Measurement of charged particle multiplicities and densities in $pp$ collisions at $\sqrt{s}=7\;$TeV in the forward region

The LHCb collaboration Aaij, Roel ; Adeva, Bernardo ; Adinolfi, Marco ; et al.
Eur.Phys.J.C 74 (2014) 2888, 2014.
Inspire Record 1281685 DOI 10.17182/hepdata.63498

Charged particle multiplicities are studied in proton-proton collisions in the forward region at a centre-of-mass energy of $\sqrt{s} = 7\;$TeV with data collected by the LHCb detector. The forward spectrometer allows access to a kinematic range of $2.0<\eta<4.8$ in pseudorapidity, momenta down to $2\;$GeV/$c$ and transverse momenta down to $0.2\;$GeV/$c$. The measurements are performed using minimum-bias events with at least one charged particle in the kinematic acceptance. The results are presented as functions of pseudorapidity and transverse momentum and are compared to predictions from several Monte Carlo event generators.

0 data tables match query

On pion production intensities in hadron nucleus collisions.

Strugalska-Gola, E. ; Strugalski, Z. ; Sredniawa, B. ; et al.
JINR-E1-96-330, 1996.
Inspire Record 428911 DOI 10.17182/hepdata.39365

None

0 data tables match query

Di-jet production in gamma-gamma collisions at LEP2

The DELPHI collaboration Abdallah, J. ; Abreu, P. ; Adam, W. ; et al.
Eur.Phys.J.C 58 (2008) 531-541, 2008.
Inspire Record 806241 DOI 10.17182/hepdata.51688

The production of two high-p_T jets in the interactions of quasi-real photons in e+e- collisions at sqrt{s_ee} from 189 GeV to 209 GeV is studied with data corresponding to an integrated e+e- luminosity of 550 pb^{-1}. The jets reconstructed by the k_T cluster algorithm are defined within the pseudo-rapidity range -1 < eta < 1 and with jet transverse momentum, p_T, above 3 GeV/c. The differential di-jet cross-section is measured as a function of the mean transverse momentum ptmean of the jets and is compared to perturbative QCD calculations.

0 data tables match query

Excitation of the Delta (1232) resonance in proton - nucleus collisions

Trzaska, M. ; Pelte, D. ; Lemaire, M. -C. ; et al.
Z.Phys.A 340 (1991) 325-331, 1991.
Inspire Record 314551 DOI 10.17182/hepdata.15689

The excitation of theΔ resonance is observed in proton collisions on C, Nb and Pb targets at 0.8 and 1.6 GeV incident energies. The mass E0 and widthΓ of the resonance are determined from the invariant mass spectra of correlated (p, π±)-pairs in the final state of the collision: The mass E0 is smaller than that of the free resonance, however by comparing to intra-nuclear cascade calculations, this reduction is traced back to the effects of Fermi motion, NN scattering and pion reabsorption in nuclear matter.

0 data tables match query

Charged particle multiplicities in nuclear collisions at 200-GeV/N

The NA35 collaboration Bächler, J. ; Bartke, J. ; Bialkowska, H. ; et al.
Z.Phys.C 51 (1991) 157-162, 1991.
Inspire Record 320907 DOI 10.17182/hepdata.14983

Data on multiplicities of charged particles produced in proton-nucleus and nucleus-nucleus collisions at 200 GeV per nucleon are presented. It is shown that the mean multiplicity of negative particles is proportional to the mean number of nucleons participating in the collision both for nucleus-nucleus and proton-nucleus collisions. The apparent consistency of pion multiplicity data with the assumption of an incoherent superposition of nucleon-nucleon collisions is critically discussed.

0 data tables match query

Xi and Antixi production in 158-GeV/nucleon Pb + Pb collisions.

The NA49 collaboration Appelshäuser, H. ; Bächler, J. ; Bailey, S.J. ; et al.
Phys.Lett.B 444 (1998) 523-530, 1998.
Inspire Record 477539 DOI 10.17182/hepdata.31330

We report measurements of Xi and Xi-bar hyperon absolute yields as a function of rapidity in 158 GeV/c Pb+Pb collisions. At midrapidity, dN/dy = 2.29 +/- 0.12 for Xi, and 0.52 +/- 0.05 for Xi-bar, leading to the ratio of Xi-bar/Xi = 0.23 +/- 0.03. Inverse slope parameters fitted to the measured transverse mass spectra are of the order of 300 MeV near mid-rapidity. The estimated total yield of Xi particles in Pb+Pb central interactions amounts to 7.4 +/- 1.0 per collision. Comparison to Xi production in properly scaled p+p reactions at the same energy reveals a dramatic enhancement (about one order of magnitude) of Xi production in Pb+Pb central collisions over elementary hadron interactions.

0 data tables match query

Strangeness enhancement in central S + S collisions at 200-GeV/nucleon.

The NA35 collaboration Baechler, J. ; Bartke, J. ; Bialkowska, H. ; et al.
Nucl.Phys.A 525 (1991) 221C-226C, 1991.
Inspire Record 328899 DOI 10.17182/hepdata.36820

None

0 data tables match query

Measurement of charged particle multiplicities in $pp$ collisions at ${\sqrt{s} =7}$TeV in the forward region

The LHCb collaboration Aaij, R. ; Abellan Beteta, C. ; Adeva, B. ; et al.
Eur.Phys.J.C 72 (2012) 1947, 2012.
Inspire Record 1082369 DOI 10.17182/hepdata.65435

The charged particle production in proton-proton collisions is studied with the LHCb detector at a centre-of-mass energy of ${\sqrt{s} =7}$TeV in different intervals of pseudorapidity $\eta$. The charged particles are reconstructed close to the interaction region in the vertex detector, which provides high reconstruction efficiency in the $\eta$ ranges $-2.5&lt;\eta&lt;-2.0$ and $2.0&lt;\eta&lt;4.5$. The data were taken with a minimum bias trigger, only requiring one or more reconstructed tracks in the vertex detector. By selecting an event sample with at least one track with a transverse momentum greater than 1 GeV/c a hard QCD subsample is investigated. Several event generators are compared with the data; none are able to describe fully the multiplicity distributions or the charged particle density distribution as a function of $\eta$. In general, the models underestimate the charged particle production.

0 data tables match query

Centrality dependence of longitudinal and transverse baryon distributions in ultrarelativistic nuclear collisions

The E814 collaboration Barrette, J. ; Bellwied, R. ; Braun-Munzinger, P. ; et al.
Phys.Rev.C 50 (1994) 3047-3059, 1994.
Inspire Record 385496 DOI 10.17182/hepdata.25982

Inclusive double differential multiplicities d2N/dy dpt and related quantities have been measured for protons and deuterons produced in 14.6A GeV/c Si+Al and Si+Pb collisions using the E814 forward spectrometer at the AGS at BNL. Collision ‘‘centrality’’ is determined by measuring Nc, the total charged particle multiplicity in the pseudorapidity range 0.85<η<3.8. For both systems Si + Al and Si + Pb, an increase in the proton rapidity distribution dN/dy at midrapidity and a corresponding decrease at higher rapidities are observed with increasing Nc. For Si+Pb, Boltzmann slope parameters TB increase significantly in the most central collisions. The measured distributions exhibit a centrality dependence even when σ/σgeo≲10%, where full overlap between the Si and Pb nuclei occurs in a simple geometric picture. The proton rapidity distribution dN/dy is presented for the symmetric system Si+Al over the entire rapididty interval. The total number of protons, which is the integral of this quantity over rapidity, varies with Nc. Results are compared with various model calculations, mostly using the hadronic cascade codes ARC and RQMD. No significant nuclear transparency is observed, indicating that large baryon and energy densities are produced in these collisions.

0 data tables match query

Comparison of p + A and Si + Au collisions at 14.6-GeV/c

The E802 collaboration Abbott, T. ; Akiba, Y. ; Beavis, D. ; et al.
Phys.Rev.Lett. 66 (1991) 1567-1570, 1991.
Inspire Record 331219 DOI 10.17182/hepdata.19913

The production of π±,K±,p has been measured in p+Be and p+Au collisions for comparison with central Si+Au collisions. The inverse slope parameters T0 obtained by an exponential fit to the invariant cross sections in transverse mass are found to be, T0p,K+,ππ∼140–160 MeV in p+A collisions, whereas in central Si+Au collisions, T0p,K+∼200–220 MeV >T0ππ∼140–160 MeV at midrapidity. The π± and K+ distributions are shifted backwards in p+Au compared with p+Be. A gradual increase of (dn/dy)K+ per projectile nucleon is observed from p+Be to p+Au to central Si+Au collisions, while pions show no significant increase.

0 data tables match query