Date

Energy dependence of forward-rapidity J/$\psi$ and $\psi(2S)$ production in pp collisions at the LHC

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
No Journal Information, 2017.
Inspire Record 1511865 DOI 10.17182/hepdata.77781

We present results on transverse momentum ($p_{\rm T}$) and rapidity ($y$) differential production cross sections, mean transverse momentum and mean transverse momentum square of inclusive J/$\psi$ and $\psi(2S)$ at forward rapidity ($2.5<y<4$) as well as $\psi(2S)$-to-J/$\psi$ cross section ratios. These quantities are measured in pp collisions at center of mass energies $\sqrt{s}=5.02$ and 13 TeV with the ALICE detector. Both charmonium states are reconstructed in the dimuon decay channel, using the muon spectrometer. A comprehensive comparison to inclusive charmonium cross sections measured at $\sqrt{s}=2.76$, 7 and 8 TeV is performed. A comparison to non-relativistic quantum chromodynamics and fixed-order next-to-leading logarithm calculations, which describe prompt and non-prompt charmonium production respectively, is also presented. A good description of the data is obtained over the full $p_{\rm T}$ range, provided that both contributions are summed. In particular, it is found that for $p_{\rm T}>15$ GeV/$c$ the non-prompt contribution reaches up to 50% of the total charmonium yield.

14 data tables

Differential production cross sections of $J/\psi$ as a function of $p_{\rm T}$.

Differential production cross sections of $J/\psi$ as a function of rapidity.

Differential production cross sections of $\psi(2S)$ as a function of $p_{\rm T}$.

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Search for heavy Majorana neutrinos in e$^{±}$e$^{±}$+ jets and e$^{±}$ $\mu^{±}$+ jets events in proton-proton collisions at $ \sqrt{s}=8 $ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1604 (2016) 169, 2016.
Inspire Record 1426525 DOI 10.17182/hepdata.77059

A search is performed for heavy Majorana neutrinos (N) decaying into a W boson and a lepton using the CMS detector at the Large Hadron Collider. A signature of two jets and either two same sign electrons or a same sign electron-muon pair is searched for using 19.7 inverse femtobarns of data collected during 2012 in proton-proton collisions at a centre-of-mass energy of 8 TeV. The data are found to be consistent with the expected standard model (SM) background and, in the context of a Type-1 seesaw mechanism, upper limits are set on the cross section times branching fraction for production of heavy Majorana neutrinos in the mass range between 40 and 500 GeV. The results are additionally interpreted as limits on the mixing between the heavy Majorana neutrinos and the SM neutrinos. In the mass range considered, the upper limits range between 0.00015 - 0.72 for |V[eN]|^2 and 6.6E-5 - 0.47 for |V[eN] V*[muN]|^2 / ( |V[eN]|^2 + |V[muN]|^2 ), where V[lN] is the mixing element describing the mixing of the heavy neutrino with the SM neutrino of flavour l. These limits are the most restrictive direct limits for heavy Majorana neutrino masses above 200 GeV.

10 data tables

Selection requirements for the low- and high-mass signal regions.

ee channel. Selection requirements on discriminating variables determined by the optimization for each Majorana neutrino mass point. The last column shows the overall signal acceptance. Different selection criteria are used for low- and high-mass search regions. The "-" indicates that no selection requirement is made.

e$\mu$ channel. Selection requirements on discriminating variables determined by the optimization for each Majorana neutrino mass point. The last column shows the overall signal acceptance. Different selection criteria are used for low- and high-mass search regions. The ''-'' indicates that no selection requirement is made.

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Charged-particle distributions at low transverse momentum in $\sqrt{s} = 13$  TeV pp interactions measured with the ATLAS detector at the LHC

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Eur.Phys.J. C76 (2016) 502, 2016.
Inspire Record 1467230 DOI 10.17182/hepdata.73907
10 data tables

The average charged-particle muliplicity per unit of rapidity for ETARAP=0 as a function of the centre-of-mass energy.

The extrapolated ($\tau > 30$ ps) average charged-particle muliplicity per unit of rapidity for ETARAP=0 as a function of the centre-of-mass energy.

Charged-particle multiplicities in proton-proton collisions at a centre-of mass energy of 13000 GeV as a function of pseudorapidity for events with the number of charged particles >=2 having transverse momentum >100 MeV and absolute(pseudorapidity) <2.5.

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D-meson production in p-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV and in pp collisions at $\sqrt{s}=7$ TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
No Journal Information, 2016.
Inspire Record 1465513 DOI 10.17182/hepdata.73941

The production cross sections of the prompt charmed mesons D$^0$, D$^+$, D$^{*+}$ and D$_s$ were measured at mid-rapidity in p-Pb collisions at a centre-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}}=5.02$ TeV with the ALICE detector at the LHC. D mesons were reconstructed from their decays D$^0\rightarrow{\rm K}^-\pi^+$, D$^+\rightarrow{\rm K}^-\pi^+\pi^+$, D$^{*+}\rightarrow D^0\pi^+$, D$_s^+\rightarrow\phi\pi^+\rightarrow{\rm K}^-{\rm K}^+\pi^+$, and their charge conjugates. The $p_{\rm T}$-differential production cross sections were measured at mid-rapidity in the interval $1<p_{\rm T}<24$ GeV/$c$ for D$^0$, D$^+$ and D$^{*+}$ mesons and in $2<p_{\rm T}<12$ GeV/$c$ for D$_s$ mesons, using an analysis method based on the selection of decay topologies displaced from the interaction vertex. The production cross sections of the D$^0$, D$^+$ and D$^{*+}$ mesons were also measured in three $p_{\rm T}$ intervals as a function of the rapidity $y_{\rm cms}$ in the centre-of-mass system in $-1.26<y_{\rm cms}<0.34$. In addition, the prompt D$^0$ cross section was measured in pp collisions at $\sqrt{s}=7$ TeV and p-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV down to $p_{\rm T}=0$ using an analysis technique that is based on the estimation and subtraction of the combinatorial background, without reconstruction of the D$^0$ decay vertex. The nuclear modification factor $R_{\rm pPb}(p_{\rm T})$, defined as the ratio of the $p_{\rm T}$-differential D-meson cross section in p-Pb collisions and that in pp collisions scaled by the mass number of the Pb nucleus, was calculated for the four D-meson species and found to be compatible with unity within experimental uncertainties. The results are compared to theoretical calculations that include cold-nuclear-matter effects and to transport model calculations incorporating the interactions of charm quarks with an expanding deconfined medium.

21 data tables

pT-differential cross section of inclusive Dzero mesons in pp collisions at sqrt{sNN}=7 TeV in the rapidity interval |y|<0.5. Branching ratio of D0->Kpi : 0.0388.

pT-differential cross section of prompt Dzero mesons in pp collisions at sqrt{sNN}=7 TeV in the rapidity interval |y|<0.5. Branching ratio of D0->Kpi : 0.0388. Data points for pt<2 GeV/c from analysis "without vertexing". Data points for pt>2 GeV/c from the analysis "with vertexing" taken from JHEP 1201 (2012) 128 (http://hepdata.cedar.ac.uk/view/ins944757) and corrected for the updated BR value.

First column: production cross sections per unit of rapidity for prompt D0 mesons, inclusive D0 mesons (no feed-down subtraction) and charm quarks at mid-rapidity in pp collisions at 7 TeV. For D0 mesons, the second (sys) error is from the luminosity uncertainty, the third (sys) error is from the branching-ratio uncertainties. For charm quarks, the second (sys) error is from the luminosity uncertainty, the third (sys) error is from the Fragmentation Function uncertainties, the fourth (sys) error is from the rapidity shapes of D0 mesons and single charm quarks. Second column: total production cross sections, extrapolated to the full phase space, for prompt D0 mesons and charm quarks. For D0 mesons, the second (sys) error is the from the extrapolation uncertainty, the third from the luminosity uncertainty and the fourth from the branching-ratio uncertainties. For charm quarks, the second (sys) error is from the extrapolation, the third is from the luminosity uncertainty and the fourth is from the Fragmentation Function uncertainties. Third column: value of <pT> of prompt D0 mesons. The first uncertainty is statistical, the second is the systematic uncertainty.

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FAST TARGET FRAGMENTS IN INTERACTIONS OF RELATIVISTIC NUCLEI WITH PHOTOEMULSION. (IN RUSSIAN)

Antonchik, V.A. ; Bakaev, V.A. ; Bogdanov, V.G. ; et al.
Yad.Fiz. 46 (1987) 1344-1352, 1987.
Inspire Record 256945 DOI 10.17182/hepdata.2434
38 data tables

No description provided.

No description provided.

No description provided.

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$\rm{J}/\psi$ production at low transverse momentum in p+p and d+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev. C93 (2016) 064904, 2016.
Inspire Record 1420183 DOI 10.17182/hepdata.73526

We report on the measurement of J/ψ production in the dielectron channel at midrapidity (|y|<1) in p+p and d+Au collisions at sNN=200GeV from the STAR experiment at the Relativistic Heavy Ion Collider. The transverse momentum pT spectra in p+p for pT<4GeV/c and d+Au collisions for pT<3GeV/c are presented. These measurements extend the STAR coverage for J/ψ production in p+p collisions to low pT. The 〈pT2〉 from the measured J/ψ invariant cross section in p+p and d+Au collisions are evaluated and compared to similar measurements at other collision energies. The nuclear modification factor for J/ψ is extracted as a function of pT and collision centrality in d+Au and compared to model calculations using the modified nuclear parton distribution function and a final-state J/ψ nuclear absorption cross section.

6 data tables

The mean square of $p_T$.

Nuclear absorption cross section.

The nuclear modicifation factor vs. $p_T$ for $J\psi$ with |y| < 1 in 0-100 percent central d+Au collisions.

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Precision Measurement of the Longitudinal Double-spin Asymmetry for Inclusive Jet Production in Polarized Proton Collisions at $\sqrt{s}=200$ GeV

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev.Lett. 115 (2015) 092002, 2015.
Inspire Record 1297229 DOI 10.17182/hepdata.73432

We report a new high-precision measurement of the mid-rapidity inclusive jet longitudinal double-spin asymmetry, $A_{LL}$, in polarized $pp$ collisions at center-of-mass energy $\sqrt{s}=200$ GeV. The STAR data place stringent constraints on polarized parton distribution functions extracted at next-to-leading order from global analyses of inclusive deep inelastic scattering (DIS), semi-inclusive DIS, and RHIC $pp$ data. The measured asymmetries provide evidence for positive gluon polarization in the Bjorken-$x$ region $x>0.05$.

7 data tables

Jet neutral energy fraction (NEF) comparing data with simulations, where both are calculated with pT subtraction. This plot shows 8.4 < $p_T$ < 9.9 GeV/c.

Jet neutral energy fraction (NEF) comparing data with simulations, where both are calculated with pT subtraction. This plot shows 26.8 < $p_T$ < 31.6 GeV/c.

Inclusive jet $A_{LL}$ vs. parton jet $p_T$ for |eta|<0.5.

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GENERAL FEATURES AND CLUSTER - LIKE PROPERTIES OF REACTION K+ p ---> K+ p 2 pi+ 2 pi- AT 32-GeV/c

Azhinenko, I.V. ; Belokopytov, Yu.A. ; Chliapnikov, P.V. ; et al.
Sov.J.Nucl.Phys. 34 (1981) 584, 1981.
Inspire Record 165495 DOI 10.17182/hepdata.10705
58 data tables

No description provided.

No description provided.

No description provided.

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Study of Neutral Strange Particle Production in $p p$ Interactions at 32-{GeV}/$c$ and Comparison With $\bar{p} p$ Data

Bogolyubsky, M.Yu. ; Bumazhnov, V.A. ; Kiryunin, A.E. ; et al.
Sov.J.Nucl.Phys. 50 (1989) 424, 1989.
Inspire Record 269294 DOI 10.17182/hepdata.10310
15 data tables

No description provided.

No description provided.

No description provided.

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Differential studies of inclusive J/ψ and ψ(2S) production at forward rapidity in Pb-Pb collisions at $ \sqrt{s_{\mathrm{NN}}}=2.76 $ TeV

The ALICE collaboration Adam, Jaroslav ; Adamova, Dagmar ; Aggarwal, Madan Mohan ; et al.
JHEP 1605 (2016) 179, 2016.
Inspire Record 1380192 DOI 10.17182/hepdata.73094

The production of J/ψ and ψ(2S) was studied with the ALICE detector in Pb-Pb collisions at the LHC. The measurement was performed at forward rapidity (2.5 < y < 4) down to zero transverse momentum (p$_{t}$ ) in the dimuon decay channel. Inclusive J/ψ yields were extracted in different centrality classes and the centrality dependence of the average p$_{t}$ is presented. The J/ψ suppression, quantified with the nuclear modification factor (R$_{AA}$), was measured as a function of centrality, transverse momentum and rapidity. Comparisons with similar measurements at lower collision energy and theoretical models indicate that the J/ψ production is the result of an interplay between color screening and recombination mechanisms in a deconfined partonic medium, or at its hadronization. Results on the ψ(2S) suppression are provided via the ratio of ψ(2S) over J/ψ measured in pp and Pb-Pb collisions.

16 data tables

Values of $\langle p_{\rm T}\rangle$ and $\langle p^2_{\rm T}\rangle$ of inclusive J/$\psi$ measured in $0<p_{\rm T}<8$ GeV/$c$ and $2.5<y<4$. Statistical and systematic uncertainties are also reported.

Inclusive J/$\psi$ yields in $p_{\rm T}$ intervals for the 0-20%, 20-40% and 40-90% most central Pb-Pb collisions. The rapidity range is $2.5<y<4$. Statistical and systematic uncertainties are also reported. A global systematic uncertainty of 4% affects all the values. A 2%, 1% and 2% systematic uncertainty, independent of $p_{\rm T}$, affects the centrality classes 0-20%, 20-40% and 40-90%, respectively.

Inclusive J/$\psi$ $R_{\rm AA}$ and Pb-Pb yields as a function of centrality, $p_{\rm T}<8$ GeV/$c$ and $2.5<y<4.0$. Statistical and systematic uncertainties are also reported. A global systematic uncertainty of 15% (12%) affects all the $R_{\rm AA}$ (yields) values.

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Investigation of the breakup of a target nucleus in nucleus-nucleus collisions at an incident momentum of 4.2 GeV/c per nucleon

Bondarenko, A.I. ; Bondarenko, R.A. ; Kladnitskaya, E.N. ;
Phys.Atom.Nucl. 60 (1997) 1833-1842, 1997.
Inspire Record 1392946 DOI 10.17182/hepdata.17124
6 data tables

No description provided.

No description provided.

No description provided.

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Study of the Reaction $\bar{p} p \to p X$ at 22.4-{GeV}/$c$

The Alma Ata-Dubna-Helsinki-Kosice-Moscow-Prague-Tbilisi collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Dashian, N.B. ; et al.
Sov.J.Nucl.Phys. 33 (1981) 64-66, 1981.
Inspire Record 154173 DOI 10.17182/hepdata.69635
49 data tables

No description provided.

No description provided.

No description provided.

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Longitudinal momentum distributions of π− mesons produced in 12.7 GeV/c K+p and 7 GeV/c π+p interactions

Stone, S.L. ; Cohen, D. ; Farber, M. ; et al.
Nucl.Phys. B32 (1971) 19-28, 1971.
Inspire Record 1385801 DOI 10.17182/hepdata.33219

The center of mass longitudinal momentum distributions of π− mesons produced in K+p interactions at 12.7 GeV/c and in π+p interactions at 7 GeV/c exhibit an asymmetry similar to that observed, for example, in single particle production in 25 GeV/c π−p interactions. This asymmetry is discussed in terms of quark structure of hadrons and other dynamical models.

4 data tables

No description provided.

No description provided.

Mean PL and PT of PI-.

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Inelastic Interaction of Protons and Nucleons at an Energy of 9 BeV

Visky, T. ; Gramenitskii, I.M. ; Korbel, Z. ; et al.
Sov.Phys.JETP 14 (1962) 763-767, 1962.
Inspire Record 1388049 DOI 10.17182/hepdata.17008

The multiplicity dependence of the angular and energy characteristics of secondary particles in proton-nucleon collisions at 9 Bevis studied. A comparison is made with results of calculations based on the single-meson scheme.

9 data tables

No description provided.

No description provided.

No description provided.

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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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Charged jet cross sections and properties in proton-proton collisions at $\sqrt{s}=7$ TeV

The ALICE collaboration Abelev, Betty Bezverkhny ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Rev. D91 (2015) 112012, 2015.
Inspire Record 1328629 DOI 10.17182/hepdata.68515

The differential charged jet cross sections, jet fragmentation distributions, and jet shapes are measured in minimum bias proton-proton collisions at center-of-mass energy s=7  TeV using the ALICE detector at the LHC. Jets are reconstructed from charged particle momenta in the midrapidity region using the sequential recombination kT and anti-kT as well as the SISCone jet finding algorithms with several resolution parameters in the range R=0.2–0.6. Differential jet production cross sections measured with the three jet finders are in agreement in the transverse momentum (pT) interval 20<pTjet,ch<100  GeV/c. They are also consistent with prior measurements carried out at the LHC by the ATLAS Collaboration. The jet charged particle multiplicity rises monotonically with increasing jet pT, in qualitative agreement with prior observations at lower energies. The transverse profiles of leading jets are investigated using radial momentum density distributions as well as distributions of the average radius containing 80% (⟨R80⟩) of the reconstructed jet pT. The fragmentation of leading jets with R=0.4 using scaled pT spectra of the jet constituents is studied. The measurements are compared to model calculations from event generators (PYTHIA, PHOJET, HERWIG). The measured radial density distributions and ⟨R80⟩ distributions are well described by the PYTHIA model (tune Perugia-2011). The fragmentation distributions are better described by HERWIG.

73 data tables

Measured charged jet differential cross sections for INEL proton-proton collisions at $\sqrt{s}$ = 7 TeV.

Measured charged jet differential cross sections for INEL proton-proton collisions at $\sqrt{s}$ = 7 TeV.

Measured charged jet differential cross sections for INEL proton-proton collisions at $\sqrt{s}$ = 7 TeV.

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Multiplicity Dependence of Pion, Kaon, Proton and Lambda Production in p-Pb Collisions at $\sqrt{s_{NN}}$ = 5.02 TeV

The ALICE collaboration Abelev, Betty Bezverkhny ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Lett. B728 (2014) 25-38, 2014.
Inspire Record 1244523 DOI 10.17182/hepdata.61786

In this Letter, comprehensive results on ${\rm\pi}^\pm$, K$^\pm$, K$^0_S$, p, $\rm\bar{p}$, $\rm \Lambda$ and $\rm \bar{\Lambda}$ production at mid-rapidity ($0 < y_{\rm cms} < 0.5$) in p-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV, measured by the ALICE detector at the LHC, are reported. The transverse momentum distributions exhibit a hardening as a function of event multiplicity, which is stronger for heavier particles. This behavior is similar to what has been observed in pp and Pb-Pb collisions at the LHC. The measured $p_{\rm T}$ distributions are compared to results at lower energy and with predictions based on QCD-inspired and hydrodynamic models.

22 data tables

pT-differential invariant yield of charged pions in pPb collisions with centre-of-mass energy/nucleon=5.02 TeV.

pT-differential invariant yield of charged pions in pPb collisions with centre-of-mass energy/nucleon=5.02 TeV.

pT-differential invariant yield of charged kaons in pPb collisions with centre-of-mass energy/nucleon=5.02 TeV.

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Multiplicity dependence of the average transverse momentum in pp, p-Pb, and Pb-Pb collisions at the LHC

The ALICE collaboration Abelev, Betty Bezverkhny ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Phys.Lett. B727 (2013) 371-380, 2013.
Inspire Record 1241423 DOI 10.17182/hepdata.61692
5 data tables

The average transverse momentum as a function of multiplicity of charged particles having transverse momentum in the range 0.15-10 GeV/c and |eta| < 0.3 produced from P-P collisions at a centre-of mass energy/nucleon of 0.9 TeV.

The average transverse momentum as a function of multiplicity of charged particles having transverse momentum in the range 0.15-10 GeV/c and |eta| < 0.3 produced from P-P collisions at a centre-of mass energy/nucleon of 2.76 TeV.

The average transverse momentum as a function of multiplicity of charged particles having transverse momentum in the range 0.15-10 GeV/c and |eta| < 0.3 produced from P-P collisions at a centre-of mass energy/nucleon of 7 TeV.

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Fragmentation characteristics of relativistic carbon nucleus at its interaction with hydrogen

Belaga, V.V. ; Bondarenko, A.I. ; Karshiev, D.A. ; et al.
Phys.Atom.Nucl. 59 (1996) 991-996, 1996.
Inspire Record 404821 DOI 10.17182/hepdata.38625
3 data tables

FRAGB - BEAM FRAGMENT WITH Z>=2.



Transverse sphericity of primary charged particles in minimum bias proton-proton collisions at $\sqrt{s}=0.9$, 2.76 and 7 TeV

The ALICE collaboration Abelev, Betty ; Adam, Jaroslav ; Adamova, Dagmar ; et al.
Eur.Phys.J. C72 (2012) 2124, 2012.
Inspire Record 1115186 DOI 10.17182/hepdata.58857

Measurements of the sphericity of primary charged particles in minimum bias proton--proton collisions at sqrt(s)=0.9, 2.76 and 7 TeV with the ALICE detector at the LHC are presented. The observable is linearized to be collinear safe and is measured in the plane perpendicular to the beam direction using primary charged tracks with $p_{\rm T}\geq0.5$ GeV/c in $|\eta|\leq0.8$. The mean sphericity as a function of the charged particle multiplicity at mid-rapidity ($N_{\rm ch}$) is reported for events with different $p_{\rm T}$ scales ("soft" and "hard") defined by the transverse momentum of the leading particle. In addition, the mean charged particle transverse momentum versus multiplicity is presented for the different event classes, and the sphericity distributions in bins of multiplicity are presented. The data are compared with calculations of standard Monte Carlo event generators. The transverse sphericity is found to grow with multiplicity at all collision energies, with a steeper rise at low $N_{\rm ch}$, whereas the event generators show the opposite tendency. The combined study of the sphericity and the mean $p_{\rm T}$ with multiplicity indicates that most of the tested event generators produce events with higher multiplicity by generating more back-to-back jets resulting in decreased sphericity (and isotropy). The PYTHIA6 generator with tune PERUGIA-2011 exhibits a noticeable improvement in describing the data, compared to the other tested generators.

7 data tables

pp @ 900 GeV, Mean Transverse Sphericity (y) vs Multiplicity.

pp @ 7000 GeV, Mean Transverse Sphericity (y) vs Multiplicity.

pp @ 2760 GeV, Mean Transverse Sphericity (y) vs Multiplicity.

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Transverse momentum distributions of J / psi, psi-prime, Drell-Yan and continuum dimuons produced in Pb Pb interactions at the SPS

The NA50 collaboration Abreu, M.C. ; Alessandro, B. ; Alexa, C. ; et al.
Phys.Lett. B499 (2001) 85-96, 2001.
Inspire Record 537484 DOI 10.17182/hepdata.57431
9 data tables

Mean values of PT and PT**2 calculated from the IMR distributions.

Mean values of PT and PT**2 calculated from the J/PSI distributions.

Mean values of PT and PT**2 calculated from the PSI(3685) distributions.

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Bottomonium and Drell-Yan production in p-A collisions at 450- GeV

The NA50 collaboration Alessandro, B. ; Alexa, C. ; Arnaldi, R. ; et al.
Phys.Lett. B635 (2006) 260-269, 2006.
Inspire Record 712992 DOI 10.17182/hepdata.57411

The NA50 Collaboration has measured heavy-quarkonium production in p-A collisions at 450 GeV incident energy (sqrt(s) = 29.1 GeV). We report here results on the production of the Upsilon states and of high-mass Drell-Yan muon pairs (m > 6 GeV). The cross-section at midrapidity and the A-dependence of the measured yields are determined and compared with the results of other fixed-target experiments and with the available theoretical estimates. Finally, we also address some issues concerning the transverse momentum distributions of the measured dimuons.

3 data tables

Drell-Yann (for the mass region MMUMU>6GeV/c**2) and bottomonium cross sections, and their ratio.

Mean pT and Mean PT**2 for Drell-Yann (4.5<MMUMU<8 GeV/c**2) Errors for Drell-Yann are purely statistical, error value for Upsilon includes a systematical error due to uncertianty in the extrapolation of the drell-yann yield into the upsilon region. The total error is anyway dominated by the statistical contribution.

ALPHA parameter.


$J/\psi$ production from proton proton collisions at $\sqrt{s}$ = 200-GeV

The PHENIX collaboration Adler, S.S. ; Afanasiev, S. ; Aidala, C. ; et al.
Phys.Rev.Lett. 92 (2004) 051802, 2004.
Inspire Record 623000 DOI 10.17182/hepdata.57093

J/psi production has been measured in proton-proton collisions at sqrt(s)= 200 GeV over a wide rapidity and transverse momentum range by the PHENIX experiment at RHIC. Distributions of the rapidity and transverse momentum, along with measurements of the mean transverse momentum and total production cross section are presented and compared to available theoretical calculations. The total J/psi cross section is 3.99 +/- 0.61(stat) +/- 0.58(sys) +/- 0.40(abs) micro barns. The mean transverse momentum is 1.80 +/- 0.23(stat) +/- 0.16(sys) GeV/c.

5 data tables

Measured J/PSI distribution in PT for the e+e- channel. The value of B, the branching fraction to either electrons or muons is the average value from PDG : 5.9%.The rapidity range is -0.35<y<0.35. Incertainties are 1-sigma statistical errors on the (signal - background) net yield. There is a 10% overall absolute cross section normalization error in addition to the error given.

Measured J/PSI distribution in PT for the mu+mu- channel. The value of B, the branching fraction to either electrons or muons, is the average value from PDG: 5.9%.The rapidity range is -2.2<y<-1.2. Incertainties are 1-sigma statistical errors on the (signal - background) net yield.There is a 10% overall absolute cross section normalization error in addition to the error given.

J/PSI distribution in rapidity. The data at rapidity = 0 is from the electron arm, the data from the muon arm, corresponding to forward rapidity is divided in two bins.The value of B,the branching fraction to either electrons or muons, is 5.9%, the average value from PDG.Incertainties are 1-sigma statistical errors on the (signal - background) net yield.There is a 10% overall absolute cross section normalization error in addition to the error given.

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