Browsing by Subject "Nuclear"

Now showing 1 - 4 of 4
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    Measurement of the W ± Z boson pair-production cross section in pp collisions at s = 13  TeV with the ATLAS detector
    (2016) Aaboud, M; Aad, G; Abbott, B; Abdallah, J; Abdinov, O; Abeloos, B; Aben, R; AbouZeid, O S; Abraham, N L; Abramowicz, H; Abreu, H; Abreu, R; Abulaiti, Y; Acharya, B S; Adamczyk, L; Adams, D L; Adelman, J; Adomeit, S; Adye, T; Affolder, A A; Agatonovic-Jovin, T; Agricola, J; Aguilar-Saavedra, J A; Ahlen, S P; Ahmadov, F; Aielli, G; Akerstedt, H; Åkesson, T P A; Akimov, A V; Alberghi, G L; Albert, J; Albrand, S
    Here, the production of W ±Z events in proton–proton collisions at a centre-of-mass energy of 13 TeV13 TeV is measured with the ATLAS detector at the LHC. The collected data correspond to an integrated luminosity of 3.2 fb –1. The W ±Z candidates are reconstructed using leptonic decays of the gauge bosons into electrons or muons.
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    Open Access
    Measurement of the cross section for inclusive isolated-photon production in pp collisions at s√=13 TeV using the ATLAS detector
    (2017) Aaboud, M; Aad, G; Abbott, B; Abdallah, J; Abdinov, O; Abeloos, B; Abidi, S H; AbouZeid, O S; Abraham, N L; Abramowicz, H; Abreu, H; Abreu, R; Abulaiti, Y; Acharya, B S; Adachi, S; Adamczyk, L; Adams, D L; Adelman, J; Adersberger, M; Adye, T; Affolder, A A; Agatonovic-Jovin, T; Agheorghiesei, C; Aguilar-Saavedra, J A; Ahlen, S P; Ahmadov, F; Aielli, G; Akatsuka, S; Akerstedt, H; Åkesson, T P A; Akimov, A V; Alberghi, G L
    Here, inclusive isolated-photon production in pp collisions at a centre-of-mass energy of 13TeV is studied with the ATLAS detector at the LHC using a data set with an integrated luminosity of 3.2fb -1. The cross section is measured as a function of the photon transverse energy above 125GeV in different regions of photon pseudorapidity. Next-to-leading-order perturbative QCD and Monte Carlo event-generator predictions are compared to the cross-section measurements and provide an adequate description of the data.
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    Open Access
    Measurement of the total cross section from elastic scattering in pp collisions at s = 8   TeV with the ATLAS detector
    (2016) Aaboud, M; Aad, G; Abbott, B; Abdallah, J; Abdinov, O; Abeloos, B; Aben, R; AbouZeid, O S; Abraham, N L; Abramowicz, H; Abreu, H; Abreu, R; Abulaiti, Y; Acharya, B S; Adachi, S; Adamczyk, L; Adams, D L; Adelman, J; Adomeit, S; Adye, T; Affolder, A A; Agatonovic-Jovin, T; Agricola, J; Aguilar-Saavedra, J A; Ahlen, S P; Ahmadov, F; Aielli, G; Akerstedt, H; Åkesson, T P A; Akimov, A V; Alberghi, G L; Albert, J
    A measurement of the total $pp$ cross section at the LHC at $sqrt{s}=8$ TeV is presented. An integrated luminosity of $500$ $mu$b${-1}$ was accumulated in a special run with high-$beta{star}$ beam optics to measure the differential elastic cross section as a function of the Mandelstam momentum transfer variable $t$. The measurement is performed with the ALFA sub-detector of ATLAS. Using a fit to the differential elastic cross section in the $-t$ range from $0.014$ GeV$2$ to $0.1$ GeV$2$ to extrapolate $trightarrow 0$, the total cross section, $sigma_{mathrm{tot}}(pprightarrow X)$, is measured via the optical theorem to be: $sigma_{mathrm{tot}}(pprightarrow X) = {96.07} ; pm 0.18 ; ({{stat.}}) pm 0.85 ; ({{exp.}}) pm 0.31 ; ({extr.}) ; {mb} ;,$ where the first error is statistical, the second accounts for all experimental systematic uncertainties and the last is related to uncertainties in the extrapolation $trightarrow 0$. In addition, the slope of the exponential function describing the elastic cross section at small $t$ is determined to be $B = 19.74 pm 0.05 ; ({{stat.}}) pm 0.23 ; ({{syst.}}) ; {GeV}{-2}$.
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    Open Access
    Search for heavy resonances decaying to a Z boson and a photon in pp collisions at √s = 13 TeV with the ATLAS detector
    (2017) Aaboud, M; Aad, G; Abbott, B; Abdallah, J; Abdinov, O; Abeloos, B; Aben, R; AbouZeid, O S; Abraham, N L; Abramowicz, H; Abreu, H; Abreu, R; Abulaiti, Y; Acharya, B S; Adachi, S; Adamczyk, L; Adams, D L; Adelman, J; Adomeit, S; Adye, T; Affolder, A A; Agatonovic-Jovin, T; Agricola, J; Aguilar-Saavedra, J A; Ahlen, S P; Ahmadov, F; Aielli, G; Akerstedt, H; Åkesson, T P A; Akimov, A V; Alberghi, G L; Albert, J
    This Letter presents a search for new resonances with mass larger than 250 GeV, decaying to a Z boson and a photon. The dataset consists of an integrated luminosity of 3.2 fb−1 of pp collisions collected at √s = 13 TeV with the ATLAS detector at the Large Hadron Collider. The Z bosons are identified through their decays either to charged, light, lepton pairs (e+e−, μ+μ−) or to hadrons. The data are found to be consistent with the expected background in the whole mass range investigated and upper limits are set on the production cross section times decay branching ratio to Zγ of a narrow scalar boson with mass between 250 GeV and 2.75 TeV.