0000000000359902
AUTHOR
S. Yu Sivoklokov
Luminosity determination in pp collisions at s=7 TeV using the ATLAS detector at the LHC
Measurements of luminosity obtained using the ATLAS detector during early running of the Large Hadron Collider (LHC) at s√=7 TeV are presented. The luminosity is independently determined using several detectors and multiple algorithms, each having different acceptances, systematic uncertainties and sensitivity to background. The ratios of the luminosities obtained from these methods are monitored as a function of time and of μ, the average number of inelastic interactions per bunch crossing. Residual time- and μ-dependence between the methods is less than 2% for 0<μ<2.5. Absolute luminosity calibrations, performed using beam separation scans, have a common systematic uncertainty of ±11%, do…
Search for dark matter candidates and large extra dimensions in events with a jet and missing transverse momentum with the ATLAS detector
A search for new phenomena in events with a high-energy jet and large missing transverse momentum is performed using data from proton-proton collisions at √s = 7 TeV with the ATLAS experiment at the Large Hadron Collider. Four kinematic regions are explored using a dataset corresponding to an integrated luminosity of 4.7 fb[superscript −1]. No excess of events beyond expectations from Standard Model processes is observed, and limits are set on large extra dimensions and the pair production of dark matter particles.
Observation and Measurement of Forward Proton Scattering in Association with Lepton Pairs Produced via the Photon Fusion Mechanism at ATLAS
The observation of forward proton scattering in association with lepton pairs (eþe− þ p or μþμ− þ p) produced via photon fusion is presented. The scattered proton is detected by the ATLAS Forward Proton spectrometer, while the leptons are reconstructed by the central ATLAS detector. Proton-proton collision data recorded in 2017 at a center-of-mass energy of ffiffiffi s p ¼ 13 TeV are analyzed, corresponding to an integrated luminosity of 14.6 fb−1. A total of 57 (123) candidates in the ee þ p (μμ þ p) final state are selected, allowing the background-only hypothesis to be rejected with a significance exceeding 5 standard deviations in each channel. Proton-tagging techniques are introduced f…
Measurement of photon?jet transverse momentum correlations in 5.02 TeV Pb + Pb and pp collisions with ATLAS
Jets created in association with a photon can be used as a calibrated probe to study energy loss in the medium created in nuclear collisions. Measurements of the transverse momentum balance between isolated photons and inclusive jets are presented using integrated luminosities of 0.49 nb−1 of Pb + Pb collision data at TeV and 25 pb−1 of pp collision data at TeV recorded with the ATLAS detector at the LHC. Photons with transverse momentum GeV and are paired with all jets in the event that have GeV and pseudorapidity . The transverse momentum balance given by the jet-to-photon ratio, , is measured for pairs with azimuthal opening angle . Distributions of the per-photon jet yield as a function…
Search for dark matter in events with heavy quarks and missing transverse momentum in [Formula: see text] collisions with the ATLAS detector.
This article reports on a search for dark matter pair production in association with bottom or top quarks in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$20.3 \mathrm {~fb}^{-1}$$\end{document}20.3fb-1 of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$pp$$\end{document}pp collisions collected at \documentclass[12pt]{minimal} \use…