclassical Wigner-Kirkwood expansion of the energy up to fourth-order in. is used to compute the shell corrections in a deformed Woods-Saxon potential instead of the usual Strutinsky averaging scheme. For a set of 558 even-even nuclei computed with this new model, we found a rms deviation of 610 keV from the experimental masses, similar to the value obtained using the well-known finite range droplet model and the Lublin-Strasbourg drop model for the same set of nuclei. In this paper we analyze the alpha radioactivity in nuclei with mass number A similar to 100, finding good agreement with the available experimental results. We have also estimated spontaneous fission half-lives for superheavy nuclei in the region between Z = 102 and Z = 110. We find that our model predicts reasonably well the experimental half-lives in the considered nuclei, in spite of the fact that the fission barriers turn out to be somewhat too high.

  • 291. Wadsworth, R.
    et al.
    Singh, B. S. Nara
    Steer, A. N.
    Jenkins, D. C.
    Bentley, M. A.
    Brock, T.
    Davies, P.
    Glover, R.
    Pattabiraman, N. S.
    Scholey, C.
    Grahn, T.
    Greenlees, P. T.
    Jones, P.
    Jakobsson, U.
    Julin, R.
    Juutinen, S.
    Ketelhut, S.
    Leino, M.
    Nyman, M.
    Perua, P.
    Pakarinen, J.
    Rahkila, P.
    Ruotslainen, P.
    Sorri, J.
    Uusitalo, J.
    Lister, C. J.
    Butler, P. A.
    Dimmock, M.
    Joss, D. T.
    Thomson, J.
    Rinta-Antila, S.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Hadinia, Baharak
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Sandzelius, Mikael
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Atac, Ayse
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Betterman, L.
    Blazhev, A.
    Braun, N.
    Finke, F.
    Geibel, K.
    Ilie, G.
    Iwasaki, H.
    Jolie, J.
    Reiter, P.
    Scholl, C.
    Warr, N.
    Boutachkov, P.
    Caceres, L.
    Domingo, C.
    Engert, T.
    Farinon, F.
    Gerl, J.
    Goel, N.
    Gorska, M.
    Grawe, H.
    Kurz, N.
    Kojuharov, I.
    Pietri, S.
    Nociforo, C.
    Prochazka, A.
    Wollersheim, H-J
    Eppinger, K.
    Faestermann, T.
    Hinke, C.
    Hoischen, R.
    Kruecken, R.
    Gottardo, A.
    Liu, Z.
    Woods, P.
    Grebosz, J.
    Merchant, E.
    Nyberg, J.
    Soderstrom, P-A
    Podolyak, Z.
    Regan, P.
    Steer, S.
    Pfutzner, M.
    Rudolph, D.
    THE NORTHWEST FRONTIER: SPECTROSCOPY OF N similar to Z NUCLEI BELOW MASS 1002009In: Acta Physica Polonica B, ISSN 0587-4254, E-ISSN 1509-5770, Vol. 40, no 3, p. 611-620Article in journal (Refereed)
    Abstract [en]

    The spectroscopy and structure of excited states of N similar to Z nuclei in the mass 70-100 region has been investigated using two techniques. In the A similar to 70-80 region fusion evaporation reactions coupled with the recoil-beta-tagging method have been employed at Jyvaskyla to study low-lying states in odd-odd N = Z nuclei. Results from these and other data for known odd-odd nuclei above mass 60 will be discussed. In the heavier mass 90 region a fragmentation experiment has been performed using the RIS-ING/FRS setup at GSI. This experiment was primarily aimed at searching for spin gap isomers in nuclei around A similar to 96. The objectives of the latter experiment will be discussed.

  • 292. Wang, F.
    et al.
    Sun, B. H.
    Liu, Z.
    Page, R. D.
    Qi, Chong
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Scholey, C.
    Ashley, S. F.
    Bianco, L.
    Cullen, I. J.
    Darby, I. G.
    Eeckhaudt, S.
    Garnsworthy, A. B.
    Gelletly, W.
    Gomez-Hornillos, M. B.
    Grahn, T.
    Greenlees, P. T.
    Jenkins, D. G.
    Jones, G. A.
    Jones, P.
    Joss, D. T.
    Julin, R.
    Juutinen, S.
    Ketelhut, S.
    Khan, S.
    Kishada, A.
    Leino, M.
    Niikura, M.
    Nyman, M.
    Pakarinen, J.
    Pietri, S.
    Podolyak, Z.
    Rahkila, P.
    Rigby, S.
    Saren, J.
    Shizuma, T.
    Sorri, J.
    Steer, S.
    Thomson, J.
    Thompson, N. J.
    Uusitalo, J.
    Walker, P. M.
    Williams, S.
    Zhang, H. F.
    Zhang, W. Q.
    Zhu, L. H.
    Spectroscopic factor and proton formation probability for the d3/2 proton emitter 151mLu2017In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 770, p. 83-87Article in journal (Refereed)
    Abstract [en]

    The quenching of the experimental spectroscopic factor for proton emission from the short-lived d3/2 isomeric state in 151mLu was a long-standing problem. In the present work, proton emission from this isomer has been reinvestigated in an experiment at the Accelerator Laboratory of the University of Jyväskylä. The proton-decay energy and half-life of this isomer were measured to be 1295(5) keV and 15.4(8) μs, respectively, in agreement with another recent study. These new experimental data can resolve the discrepancy in the spectroscopic factor calculated using the spherical WKB approximation. Using the R-matrix approach it is found that the proton formation probability indicates no significant hindrance for the proton decay of 151mLu.

  • 293. Wang, F.
    et al.
    Sun, B. H.
    Liu, Z.
    Qi, Chong
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Zhu, L. H.
    Scholey, C.
    Ashley, S. F.
    Bianco, L.
    Cullen, I. J.
    Darby, I. G.
    Eeckhaudt, S.
    Garnsworthy, A. B.
    Gelletly, W.
    Gomez-Hornillos, M. B.
    Grahn, T.
    Greenlees, P. T.
    Jenkins, D. G.
    Jones, G. A.
    Jones, P.
    Joss, D. T.
    Julin, R.
    Juutinen, S.
    Ketelhut, S.
    Khan, S.
    Kishada, A.
    Leino, M.
    Niikura, M.
    Nyman, M.
    Page, R. D.
    Pakarinen, J.
    Pietri, S.
    Podolyak, Zs.
    Rahkila, P.
    Rigby, S.
    Saren, J.
    Shizuma, T.
    Sorri, J.
    Steer, S.
    Thomson, J.
    Thompson, N. J.
    Uusitalo, J.
    Walker, P. M.
    Williams, S.
    Reinvestigation of the excited states in the proton emitter Lu-151: Particle-hole excitations across the N = Z=64 subshell2017In: Physical Review C: Covering Nuclear Physics, ISSN 2469-9985, E-ISSN 2469-9993, Vol. 96, no 6, article id 064307Article in journal (Refereed)
    Abstract [en]

    The excited states of the proton emitter Lu-151 were reinvestigated in a recoil-decay tagging experiment at the Accelerator Laboratory of the University of Jyvaskyla (JYFL). The level scheme built on the ground state of 151Lu was updated with five new y-ray transitions. Large-scale shell model calculations were carried out in the model space consisting of the neutron and proton orbitals 0g(7/2), Id(5/2), Id(3/2), 2s(1/2), and Oh(1/2) with the optimized monopole interaction in order to interpret the experimental level scheme of Lu-151. It is found that the excitation energies of states above the 27/2(-) and 23/2(+) isomeric levels in Lu-151 can be sensitive to excitations from g(7/2) and d(5/2) to single-particle orbitals above N = Z = 64.

  • 294.
    Wang, S.
    et al.
    Peking University.
    Xu, C.
    Peking University.
    Liotta, Roberto
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Qi, Chong
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Xu, F.
    Peking University.
    Jiang, D.
    Peking University.
    Alpha-particle decays from excited states in Mg-242011In: Science China: Physics, Mechanics and Astronomy, ISSN 1674-7348, Vol. 54, no 1, p. S130-S135Article in journal (Refereed)
    Abstract [en]

    Using a cluster model based on the Woods-Saxon potential, alpha-particle decays from excited states in Mg-24 have been systematically investigated. Calculations can in general reproduce experimental data, noticing the fact that the preformation factor P of alpha particle in alpha-decaying nuclei is of order from 10(0) to 10(-2). This can be the evidence for the alpha+Ne-20 structure in Mg-24. Meanwhile, the results also show the existence of other configurations, such as O-16+2 alpha. Since the calculated decay widths are very sensitive to the angular momentum carried by the outgoing cluster (alpha particle), our results could serve as a guide to experimental spin assignments.

  • 295. Wang, S. Y.
    et al.
    Komatsubara, T.
    Ma, Y. J.
    Furuno, K.
    Zhang, Y. H.
    Liu, Y. Z.
    Hayakawa, T.
    Mukai, J.
    Iwata, Y.
    Morikawa, T.
    Hagemann, G. B.
    Sletten, G.
    Nyberg, J.
    Jerrestam, D.
    Jensen, H. J.
    Espino, J.
    Gascon, J.
    Gjorup, N.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Tjom, P.
    Band structures in I-1232006In: Journal of Physics G: Nuclear and Particle Physics, ISSN 0954-3899, E-ISSN 1361-6471, Vol. 32, no 3, p. 283-294Article in journal (Refereed)
    Abstract [en]

    Excited states of I-123 were populated via the Cd-116(N-14, alpha 3n) reaction at 65 MeV. The resultant gamma-rays were detected using standard gamma-ray spectroscopic techniques with the NORDBALL detector array. Two previously known positive-parity Delta I = 2 sequences have been extended up to 31/2(+) and 41/2(+). In addition, a number of Delta I = 1 transitions linking the two Delta I = 2 sequences have been observed. It is suggested that both Delta I = 2 sequences are based on a common configuration. This Delta I = 1 band is proposed to be built predominantly on the 97/2[404]7/2(+) oblate configuration, based on the energylevel spectra, B(MI)/B(E2) ratios and the theoretical predictions from the particle-rotor model. The previously identified Delta I = 1 rotational band built on the prolate g(9/2)[404]9/2(+) orbital has also been extended to higher spins. Another previously identified but weakly populated Delta I = 1 band is confirmed and is proposed to be built on the d(5/2)[413]5/2' configuration with the ground state of I-123 as the bandhead.

  • 296. Wang, X. B.
    et al.
    Qi, Chong
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Xu, F. R.
    Isovector channel of quark-meson-coupling model and its effect on symmetry energy2011In: Nuclear Physics A, ISSN 0375-9474, E-ISSN 1873-1554, Vol. 865, no 1, p. 57-68Article in journal (Refereed)
    Abstract [en]

    The non-relativistic approximation Of the quark-meson-coupling model has been discussed and compared with the Skyrme-Hartree-Fock model which includes spin exchanges. Calculations show that the spin-exchange interaction has important effect on the descriptions of finite nuclei and nuclear matter through the Fock exchange. Also in the quark-meson-coupling model, it is the Fock exchange that leads to a nonlinear density-dependent isovector channel and changes the density-dependent behavior of the symmetry energy.

  • 297.
    Wang, X.
    et al.
    Peking University.
    Qi, Chong
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Xu, F.
    Peking University.
    Eigen-Property of Single-j System and Seniority Conservation Condition2012In: Plasma Science and Technology, ISSN 1009-0630, Vol. 14, no 5, p. 383-385Article in journal (Refereed)
    Abstract [en]

    In this paper we study the system with three nucleons within a single-j shell, which can be described as the angular momentum coupling of a nucleon pair and the odd nucleon. The overlaps between these non-orthonormal states form a special matrix coincidental with the one obtained by Rowe and Rosensteel. They proposed a proposition related to the eigenvalue problems of that matrix and dimensions of the associated subspaces. We prove their proposition with the help of the symmetric properties of the six-j symbols. We also derive algebraic expressions for eigen energies as well as conditions for conservation of seniority through the decomposition of the angular momentum.

  • 298. Weidemann, Christian
    et al.
    Thörngren Engblom, Pia
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics. University of Ferrara.
    Wüstner, Peter
    Toward polarized antiprotons: Machine development for spin-filtering experiments2015In: Physical Review Special Topics. Accelerators and Beams, ISSN 1098-4402, E-ISSN 1098-4402, Vol. 18, no 2, article id 020101Article in journal (Refereed)
    Abstract [en]

    The paper describes the commissioning of the experimental equipment and the machine studies required for the first spin-filtering experiment with protons at a beam kinetic energy of 49.3 MeV in COSY. The implementation of a low-β insertion made it possible to achieve beam lifetimes of τb=8000s in the presence of a dense polarized hydrogen storage-cell target of areal density dt=(5.5±0.2)×1013atoms/cm2. The developed techniques can be directly applied to antiproton machines and allow the determination of the spin-dependent p¯p cross sections via spin filtering.

  • 299.
    Westlén, Daniel
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Transmutation of nuclear waste in gas-cooled sub-critical reactors2005Licentiate thesis, comprehensive summary (Other scientific)
  • 300.
    Wimmer, K.
    et al.
    Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan.;RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan..
    Recchia, F.
    Univ Padua, Dipartimento Fis & Astron, I-35131 Padua, Italy.;INFN, Sez Padova, I-35131 Padua, Italy..
    Lenzi, S. M.
    Univ Padua, Dipartimento Fis & Astron, I-35131 Padua, Italy.;INFN, Sez Padova, I-35131 Padua, Italy..
    Riccetto, S.
    Univ Perugia, Dipartimento Fis & Geol, Perugia, Italy.;INFN, Sez Perugia, Perugia, Italy..
    Davinson, T.
    Univ Edinburgh, Sch Phys & Astron, James Clerk Maxwell Bldg, Edinburgh EH9 3FD, Midlothian, Scotland..
    Estrade, A.
    Cent Michigan Univ, Mt Pleasant, MI 48859 USA..
    Griffin, C. J.
    Univ Edinburgh, Sch Phys & Astron, James Clerk Maxwell Bldg, Edinburgh EH9 3FD, Midlothian, Scotland..
    Nishimura, S.
    RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan..
    Nowacki, F.
    CNRS, IN2P3, IPHC, F-67037 Strasbourg, France.;Univ Strasbourg, F-67037 Strasbourg, France..
    Phong, V.
    RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan.;VNU Univ Sci, Fac Phys, 334 Nguyen Trai, Hanoi, Vietnam..
    Poves, A.
    Univ Autonoma Madrid, Dept Theoret Phys, E-28049 Madrid, Spain.;Univ Autonoma Madrid, CSIC, IFT, E-28049 Madrid, Spain..
    Soderstrom, P-A
    Aktas, Özge
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics. KTH Royal Inst Technol, Stockholm, Sweden..
    Al-Aqeel, M.
    Univ Liverpool, Dept Phys, Oliver Lodge Bldg,Oxford St, Liverpool L697ZE, Merseyside, England.;Al Imam Mohammad Ibn Saud Islamic Univ IMISU, Coll Sci, Dept Phys, Riyadh 11623, Saudi Arabia..
    Ando, T.
    Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan..
    Baba, H.
    RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan..
    Bae, S.
    Seoul Natl Univ, Dept Phys & Astron, Seoul 08826, South Korea.;Seoul Natl Univ, Inst Nucl & Particle Astrophys, Seoul 08826, South Korea..
    Choi, S.
    Seoul Natl Univ, Dept Phys & Astron, Seoul 08826, South Korea.;Seoul Natl Univ, Inst Nucl & Particle Astrophys, Seoul 08826, South Korea..
    Doornenbal, P.
    RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan..
    Ha, J.
    RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan.;Seoul Natl Univ, Dept Phys & Astron, Seoul 08826, South Korea..
    Harkness-Brennan, L.
    Univ Liverpool, Dept Phys, Oliver Lodge Bldg,Oxford St, Liverpool L697ZE, Merseyside, England..
    Isobe, T.
    RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan..
    John, P. R.
    Univ Padua, Dipartimento Fis & Astron, I-35131 Padua, Italy.;INFN, Sez Padova, I-35131 Padua, Italy.;Tech Univ Darmstadt, Inst Kernphys, Darmstadt, Germany..
    Kahl, D.
    Univ Edinburgh, Sch Phys & Astron, James Clerk Maxwell Bldg, Edinburgh EH9 3FD, Midlothian, Scotland..
    Kiss, G.
    RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan.;Inst Nucl Res MTA ATOMKI, POB 51, H-4001 Debrecen, Hungary..
    Kojouharov, I.
    GSI Helmholtzzentum Schwerionenforsch GmbH, Darmstadt, Germany..
    Kurz, N.
    GSI Helmholtzzentum Schwerionenforsch GmbH, Darmstadt, Germany..
    Labiche, M.
    STFC Daresbury Lab, Warrington, Cheshire, England..
    Matsui, K.
    Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan..
    Momiyama, S.
    Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan..
    Napoli, D. R.
    INFN, Lab Nazl Legnaro, Legnaro, Padova, Italy..
    Niikura, M.
    Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan..
    Nita, C.
    Horia Hulubei Natl Inst Phys & Nucl Engn IFIN HH, Bucharest, Romania..
    Saito, Y.
    RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan..
    Sakurai, H.
    Univ Tokyo, Dept Phys, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan.;RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan..
    Schaffner, H.
    GSI Helmholtzzentum Schwerionenforsch GmbH, Darmstadt, Germany..
    Schrock, P.
    Univ Tokyo, Ctr Nucl Study, Bunkyo Ku, Tokyo 1130033, Japan..
    Stahl, C.
    Tech Univ Darmstadt, Inst Kernphys, Darmstadt, Germany..
    Sumikama, T.
    RIKEN, Nishina Ctr, 2-1 Hirosawa, Saitama 3510198, Japan..
    Werner, V.
    Tech Univ Darmstadt, Inst Kernphys, Darmstadt, Germany..
    Witt, W.
    GSI Helmholtzzentum Schwerionenforsch GmbH, Darmstadt, Germany.;Tech Univ Darmstadt, Inst Kernphys, Darmstadt, Germany..
    Woods, P. J.
    Univ Edinburgh, Sch Phys & Astron, James Clerk Maxwell Bldg, Edinburgh EH9 3FD, Midlothian, Scotland..
    First spectroscopy of Ti-61 and the transition to the Island of Inversion at N=402019In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 792, p. 16-20Article in journal (Refereed)
    Abstract [en]

    Isomeric states in Ti-59,Ti-61 have been populated in the projectile fragmentation of a 345 AMeV( 238)U beam at the Radioactive Isotope Beam Factory. The decay lifetimes and delayed gamma-ray transitions were measured with the EURICA array. Besides the known isomeric state in Ti-59, two isomeric states in Ti-61 are observed for the first time. Based on the measured lifetimes, transition multipolarities as well as tentative spins and parities are assigned. Large-scale shell model calculations based on the modified LNPS interaction show that both Ti-59 and Ti-61 belong to the Island of Inversion at N = 40 with ground state configurations dominated by particle-hole excitations to the g(9/2 )and d(5/2) orbits.

34567 251 - 300 of 322
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