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The Multiplicity dependence of inclusive p(t) spectra from p-p collisions at s**(1/2) = 200-GeV

The STAR collaboration Adams, J. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev.D 74 (2006) 032006, 2006.
Inspire Record 719969 DOI 10.17182/hepdata.102084

We report measurements of transverse momentum $p_t$ spectra for ten event multiplicity classes of p-p collisions at $\sqrt{s} = 200$ GeV. By analyzing the multiplicity dependence we find that the spectrum shape can be decomposed into a part with amplitude proportional to multiplicity and described by a L\'evy distribution on transverse mass $m_t$, and a part with amplitude proportional to multiplicity squared and described by a gaussian distribution on transverse rapidity $y_t$. The functional forms of the two parts are nearly independent of event multiplicity. The two parts can be identified with the soft and hard components of a two-component model of p-p collisions. This analysis then provides the first isolation of the hard component of the $p_t$ spectrum as a distribution of simple form on $y_t$.

5 data tables

FIG. 1: Corrected and normalized charged-particle spectra on transverse momentum $p_t$ (left) and transverse rapidity $y_t$ (right) for 10 event multiplicity classes, displaced upward by successive factors 40 relative to $\hat{n}_{ch}$ = 1 at bottom. Solid curves represent reference function $n_s/n_{ch} · S_0(y_t)$ (cf.Sec. IV C). Dotted curves are spline fits to guide the eye.

FIG. 1: Corrected and normalized charged-particle spectra on transverse momentum $p_t$ (left) and transverse rapidity $y_t$ (right) for 10 event multiplicity classes, displaced upward by successive factors 40 relative to $\hat{n}_{ch}$ = 1 at bottom. Solid curves represent reference function $n_s/n_{ch} · S_0(y_t)$ (cf.Sec. IV C). Dotted curves are spline fits to guide the eye.

FIG. 2. Left: Relative residuals from power-law fits to $p_{t}$ spectra in Fig. 1. The hatched band represents the expected statistical errors for STAR data. Right: Exponents $n$ from power-law fits to data (solid points) and to corresponding twocomponent fixed-model functions (open circles, see Sec. VI) compared to the two-component fixed-model Lévy exponent $12.8 \pm 0.15$ (hatched band). NOTE 1: For points with invisible error bars, the point size was considered as an absolute upper limit for the uncertainty. NOTE 2: The "data_stat" uncertainty corresponds to the expected statistical error (hatched band).

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Measurement of long-range pseudorapidity correlations and azimuthal harmonics in $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV proton-lead collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.C 90 (2014) 044906, 2014.
Inspire Record 1315325 DOI 10.17182/hepdata.66357

Measurements of two-particle correlation functions and the first five azimuthal harmonics, $v_1$ to $v_5$, are presented, using 28 $\mathrm{nb}^{-1}$ of $p$+Pb collisions at a nucleon-nucleon center-of-mass energy of $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV measured with the ATLAS detector at the LHC. Significant long-range "ridge-like" correlations are observed for pairs with small relative azimuthal angle ($|\Delta\phi|<\pi/3$) and back-to-back pairs ($|\Delta\phi| > 2\pi/3$) over the transverse momentum range $0.4 < p_{\rm T} < 12$ GeV and in different intervals of event activity. The event activity is defined by either the number of reconstructed tracks or the total transverse energy on the Pb-fragmentation side. The azimuthal structure of such long-range correlations is Fourier decomposed to obtain the harmonics $v_n$ as a function of $p_{\rm T}$ and event activity. The extracted $v_n$ values for $n=2$ to 5 decrease with $n$. The $v_2$ and $v_3$ values are found to be positive in the measured $p_{\rm T}$ range. The $v_1$ is also measured as a function of $p_{\rm T}$ and is observed to change sign around $p_{\rm T}\approx 1.5$-2.0 GeV and then increase to about 0.1 for $p_{\rm T}>4$ GeV. The $v_2(p_{\rm T})$, $v_3(p_{\rm T})$ and $v_4(p_{\rm T})$ are compared to the $v_n$ coefficients in Pb+Pb collisions at $\sqrt{s_{\mathrm{NN}}} =2.76$ TeV with similar event multiplicities. Reasonable agreement is observed after accounting for the difference in the average $p_{\rm T}$ of particles produced in the two collision systems.

92 data tables

The distributions of $N_{ch}^{rec}$ for MB and MB+HMT after applying an event-by-event weight, errors are statistical.

The distributions of $E_{T}^{Pb}$ [GeV] for MB and MB+HMT after applying an event-by-event weight, errors are statistical.

Per-trigger yield in 2D, $Y$($\Delta\phi$,$\Delta\eta$), for events with $E_{T}^{Pb} <$ 10 GeV and $N_{ch}^{rec} \geq$ 200 and recoil-subtracted per-trigger yield, $Y^{sub}$($\Delta\phi$,$\Delta\eta$) for events with $N_{ch}^{rec} \geq$ 200. Errors are statistical.

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QCD studies with e+ e- annihilation data at 172-GeV to 189-GeV.

The OPAL collaboration Abbiendi, G. ; Ackerstaff, K. ; Akesson, P.F. ; et al.
Eur.Phys.J.C 16 (2000) 185-210, 2000.
Inspire Record 513476 DOI 10.17182/hepdata.49000

We have studied hadronic events from e+e- annihilation data at centre-of-mass energies of sqrt{s}=172, 183 and 189 GeV. The total integrated luminosity of the three samples, measured with the OPAL detector, corresponds to 250 pb^-1. We present distributions of event shape variables, charged particle multiplicity and momentum, measured separately in the three data samples. From these we extract measurements of the strong coupling alpha_s, the mean charged particle multiplicity <nch> and the peak position xi_0 in the xi_p=ln(1/x_p) distribution. In general the data are described well by analytic QCD calculations and Monte Carlo models. Our measured values of alpha_s, <nch> and xi_0 are consistent with previous determinations at sqrt{s}=MZ.

20 data tables

Distribution of Thrust.

Distribution of Thrust Major.

Distribution of Thrust Minor.

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Study of the inclusive reaction Mg + Mg ---> pi- + X at a momentum of 4.3-GeV/c per incident nucleon

Chkhaidze, L. ; Dzhobava, T. ; Kharkhelauri, L. ; et al.
J.Phys.G 22 (1996) 641-651, 1996.
Inspire Record 431133 DOI 10.17182/hepdata.43780

A detailed study of pion production in central Mg - Mg collisions at a momentum of 4.3 GeV/c per incident nucleon was carried out using the GIBS set-up. It has been shown that the dependence of the average kinematical characteristics ( and ) of mesons on multiplicity differs from that for NN collisions at the same energy, which is due to nuclear effects. The temperatures of mesons have been estimated using two different selection criteria: in the rapidity interval and at angles in the CMS. A satisfactory fit for mesons can be achieved by using a form involving two temperatures and . The relative yield of the high-temperature component is . The results obtained by the intranuclear cascade model CASIMIR coincide with the experimental data estimated with both methods. From the analysis of angular distributions of mesons the anisotropy coefficient a was obtained. The anisotropy coefficient increases linearly with the kinetic energy (in the CMS). CASIMIR reproduces the increase of a with , but the slope is less steep than from experimental results.

2 data tables

The average kinematical characteristics of the PI- production.

The mean YRAP and its dispersion in various PT intervals.


NUCLEUS IS NUCLEAR PHOTOEMULSION. EVENT WITH A TOTAL CHARGE OF ALL SPECTATOR FRAGMENTS OF A PROJECTILE = 0.

NUCLEUS IS NUCLEAR PHOTOEMULSION. EVENT WITH A TOTAL CHARGET OF ALL SPECTATOR FRAGMENTS OF A PROJECTILE = 1.

NUCLEUS IS NUCLEAR PHOTOEMULSION.

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Comparative Characteristics of Central and Noncentral C C Interactions at 4.2-{GeV} Per Nucleon

Agakishiev, G.N. ; Backovic, S. ; Boldea, V. ; et al.
Sov.J.Nucl.Phys. 51 (1990) 481-485, 1990.
Inspire Record 285507 DOI 10.17182/hepdata.17258

None

5 data tables

No description provided.

No description provided.

P - IS PROTON-PARTICIPANTS, ITS NUMBER WAS DEFINED AS FOLLOWS: N(P)=N+ - N - N(S,P) - N(S,T), WHERE N+ , N- - NUMBER OF MULT(CHARGED) PARTICLES WITH Z=+1 AND Z=-1, N(S,P), N(S,T) - NUMBER OF STRIPPING PARTICLES WITH Z=1 FROM PROJECTILE (P>3 GEV, THETA<4 DEG) AND TARGET (P<0.3 GEV FOR PROTONS).

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Production of $\Lambda$ Hyperons and $K^0(s$) Mesons in Annihilation of Anti-protons in $^{4}$He Nuclei at 600-{MeV}/$c$

Batusov, Yu.A. ; Bunyatov, S.A. ; Falomkin, I.V. ; et al.
Sov.J.Nucl.Phys. 50 (1989) 945-948, 1989.
Inspire Record 280132 DOI 10.17182/hepdata.39439

None

4 data tables

43 EVENTS WITH LAMBDA, 54 EVENTS WITH KS.

43 EVENTS WITH LAMBDA, 54 EVENTS WITH KS.

43 EVENTS WITH LAMBDA, 54 EVENTS WITH KS. D(N)/D(P) WAS FITTED BY P**2*EXP(-SLOPE*EKIN).

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Multiplicity, Momentum and Angular Characteristics of $\pi^-$ Mesons for $p$ C, $d$ C, $\alpha$ C and C C Interactions at 4.2-{GeV}/$c$ Per Nucleon

The Alma Ata-Baku-Belgrade-Bucharest-Dubna-Kishinev-Leipzig- Moscow-Prague-Samarkand-Sofiya-Tashkent-Tbilisi-Ulan Bator-Varna collaboration Agakishiev, G.N. ; Akhababian, N. ; Armutliisky, D. ; et al.
Z.Phys.C 27 (1985) 177, 1984.
Inspire Record 203342 DOI 10.17182/hepdata.1999

Light ion collisions with carbon target at 4.2 GeV/c/N are studied. Pion multiplicity distributions, momentum and angular spectra are analysed. These data are described in terms of models assuming independent interactions of nucleons from the projectile nucleus with the target.

18 data tables

No description provided.

No description provided.

No description provided.

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PRODUCTION OF NEUTRAL STRANGE PARTICLES IN ANTI-P HE-4 ANNIHILATION AT 600-MEV/C. (IN RUSSIAN)

Batusov, Yu.A. ; Balestra, F. ; Barbieri, Riccardo ; et al.
DUBNA JINR - N7-88 (88,REC.FEB.89) 23-31, 1988.
Inspire Record 271238 DOI 10.17182/hepdata.38297

None

5 data tables

No description provided.

No description provided.

No description provided.

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RESULTS ON LAMBDA(c)+, D(s)+, D0 AND D+ PRODUCTION PROPERTIES IN 230-GeV/c pi- Cu INTERACTIONS FROM THE NA32 EXPERIMENT

The ACCMOR collaboration Barlag, S. ; Becker, H. ; Bohringer, T. ; et al.
CERN-EP/88-104, 1988.
Inspire Record 264995 DOI 10.17182/hepdata.12879

None

33 data tables

AUTHORS FIT D2(SIG)/D(XL)/D(PT**2) BY (1-XL)**POWER*EXP(-SLOPE*PT**2).

AUTHORS FIT D2(SIG)/D(XL)/D(PT**2) BY (1-XL)**POWER*EXP(-SLOPE*PT**2).

AUTHORS FIT D2(SIG)/D(XL)/D(PT**2) BY (1-XL)**POWER*EXP(-SLOPE*PT**2).

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