Monitoring the weak collisional excitation of a stored ion beam reveals the radiative decay rate of extremely long-lived metastable levels
2007 (English)In: Physical Review A. Atomic, Molecular, and Optical Physics, ISSN 1050-2947, E-ISSN 1094-1622, Vol. 76, no 3, 030502- p.Article in journal (Refereed) Published
A fast ion beam stored in an ion storage ring will suffer from collisional interaction with the residual gas even in extreme ultrahigh vacuum. Normally these effects are negligible or easy to correct for. For measurements of extremely long radiative lifetimes of metastable levels we have found that correction for collisional effects is very important and usually limits the accuracy. We now suggest that by monitoring the process of collisional excitation of the metastable level of interest the lifetime value could be determined directly with improved accuracy. The method is applied to available data from our recent measurement of the 5d D-2(5/2) level in Ba+, yielding a value of 32.0 +/- 2.9 s, thus squeezing the error bar by 35%.
Place, publisher, year, edition, pages
2007. Vol. 76, no 3, 030502- p.
IdentifiersURN: urn:nbn:se:kth:diva-37127DOI: 10.1103/PhysRevA.76.030502ISI: 000249786000010ScopusID: 2-s2.0-34648814080OAI: oai:DiVA.org:kth-37127DiVA: diva2:432182