Measurements of the yield and nuclear modification factor, $R_\mathrm{ AA}$, for inclusive jet production are performed using 0.49 nb$^{-1}$ of Pb+Pb data at $\sqrt{s_\mathrm{NN}} = 5.02$ TeV and 25 pb$^{-1}$ of $pp$ data at $\sqrt{s}=5.02$ TeV with the ATLAS detector at the LHC. Jets are reconstructed with the anti-$k_t$ algorithm with radius parameter $R=0.4$ and are measured over the transverse momentum range of 40-1000 GeV in six rapidity intervals covering $|y|<2.8$. The magnitude of $R_\mathrm{ AA}$ increases with increasing jet transverse momentum, reaching a value of approximately 0.6 at 1 TeV in the most central collisions. The magnitude of $R_\mathrm{ AA}$ also increases towards peripheral collisions. The value of $R_\mathrm{ AA}$ is independent of rapidity at low jet transverse momenta, but it is observed to decrease with increasing rapidity at high transverse momenta.
The ⟨TAA⟩ and ⟨Npart⟩ values and their uncertainties in each centrality bin.
No description provided.
No description provided.
The production cross-sections of $\Upsilon(1S)$, $\Upsilon(2S)$ and $\Upsilon(3S)$ mesons in proton-proton collisions at $\sqrt{s}$= 13 TeV are measured with a data sample corresponding to an integrated luminosity of $277 \pm 11$ $\rm pb^{-1}$ recorded by the LHCb experiment in 2015. The $\Upsilon$ mesons are reconstructed in the decay mode $\Upsilon\to\mu^{+}\mu^{-}$. The differential production cross-sections times the dimuon branching fractions are measured as a function of the $\Upsilon$ transverse momentum, $p_{\rm T}$, and rapidity, $y$, over the range $0 < p_{\rm T}< 30$ GeV/c and $2.0 < y < 4.5$. The ratios of the cross-sections with respect to the LHCb measurement at $\sqrt{s}$= 8 TeV are also determined. The measurements are compared with theoretical predictions based on NRQCD.
Double-differential cross-sections times dimuon branching fraction in different bins of $p_T$ and $y$ for $\Upsilon$(1S) (in pb). The first uncertainty is statistical and the second is systematic.
Double-differential cross-sections times dimuon branching fraction in different bins of $p_T$ and $y$ for $\Upsilon$(2S) (in pb). The first uncertainty is statistical and the second is systematic.
Double-differential cross-sections times dimuon branching fraction in different bins of $p_T$ and $y$ for $\Upsilon$(3S) (in pb). The first uncertainty is statistical and the second is systematic.
This paper presents a measurement of the double-differential cross section for the Drell-Yan $Z/\gamma^{*} \rightarrow \ell^{+} \ell^{-}$ and photon-induced $\gamma\gamma \rightarrow \ell^{+} \ell^{-}$ processes where $\ell$ is an electron or muon. The measurement is performed for invariant masses of the lepton pairs, $m_{\ell\ell}$, between 116 GeV and 1500 GeV, using a sample of 20.3 fb$^{-1}$ of pp collisions data at centre-of-mass energy of $\sqrt{s}$ = 8 TeV collected by the ATLAS detector at the LHC in 2012. The data are presented double differentially in invariant mass and absolute dilepton rapidity as well as in invariant mass and absolute pseudorapidity separation of the lepton pair. The single-differential cross section as a function of $m_{\ell\ell}$ is also reported. The electron and muon channel measurements are combined and a total experimental precision of better than 1% is achieved at low $m_{\ell\ell}$. A comparison to next-to-next-to-leading order perturbative QCD predictions using several recent parton distribution functions and including next-to-leading order electroweak effects indicates the potential of the data to constrain parton distribution functions. In particular, a large impact of the data on the photon PDF is demonstrated.
The combined Born-level single-differential cross section as a function of invariant mass. The measurements are listed together with the statistical and systematic uncertainties. The systematic uncertainties are separated into one uncorrelated, 35 correlated sources and the luminosity uncertainty. The sign of the uncertainty corresponds to a one standard deviation upward shift of the uncertainty source, where +/- means "+" and -/+ means "-".
The combined Born-level double-differential cross section as a function of invariant mass and absolute rapidity. The measurements are listed together with the statistical and systematic uncertainties. The systematic uncertainties are separated into one uncorrelated, 35 correlated sources and the luminosity uncertainty. The sign of the uncertainty corresponds to a one standard deviation upward shift of the uncertainty source, where +/- means "+" and -/+ means "-".
The combined Born-level double-differential cross section as a function of invariant mass and absolute pseudorapidity separation of the leptons. The measurements are listed together with the statistical and systematic uncertainties. The systematic uncertainties are separated into one uncorrelated, 35 correlated sources and the luminosity uncertainty. The sign of the uncertainty corresponds to a one standard deviation upward shift of the uncertainty source, where +/- means "+" and -/+ means "-".
The production rates of prompt and non-prompt $J/\psi$ and $\psi(2\mathrm{S})$ mesons are measured using 2.1 $fb^{-1}$ and 11.4 $fb^{-1}$ of data collected with the ATLAS experiment at the LHC, in proton-proton collisions at $\sqrt{s}=7$ and 8 TeV respectively. Production cross-sections for both prompt and non-prompt production sources, ratios of $\psi(2\mathrm{S})$ to $J/\psi$ production, and fractions of non-prompt to inclusive production for $J/\psi$ and $\psi(2\mathrm{S})$ are measured double-differentially as a function of meson $p_{T}$ and rapidity. These measurements are made in a restricted fiducial volume and also corrected for geometrical acceptance after which they are compared to a variety of theoretical predictions.
Summary of results for cross-section of prompt $J/\psi$ decaying to a muon pair for 7 TeV data in nb/GeV. Uncertainties are statistical and systematic, respectively.
Summary of results for cross-section of prompt $J/\psi$ decaying to a muon pair for 8 TeV data in nb/GeV. Uncertainties are statistical and systematic, respectively.
Summary of results for cross-section of non-prompt $J/\psi$ decaying to a muon pair for 7 TeV data in nb/GeV. Uncertainties are statistical and systematic, respectively.
The production of $\Upsilon$ mesons in $pp$ collisions at $\sqrt=7$ and $8\,\mathrm{TeV}$ is studied with the LHCb detector using data samples corresponding to an integrated luminosity of $1\,\mathrm{fb}^{-1}$ and $2\,\mathrm{fb}^{-1}$ respectively. The production cross-sections and ratios of cross-sections are measured as functions of the meson transverse momentum $p_T$ and rapidity $y$, for $p_T<30\,\mathrm{GeV}/c$} and $2.0
Double-differential cross-section $\mathrm{d}^2 \sigma ( pp \to ( \Upsilon \to \mu^+ \mu^- ) X ) / \mathrm{d} p_T/\mathrm{d}y$ [pb/(GeV/$c$)] for $2.0 < y < 2.5$.
Double-differential cross-section $\mathrm{d}^2 \sigma ( pp \to ( \Upsilon \to \mu^+ \mu^- ) X ) / \mathrm{d} p_T/\mathrm{d}y$ [pb/(GeV/$c$)] for $2.0 < y < 2.5$.
Double-differential cross-section $\mathrm{d}^2 \sigma ( pp \to ( \Upsilon \to \mu^+ \mu^- ) X ) / \mathrm{d} p_T/\mathrm{d}y$ [pb/(GeV/$c$)].
The production of $J/\psi$ mesons in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}=13$ TeV is studied with the \lhcb detector. Cross-section measurements are performed as a function of the transverse momentum $p_\mathrm{T}$ and the rapidity $y$ of the $J/\psi$ meson in the region $p_\mathrm{T}<14\mathrm{GeV}/c$ and $2.0
Double differential cross-section for prompt $J/\psi$ mesons as a function of $p_\perp$ in bins of $y$. The first uncertainties are statistical, the second are the correlated systematic uncertainties shared between bins and the last are the uncorrelated systematic uncertainties.
Double differential cross-section for $J/\psi$-from-$b$ mesons as a function of $p_\perp$ in bins of $y$. The first uncertainties are statistical, the second are the correlated systematic uncertainties shared between bins and the last are the uncorrelated systematic uncertainties.
The fraction of $J/\psi$-from-$b$ mesons (in %) in bins of the $J/\psi$ $p_\perp$ and $y$. The uncertainties are statistical only. The systematic uncertainties are negligible.
Measurements of differential cross-sections for $J/\psi$ production in p+Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV at the LHC with the ATLAS detector are presented. The data set used corresponds to an integrated luminosity of 28.1 nb$^{-1}$. The $J/\psi$ mesons are reconstructed in the dimuon decay channel over the transverse momentum range $8
Measured non-prompt fraction.
Measured non-prompt fraction.
Measured prompt J/psi differential cross-section multiplied by branching ratio. The first systematic uncertainty is the combined systematic uncertainty excluding luminosity, the second is the luminosity.
Measurements of inclusive jet production are performed in $pp$ and Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV with the ATLAS detector at the LHC, corresponding to integrated luminosities of 4.0 $\mathrm{pb}^{-1}$ and 0.14 $\mathrm{nb}^{-1}$, respectively. The jets are identified with the anti-$k_t$ algorithm with $R=0.4$, and the spectra are measured over the kinematic range of jet transverse momentum $32 < p_{\mathrm{T}} < 500$ GeV, and absolute rapidity $|y| < 2.1$ and as a function of collision centrality. The nuclear modification factor, $R_{\mathrm{AA}}$, is evaluated and jets are found to be suppressed by approximately a factor of two in central collisions compared to $pp$ collisions. The $R_{\mathrm{AA}}$ shows a slight increase with $p_{\mathrm{T}}$ and no significant variation with rapidity.
The $\langle T_{\mathrm{AA}} \rangle $ and $\langle N_{\mathrm{part}} \rangle$ values and their uncertainties in each centrality bin.
No description provided.
No description provided.
Double-differential three-jet production cross-sections are measured in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} = 7$ TeV using the ATLAS detector at the Large Hadron Collider. The measurements are presented as a function of the three-jet mass $(m_{jjj})$, in bins of the sum of the absolute rapidity separations between the three leading jets $(|Y^\ast|)$. Invariant masses extending up to 5 TeV are reached for $8< |Y^\ast| < 10$. These measurements use a sample of data recorded using the ATLAS detector in 2011, which corresponds to an integrated luminosity of 4.51 fb$^{-1}$. Jets are identified using the anti-$k_t$ algorithm with two different jet radius parameters, R=0.4 and R=0.6. The dominant uncertainty in these measurements comes from the jet energy scale. Next-to-leading-order QCD calculations corrected to account for non-perturbative effects are compared to the measurements. Good agreement is found between the data and the theoretical predictions based on most of the available sets of parton distribution functions, over the full kinematic range, covering almost seven orders of magnitude in the measured cross-section values.
Measured three-jet double-differential cross sections as a function of M(3JET) in |Y*|<2 for anti-kt R=0.4 jets. The three columns correspond to nominal, stronger or weaker correlations between jet energy scale uncertainty components.
Measured three-jet double-differential cross sections as a function of M(3JET) in 2<=|Y*|<4 for anti-kt R=0.4 jets. The three columns correspond to nominal, stronger or weaker correlations between jet energy scale uncertainty components.
Measured three-jet double-differential cross sections as a function of M(3JET) in 4<=|Y*|<6 for anti-kt R=0.4 jets. The three columns correspond to nominal, stronger or weaker correlations between jet energy scale uncertainty components.
The inclusive jet cross-section is measured in proton-proton collisions at a centre-of-mass energy of 7 TeV using a data set corresponding to an integrated luminosity of 4.5 fb$^{-1}$ collected with the ATLAS detector at the Large Hadron Collider in 2011. Jets are identified using the anti-$k_t$ algorithm with radius parameter values of 0.4 and 0.6. The double-differential cross-sections are presented as a function of the jet transverse momentum and the jet rapidity, covering jet transverse momenta from 100 GeV to 2 TeV. Next-to-leading-order QCD calculations corrected for non-perturbative effects and electroweak effects, as well as Monte Carlo simulations with next-to-leading-order matrix elements interfaced to parton showering, are compared to the measured cross-sections. A quantitative comparison of the measured cross-sections to the QCD calculations using several sets of parton distribution functions is performed.
Measured double-differential inclusive-jet cross section for the range 0.0 <= |y| < 0.5 and for anti-kT jets with radius parameter R = 0.4. It is based on the data sample of proton-proton collisions at 7 TeV of centre-of-mass energy collected in 2011 by the ATLAS experiment at the LHC. The data sample corresponds to the integrated luminosity of 4.5 fb^-1. The statistical uncertainties arising from data and MC simulation have been combined. All the components of the systematic uncertainty are shown. They are: all the components of the jet energy scale uncertainty (jesX), the uncertainty of the jet energy resolution (jer), the uncertainty of the jet angular resolution (jar), the uncertainty of data unfolding (unfold), the uncertainty of the jet quality selection (qual), the luminosity uncertainty (lumi). All the components are assumed to be independent of each other. Each component is assumed to be fully correlated in pT and eta. Concerning the shape of the different components, Gaussian distribution assumption works for most of them. The three columns correspond to three different sets of the systematic uncertainty built with nominal, stronger or weaker assumptions on correlations between the jet energy scale uncertainty components. For more information on the systematic uncertainties, see the reference paper.
Measured double-differential inclusive-jet cross section for the range 0.5 <= |y| < 1.0 and for anti-kT jets with radius parameter R = 0.4. It is based on the data sample of proton-proton collisions at 7 TeV of centre-of-mass energy collected in 2011 by the ATLAS experiment at the LHC. The data sample corresponds to the integrated luminosity of 4.5 fb^-1. The statistical uncertainties arising from data and MC simulation have been combined. All the components of the systematic uncertainty are shown. They are: all the components of the jet energy scale uncertainty (jesX), the uncertainty of the jet energy resolution (jer), the uncertainty of the jet angular resolution (jar), the uncertainty of data unfolding (unfold), the uncertainty of the jet quality selection (qual), the luminosity uncertainty (lumi). All the components are assumed to be independent of each other. Each component is assumed to be fully correlated in pT and eta. Concerning the shape of the different components, Gaussian distribution assumption works for most of them. The three columns correspond to three different sets of the systematic uncertainty built with nominal, stronger or weaker assumptions on correlations between the jet energy scale uncertainty components. For more information on the systematic uncertainties, see the reference paper.
Measured double-differential inclusive-jet cross section for the range 1.0 <= |y| < 1.5 and for anti-kT jets with radius parameter R = 0.4. It is based on the data sample of proton-proton collisions at 7 TeV of centre-of-mass energy collected in 2011 by the ATLAS experiment at the LHC. The data sample corresponds to the integrated luminosity of 4.5 fb^-1. The statistical uncertainties arising from data and MC simulation have been combined. All the components of the systematic uncertainty are shown. They are: all the components of the jet energy scale uncertainty (jesX), the uncertainty of the jet energy resolution (jer), the uncertainty of the jet angular resolution (jar), the uncertainty of data unfolding (unfold), the uncertainty of the jet quality selection (qual), the luminosity uncertainty (lumi). All the components are assumed to be independent of each other. Each component is assumed to be fully correlated in pT and eta. Concerning the shape of the different components, Gaussian distribution assumption works for most of them. The three columns correspond to three different sets of the systematic uncertainty built with nominal, stronger or weaker assumptions on correlations between the jet energy scale uncertainty components. For more information on the systematic uncertainties, see the reference paper.
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