Weber, M.
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Interferometry results from the CERN WA98 experiment

Rosselet, L. ; Angelis, A.L.S. ; Doenni, P. ; et al.
Nucl.Phys.A 610 (1996) 256C-263C, 1996.
Inspire Record 432737 DOI 10.17182/hepdata.36463

None

1 data table
Table 1

PRELIMINARY DATA. THE DISTRIBUTION (1/PT)*D(N)/D(PT) HAS BEEN FITTED BY A FORMULA SQRT(MT)*K1(SLOPE*MT), WHERE K1 IS THE MAKDONALD FUNCTION.


Hadron distributions: Recent results from the CERN experiment NA44

The NA44 collaboration Xu, Nu ; Bearden, I.G. ; Bøggild, H. ; et al.
Nucl.Phys.A 610 (1996) 175C-187C, 1996.
Inspire Record 432743 DOI 10.17182/hepdata.36469

Proton distributions at midrapidity have been measured for 158A·GeV Pb+Pb collisions in the focusing spectrometer experiment NA44 at CERN. A high degree of nuclear stopping is found in the truly heavy ion collisions. Systematic results of single particle transverse momentum distributions of pions, kaons, and protons, of 200A·GeV S+S and 158A·GeV Pb+Pb central collisions will be addressed within the context of thermalization. By comparing these data with thermal and transport models, freeze-out parameters such as the temperature parameter T fo and mean collective flow velocity 〈β〉 are extracted. Preliminary results of the particle ratios of K − K + and p p are discussed in the context of cascade models of RQMD and VENUS.

1 data table
Table 1

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


Strangelet search and antinuclei production studies in Pb + Pb collisions

The NA52 (NEWMASS) collaboration Ambrosini, G. ; Appelquist, G. ; Arsenescu, R. ; et al.
Nucl.Phys.A 610 (1996) 306C-316C, 1996.
Inspire Record 432734 DOI 10.17182/hepdata.36512

We searched for long-lived strange quark matter particles, so-called strangelets , and studied particle and antiparticle production in Pb + Pb collisions at 158 GeV/ c per nucleon at zero degree production angle. We give upper limits for the production of strangelets covering a mass to charge ratio up to 120 GeV/ c 2 and lifetimes t lab > 1.2 μ s and plot invariant differential production cross sections as a function of rapidity for a variety of particles.

1 data table
Table 1

No description provided.


WA97 results on strangeness production in lead lead collisions at 158-A-GeV/c

The WA97 collaboration Andersen, E. ; Andrighetto, A. ; Antinori, F. ; et al.
Nucl.Phys.A 610 (1996) 165C-174C, 1996.
Inspire Record 432744 DOI 10.17182/hepdata.36503

Preliminary results from WA97 measurements on Λ, Ξ and Ω production in lead-lead and proton-lead collisions are presented, along with a comparison of WA97 proton-lead data with previous WA85 proton-tungsten results. The ratio Ω gX seems to be enhanced in lead initiated reactions compared to proton initiated reactions.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

PRELIMINARI DATA.

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Production of pi0, eta0, and omega0 mesons in the deep-fragmentation region by 70-GeV protons

The SPHINX collaboration Golovkin, S. ; Kozhevnikov, A. ; Kubarovsky, V. ; et al.
Phys.Atom.Nucl. 59 (1996) 1640-1642, 1996.
Inspire Record 433369 DOI 10.17182/hepdata.17188

None

1 data table
Table 1

No description provided.


Total and differential cross-sections of p + p ---> pi+ + d reactions down to 275-keV above threshold

The GEM collaboration Drochner, M. ; Ernst, J. ; Fortsch, S ; et al.
Phys.Rev.Lett. 77 (1996) 454-457, 1996.
Inspire Record 431032 DOI 10.17182/hepdata.19580

The p+p→π++d reaction is studied at excess energies between 0.275 and 3.86 MeV. Differential and total cross section were measured employing a magnetic spectrometer with nearly 4π acceptance in the center of mass system. The measured anisotropies between 0.008 and 0.29 indicate that the p wave is not negligible even so close to threshold. The data are compared to other data offering no evidence for charge symmetry breaking or time reversal violation. The s-wave and p-wave contributions at threshold are deduced.

1 data table
Table 1

The CONST is p-wave contribution to the cross section. The differential cross section is fitted usig the relations 4*pi*D(SIG)/D(OMEGA) = SIG + CONST*P2(COS(THETA)), where P2 denotes the Legendre polynomial.


Search for the production of pionium atoms near threshold

Betker, A.C. ; Cameron, J.M. ; Jacobs, W.W. ; et al.
Phys.Rev.Lett. 77 (1996) 3510-3513, 1996.
Inspire Record 429517 DOI 10.17182/hepdata.19609

We propose a model-independent method to extract a linear combination of the s-wave π−π scattering lengths by measuring the γγ decay branching ratio for a tagged sample of π+π− atoms (pionium). In the first experimental search for an appropriate tagging reaction, we observed σtot=76±21±11pb for free pion pair production in pd→3Heπ+π− 1.0 MeV above threshold. This result suggests a pionium production cross section ≲1pb.

2 data tables
Table 1

The cross section times acceptance.

Table 2

No description provided.


Subthreshold K+ production in proton nucleus collisions

De̹bowski, M. ; Barth, R. ; Boivin, M. ; et al.
Z.Phys.A 356 (1996) 313-325, 1996.
Inspire Record 432858 DOI 10.17182/hepdata.16477

Double differential K+cross sections have been measured in p+C collisions at 1.2, 1.5 and 2.5 GeV beam energy and in p+Pb collisions at 1.2 and 1.5 GeV. The K+ spectrum taken at 2.5 GeV can be reproduced quantitatively by a model calculation which takes into account first chance proton-nucleon collisions and internal momentum with energy distribution of nucleons according to the spectral function. At 1.2 and 1.5 GeV beam energy the K+ data excess significantly the model predictions for first chance collisions. When taking secondary processes into account the results of the calculations are in much better agreement with the data.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Subthreshold production of energetic pi- in relativistic Ne + NaF and Ni + Ni collisions

Gillitzer, A. ; Gilg, H. ; Handlos, M. ; et al.
Z.Phys.A 354 (1996) 3-4, 1996.
Inspire Record 429643 DOI 10.17182/hepdata.16504

The production of energetic π− at 0° has been measured in Ne+NaF and Ni+Ni collisions with incident energies between 1.3 and 2AGeV. In Ne+NaF collisions the investigation was extended to extreme subthreshold processes with lab momenta up to 4.5 GeV/c. In both systems at all incident energies the π− production cross sections deviate in a systematic way from thermal distributions.

2 data tables
Table 1

No description provided.

Table 2

Nucleus is NA F.


Precise pion electroproduction in the p (e, e-prime pi+) n reaction at W = 1125-MeV

Blomqvist, K.I. ; Boeglin, W.U. ; Böhm, R. ; et al.
Z.Phys.A 353 (1996) 415-421, 1996.
Inspire Record 428951 DOI 10.17182/hepdata.16502

The reactione+p →> e+π++n at c.m. energyW=1125MeV and momentum transfer Q2=0.117GeV2/c2 has been measured. The transverse and longitudinal structure functions have been separated by varying the polarization of the virtual photon (Rosenbluth plot) with a 3 to 4% error. In addition the longitudinal-transverse interference term has been determined measuring the right-left asymmetry with an accuracy of 3%. The experimental data are compared to model calculations, and the sensitivity of the results to the axial and pion formfactors is discussed.

6 data tables
Table 1

Angle PHI(P=4) is the angle between the scattering plane (defined by 1 and 3 particles) and the reaction plane (defined by 4 and 5 particles).

Table 2

Angle PHI(P=4) is the angle between the scattering plane (defined by 1 and 3 particles) and the reaction plane (defined by 4 and 5 particles).

Table 3

Angle PHI(P=4) is the angle between the scattering plane (defined by 1 and 3 particles) and the reaction plane (defined by 4 and 5 particles).

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