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Pion and kaon production in central Pb + Pb collisions at 20-A and 30-A-GeV: Evidence for the onset of deconfinement

The NA49 collaboration Alt, C. ; Anticic, T. ; Baatar, B. ; et al.
Phys.Rev. C77 (2008) 024903, 2008.
Inspire Record 762554 DOI 10.17182/hepdata.25169

Results on charged pion and kaon production in central Pb+Pb collisions at 20A and 30A GeV are presented and compared to data at lower and higher energies. A rapid change of the energy dependence is observed around 30A GeV for the yields of pions and kaons as well as for the shape of the transverse mass spectra. The change is compatible with the prediction that the threshold for production of a state of deconfined matter at the early stage of the collisions is located at low SPS energies.

13 data tables

Transverse mass spectra for pion production in the central rapidity region for collisions at 20 GeV per nucleon.

Transverse mass spectra for pion production in the central rapidity region for collisions at 30 GeV per nucleon.

Transverse mass spectra for kaon production in the central rapidity region for collisions at 20 GeV per nucleon.

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Charged pion production in 2 to 8 agev central au+au collisions

The E-0895 collaboration Klay, J.L. ; Ajitanand, N.N. ; Alexander, J.M. ; et al.
Phys.Rev. C68 (2003) 054905, 2003.
Inspire Record 622260 DOI 10.17182/hepdata.4989

Momentum spectra of charged pions over nearly full rapidity coverage from target to beam rapidity have been measured in the 0-5% most central Au+Au collisions in the beam energy range from 2 to 8 AGeV by the E895 Experiment. Using a thermal parameterization to fit the transverse mass spectra, rapidity density distributions are extracted. The observed spectra are compared with predictions from the RQMD v2.3 cascade model and also to a thermal model including longitudinal flow. The total 4$\pi$ yields of the charged pions are used to infer an initial state entropy produced in the collisions.

98 data tables

No description provided.

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Excitation function of K+ and pi+ production in Au + Au reactions at 2/A-GeV to 10/A-GeV

The E866 E917 collaborations Ahle, L. ; Akiba, Y. ; Ashktorab, K. ; et al.
Phys.Lett. B476 (2000) 1-8, 2000.
Inspire Record 508374 DOI 10.17182/hepdata.28038

Positive pion and kaon production from Au+Au reactions have been measured as a function of beam energy over the range 2.0-10.7~AGeV. Both the kaon and the pion production cross-sections at mid-rapidity are observed to increase steadily with beam kinetic energy. The ratio of K$^+$ to $\pi^+$ mid-rapidity yields increases from 0.0271$\pm0.0015\pm0.0014$ at 2.0~AGeV to 0.202$\pm0.005\pm0.010$ at 10.7~AGeV and is larger than the K$^+$/$\pi^+$ ratio from p+p reactions over the same beam energy region. There is no indication of an onset of any new production mechanism in heavy-ion reactions in this energy range beyond rescattering of hadrons.

4 data tables

The centrality selection at each beam energy is the most central 5% of the total interaction cross-section (SIG(C=interaction) = 6.8b). A single exponential function in MT was fit simultaneously to the two kaonspectra at each beam energy D2(N)/D(MT)/D(YRAP)/2/PI/MT=D(N)/D(YRAP)/2/PI/T/(T+ M(KAON))/EXP((MT-M(KAON))/T). The fits reproduce the spectra well with two free parameters, the inverse slope parameter T and the rapidity density, D(N)/D(YRAP)in that rapidity slice. The mid-rapidity range for 2, 4, 6, 8 AGeV is ABS((YRAP-Ynn)/Ynn) < 0.25, for 10.7 AGeV the width is ABS((YRAP-Ynn)/Ynn) < 0.125, where Ynn is mid-rapidity in the laboratory frame. The errors are statistical only. The 1.96, 4. and 10.74 GeV are E866 data, another - E917 data.

The centrality selection at each beam energy is the most central 5% of the total interaction cross-section (SIG(C=interaction) = 6.8b). A single exponential function in MT was fit simultaneously to the two kaonspectra at each beam energy D2(N)/D(MT)/D(YRAP)/2/PI/MT=D(N)/D(YRAP)/2/PI/T/(T+ M(KAON))/EXP((MT-M(KAON))/T). The fits reproduce the spectra well with two free parameters, the inverse slope parameter T and the rapidity density, D(N)/D(YRAP)in that rapidity slice. The mid-rapidity range for 2, 4, 6, 8 AGeV is ABS((YRAP-Ynn)/Ynn) < 0.25, for 10.7 AGeV the width is ABS((YRAP-Ynn)/Ynn) < 0.125, where Ynn is mid-rapidity in the laboratory frame. The errors are statistical only. The 1.96, 4. and 10.74 GeV are E866 data, another - E917 data.

The centrality selection at each beam energy is the most central 5% of the total interaction cross-section (SIG(C=interaction) = 6.8b). The spectra were fit with a scaled exponential, D2(N)/D(YRAP)/D(MT)/2/PI/MT=D(N)/D(YRAP)/2/PI/(T**(2-L))/GAMMA(2-L,M(PION)/T)/MT**L/EXP(MT/T), where GAMMA(2-L,M(PION)/T), the complementary incomplete gamma function, is introduced in the normalization so that D(N)/D(YRAP) is a fitted parameter (and other free parameters are L and T). The mid-rapidity range for 2, 4 (E866 data), 6, 8 AGeV (E917 data) beam energy is ABS((YRAP-Ynn)/Ynn) < 0.25, for 10.7 AGeV (E917 data) the width is ABS((YRAP-Ynn)/Ynn) <0.125, where Ynn is mid-rapidity in the laboratory frame. The errors are statistical only.

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Centrality dependence of pi+ / pi-, K+ / K-, p and anti-p production from s(NN)**(1/2) = 13-=GeV Au+Au collisions at RHIC

The PHENIX collaboration Adcox, K. ; Adler, S.S. ; Ajitanand, N.N. ; et al.
Phys.Rev.Lett. 88 (2002) 242301, 2002.
Inspire Record 568437 DOI 10.17182/hepdata.19421

Identified pi^[+/-] K^[+/-], p and p-bar transverse momentum spectra at mid-rapidity in sqrt(s_NN)=130 GeV Au-Au collisions were measured by the PHENIX experiment at RHIC as a function of collision centrality. Average transverse momenta increase with the number of participating nucleons in a similar way for all particle species. The multiplicity densities scale faster than the number of participating nucleons. Kaon and nucleon yields per participant increase faster than the pion yields. In central collisions at high transverse momenta (p_T greater than 2 GeV/c), anti-proton and proton yields are comparable to the pion yields.

21 data tables

Transverse momentum spectra for PI+ in the midrapidity range for the centrality region 0 to 5 PCT. Errors are combined statistical and systematics.

Transverse momentum spectra for PI- in the midrapidity range for the centrality region 0 to 5 PCT. Errors are combined statistical and systematics.

Transverse momentum spectra for K+ in the midrapidity range for the centrality region 0 to 5 PCT. Errors are combined statistical and systematics.

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Energy dependence of pion and kaon production in central Pb + Pb collisions

The NA49 collaboration Afanasiev, S.V. ; Anticic, T. ; Barna, D. ; et al.
Phys.Rev. C66 (2002) 054902, 2002.
Inspire Record 586383 DOI 10.17182/hepdata.31729

Measurements of charged pion and kaon production in central Pb+Pb collisions at 40, 80 and 158 AGeV are presented. These are compared with data at lower and higher energies as well as with results from p+p interactions. The mean pion multiplicity per wounded nucleon increases approximately linearly with s_NN^1/4 with a change of slope starting in the region 15-40 AGeV. The change from pion suppression with respect to p+p interactions, as observed at low collision energies, to pion enhancement at high energies occurs at about 40 AGeV. A non-monotonic energy dependence of the ratio of K^+ to pi^+ yields is observed, with a maximum close to 40 AGeV and an indication of a nearly constant value at higher energies.The measured dependences may be related to an increase of the entropy production and a decrease of the strangeness to entropy ratio in central Pb+Pb collisions in the low SPS energy range, which is consistent with the hypothesis that a transient state of deconfined matter is created above these energies. Other interpretations of the data are also discussed.

33 data tables

The centrality of the collisions expressed as a percentage of the inelastic cross section (7.15nb), and the mean numbers of wounded nuclei.

The inverse slope parameter of the fitted transverse mass spectra.

The rapidity density averaged over the rapidity interval -0.6 to 0.6.

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Strange meson enhancement in Pb Pb collisions

The NA44 collaboration Bearden, I. ; Boggild, H. ; Boissevain, J. ; et al.
Phys.Lett. B471 (1999) 6-12, 1999.
Inspire Record 504074 DOI 10.17182/hepdata.31360
4 data tables

Inverse slope paramters of the (1/MT)*DN/DMT distribution.

Rapidity distributions for K+ and K- production.. Statistical and systematic errors added in quadrature.

Rapidity distributions for PI+ and PI- production.. Statistical and systematic errors added in quadrature.

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Ratios of charged anti-particles to particles near mid-rapidity in Au + Au collisions at s(NN)**(1/2) = 130-GeV

The PHOBOS collaboration Back, B.B. ; Baker, M.D. ; Barton, D.S. ; et al.
Phys.Rev.Lett. 87 (2001) 102301, 2001.
Inspire Record 555572 DOI 10.17182/hepdata.41707

We have measured the ratios of antiparticles to particles for charged pions, kaons and protons near mid-rapidity in central Au+Au collisions at sqrt(s_NN) = 130 GeV. For protons, we observe pbar/p = 0.60 +/- 0.04 (stat.) +/- 0.06 (syst.) in the transverse momentum range 0.15 < p_T < 1.0 GeV/c. This leads to an estimate of the baryo-chemical potential mu_B of 45 MeV, a factor of 5-6 smaller than in central Pb+Pb collisions at sqrt(s_NN) = 17.2 GeV.

1 data table

130 GeV is sqrt(S) per nucleon-nucleon collision.


Charged particle production in S S collisions at 200-GeV/c per nucleon

The WA94 collaboration Andrighetto, A. ; Antinori, F. ; Bayes, A.C. ; et al.
Phys.Lett. B412 (1997) 148-154, 1997.
Inspire Record 460283 DOI 10.17182/hepdata.28242
3 data tables

Distributions are fitted with (1/MT**1.5)*DSIG/DMT = CONST*EXP(-MT/SLOPE).

1.54 GeV ratio is calculated from the fit to the MT distribution.

1.54 GeV ratio is calculated from the fit to the MT distribution.


Charged kaon and pion production at mid-rapidity in proton nucleus and sulphur nucleus collisions

The NA44 collaboration Boggild, H. ; Boissevain, J. ; Dodd, J. ; et al.
Phys.Rev. C59 (1999) 328-335, 1999.
Inspire Record 474831 DOI 10.17182/hepdata.25575

The NA44 collaboration has measured charged kaon and pion distributions at midrapidity in sulphur and proton collisions with nuclear targets at 200 and 450 GeV/c per nucleon, respectively. The inverse slopes of kaons are larger than those of pions. The difference in the inverse slopes of pions, kaons and protons, all measured in our spectrometer, increases with system size and is consistent with the buildup of collective flow for larger systems. The target dependence of both the yields and inverse slopes is stronger for the sulphur beam suggesting the increased importance of secondary rescattering for SA reactions. The rapidity density, dN/dy, of both K+ and K- increases more rapidly with system size than for pi+ in a similar rapidity region. This trend continues with increasing centrality, and according to RQMD, it is caused by secondary reactions between mesons and baryons. The K-/K+ ratio falls with increasing system size but more slowly than the pbar/p ratio. The pi-/pi+ ratio is close to unity for all systems. From pBe to SPb the K+/p ratio decreases while K-/pbar increases and ({K+*K-}/{p*pbar})**1/2 stays constant. These data suggest that as larger nuclei collide, the resulting system has a larger transverse expansion, baryon density and an increasing fraction of strange quarks.

8 data tables

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Pion and proton production in proton tungsten and sulphur tungsten interactions at 200-GeV/c per nucleon

The WA85 collaboration Antinori, F. ; Barnes, R.P. ; Bayes, A.C. ; et al.
Phys.Lett. B412 (1997) 407-413, 1997.
Inspire Record 459722 DOI 10.17182/hepdata.28265
4 data tables

No description provided.

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The slope evaluated from the D(N)/D(MT)/(MT**1.5) distribution (denoted as D(N)/D(MT)).

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Hadron yields and hadron spectra from the NA49 experiment

The NA49 collaboration Jones, P.G. ; Afanasev, S.V. ; Alber, T. ; et al.
Nucl.Phys. A610 (1996) 188C-199C, 1996.
Inspire Record 432742 DOI 10.17182/hepdata.36468
4 data tables

CENTRAL COLLISIONS, PRELIMINARY DATA.

CENTRAL COLLISIONS, PRELIMINARY DATA.

CENTRAL COLLISIONS, PRELIMINARY DATA.

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Hadron distributions: Recent results from the CERN experiment NA44

The NA44 collaboration Xu, N. ; Bearden, I.G. ; Boggild, H. ; et al.
Nucl.Phys. A610 (1996) 175C-187C, 1996.
Inspire Record 432743 DOI 10.17182/hepdata.36469
1 data table

CENTRAL COLLISIONS: SIG(TRIG)/SIG(GEOM)=10%.


Collective expansion in high-energy heavy ion collisions

The NA44 collaboration Bearden, I.G. ; Boggild, H. ; Boissevain, J. ; et al.
Phys.Rev.Lett. 78 (1997) 2080-2083, 1997.
Inspire Record 426801 DOI 10.17182/hepdata.52345
3 data tables

(1/MT)*d(N)/d(MT) = A *exp(-MT/SLOPE).

(1/MT)*d(N)/d(MT) = A *exp(-MT/SLOPE).

The SLOPE from the parameterization of (1/MT)*d(N)/d(MT) = A*exp(-MT/SLOPE)is fitted as follows SLOPE = CONST(C=1) + M(hadron)*CONST(C=2)**2.


Observation of enhanced subthreshold K+ production in central collisions between heavy nuclei

Miskowiec, D. ; Ahner, W. ; Barth, R. ; et al.
Phys.Rev.Lett. 72 (1994) 3650-3653, 1994.
Inspire Record 373335 DOI 10.17182/hepdata.19695
2 data tables

No description provided.

The total K+ cross section is determined by extrapolating and integrating the double differential cross section d2(sig)/d(p)/d(omega) over momentum and solid angle.


Charged hadron distributions in p A and A-A collisions at the CERN SPS

The NA44 collaboration Bearden, I.G. ; Dodd, J. ; Boggild, H. ; et al.
Nucl.Phys. A590 (1995) 523C-526C, 1995.
Inspire Record 407678 DOI 10.17182/hepdata.36504
2 data tables

No description provided.

PRELIMINARY DATA FOR CENTRAL EVENTS.


Recent results from NA44 and a review of HBT

The NA44 collaboration Jacak, B.V. ; Boggild, H. ; Boissevain, J. ; et al.
Nucl.Phys. A590 (1995) 215C-232C, 1995.
Inspire Record 407654 DOI 10.17182/hepdata.36517
1 data table

PRELIMINARY DATA FOR CENTRAL EVENTS.


Rapidity and transverse momentum distributions in 6.4-TeV S + Pb interactions from CERN EMU05 experiments. EMU-005 experiment

Iyono, A. ; Takahashi, Y. ; Gregory, J.C. ; et al.
Nucl.Phys. A544 (1992) 455C-458C, 1992.
Inspire Record 343252 DOI 10.17182/hepdata.36672
1 data table

EVENTS SELECTED FOR THE ANALYSIS ARE THOSE WITH CHARGED MULTIPLICITY MORE THAN 400 FOR CENTRAL S+PB COLLISIONS.


Production of pi+-, K+-, p, and anti-p in relativistic Au + Pt, Si + Pt, and p + Pt collisions

The E886 collaboration Diebold, G.E. ; Bassalleck, B. ; Burger, T. ; et al.
Phys.Rev. C48 (1993) 2984-2994, 1993.
Inspire Record 364483 DOI 10.17182/hepdata.26015
13 data tables

No description provided.

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Meson production in p + U, O + U and S + U interactions at 200-GeV/nucleon.

The NA38 collaboration Abreu, M.C. ; Baglin, C. ; Baldisseri, A. ; et al.
Z.Phys. C55 (1992) 365-371, 1992.
Inspire Record 344266 DOI 10.17182/hepdata.14583
6 data tables

No description provided.

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Meson production in oxygen uranium and sulfur uranium collisions at 200-GeV/nucleon

The NA38 collaboration Peralta, L. ;
Nucl.Phys. A525 (1991) 665C-668C, 1991.
Inspire Record 328951 DOI 10.17182/hepdata.36757
2 data tables

No description provided.

No description provided.


Measurement of kaons in the HELIOS experiment

The HELIOS collaboration van Hecke, Hubert ;
Nucl.Phys. A525 (1991) 227C-230C, 1991.
Inspire Record 301896 DOI 10.17182/hepdata.36791
5 data tables

No description provided.

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OBSERVATION OF SLOW PION PRODUCTION IN NUCLEUS NUCLEUS INTERACTIONS

Dubinina, A.I. ; Kolganova, E.D. ; Pozharova, E.A. ; et al.
JETP Lett. 48 (1988) 251-253, 1988.
Inspire Record 271948 DOI 10.17182/hepdata.16886
4 data tables

BEAM NUCLEUS ARE MIXTURE OF NE AND MG.

BEAM NUCLEUS ARE MIXTURE OF NE AND MG.

BEAM NUCLEUS ARE MIXTURE OF NE AND MG.

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PION AND KAON PRODUCTION IN COLLISIONS OF RELATIVISTIC NUCLEI WITH AN ENERGY OF 3.65-GEV/NUCLEON

Kurepin, A.B. ; Pantuev, V.S. ; Filippov, S.N. ;
JETP Lett. 47 (1988) 17-22, 1988.
Inspire Record 271432 DOI 10.17182/hepdata.16889
1 data table

No description provided.


INVESTIGATION OF THE MECHANISM OF RELATIVISTIC NUCLEUS INTERACTION FROM ANALYSIS OF C C COLLISIONS AT 4.2-GEV/C/NUCLEON. (IN RUSSIAN)

Ameev, S.Sh. ; Vinitsky, A.Kh. ; Izbasarov, M. ; et al.
Yad.Fiz. 41 (1985) 938-946, 1985.
Inspire Record 218881 DOI 10.17182/hepdata.2552
5 data tables

No description provided.

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Measurement of K mesons in collisions of relativistic carbon nuclei with led and copper nuclei

Gavrilov, O.K. ;
No Journal Information, 1984.
Inspire Record 1501546 DOI 10.17182/hepdata.76485
4 data tables

No description provided.

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