Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Measurements of the Standard Model Higgs boson cross sections in the WW* decay mode with the ATLAS experiment
KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.ORCID iD: 0000-0002-0299-8236
2018 (English)Doctoral thesis, monograph (Other academic)
Abstract [en]

This thesis summarises measurements of the Standard Model Higgs boson production cross sections based on proton–proton collision data at √s = 13 TeV produced by the Large Hadron Collider at CERN. By analysing data collected during 2015 and 2016 by the ATLAS experiment, corresponding to an integrated luminosity of 36 fb−1, the Higgs boson gluon–gluon fusion and vector boson fusion production cross sections are measured in the WW* decay mode. To obtain a high signal to background ratio, the data is filtered for final states with one electron (positron) and one anti-muon (muon) and missing transverse momentum. A major part of the thesis concerns the estimation of backgrounds with misidentified leptons. These backgrounds originate from the production of a W boson and an associated object mistakenly identified as an (anti-)electron or (anti-)muon, and are estimated with data driven techniques. A maximum likelihood fit is performed and the cross sections times branching ratios are simultaneously measured to be σ ·B = 12.6+2.3/-2.1 pb and σ ·B = 0.50+0.30/-0.29 pb for the gluon–gluon fusion and vector boson fusion modes, respectively. Both systematic and statistical uncertainties are taken into account in the confidence intervals. The corresponding Standard Model predictions are 10.4 ± 0.6 pb and 0.81 ± 0.02 pb. The observed (expected) significance of the gluon–gluon fusion mode is 6.3 (5.2) standard deviations above the Standard Model background. For the vector boson fusion mode, the observed and expected significances are 1.9 and 2.7 standard deviations, respectively.

A smaller part of the thesis investigates the prospects for measuring the luminosity in the high-luminosity phase of the Large Hadron Collider, to begin in 2026. ATLAS will build and insert a timing detector with silicon pixel technology into the forward region, to cope with the harsh pileup environment present at high luminosity. The capabilities of this detector to provide luminosity measurements are investigated. The number of detector hits is observed to scale linearly with collision multiplicity across the full range of expected multiplicities.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2018. , p. 166
Series
TRITA-SCI-FOU ; 2018:35
Keywords [en]
p p: colliding beams, Higgs particle: hadroproduction, Higgs particle: decay, cross section: measured, High energy physics: experimental, Timing detectors, p p: scattering, ATLAS, Cern LHC Coll
National Category
Subatomic Physics
Research subject
Physics
Identifiers
URN: urn:nbn:se:kth:diva-233886ISBN: 978-91-7729-923-3 (print)OAI: oai:DiVA.org:kth-233886DiVA, id: diva2:1244395
Public defence
2018-09-28, FP41, Roslagstullsbacken 33, Stockholm, 13:00 (English)
Opponent
Supervisors
Note

QC 20180903

Available from: 2018-09-03 Created: 2018-08-31 Last updated: 2018-09-03Bibliographically approved

Open Access in DiVA

fulltext(18361 kB)65 downloads
File information
File name FULLTEXT01.pdfFile size 18361 kBChecksum SHA-512
09a07073597a85182505ed4944474944101aa57def50a6b99081f989a1de048ac830c50ce4f721ebdc7f28cdd013a18faf924f589f41bbbd6ff99fef1a3b8987
Type fulltextMimetype application/pdf

Authority records BETA

Sidebo, P. Edvin

Search in DiVA

By author/editor
Sidebo, P. Edvin
By organisation
Particle and Astroparticle Physics
Subatomic Physics

Search outside of DiVA

GoogleGoogle Scholar
Total: 65 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 279 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf