Author: ATLAS Collaboration CERN Publisher: ISBN: Category : Languages : en Pages : 0
Book Description
Abstract: The performance of the ATLAS Inner Detector alignment has been studied using pp collision data at s√=13TeV collected by the ATLAS experiment during Run 2 (2015-2018) of the Large Hadron Collider (LHC). The goal of the detector alignment is to determine the detector geometry as accurately as possible and correct for time-dependent movements. The Inner Detector alignment is based on the minimization of track-hit residuals in a sequence of hierarchical levels, from global mechanical assembly structures to local sensors. Subsequent levels have increasing numbers of degrees of freedom; in total there are almost 750,000. The alignment determines detector geometry on both short and long timescales, where short timescales describe movements within an LHC fill. The performance and possible track parameter biases originating from systematic detector deformations are evaluated. Momentum biases are studied using resonances decaying to muons or to electrons. The residual sagitta bias and momentum scale bias after alignment are reduced to less than ∼0.1 TeV−1 and 0.9×10−3, respectively. Impact parameter biases are also evaluated using tracks within jets
Author: Christian W. Fabjan Publisher: Springer Nature ISBN: 3030353184 Category : Elementary particles (Physics). Languages : en Pages : 1083
Book Description
This second open access volume of the handbook series deals with detectors, large experimental facilities and data handling, both for accelerator and non-accelerator based experiments. It also covers applications in medicine and life sciences. A joint CERN-Springer initiative, the "Particle Physics Reference Library" provides revised and updated contributions based on previously published material in the well-known Landolt-Boernstein series on particle physics, accelerators and detectors (volumes 21A, B1,B2,C), which took stock of the field approximately one decade ago. Central to this new initiative is publication under full open access
Author: Zhen-An Liu Publisher: Springer ISBN: 9811313164 Category : Technology & Engineering Languages : en Pages : 445
Book Description
These two volumes present the proceedings of the International Conference on Technology and Instrumentation in Particle Physics 2017 (TIPP2017), which was held in Beijing, China from 22 to 26 May 2017. Gathering selected articles on the basis of their quality and originality, it highlights the latest developments and research trends in detectors and instrumentation for all branches of particle physics, particle astrophysics and closely related fields. This is the second volume, and focuses on the main themes Astrophysics and space instrumentation, Front-end electronics and fast data transmission, Trigger and data acquisition systems, Machine detectors, Interfaces and beam instrumentation, Backend readout structures and embedded systems, Medical imaging, and Security & other applications. The TIPP2017 is the fourth in a series of international conferences on detectors and instrumentation, held under the auspices of the International Union of Pure and Applied Physics (IUPAP). The event brings together experts from the scientific and industrial communities to discuss their current efforts and plan for the future. The conference’s aim is to provide a stimulating atmosphere for scientists and engineers from around the world.
Author: Kurt Brendlinger Publisher: Springer ISBN: 3319739301 Category : Science Languages : en Pages : 261
Book Description
This thesis presents two production cross-section measurements of pairs of massive bosons using final states with leptons, made with the ATLAS detector at the Large Hadron Collider. The first measurement, performed using data collected in 2012 at center-of-mass energy √ s = 8 TeV, is the first fiducial and differential cross-section measurement of the production of the Higgs Boson when it decays to four charged leptons (electrons or muons). The second measurement is the first fiducial and inclusive production cross-section measurement of WZ pairs at center-of-mass energy √ s = 13 TeV using final states with three charged leptons. A significant portion of the thesis focuses on the methods used to identify electrons from massive boson decay—important for many flagship measurements—and on assessing the efficiency of these particle identification techniques. The chapter discussing the WZ pair cross-section measurement provides a detailed example of an estimate of lepton background in the context of an analysis with three leptons in the final state.
Author: Lydia Audrey Beresford Publisher: Springer ISBN: 331997520X Category : Science Languages : en Pages : 175
Book Description
This book addresses one of the most intriguing mysteries of our universe: the nature of dark matter. The results presented here mark a significant and substantial contribution to the search for new physics, in particular for new particles that couple to dark matter. The first analysis presented is a search for heavy new particles that decay into pairs of hadronic jets (dijets). This pioneering analysis explores unprecedented dijet invariant masses, reaching nearly 7 TeV, and sets constraints on several important new physics models. The two subsequent analyses focus on the difficult low dijet mass region, down to 200 GeV, and employ a novel technique to efficiently gather low-mass dijet events. The results of these analyses transcend the long-standing constraints on dark matter mediator particles set by several existing experiments.
Author: Publisher: ISBN: Category : Languages : en Pages : 13
Book Description
The ATLAS experiment is a multi-purpose particle detector that will study high-energy particle collisions produced by the Large Hadron Collider. For the reconstruction of charged particles, and their production and their decay vertices, ATLAS is equipped with a sophisticated tracking system, unprecedented in size and complexity. Full exploitation of both the Inner Detector and the muon spectrometer requires an accurate alignment. The challenge of aligning the ATLAS tracking devices is discussed, and the ATLAS alignment strategy is presented and illustrated with both data and Monte Carlo results.
Author: Brian Moser Publisher: Springer Nature ISBN: 3031394429 Category : Science Languages : en Pages : 250
Book Description
Precision measurements of the Higgs boson’s properties are a powerful tool to look for deviations from the predictions of the Standard Model (SM) of particle physics. The 139/fb of proton-proton collision data which have been collected by the ATLAS experiment during Run 2 of the LHC, offer an opportunity to investigate rare Higgs-boson topologies, which are particularly sensitive to new physics scenarios but experimentally difficult to access. Several such measurements, which target Higgs-boson decays to heavy-flavour quarks, as well as their combinations are presented in this thesis. A novel analysis that measures Higgs-boson production in association with a heavy vector boson V (VH, with V=W,Z) at high energies is presented. Dedicated Higgs-boson reconstruction techniques are applied to reconstruct the highly Lorentz-boosted Higgs-boson decays into pairs of bottom quarks. The measurement is subsequently combined with a VH cross-section measurement at low and intermediate pT(V) to provide a differential cross-section measurement in kinematic fiducial volumes over the largest possible pT(V) range. All cross-section measurements agree with the SM predictions within relative uncertainties that range from 30% to 300%. The results are furthermore interpreted as limits on the parameters of a SM effective field theory. Finally, a combination of measurements of Higgs decays to heavy-flavour quarks is used to experimentally determine that the Higgs-boson coupling to charm quarks is weaker than to bottom quarks, as predicted by the SM. The target audience for the thesis are physicists and physics students, in particular those with a background in high energy physics.
Author: John Alison Publisher: Springer ISBN: 331910344X Category : Science Languages : en Pages : 314
Book Description
The research presented here includes important contributions on the commissioning of the ATLAS experiment and the discovery of the Higgs boson. The thesis describes essential work on the alignment of the inner tracker during the commissioning of the experiment and development of the electron identification algorithm. The subsequent analysis focuses on the search for the Higgs boson in the WW channel, including the development of a method to model the critical W+jet background. In addition, the thesis provides excellent introductions, suitable for non-specialists, to Higgs physics, to the LHC, and to the ATLAS experiment.
Author: ATLAS Collaboration CERN
Author: Danny Hindson
Author: Adrian Francis Fox-Murphy
Author: Christian W. Fabjan
Author: Zhen-An Liu
Author: Kurt Brendlinger
Author: Lydia Audrey Beresford
Author: 
Author: Brian Moser
Author: John Alison