Multi-strange baryon production in $pp$ collisions at $\sqrt{s} = 7$ TeV with ALICE

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Lett. B712 (2012) 309-318, 2012.
Inspire Record 1097057 DOI 10.17182/hepdata.60477

A measurement of the multi-strange Xi- and Omega- baryons and their antiparticles by the ALICE experiment at the CERN Large Hadron Collider (LHC) is presented for inelastic proton-proton collisions at centre of mass energy of 7 TeV. The transverse momentum (pt) distributions were studied at mid-rapidity (|y| < 0.5) in the range of 0.6 < pt < 8.5 GeV/c for Xi- and Xi+ baryons, and in the range of 0.8 < pt < 5 GeV/c for Omega- and Omega+. Baryons and antibaryons were measured as separate particles and we find that the baryon to antibaryon ratio of both particle species is consistent with unity over the entire range of the measurement. The statistical precision of the current LHC data has allowed us to measure a difference between the mean pt of Xi- (Xi+) and Omega- (Omega+). Particle yields, mean pt, and the spectra in the intermediate pt range are not well described by the PYTHIA Perugia 2011 tune Monte Carlo event generator, which has been tuned to reproduce the early LHC data. The discrepancy is largest for Omega- (Omega+). This PYTHIA tune approaches the pt spectra of Xi- and Xi+ baryons below pt < 0.85 GeV/c and describes the Xi- and Xi+ spectra above pt > 6.0 GeV/c. We also illustrate the difference between the experimental data and model by comparing the corresponding ratios of (Omega-+Omega+)/(Xi-+Xi+) as a function of transverse mass.

3 data tables

pT differential yield for OMEGA- and OMEGABAR+ production in P-P collisions in the rapidity range -5 to 0.5. Note: there is no division by (2.pi.pT) included in the ordinate values.

pT differential yield for XI- and XIBAR+ production in P-P collisions in the rapidity range -5 to 0.5. Note: there is no division by (2.pi.pT) included in the ordinate values.

Ratio of (OMEGA-+OMEGABAR+) to (XI-+XIBAR+) production as a function of MT-M0. Note: the binning in (mT-m0) is the consequence of the pT binning of the Omega spectra.


Suppression of high transverse momentum D mesons in central Pb-Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
JHEP 1209 (2012) 112, 2012.
Inspire Record 1093488 DOI 10.17182/hepdata.60103
19 data tables

The transverse momentum distribution for prompt D0 mesons in the Centrality range 0-20%. The second (sys) error is the systematic uncertainty from the B feed-down contribution. The first (sys) error is the systematic uncertainty from the other sources.

The transverse momentum distribution for prompt D0 mesons in the Centrality range 40-80%. The second (sys) error is the systematic uncertainty from the B feed-down contribution. The first (sys) error is the systematic uncertainty from the other sources.

The transverse momentum distribution for prompt D+ mesons in the Centrality range 0-20%. The second (sys) error is the systematic uncertainty from the B feed-down contribution. The first (sys) error is the systematic uncertainty from the other sources.

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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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Measurement of the Cross Section for Electromagnetic Dissociation with Neutron Emission in Pb-Pb Collisions at $\sqrt{s_{NN}}$ = 2.76 TeV

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Rev.Lett. 109 (2012) 252302, 2012.
Inspire Record 1093519 DOI 10.17182/hepdata.62076
4 data tables

Single EMD -> at least one neutron is emitted by a given Pb nucleus disregarding the fate of the other nucleus.

Mutual EMD -> at least one neutron is emitted by both Pb nuclei.

Measurement of the total hadronic Pb-Pb cross section at 2.76 TeV per nucleon.

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$J/\psi$ suppression at forward rapidity in Pb-Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Rev.Lett. 109 (2012) 072301, 2012.
Inspire Record 1088222 DOI 10.17182/hepdata.60297

The ALICE experiment has measured the inclusive J/psi production in Pb-Pb collisions at sqrt(sNN) = 2.76 TeV down to zero transverse momentum in the rapidity range 2.5 < y < 4. A suppression of the inclusive J/psi yield in Pb-Pb is observed with respect to the one measured in pp collisions scaled by the number of binary nucleon-nucleon collisions. The nuclear modification factor, integrated over the 0%-80% most central collisions, is 0.545+/-0.032(stat)+/-0.083(syst) and does not exhibit a significant dependence on the collision centrality. These features appear significantly different from measurements at lower collision energies. Models including J/psi production from charm quarks in a deconfined partonic phase can describe our data.

2 data tables

Jpsi Nuclear Modification Factor (Raa) measured in Pb-Pb collisions at sqrt(sNN) = 2.76 TeV in 2.5 < y < 4 and pt > 0 GeV/c, as a function of - the average number of participating nucleons (<Npart>), - the average number of participating nucleons (<Npart,w>) weigthed by the average number of binary collisions, - the mid-rapidity charged-particle density measured at pseudo-rapidity eta = 0 dNch,w/deta|eta=0 weigthed by the average number of binary collisions.

Centrality integrated (0%-80%) inclusive Jpsi Nuclear Modification Factor (Raa) measured in Pb-Pb collisions at sqrt(sNN) = 2.76 TeV as a function of rapidity for two transverse momentum ranges.


$J/\psi$ Production as a Function of Charged Particle Multiplicity in $pp$ Collisions at $\sqrt{s} = 7$ TeV

The ALICE collaboration Abelev, B. ; Adam, J. ; Adamova, D. ; et al.
Phys.Lett. B712 (2012) 165-175, 2012.
Inspire Record 1088833 DOI 10.17182/hepdata.38163
2 data tables

The relative J/psi yield (dN_(j/psi)/dy)/<dN_(j/psi)/dy> in the di-electron channel as a function of the relative charged particle multiplicity density (dN_(ch)/deta)/<dN_(ch)/deta>.

The relative J/psi yield (dN_(j/psi)/dy)/<dN_(j/psi)/dy> in the di-muon channel as a function of the relative charged particle multiplicity density (dN_(ch)/deta)/<dN_(ch)/deta>.


Measurement of charm production at central rapidity in proton-proton collisions at $\sqrt{s} = 7$ TeV

The ALICE collaboration Abelev, B. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
JHEP 1201 (2012) 128, 2012.
Inspire Record 944757 DOI 10.17182/hepdata.58524
4 data tables

Differential cross section for prompt D0 production.

Differential cross section for prompt D+ production.

Differential cross section for prompt D*+ production.

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Heavy flavour decay muon production at forward rapidity in proton–proton collisions at $\sqrt{s} =$ 7 TeV

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Lett. B708 (2012) 265-275, 2012.
Inspire Record 1084981 DOI 10.17182/hepdata.58676

The production of muons from heavy flavour decays is measured at forward rapidity in proton--proton collisions at \sqrt(s) = 7 TeV collected with the ALICE experiment at the LHC. The analysis is carried out on a data sample corresponding to an integrated luminosity L_{int} = 16.5 nb^{-1}. The transverse momentum and rapidity differential production cross sections of muons from heavy flavour decays are measured in the rapidity range 2.5 < y < 4, over the transverse momentum range 2 < p_{t} < 12 GeV/c. The results are compared to predictions based on perturbative QCD calculations.

7 data tables

pT-differential production cross section of muons from heavy flavour decays, in the rapidity range 2.5<y<4.

y-differential production cross section of muons from heavy flavour decays, in the range 2<pT<12 GeV/C.

pT-differential production cross section of muons from heavy flavour decays, in the rapidity range 2.5<y<2.8.

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Measurement of Event Background Fluctuations for Charged Particle Jet Reconstruction in Pb-Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
JHEP 1203 (2012) 053, 2012.
Inspire Record 1084331 DOI 10.17182/hepdata.58285
7 data tables

DeltaPT of random cones in the 10% most central events for three types of random cone probes with a minimum track PT of 0.15 GeV. (1) sampling all the events, (2) avoiding overlap with the leading jet candidate in the event and (3) after randomizing the (ETA,PHI) direction of the tracks hence destroying any correlations.

DeltaPT of random cones in the 10% most central events for three regions with a minimum track PT of 0.15 GeV. (1) the in-plane orientation where the angle between the reconstructed event plane and the random cone axis is < 30 degrees, (2) the out-of plane orientation where this angle is > 60 degrees and (3) the intermediate region where this angle is between 30 and 60 degrees.

Dependence of the standard deviation on the uncorrected charged particle multiplicity. As in figure 2 the data are given for three different random cone probes: (1) sampling all the events, (2) avoiding overlap with the leading jet candidate in the event and (3) after randomizing the (ETA,PHI) direction of the tracks hence destroying any correlations.

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Underlying Event measurements in $pp$ collisions at $\sqrt{s}=0.9$ and 7 TeV with the ALICE experiment at the LHC

The ALICE collaboration Abelev, Betty ; Abrahantes Quintana, Arian ; Adamova, Dagmar ; et al.
JHEP 1207 (2012) 116, 2012.
Inspire Record 1080735 DOI 10.17182/hepdata.58863

We present measurements of Underlying Event observables in pp collisions at sqrt(s) = 0.9 and 7 TeV. The analysis is performed as a function of the highest charged-particle transverse momentum pT,LT in the event. Different regions are defined with respect to the azimuthal direction of the leading (highest transverse momentum) track: Toward, Transverse and Away. The Toward and Away regions collect the fragmentation products of the hardest partonic interaction. The Transverse region is expected to be most sensitive to the Underlying Event activity. The study is performed with charged particles above three different pT thresholds: 0.15, 0.5 and 1.0 GeV/c. In the Transverse region we observe an increase in the multiplicity of a factor 2-3 between the lower and higher collision energies, depending on the track pT threshold considered. Data are compared to Pythia 6.4, Pythia 8.1 and Phojet. On average, all models considered underestimate the multiplicity and summed pT in the Transverse region by about 10-30%.

23 data tables

Number density as a function of the leading charged-particle PT at a centre-mass-energy of 900 GeV for events having charged-particle PT > 0.15 GeV. The data is shown for the three azimuthal regions.

Number density as a function of the leading charged-particle PT at a centre-mass-energy of 7000 GeV for events having charged-particle PT > 0.15 GeV. The data is shown for the three azimuthal regions.

Number density as a function of the leading charged-particle PT at a centre-mass-energy of 900 GeV for events having charged-particle PT > 0.5 GeV. The data is shown for the three azimuthal regions.

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Light vector meson production in $pp$ collisions at $\sqrt{s}=7$ TeV

The ALICE collaboration Abelev, B. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Phys.Lett. B710 (2012) 557-568, 2012.
Inspire Record 1080945 DOI 10.17182/hepdata.58629

The ALICE experiment has measured low-mass dimuon production in pp collisions at $\sqrt{s}$ = 7 TeV in the dimuon rapidity region 2.5 < y < 4. The observed dimuon mass spectrum is described as a superposition of resonance decays ($\eta, \rho, \omega, \eta^{'}, \phi$) into muons and semi-leptonic decays of charmed mesons. The measured production cross sections for $\omega$ and $\phi$ are $\sigma_\omega (1 < p_t < 5$ GeV/c,2.5 < y < 4) = 5.28 $\pm$ 0.54 (stat) $\pm$ 0.50 (syst) mb and $\sigma_\phi$(1 < $p_t$ < 5 GeV/c,2.5 < y < 4)=0.940 $\pm$ 0.084 (stat) $\pm$ 0.078 (syst) mb. The differential cross sections $d^2\sigma/dy dp_t$ are extracted as a function of $p_t$ for $\omega$ and $\phi$. The ratio between the $\rho$ and $\omega$ cross section is obtained. Results for the $\phi$ are compared with other measurements at the same energy and with predictions by models.

5 data tables

Differential phi cross section from the di-muon channel as a function of transverse momentum, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one.

Differential omega cross section from the di-muon channel as a function of transverse momentum, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one.

Total phi cross section from the di-muon data. The first error is statistical, the second is a systematic error.

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$J/\psi$ polarization in $pp$ collisions at $\sqrt{s}=7$ TeV

The ALICE collaboration Abelev, Betty ; Abrahantes Quintana, Arian ; Adamova, Dagmar ; et al.
Phys.Rev.Lett. 108 (2012) 082001, 2012.
Inspire Record 944730 DOI 10.17182/hepdata.73005

The ALICE Collaboration has studied J/psi production in pp collisions at $\sqrt{s}$=7 TeV at the LHC through its muon pair decay. The polar and azimuthal angle distributions of the decay muons were measured, and results on the J/$\psi$ polarization parameters lambda_theta and lambda_phi were obtained. The study was performed in the kinematic region 2.5 < y < 4, 2 < $p_t$ < 8 GeV/c, in the helicity and Collins-Soper reference frames. The results for lambda_theta in the helicity frame show a longitudinal polarization at low $p_t$, vanishing with increasing transverse momentum. All the other polarization parameters are consistent with zero, within uncertainties.

4 data tables

$\lambda_\theta$ as a function of $p_{\rm T}$ for inclusive J/$\psi$, measured in the helicity reference frame.

$\lambda_\phi$ as a function of $p_{\rm T}$ for inclusive J/$\psi$, measured in the helicity reference frame.

$\lambda_\theta$ as a function of $p_{\rm T}$ for inclusive J/$\psi$, measured in the Collins-Soper reference frame.

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Particle-yield modification in jet-like azimuthal di-hadron correlations in Pb-Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV

The ALICE collaboration Aamodt, K. ; Abelev, B. ; Abrahantes Quintana, A. ; et al.
Phys.Rev.Lett. 108 (2012) 092301, 2012.
Inspire Record 930312 DOI 10.17182/hepdata.58113

The yield of charged particles associated with high-pT trigger particles (8 < pT < 15 GeV/c) is measured with the ALICE detector in Pb-Pb collisions at sqrt(s_NN) = 2.76 TeV relative to proton-proton collisions at the same energy. The conditional per-trigger yields are extracted from the narrow jet-like correlation peaks in azimuthal di-hadron correlations. In the 5% most central collisions, we observe that the yield of associated charged particles with transverse momenta pT > 3 GeV/c on the away-side drops to about 60% of that observed in pp collisions, while on the near-side a moderate enhancement of 20-30% is found.

6 data tables

The ratio of near-side yields in Lead-Lead/Proton-Proton collisions in the central region.

The ratio of near-side yields in Lead-Lead/Proton-Proton collisions in the peripheral region.

The ratio of away-side yields in Lead-Lead/Proton-Proton collisions in the central region.

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Harmonic decomposition of two-particle angular correlations in Pb-Pb collisions at $\sqrt{s_{NN}}=$ 2.76 TeV

The ALICE collaboration Aamodt, K. ; Abelev, B. ; Abrahantes Quintana, A. ; et al.
Phys.Lett. B708 (2012) 249-264, 2012.
Inspire Record 927105 DOI 10.17182/hepdata.58523
100 data tables

Amplitudes of the VnDelta harmonics versus n for events with trigger particles having transverse momenta in the range 2-2.5 GeV and associated particles in the range 1.5-2.0 GeV for two centrality classes 0-2% and 2-10%. Note that in the paper the data are plotted multiplied by 100.

Amplitudes of the VnDelta harmonics versus n for events with trigger particles having transverse momenta in the range 2-2.5 GeV and associated particles in the range 1.5-2.0 GeV for three centrality classes 10-20%, 20-30% and 40-50%. Note that in the paper the data are plotted multiplied by 100.

Amplitudes of the VnDelta harmonics versus n for events with trigger particles having transverse momenta in the range 8-15 GeV and associated particles in the range 6-8 GeV for two centrality classes 40-50% and 0-20%. Note that in the paper the data are plotted multiplied by 100.

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Rapidity and transverse momentum dependence of inclusive J$/\psi$ production in $pp$ collisions at $\sqrt{s} = 7$ TeV

The ALICE collaboration Aamodt, K. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Phys.Lett. B704 (2011) 442-455, 2011.
Inspire Record 897764 DOI 10.17182/hepdata.57452
5 data tables

Double differential J/PSI cross section from the di-electron channel as a function of transverse momentum, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one. The last four columns are the errors considering. a +1 polarization in the Collins-Soper frame, a -1 polarization in the Collins-Soper frame, a +1 polarization in the Helicity frame and a -1 polarization in the Helicity frame, respectively.

Differential J/PSI cross section from the di-muon channel as a function of transverse momentum, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one. The last four columns are the errors (in MUB/GEV) considering a +1 polarization in the Collins-Soper frame, a -1 polarization in the Collins-Soper frame, a +1 polarization in the Helicity frame and a -1 polarization in the Helicity frame, respectively.

Differential J/PSI cross section from the di-electron and di-muon channel as a function of rapidity, the first error is statistical, the first systematic error is the correlated one, the second is the non-correlated one. The last four columns are the errors (in MUB/GEV) considering. Data in the first point of this table updated from the erratum.

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Higher harmonic anisotropic flow measurements of charged particles in Pb-Pb collisions at $\sqrt{s_{NN}}$=2.76 TeV

The ALICE collaboration Aamodt, K. ; Abelev, B. ; Abrahantes Quintana, A. ; et al.
Phys.Rev.Lett. 107 (2011) 032301, 2011.
Inspire Record 900651 DOI 10.17182/hepdata.62026

We report on the first measurement of the triangular v3, quadrangular v4, and pentagonal v5 charged particle flow in Pb-Pb collisions at 2.76 TeV measured with the ALICE detector at the CERN Large Hadron Collider. We show that the triangular flow can be described in terms of the initial spatial anisotropy and its fluctuations, which provides strong constraints on its origin. In the most central events, where the elliptic flow v2 and v3 have similar magnitude, a double peaked structure in the two-particle azimuthal correlations is observed, which is often interpreted as a Mach cone response to fast partons. We show that this structure can be naturally explained from the measured anisotropic flow Fourier coefficients.

36 data tables

v2{SP} (red filled circles).

v3{SP} (blue filled squares).

v4{SP} (purprle stars).

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Two-pion Bose-Einstein correlations in central Pb-Pb collisions at $\sqrt{{s}_{NN}} =$ 2.76 TeV

The ALICE collaboration Aamodt, K. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Phys.Lett. B696 (2011) 328-337, 2011.
Inspire Record 881884 DOI 10.17182/hepdata.56743

The first measurement of two-pion Bose--Einstein correlations in central PbPb collisions at $\sqrt{s_{NN}} = 2.76$ TeV at the Large Hadron Collider is presented. We observe a growing trend with energy now not only for the longitudinal and the outward but also for the sideward pion source radius. The pion homogeneity volume and the decoupling time are significantly larger than those measured at RHIC.

14 data tables

Projections of the correlation function C.

Projections of the correlation function C.

Projections of the correlation function C.

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Femtoscopy of $pp$ collisions at $\sqrt{s}=0.9$ and 7 TeV at the LHC with two-pion Bose-Einstein correlations

The ALICE collaboration Aamodt, K. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Phys.Rev. D84 (2011) 112004, 2011.
Inspire Record 884741 DOI 10.17182/hepdata.74220

We report on the high statistics two-pion correlation functions from pp collisions at sqrt{s}=0.9 TeV and sqrt{s}=7 TeV, measured by the ALICE experiment at the Large Hadron Collider. The correlation functions as well as the extracted source radii scale with event multiplicity and pair momentum. When analyzed in the same multiplicity and pair transverse momentum range, the correlation is similar at the two collision energies. A three-dimensional femtoscopic analysis shows an increase of the emission zone with increasing event multiplicity as well as decreasing homogeneity lengths with increasing transverse momentum. The latter trend gets more pronounced as multiplicity increases. This suggests the development of space-momentum correlations, at least for collisions producing a high multiplicity of particles. We consider these trends in the context of previous femtoscopic studies in high-energy hadron and heavy-ion collisions, and discuss possible underlying physics mechanisms. Detailed analysis of the correlation reveals an exponential shape in the outward and longitudinal directions, while the sideward remains a Gaussian. This is interpreted as a result of a significant contribution of strongly decaying resonances to the emission region shape. Significant non-femtoscopic correlations are observed, and are argued to be the consequence of "mini-jet"-like structures extending to low p_T. They are well reproduced by the Monte-Carlo generators and seen also in pi^+ pi^- correlations.

14 data tables

Parameters of the three-dimensional Gaussian fits to the complete set of the correlation functions in 8 ranges in multiplicity and 6 in $k_{\rm T}$ for pp collisions at $\sqrt{s}$=7 TeV and 4 ranges in multiplicity and 6 in kT for pp collisions at $\sqrt{s}$=0.9 TeV.

Parameters of the three-dimensional Gaussian fits to the complete set of the correlation functions in 8 ranges in multiplicity and 6 in $k_{\rm T}$ for pp collisions at $\sqrt{s}$=7 TeV and 4 ranges in multiplicity and 6 in kT for pp collisions at $\sqrt{s}$=0.9 TeV.

Parameters of the three-dimensional Gaussian fits to the complete set of the correlation functions in 8 ranges in multiplicity and 6 in $k_{\rm T}$ for pp collisions at $\sqrt{s}$=7 TeV and 4 ranges in multiplicity and 6 in kT for pp collisions at $\sqrt{s}$=0.9 TeV.

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Production of pions, kaons and protons in $pp$ collisions at $\sqrt{s}= 900$ GeV with ALICE at the LHC

The ALICE collaboration Aamodt, K. ; Abel, N. ; Abeysekara, U. ; et al.
Eur.Phys.J. C71 (2011) 1655, 2011.
Inspire Record 885104 DOI 10.17182/hepdata.57568
4 data tables

Transverse momentum spectra for positive and negative pions.

Transverse momentum spectra for positive and negative kaons.

Transverse momentum spectra for protons and antiprotons.

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Strange particle production in proton-proton collisions at sqrt(s) = 0.9 TeV with ALICE at the LHC

The ALICE collaboration Aamodt, K. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Eur.Phys.J. C71 (2011) 1594, 2011.
Inspire Record 881474 DOI 10.17182/hepdata.57569

The production of mesons containing strange quarks (K0s, phi) and both singly and doubly strange baryons (Lambda, Anti-Lambda, and Xi+Anti-Xi) are measured at central rapidity in pp collisions at $\sqrt{s}$ = 0.9 TeV with the ALICE experiment at the LHC. The results are obtained from the analysis of about 250 k minimum bias events recorded in 2009. Measurements of yields (dN/dy) and transverse momentum spectra at central rapidities for inelastic pp collisions are presented. For mesons, we report yields (&lt;dN/dy>) of $0.184 \pm 0.002 stat. \pm 0.006 syst.$ for K0s and $0.021 \pm 0.004 stat. \pm 0.003 syst.$ for phi. For baryons, we find &lt;dN/dy> = 0.048 \pm 0.001 stat. \pm 0.004 syst.$ for $Lambda$, $0.047 \pm 0.002 stat. \pm 0.005 syst.$ for Anti-Lambda and $0.0101 \pm 0.0020 stat. \pm 0.0009 syst.$ for Xi+Anti-Xi. The results are also compared with predictions for identified particle spectra from QCD-inspired models and provide a baseline for comparisons with both future pp measurements at higher energies and heavy-ion collisions.

6 data tables

The measured production spectra for K0s hadrons as a function of pT.

The measured production spectra for Lambda hadrons as a function of pT.

The measured production spectra for Anti-Lambda hadrons as a function of pT.

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Centrality dependence of the charged-particle multiplicity density at mid-rapidity in Pb-Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV

The ALICE collaboration Aamodt, Kenneth ; Abrahantes Quintana, Arian ; Adamova, Dagmar ; et al.
Phys.Rev.Lett. 106 (2011) 032301, 2011.
Inspire Record 880049 DOI 10.17182/hepdata.57047
2 data tables

The charged particle multiplicity density measurements for the nine centrality classes. Also given are the mean values of NPART, the number of participating nucleon pairs calulcated fromthe Glauber model. The errors shown are the systematic errors, with the statistical errors being small.

The dependence of the charged particle multiplicity density on the number of participants in the collisions.


Suppression of Charged Particle Production at Large Transverse Momentum in Central Pb-Pb Collisions at $\sqrt{s_{NN}} =$ 2.76 TeV

The ALICE collaboration Aamodt, K. ; Abrahantes Quintana, A. ; Adamova, D. ; et al.
Phys.Lett. B696 (2011) 30-39, 2011.
Inspire Record 879583 DOI 10.17182/hepdata.63859
5 data tables

PT distributions of primary charged particles at mid-rapidity in central and peripheral PB-PB collisions.

PT distributions of primary charged particles at mid-rapidity in central and peripheral PB-PB collisions estimated from scaled PP data as described in the text of the paper.

Measurments of RAA, the nuclear modification factor (rate of PB-PB to P P cross section) in the central region.

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Elliptic flow of charged particles in Pb-Pb collisions at 2.76 TeV

The ALICE collaboration
Phys.Rev.Lett. 105 (2010) 252302, 2010.
Inspire Record 877822 DOI 10.17182/hepdata.62277

We report the first measurement of charged particle elliptic flow in Pb-Pb collisions at 2.76 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurement is performed in the central pseudorapidity region (|eta|<0.8) and transverse momentum range 0.2< p_t< 5.0 GeV/c. The elliptic flow signal v_2, measured using the 4-particle correlation method, averaged over transverse momentum and pseudorapidity is 0.087 +/- 0.002 (stat) +/- 0.004 (syst) in the 40-50% centrality class. The differential elliptic flow v_2(p_t) reaches a maximum of 0.2 near p_t = 3 GeV/c. Compared to RHIC Au-Au collisions at 200 GeV, the elliptic flow increases by about 30%. Some hydrodynamic model predictions which include viscous corrections are in agreement with the observed increase.

5 data tables

Transverse momentum dependence of v2 for centrality 40-50% from the 2- and 4-particle cumulant methods.

Transverse momentum dependence of v2{4} for centralities 10-20%, 20-30% and 30-40%.

Centrality dependence of elliptic flow, integrated over the pT range 0.2 < pT < 5.0 GeV, estimated with two- and multi-particle correlation techniques.

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Two-pion Bose-Einstein correlations in $pp$ collisions at $\sqrt{s}=900$ GeV

The ALICE collaboration Aamodt, K ; Abel, N ; Abeysekara, U ; et al.
Phys.Rev. D82 (2010) 052001, 2010.
Inspire Record 860477 DOI 10.17182/hepdata.55128

We report on the measurement of two-pion correlation functions from pp collisions at sqrt(s)=900 GeV performed by the ALICE experiment at the Large Hadron Collider. Our analysis shows an increase of the HBT radius with increasing event multiplicity, in line with other measurements done in particle- and nuclear collisions. Conversely, the strong decrease of the radius with increasing transverse momentum, as observed at RHIC and at Tevatron, is not manifest in our data.

36 data tables

Two-particle correlation functions for like-sign and unlike sign pion pairs.

Two-particle correlation functions for like-sign and unlike sign pion pairs.

Two-particle correlation functions for like-sign and unlike sign pion pairs.

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Transverse momentum spectra of charged particles in proton-proton collisions at $\sqrt{s} = 900$~GeV with ALICE at the LHC

The ALICE collaboration Aamodt, K ; Abel, N ; Abeysekara, U ; et al.
Phys.Lett. B693 (2010) 53-68, 2010.
Inspire Record 860416 DOI 10.17182/hepdata.56032
18 data tables

Average transverse momentum, including extrapolation to PT=0, for inelastic (INEL) events.

Average transverse momentum, including extrapolation to PT=0, for non-single diffractive (NSD) events.

Power law fit to spectrum for PT > 3 GeV.

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