K−/K+ ratio at GSI in hot and dense matter

The K - /K + ratio in heavy-ion collisions at GSI energies is studied including the properties of the participating hadrons in hot and dense matter. The determination of the temperature and chemical potential at freeze-out conditions compatible with the ratio K - /K + is very delicate, and depends on the approach adopted for the antikaon self-energy. Three approaches for the K- self-energy are considered: non-interacting K-, on-shell self-energy and single-particle spectral density. With respect to the on-shell approach, the use of an energy dependent K spectral density, including both s- and p-wave components of the K N interaction, lowers considerably the freeze-out temperature and gives rise to the 'broad-band equilibration' advocated by Brown, Rho and Song.

[1]  A. Polls,et al.  K^-/K^+ ratio in heavy-ion collisions with an antikaon self-energy in hot and dense matter , 2003, nucl-th/0302082.

[2]  H. Oeschler,et al.  What determines the K- multiplicity at energies around (1-2)A GeV? , 2001, Physical review letters.

[3]  F. Laue,et al.  Kaon and antikaon production in dense nuclear matter , 2002 .

[4]  A. Polls,et al.  Antikaon nuclear potential in hot and dense matter , 2002, nucl-th/0202057.

[5]  H. Oeschler.  Survey of experimental data , 2002, nucl-ex/0202003.

[6]  B. Zou,et al.  Theoretical formalism and Monte Carlo study of partial wave analysis for J/Psi --> p?omegaTheoretical formalism and Monte Carlo study of partial wave analysis for J/Psi --> pomega , 2002 .

[7]  G. Brown,et al.  Broad band equilibration of strangeness , 2001, nucl-th/0104022.

[8]  C. Korpa,et al.  Self-consistent propagation of hyperons and antikaons in nuclear matter based on relativistic chiral SU(3) dynamics , 2001, nucl-th/0105067.

[9]  A. Polls,et al.  Partial wave contributions to the antikaon potential at finite momentum , 2000, nucl-th/0007042.

[10]  F. Laue,et al.  First measurement of antikaon phase-space distributions in nucleus–nucleus collisions at subthreshold beam energies , 2000, nucl-ex/0010013.

[11]  G. E. Brown,et al.  Strangeness equilibration at GSI energies , 2000, nucl-th/0010008.

[12]  P. Senger.  Strange Mesons in Dense Nuclear Matter , 2000, nucl-ex/0010012.

[13]  J. Schaffner-Bielich,et al.  Medium modified cross sections, temperature and finite momentum effects for antikaon production in heavy-ion collisions☆ , 1999, nucl-th/9907095.

[14]  J. Dabrowski.  Isospin dependence of the single particle potential of the Sigma hyperon in nuclear matter , 1999 .

[15]  J. Cleymans,et al.  Chemical and thermal freezeout parameters from 1-A/GeV to 200-A/GeV , 1999, nucl-th/9903063.

[16]  F. Laue,et al.  Medium Effects in Kaon and Antikaon Production in Nuclear Collisions at Subthreshold Beam Energies , 1999, nucl-ex/9901005.

[17]  J. Cleymans,et al.  Influence of impact parameter on thermal description of relativistic heavy ion collisions at (1-2)A GeV , 1998, nucl-th/9809027.

[18]  J. Cleymans,et al.  Thermal model analysis of particle ratios in Ni+Ni experiments using exact strangeness conservation , 1997, nucl-th/9711066.

[19]  P. Beckerle,et al.  Subthreshold Production of Kaons and Antikaons in Nucleus-Nucleus Collisions at Equivalent Beam Energies , 1997 .

[20]  A. Gal,et al.  An Effective equation of state for dense matter with strangeness , 1997, nucl-th/9704013.

[21]  J. Mares,et al.  Constraints on Sigma nucleus dynamics from Dirac phenomenology of Sigma- atoms , 1995, nucl-th/9505003.

[22]  J. Speth,et al.  K- N interaction in the meson exchange framework , 1990 .