Search results for " Collider"
showing 10 items of 1415 documents
The Upgrade of the ATLAS Level-1 Central Trigger Processor
2013
The ATLAS Level-1 Central Trigger Processor (CTP) combines information from calorimeter and muon trigger processors as well as other sources and makes the final Level-1 Accept (L1A) decision. Due to the increasing luminosity of the LHC and the growing demands of physics and monitoring placed on the ATLAS Level-1 trigger system, the current CTP has reached its design limits. Therefore and in order to provide some margin for future operation, the CTP will be upgraded during the LHC shutdown of 2013/14.
DEPFET Active Pixel Detectors for a Future Linear e(+)e(-) Collider
2013
arXiv:1212.2160v1.-- et al.
Global Trigger Technological Demonstrator for ATLAS Phase-II upgrade
2020
ATLAS detector at the LHC will undergo a major Phase-II upgrade for the High Luminosity LHC. The upgrade affects all major ATLAS systems, including the Trigger and Data Acquisition systems. As part of the Level-0 Trigger System, the Global Trigger uses full-granularity calorimeter cells to perform algorithms, refines the trigger objects and applies topological requirements. The Global Trigger uses a Global Common Module as the building block of its design. To achieve a high input and output bandwidth and substantial processing power, the Global Common Module will host the most advanced FPGAs and optical modules. In order to evaluate the new generation of optical modules and FPGAs running at…
Combination of Searches for Invisible Higgs Boson Decays with the ATLAS Experiment
2019
Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for H → invisible decays where H is produced according to the standard model via vector boson fusion, Z(ℓℓ)H, and W/Z(had)H, all performed with the ATLAS detector using 36.1 fb⁻¹ of pp collisions at a center-of-mass energy of √s = 13 TeV at the LHC. In combination with the results at √s = 7 and 8 TeV, an exclusion limit on the H → invisible branching ratio of 0.26(0.17-0.05+0.07) at 95% confidence level is observed (expected).
Anomalous quartic gauge boson couplings at hadron colliders
2000
We analyze the potential of the Fermilab Tevatron and CERN Large Hadron Collider (LHC) to study anomalous quartic vector--boson interactions (photon photon Z Z) and (photon photon W+ W-). Working in the framework of SU(2)_L X U(1)_Y chiral Lagrangians, we study the production of photons pairs accompanied by (e+e-), (e nu), and jet pairs to impose bounds on these new couplings, taking into account the unitarity constraints. We compare our findings with the indirect limits coming from precision electroweak measurements as well as with presently available direct searches at LEPII. We show that the Tevatron Run II can provide limits on these quartic limits which are of the same order of magnitu…
Resolution of the ATLAS muon spectrometer monitored drift tubes in LHC Run 2
2019
The momentum measurement capability of the ATLAS muon spectrometer relies fundamentally on the intrinsic single-hit spatial resolution of the monitored drift tube precision tracking chambers. Optimal resolution is achieved with a dedicated calibration program that addresses the specific operating conditions of the 354 000 high-pressure drift tubes in the spectrometer. The calibrations consist of a set of timing offsets and drift time to drift distance transfer relations, and result in chamber resolution functions. This paper describes novel algorithms to obtain precision calibrations from data collected by ATLAS in LHC Run 2 and from a gas monitoring chamber, deployed in a dedicated gas fac…
Centrality-dependent forward J/ψ production in high energy proton-nucleus collisions
2016
Forward $J/\psi$ production and suppression in high energy proton-nucleus collisions can be an important probe of gluon saturation. In an earlier work we studied this process in the Color Glass Condensate framework and showed that using the Glauber approach to extrapolate the dipole cross section of a proton to a nucleus leads to results closer to experimental data than previous calculations in this framework. Here we investigate the centrality dependence of the nuclear suppression in this model and show a comparison of our results with recent LHC data.
Electron and photon energy calibration with the ATLAS detector using 2015-2016 LHC proton-proton collision data
2019
Artículo realizado por muchos autores. Solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración y los autores que firman como pertenecientes a la UAM
Monopolium production from photon fusion at the Large Hadron Collider
2008
6 pages, 6 figures.-- PACS nrs.: 14.80.Hv; 95.30.Cq; 98.70.-f; 98.80.-k.-- Printed version published Aug 2009.-- ArXiv pre-print available at: http://arxiv.org/abs/0809.0272
Observation of Higgs boson production in association with a top quark pair at the LHC with the ATLAS detector
2018
Physics letters / B 784, 173 - 191 (2018). doi:10.1016/j.physletb.2018.07.035