Measurement of electrons from heavy-flavour hadron decays in p-Pb collisions at $\sqrt{s_{\rm NN}} =$ 5.02 TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
Phys.Lett. B754 (2016) 81-93, 2016.
Inspire Record 1394682 DOI 10.17182/hepdata.71455

The production of electrons from heavy-flavour hadron decays was measured as a function of transverse momentum ( pT ) in minimum-bias p–Pb collisions at sNN=5.02 TeV using the ALICE detector at the LHC. The measurement covers the pT interval 0.5<pT<12 GeV/c and the rapidity range −1.065<ycms<0.135 in the centre-of-mass reference frame. The contribution of electrons from background sources was subtracted using an invariant mass approach. The nuclear modification factor RpPb was calculated by comparing the pT -differential invariant cross section in p–Pb collisions to a pp reference at the same centre-of-mass energy, which was obtained by interpolating measurements at s=2.76 TeV and s=7 TeV . The RpPb is consistent with unity within uncertainties of about 25%, which become larger for pT below 1 GeV/c . The measurement shows that heavy-flavour production is consistent with binary scaling, so that a suppression in the high- pT yield in Pb–Pb collisions has to be attributed to effects induced by the hot medium produced in the final state. The data in p–Pb collisions are described by recent model calculations that include cold nuclear matter effects.

2 data tables

Double-differential cross section for the production of electrons, i.e. (electron + positron)/2, from heavy-flavour hadron decays as a function of transverse momentum for minimum-bias p--Pb collisions in the rapidity interval $-1.065 < y_{\rm cms} < 0.135$. The systematic uncertainties do not include an additional normalization uncertainty of 3.7%.

Nuclear modification factor $R_{\text{pPb}}$ of electrons from heavy-flavour hadron decays as a function of transverse momentum for minimum-bias p--Pb collisions in the rapidity interval $-1.065 < y_{\rm cms} < 0.135$.


Centrality dependence of inclusive J/ψ production in p-Pb collisions at $ \sqrt{s_{\mathrm{NN}}}=5.02 $ TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
JHEP 1511 (2015) 127, 2015.
Inspire Record 1380193 DOI 10.17182/hepdata.69212
11 data tables

Differential cross sections dsigma_JPsi/dydpt as function of pt at backward (-4.46<y_cms<-2.96) centre-of-mass rapidity. The first uncertainty is statistical, the second and third ones are the systematic uncertainties. The third uncertainty is fully correlated over pT.

Differential cross sections d^2sigma^cent_JPsi/dydpt as function of pt for six centrality classes at forward (2.03<y_cms<3.53) centre-of-mass rapidity. The first uncertainty is statistical, the second and third ones are the systematic uncertainties. The third uncertainty is fully correlated over pT.

Differential cross sections dsigma^cent_JPsi/dy for four centrality classes at mid-rapidity (-1.37<y_cms<0.43). The first uncertainty is statistical, the second and third ones are the systematic uncertainties. The third uncertainty is fully correlated over centrality.

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Measurement of charm and beauty production at central rapidity versus charged-particle multiplicity in proton-proton collisions at $ \sqrt{s}=7 $ TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
JHEP 1509 (2015) 148, 2015.
Inspire Record 1366028 DOI 10.17182/hepdata.69529

Prompt D meson and non-prompt J/ψ yields are studied as a function of the multiplicity of charged particles produced in inelastic proton-proton collisions at a centre-of-mass energy of $ \sqrt{s}=7 $ TeV. The results are reported as a ratio between yields in a given multiplicity interval normalised to the multiplicity-integrated ones (relative yields). They are shown as a function of the multiplicity of charged particles normalised to the average value for inelastic collisions (relative charged-particle multiplicity). D$^{0}$, D$^{+}$ and D$^{*+}$ mesons are measured in five p$_{T}$ intervals from 1 GeV/c to 20 GeV/c and for |y| < 0.5 via their hadronic decays. The D-meson relative yield is found to increase with increasing charged-particle multiplicity. For events with multiplicity six times higher than the average multiplicity of inelastic collisions, a yield enhancement of a factor about 15 relative to the multiplicity-integrated yield in inelastic collisions is observed. The yield enhancement is independent of transverse momentum within the uncertainties of the measurement. The D$^{0}$-meson relative yield is also measured as a function of the relative multiplicity at forward pseudo-rapidity. The non-prompt J/ψ, i.e. the B hadron, contribution to the inclusive J/ψ production is measured in the di-electron decay channel at central rapidity. It is evaluated for p$_{T}$ > 1.3 GeV/c and |y| < 0.9, and extrapolated to p$_{T}$ > 0. The fraction of non-prompt J/ψ in the inclusive J/ψ yields shows no dependence on the charged-particle multiplicity at central rapidity. Charm and beauty hadron relative yields exhibit a similar increase with increasing charged-particle multiplicity. The measurements are compared to PYTHIA 8, EPOS 3 and percolation calculations.

7 data tables

Average of D$^{0}$, D$^{+}$ and D*$^{+}$ mesons relative yields for the sum of particle and antiparticle in several multiplicity and PT intervals for PP collisions at $\sqrt{s}=7$ TeV as a function of the relative charged-particle multiplicity at central rapidity. The values are reported together with their uncertainties, which are quoted in the the order: statistical, systematic and feed-down contribution uncertainties. The yields reported here are per inelastic event.

Average of D$^{0}$, D$^{+}$ and D*$^{+}$ mesons relative yields for the sum of particle and antiparticle in several multiplicity and PT intervals for PP collisions at $\sqrt{s}=7$ TeV as a function of the relative charged-particle multiplicity at central rapidity. The values are reported together with their uncertainties, which are quoted in the the order: statistical, systematic and feed-down contribution uncertainties. The yields reported here are not corrected by the trigger selection efficiency, they are normalised to the visible cross section.

D$^{0}$-meson relative yields for the sum of particle and antiparticle in several multiplicity and PT intervals for pp collisions at $\sqrt{s}=7$ TeV as a function of the relative average multiplicity in the V0 detector, $N_{V0} \big/ \langle N_{V0} \rangle$. The yields reported here are normalised to the inelastic cross section.

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Inclusive, prompt and non-prompt J/$\psi$ production at mid-rapidity in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
JHEP 1507 (2015) 051, 2015.
Inspire Record 1364887 DOI 10.17182/hepdata.68881

The transverse momentum (p$_{T}$) dependence of the nuclear modification factor R$_{AA}$ and the centrality dependence of the average transverse momentum 〈p$_{T}$〉 for inclusive J/ψ have been measured with ALICE for Pb-Pb collisions at $ \sqrt{s_{\mathrm{NN}}}=2.76 $ TeV in the e+e$^{−}$ decay channel at mid-rapidity (|y| < 0.8). The 〈p$_{T}$〉 is significantly smaller than the one observed for pp collisions at the same centre-of-mass energy. Consistently, an increase of R$_{AA}$ is observed towards low p$_{T}$. These observations might be indicative of a sizable contribution of charm quark coalescence to the J/ψ production. Additionally, the fraction of non-prompt J/ψ from beauty hadron decays, f$_{B}$, has been determined in the region 1.5 < p$_{T}$ < 10 GeV/c in three centrality intervals. No significant centrality dependence of f$_{B}$ is observed. Finally, the R$_{AA}$ of non-prompt J/ψ is discussed and compared with model predictions. The nuclear modification in the region 4.5 < p$_{T}$ < 10 GeV/c is found to be stronger than predicted by most models.

9 data tables

The average transverse momentum $\langle p_{\rm T} \rangle$ of inclusive J/$\psi$ measured at mid-rapidity in centrality selected Pb-Pb collisions as a function of the number of participants.

The average transverse momentum squared $\langle p_{\rm T}^{2} \rangle$ of inclusive J/$\psi$ measured at mid-rapidity in centrality selected Pb-Pb collisions as a function of the number of participants.

The ratio $\langle p_{\rm T}^{2} \rangle_{\rm AA} / \langle p_{\rm T}^{2} \rangle_{\rm pp}$ of inclusive J/$\psi$ measured at mid-rapidity in centrality selected Pb-Pb collisions as a function of the number of participants.

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Rapidity and transverse-momentum dependence of the inclusive J/$\psi$ nuclear modification factor in p-Pb collisions at $ \sqrt{s_{N\ N}} =$ 5.02 TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
JHEP 1506 (2015) 055, 2015.
Inspire Record 1355544 DOI 10.17182/hepdata.70846

We have studied the transverse-momentum (p$_{T}$) dependence of the inclusive J/ψ production in p-Pb collisions at $ \sqrt{s_{\mathrm{NN}}} $ = 5.02 TeV, in three center-of-mass rapidity (y$_{cms}$) regions, down to zero p$_{T}$. Results in the forward and backward rapidity ranges (2.03 < y$_{cms}$ < 3.53 and −4.46 < y$_{cms}$ < −2.96) are obtained by studying the J/ψ decay to μ$^{+}$ μ$^{−}$ , while the mid-rapidity region (−1.37 < y$_{cms}$ < 0.43) is investigated by measuring the e$^{+}$e$^{−}$ decay channel. The p$_{T}$ dependence of the J/ψ production cross section and nuclear modification factor are presented for each of the rapidity intervals, as well as the J/ψ mean p$_{T}$ values. Forward and mid-rapidity results show a suppression of the J/ψ yield, with respect to pp collisions, which decreases with increasing p$_{T}$. At backward rapidity no significant J/ψ suppression is observed. Theoretical models including a combination of cold nuclear matter effects such as shadowing and partonic energy loss, are in fair agreement with the data, except at forward rapidity and low transverse momentum. The implications of the p-Pb results for the evaluation of cold nuclear matter effects on J/ψ production in Pb-Pb collisions are also discussed.

9 data tables

$p_{\rm T}$-differential inclusive cross section ${\rm d}^2\sigma^{J/\psi}/{\rm d}y{\rm d}p_{T}$ in the backward rapidity range (-4.46<$y_{\rm cms}$<-2.96). The first uncertainty is statistical, the second one is the $p_{\rm T}$-uncorrelated systematic uncertainty, while the third is the $p_{\rm T}$-correlated one.

$p_{\rm T}$-differential inclusive cross section ${\rm d}^2\sigma^{J/\psi}/{\rm d}y{\rm d}p_{T}$ in the mid-rapidity range (-1.37<$y_{\rm cms}$<0.43). The first uncertainty is statistical, the second one is the $p_{\rm T}$-uncorrelated systematic uncertainty, while the third is the $p_{\rm T}$-correlated one.

$p_{\rm T}$-differential inclusive cross section ${\rm d}^2\sigma^{J/\psi}/{\rm d}y{\rm d}p_{T}$ in the forward rapidity range (2.03<$y_{\rm cms}$<3.53). The first uncertainty is statistical, the second one is the $p_{\rm T}$-uncorrelated systematic uncertainty, while the third is the $p_{\rm T}$-correlated one.

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Beauty production in pp collisions at $\sqrt{s}$ = 2.76 TeV measured via semi-electronic decays

The ALICE collaboration Abelev, Betty Bezverkhny ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Lett. B738 (2014) 97-108, 2014.
Inspire Record 1296861 DOI 10.17182/hepdata.858

The ALICE Collaboration at the LHC reports measurement of the inclusive production cross section of electrons from semi-leptonic decays of beauty hadrons with rapidity |y|<0.8 and transverse momentum 1<pT<10 GeV/c , in pp collisions at s=2.76 TeV . Electrons not originating from semi-electronic decay of beauty hadrons are suppressed using the impact parameter of the corresponding tracks. The production cross section of beauty decay electrons is compared to the result obtained with an alternative method which uses the distribution of the azimuthal angle between heavy-flavour decay electrons and charged hadrons. Perturbative QCD predictions agree with the measured cross section within the experimental and theoretical uncertainties. The integrated visible cross section, σb→e=3.47±0.40(stat)−1.33+1.12(sys)±0.07(norm) μb , was extrapolated to full phase space using Fixed Order plus Next-to-Leading Log (FONLL) calculations to obtain the total bb¯ production cross section, σbb¯=130±15.1(stat)−49.8+42.1(sys)−3.1+3.4(extr)±2.5(norm)±4.4(BR) μb .

8 data tables

Azimuthal correlation distribution between heavy-flavour decay electrons and charged hadrons, scaled by the number of electrons in minimum bias triggered events in the electron transverse momentum range 1.5-2.5 GeV/$c$.

Azimuthal correlation distribution between heavy-flavour decay electrons and charged hadrons, scaled by the number of electrons in EMCal triggered events in the electron transverse momentum range 4.5-6 GeV/$c$.

Relative beauty contribution to the heavy-flavour electron yield obtained with the method based on the track impact parameter.

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Measurement of electrons from semileptonic heavy-flavor hadron decays in $pp$ collisions at $\sqrt{s} = 2.76$ TeV

The ALICE collaboration Abelev, Betty Bezverkhny ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Rev. D91 (2015) 012001, 2015.
Inspire Record 1296860 DOI 10.17182/hepdata.64030

<p>The <inline-formula><mml:math display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:mi mathvariant="normal">T</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math></inline-formula>-differential production cross section of electrons from semileptonic decays of heavy-flavor hadrons has been measured at midrapidity in proton-proton collisions at <inline-formula><mml:math display="inline"><mml:mrow><mml:msqrt><mml:mrow><mml:mi>s</mml:mi></mml:mrow></mml:msqrt><mml:mo>=</mml:mo><mml:mn>2.76</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:mrow></mml:math></inline-formula> in the transverse momentum range <inline-formula><mml:math display="inline"><mml:mrow><mml:mn>0.5</mml:mn><mml:mo>&lt;</mml:mo><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:mi mathvariant="normal">T</mml:mi></mml:mrow></mml:msub><mml:mo>&lt;</mml:mo><mml:mn>12</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>GeV</mml:mi><mml:mo>/</mml:mo><mml:mi>c</mml:mi></mml:mrow></mml:math></inline-formula> with the ALICE detector at the LHC. The analysis was performed using minimum bias events and events triggered by the electromagnetic calorimeter. Predictions from perturbative QCD calculations agree with the data within the theoretical and experimental uncertainties.</p>

1 data table

Double-differential cross section for the production of electrons, i.e. (electron + positron)/2, from heavy-flavour hadron decays as a function of transverse momentum at mid-rapidity. The systematic uncertainties do not include an additional normalization uncertainty of 1.9%.


Measurement of electrons from beauty hadron decays in $pp$ collisions at $\sqrt{s}=7$ TeV

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Lett. B721 (2013) 13-23, 2013.
Inspire Record 1126962 DOI 10.17182/hepdata.61625

The production cross section of electrons from semileptonic decays of beauty hadrons was measured at mid-rapidity (|y|<0.8) in the transverse momentum range 1<p_T<8 GeV/c with the ALICE experiment at the CERN LHC in pp collisions at a center of mass energy s=7 TeV using an integrated luminosity of 2.2 nb^-^1. Electrons from beauty hadron decays were selected based on the displacement of the decay vertex from the collision vertex. A perturbative QCD calculation agrees with the measurement within uncertainties. The data were extrapolated to the full phase space to determine the total cross section for the production of beauty quark-antiquark pairs.

1 data table

Double differential cross section for charm and beauty electron production as a function of transverse momentum. The systematic error does not include the error on the Luminosity (3.5%).


Measurement of electrons from semileptonic heavy-flavour hadron decays in pp collisions at \sqrt{s} = 7 TeV

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Rev. D86 (2012) 112007, 2012.
Inspire Record 1115824 DOI 10.17182/hepdata.59998
1 data table

Double differential cross section for heavy-flavour electron production as a function of transverse momentum. The systematic error does not include the error on the Luminosity (3.5%).


Inclusive $J/\psi$ production in $pp$ collisions at $\sqrt{s} = 2.76$ TeV

The ALICE collaboration Abelev, B. ; Adam, J. ; Adamova, D. ; et al.
Phys.Lett. B718 (2012) 295-306, 2012.
Inspire Record 1094079 DOI 10.17182/hepdata.62231

The ALICE Collaboration has measured inclusive J/psi production in pp collisions at a center of mass energy sqrt(s)=2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges |y|<0.9 and 2.5<y<4 and have been obtained by measuring the electron and muon pair decay channels, respectively. The integrated luminosities for the two channels are L^e_int=1.1 nb^-1 and L^mu_int=19.9 nb^-1, and the corresponding signal statistics are N_J/psi^e+e-=59 +/- 14 and N_J/psi^mu+mu-=1364 +/- 53. We present dsigma_J/psi/dy for the two rapidity regions under study and, for the forward-y range, d^2sigma_J/psi/dydp_t in the transverse momentum domain 0<p_t<8 GeV/c. The results are compared with previously published results at sqrt(s)=7 TeV and with theoretical calculations.

4 data tables

Double differential J/$\psi$ production cross section at $\sqrt{s}=2.76$ TeV. The first uncertainty is statistical, the second one is $p_{\rm T}$-coorelated, the third one is uncorrelated. Polarization-related uncertainties are not included.

The $\sqrt{s}$-dependence of $\langle p_{\rm T}\rangle$ for inclusive J/$\psi$ production (forward rapidity).

the $\sqrt{s}$-dependence of $\langle p_{\rm T}\rangle$ for inclusive J/$\psi$ production (forward rapidity).

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