Centrality dependence of J/$\psi$ and $\psi$(2S) production and nuclear modification in p-Pb collisions at $\sqrt{s_{\rm NN}} =$ 8.16 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
JHEP 02 (2021) 002, 2021.
Inspire Record 1811102 DOI 10.17182/hepdata.100166

The inclusive production of the J/$\psi$ and $\psi$(2S) charmonium states is studied as a function of centrality in p-Pb collisions at a centre-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}} = 8.16$ TeV at the LHC. The measurement is performed in the dimuon decay channel with the ALICE apparatus in the centre-of-mass rapidity intervals $-4.46 < y_{\rm cms} < -2.96$ (Pb-going direction) and $2.03 < y_{\rm cms} < 3.53$ (p-going direction), down to zero transverse momentum ($p_{\rm T}$). The J/$\psi$ and $\psi$(2S) production cross sections are evaluated as a function of the collision centrality, estimated through the energy deposited in the zero degree calorimeter located in the Pb-going direction. The $p_{\rm T}$-differential J/$\psi$ production cross section is measured at backward and forward rapidity for several centrality classes, together with the corresponding average $\langle p_{\rm T} \rangle$ and $\langle p^{2}_{\rm T} \rangle$ values. The nuclear effects affecting the production of both charmonium states are studied using the nuclear modification factor. In the p-going direction, a suppression of the production of both charmonium states is observed, which seems to increase from peripheral to central collisions. In the Pb-going direction, however, the centrality dependence is different for the two states: the nuclear modification factor of the J/$\psi$ increases from below unity in peripheral collisions to above unity in central collisions, while for the $\psi$(2S) it stays below or consistent with unity for all centralities with no significant centrality dependence. The results are compared with measurements in p-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV and no significant dependence on the energy of the collision is observed. Finally, the results are compared with theoretical models implementing various nuclear matter effects.

22 data tables

The $p_{\rm T}$-differential inclusive J/$\psi$ cross sections for six centrality classes at backward ($-4.46 < y_{\rm cms} < -2.96$) centre-of-mass rapidity. The first uncertainty is statistical, the second one and the third ones are the uncorrelated and correlated systematic uncertainties, respectively. The third uncertainty is fully correlated over $p_{\rm T}$.

The $p_{\rm T}$-differential inclusive J/$\psi$ cross sections for six centrality classes at forward ($2.03 < y_{\rm cms} < 3.53$) centre-of-mass rapidity. The first uncertainty is statistical, the second one and the third ones are the uncorrelated and correlated systematic uncertainties, respectively. The third uncertainty is fully correlated over $p_{\rm T}$.

The values of $\langle p_{\rm T} \rangle$ and $\langle p^{2}_{\rm T} \rangle$ for six centrality classes at backward ($-4.46 < y_{\rm cms} < -2.96$) and forward ($2.03 < y_{\rm cms} < 3.53$) centre-of-mass rapidity. The first uncertainty is statistical, the second one is the systematic uncertainty.

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Z-boson production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=8.16$ TeV and Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
JHEP 09 (2020) 076, 2020.
Inspire Record 1797444 DOI 10.17182/hepdata.97372

Measurement of Z-boson production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=8.16$ TeV and Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV is reported. It is performed in the dimuon decay channel, through the detection of muons with pseudorapidity $-4 < \eta_{\mu} < -2.5$ and transverse momentum $p_{\rm T}^{\mu} > 20$ GeV/$c$ in the laboratory frame. The invariant yield and nuclear modification factor are measured for opposite-sign dimuons with invariant mass $60 < m^{\mu\mu} < 120$ GeV$c^2$ and rapidity $2.5 < y_{cms}^{\mu\mu} < 4$. They are presented as a function of rapidity and, for the Pb-Pb collisions, of centrality as well. The results are compared with theoretical calculations, both with and without nuclear modifications to the Parton Distribution Functions (PDFs). In p-Pb collisions the center-of-mass frame is boosted with respect to the laboratory frame, and the measurements cover the backward ($-4.46< y_{cms}^{\mu\mu}<-2.96$) and forward ($2.03< y_{cms}^{\mu\mu}<3.53$) rapidity regions. For the p-Pb collisions, the results are consistent within experimental and theoretical uncertainties with calculations that include both free-nucleon and nuclear-modified PDFs. For the Pb-Pb collisions, a $3.4\sigma$ deviation is seen in the integrated yield between the data and calculations based on the free-nucleon PDFs, while good agreement is found once nuclear modifications are considered.

5 data tables

Differential fiducial cross section in p-Pb

Integrated fiducial invariant yield in Pb-Pb

Rapidity differential fiducial invariant yield in Pb-Pb

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Production of light-flavor hadrons in pp collisions at $\sqrt{s}$ = 7 and $\sqrt{s}$ = 13 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
Eur.Phys.J.C 81 (2021) 256, 2021.
Inspire Record 1797443 DOI 10.17182/hepdata.100303

The production of $\pi^{\pm}$, $\rm{K}^{\pm}$, $\rm{K}^{0}_{S}$, $\rm{K}^{*}(892)^{0}$, $\rm{p}$, $\phi(1020)$, $\Lambda$, $\Xi^{-}$, $\Omega^{-}$, and their antiparticles was measured in inelastic proton-proton (pp) collisions at a center-of-mass energy of $\sqrt{s}$ = 13 TeV at midrapidity ($|y|<0.5$) as a function of transverse momentum ($p_{\rm{T}}$) using the ALICE detector at the CERN LHC. Furthermore, the single-particle $p_{\rm{T}}$ distributions of $\rm{K}^{0}_{S}$, $\Lambda$, and $\overline{\Lambda}$ in inelastic pp collisions at $\sqrt{s}$ = 7 TeV are reported here for the first time. The $p_{\rm{T}}$ distributions are studied at midrapidity within the transverse momentum range $0\leq p_{\rm{T}}\leq20$ GeV/$c$, depending on the particle species. The $p_{\rm{T}}$ spectra, integrated yields, and particle yield ratios are discussed as a function of collision energy and compared with measurements at lower $\sqrt{s}$ and with results from various general-purpose QCD-inspired Monte Carlo models. A hardening of the spectra at high $p_{\rm{T}}$ with increasing collision energy is observed, which is similar for all particle species under study. The transverse mass and $x_{\rm{T}}\equiv2p_{\rm{T}}/\sqrt{s}$ scaling properties of hadron production are also studied. As the collision energy increases from $\sqrt{s}$ = 7 to 13 TeV, the yields of non- and single-strange hadrons normalized to the pion yields remain approximately constant as a function of $\sqrt{s}$, while ratios for multi-strange hadrons indicate enhancements. The $p_{\rm{T}}$-differential cross sections of $\pi^{\pm}$, $\rm{K}^{\pm}$ and $\rm{p}$ ($\overline{\rm{p}}$) are compared with next-to-leading order perturbative QCD calculations, which are found to overestimate the cross sections for $\pi^{\pm}$ and $\rm{p}$ ($\overline{\rm{p}}$) at high $p_{\rm{T}}$.

47 data tables

Transverse momentum spectrum of $\pi^{+} + \pi^{-}$ measured at midrapidity ($|y|<0.5$) in inelastic pp collisions at $\sqrt{s}$ = 13 TeV. The normalization uncertainty of $\pm2.6\%$ is excluded.

Transverse momentum spectrum of $K^{+} + K^{-}$ measured at midrapidity ($|y|<0.5$) in inelastic pp collisions at $\sqrt{s}$ = 13 TeV. The normalization uncertainty of $\pm2.6\%$ is excluded.

Transverse momentum spectrum of $K^{0}_{S}$ measured at midrapidity ($|y|<0.5$) in inelastic pp collisions at $\sqrt{s}$ = 13 TeV. The normalization uncertainty of $\pm2.6\%$ is excluded.

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J/$\psi$ production as a function of charged-particle multiplicity in p-Pb collisions at $\sqrt{\textit{s}_{\rm NN}}~=~8.16$ TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
JHEP 09 (2020) 162, 2020.
Inspire Record 1792996 DOI 10.17182/hepdata.97018

Inclusive J/$\psi$ yields and average transverse momenta in p-Pb collisions at a center-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}}$ = 8.16 TeV are measured as a function of the charged-particle pseudorapidity density with ALICE. The J/$\psi$ mesons are reconstructed at forward $(2.03 < y_{\rm cms} < 3.53)$ and backward ($-4.46 < y_{\rm cms} < -2.96$) center-of-mass rapidity in their dimuon decay channel while the charged-particle pseudorapidity density is measured around midrapidity. The J/$\psi$ yields at forward and backward rapidity normalized to their respective average values increase with the normalized charged-particle pseudorapidity density, the former showing a weaker increase than the latter. The normalized average transverse momenta at forward and backward rapidity manifest a steady increase from low to high charged-particle pseudorapidity density with a saturation beyond the average value.

6 data tables

Relative yield of inclusive J/psi as a function of relative charged-particle pseudorapidity density at forward rapidity 2.03 < y_cms < 3.53 (p-going direction).

Relative yield of inclusive J/psi as a function of relative charged-particle pseudorapidity density at backward rapidity -4.46 < y_cms < -2.96 (Pb-going direction).

Mean transverse momentum of inclusive J/psi as a function of the relative charged-particle pseudorapidity density at forward rapidity 2.03 < y_cms < 3.53 (p-going direction).

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Measurement of nuclear effects on $\psi\rm{(2S)}$ production in p-Pb collisions at $\sqrt{\textit{s}_{\rm NN}} = 8.16$ TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
JHEP 07 (2020) 237, 2020.
Inspire Record 1785315 DOI 10.17182/hepdata.96029

Inclusive $\psi$(2S) production is measured in p-Pb collisions at the centre-of-mass energy per nucleon-nucleon pair $\sqrt{s_{\rm{NN}}}=8.16$ TeV, using the ALICE detector at the CERN LHC. The production of $\psi$(2S) is studied at forward ($2.03 < y_{\rm cms} < 3.53$) and backward ($-4.46 < y_{\rm cms} < -2.96$) centre-of-mass rapidity and for transverse momentum $p_{\rm{T}}$ $<$ 12 GeV/$c$ via the decay to muon pairs. In this paper, we report the integrated as well as the $y_{\rm cms}$- and $p_{\rm T}$-differential inclusive production cross sections. Nuclear effects on $\psi$(2S) production are studied via the determination of the nuclear modification factor that shows a strong suppression at both forward and backward centre-of-mass rapidities. Comparisons with corresponding results for inclusive J/$\psi$ show a similar suppression for the two states at forward rapidity (p-going direction), but a stronger suppression for $\psi$(2S) at backward rapidity (Pb-going direction). As a function of $p_{\rm T}$, no clear dependence of the nuclear modification factor is found. The relative size of nuclear effects on $\psi$(2S) production compared to J/$\psi$ is also studied via the double ratio of production cross sections $[\sigma_{\psi(2S)}/\sigma_{\rm{J/}\psi}]_{\rm pPb}/[\sigma_{\psi(2S)}/\sigma_{\rm{J/}\psi}]_{\rm pp}$ between p-Pb and pp collisions. The results are compared with theoretical models that include various effects related to the initial and final state of the collision system and also with previous measurements at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV.

14 data tables

Inclusive $\psi(2{\rm S})$ differential cross section times branching ratio as a function of $y_{\rm cms}$, in p--Pb collisions at $\sqrt{s_{\rm NN}}$ = 8.16 TeV. The first uncertainty is statistical, the second is the uncorrelated systematic, while the third one is a correlated systematic uncertainty.

Inclusive $\psi(2{\rm S})$ differential cross section times branching ratio as a function of $p_{\rm T}$, at forward rapidity at $\sqrt{s_{\rm NN}}$ = 8.16 TeV .The first uncertainty is statistical, the second is the uncorrelated systematic, while the third one is a correlated systematic uncertainty.

Inclusive $\psi(2{\rm S})$ differential cross section times branching ratio as a function of $p_{\rm T}$, at backward rapidity at $\sqrt{s_{\rm NN}}$ = 8.16 TeV .The first uncertainty is statistical, the second is the uncorrelated systematic, while the third one is a correlated systematic uncertainty.

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$\rm{K}^{*}(\rm{892})^{0}$ and $\phi(1020)$ production at midrapidity in pp collisions at $\sqrt{s}$ = 8 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adhya, Souvik Priyam ; et al.
Phys.Rev.C 102 (2020) 024912, 2020.
Inspire Record 1762364 DOI 10.17182/hepdata.99928

The production of $\mathrm{K}^{*}(\mathrm{892})^{0}$ and $\mathrm{\phi(1020)}$ in pp collisions at $\sqrt{s}$ = 8 TeV was measured using Run 1 data collected by the ALICE collaboration at the LHC. The $p_{\rm{T}}$-differential yields d$^{\rm 2}N$/d$y$d$p_{\rm{T}}$ in the range $0 < p_{\rm{T}} < 20$ GeV/$c$ for $\rm{K}^{*0}$ and $0.4 < p_{\rm{T}} < 16$ GeV/$c$ for $\phi$ have been measured at midrapidity, $|y| < 0.5$. Moreover, improved measurements of the $\rm{K}^{*}(892)^{0}$ and $\phi(1020)$ at $\sqrt{s} = 7$TeV are presented. The collision energy dependence of $p_{\rm{T}}$ distributions, $p_{\rm{T}}$-integrated yields and particle ratios in inelastic pp collisions are examined. The results are also compared with different collision systems. The values of the particle ratios are found to be similar to those measured at other LHC energies. In pp collisions a hardening of the particle spectra is observed with increasing energy, but at the same time it is also observed that the relative particle abundances are independent of the collision energy. The $p_{\rm{T}}$-differential yields of $\rm{K}^{*0}$ and $\phi$ in pp collisions at $\sqrt{s} = 8$ TeV are compared with the expectations of different Monte Carlo event generators.

13 data tables
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Inclusive $\Upsilon$ production in p-Pb collisions at $\sqrt{s_{\rm NN}}$ = 8.16 TeV

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adler, Alexander ; et al.
Phys.Lett.B 806 (2020) 135486, 2020.
Inspire Record 1762360 DOI 10.17182/hepdata.95539

$\Upsilon$ production in p-Pb interactions is studied at the centre-of-mass energy per nucleon-nucleon collision $\sqrt{s_{\rm{NN}}}$ = 8.16 TeV with the ALICE detector at the CERN LHC. The measurement is performed reconstructing bottomonium resonances via their dimuon decay channel, in the centre-of-mass rapidity intervals $2.03 < y_{\rm{cms}} < 3.53$ and $-4.46 < y_{\rm{cms}} < -2.96$, down to zero transverse momentum. In this work, results on the inclusive $\Upsilon(1\rm{S})$ production cross section as a function of rapidity and transverse momentum are presented. The corresponding nuclear modification factor shows a suppression of the $\Upsilon(1\rm{S})$ yields with respect to pp collisions, both at forward and backward rapidity. This suppression is stronger in the low transverse momentum region and shows no significant dependence on the centrality of the interactions. Furthermore, the $\Upsilon(2\rm{S})$ nuclear modification factor is also evaluated, suggesting a suppression similar to that of the $\Upsilon(1\rm{S})$. A first measurement of the $\Upsilon(3\rm{S})$ has also been performed. Finally, results are compared with previous measurements performed by ALICE in p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV and with theoretical calculations.

18 data tables

$\Upsilon$(1S) differential cross section as a function of $y_{\rm cms}$, in p--Pb collisions at $\sqrt{s_{\rm NN}}$ = 8.16 TeV. The first uncertainty is statistical, while the second is the systematic.

$\Upsilon$(2S) differential cross section times as a function of $y_{\rm cms}$, in p--Pb collisions at $\sqrt{s_{\rm NN}}$ = 8.16 TeV. The first uncertainty is statistical, while the second is the systematic.

$\Upsilon$(3S) differential cross section as a function of $y_{\rm cms}$, in p--Pb collisions at $\sqrt{s_{\rm NN}}$ = 8.16 TeV. The first uncertainty is statistical, while the second is the systematic.

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Search for production of $WW/WZ$ resonances decaying to a lepton, neutrino and jets in $pp$ collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J.C 75 (2015) 209, 2015.
Inspire Record 1352826 DOI 10.17182/hepdata.68389

A search is presented for narrow diboson resonances decaying to $WW$ or $WZ$ in the final state where one $W$ boson decays leptonically (to an electron or a muon plus a neutrino) and the other $W/Z$ boson decays hadronically. The analysis is performed using an integrated luminosity of 20.3 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}$ = 8 TeV collected by the ATLAS detector at the LHC. No evidence for resonant diboson production is observed, and resonance masses below 700 GeV and 1490 GeV are excluded at 95% confidence level for the spin-2 Randall-Sundrum bulk graviton $G^*$ with coupling constant of 1.0 and the extended gauge model $W'$ boson respectively.

5 data tables

Reconstructed mass distribution in the low-pt resolved region (LRR).

Reconstructed mass distribution in the high-pt resolved region (HRR).

Reconstructed mass distribution in the merged region (MR).

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Evidence of $W\gamma\gamma$ production in $pp$ collisions at $\sqrt{s}=8$ TeV and limits on anomalous quartic gauge couplings with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.Lett. 115 (2015) 031802, 2015.
Inspire Record 1351760 DOI 10.17182/hepdata.45260

This Letter reports evidence of triple gauge boson production $pp\to W(\ell\nu)\gamma\gamma + X$, which is accessible for the first time with the 8 TeV LHC data set. The fiducial cross section for this process is measured in a data sample corresponding to an integrated luminosity of 20.3 fb$^{-1}$, collected by the ATLAS detector in 2012. Events are selected using the $W$ boson decay to $e\nu$ or $\mu\nu$ as well as requiring two isolated photons. The measured cross section is used to set limits on anomalous quartic gauge couplings in the high diphoton mass region.

3 data tables

The measured inclusive ($N_{jet}\geq$ 0) fiducial cross section in the e$\nu\gamma\gamma$, $\mu\nu\gamma\gamma$ channels together with the combined $\ell\nu\gamma\gamma$ cross section. The first uncertainty shown is the statistical uncertainty on the measurement, the second one is the total systematic uncertainty (excluding the term coming from the luminosity), the third one is the systematic uncertainty coming from the luminosity. A parton to particle correction factors of 0.99 is applied to the MCFM prediction.

The measured exclusive ($N_{jet}$ = 0) fiducial cross section in the e$\nu\gamma\gamma$, $\mu\nu\gamma\gamma$ channels together with the combined $\ell\nu\gamma\gamma$ cross section. The first uncertainty shown is the statistical uncertainty on the measurement, the second one is the total systematic uncertainty (excluding the term coming from the luminosity), the third one is the systematic uncertainty coming from the luminosity. A parton to particle correction factor of 0.87 is applied to the MCFM prediction.

Observed and expected 95\% CL limits obtained for the $f_{\mathrm{T0}}/\Lambda^4$, $f_{\mathrm{M2}}/\Lambda^4$ and $f_{\mathrm{M3}}/\Lambda^4$ aQGC parameters for the combination of the two channels. The values of $n = 0,\,1,\,2$ are the exponential choices of the form factor, $\Lambda_{\rm{FF}}$ is fixed to $600$ GeV for $f_{\mathrm{T0}}/\Lambda^4$ and to $500$ GeV for the other parameters. The $n=0$ choice produces the limits without the form factor applied.


A search for high-mass resonances decaying to $\tau^{+}\tau^{-}$ in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 07 (2015) 157, 2015.
Inspire Record 1346398 DOI 10.17182/hepdata.68362

A search for high-mass resonances decaying into $\tau^{+}\tau^{-}$ final states using proton-proton collisions at $\sqrt{s}= 8$ TeV produced by the Large Hadron Collider is presented. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 19.5-20.3 fb$^{-1}$. No statistically significant excess above the Standard Model expectation is observed; 95% credibility upper limits are set on the cross section times branching fraction of $Z^{\prime}$ resonances decaying into $\tau^+\tau^-$ pairs as a function of the resonance mass. As a result, $Z^{\prime}$ bosons of the Sequential Standard Model with masses less than 2.02 TeV are excluded at 95% credibility. The impact of the fermionic couplings on the $Z^{\prime}$ acceptance is investigated and limits are also placed on a $Z^{\prime}$ model that exhibits enhanced couplings to third-generation fermions.

9 data tables

Signal acceptance times efficiency (ACC*EFF) for Z'L, Z'R, Z'narrow and Z'wide divided by ACC*EFF for Z'SSM as a function of the Z' mass, separately for the had-had and lep-had channels.

Ratio of the Z'NU to Z'SSM cross section times tau+tau- branching fraction (SIG*BR) as a function of sin^2phi and the Z' mass.

Ratio of the Z'NU to Z'SSM acceptance times efficiency (ACC*EFF) in the had-had channel as a function of sin^2phi and the Z' mass.

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