Investigating the microscopic properties of strongly interacting matter with HADES

• Authors: Tetyana Galatyuk , Manuel Lorenz
• Languages of publication: EN

Abstracts

EN

In the energy domain of 1–2 GeV kinetic energy per nucleon, HADES has measured rare and penetrating probes in elementary and heavy ion collisions. Our results demonstrate that electron pair emission in C+C collisions can essentially be explained as a superposition of independent N+N collisions. HADES results on e+e− production in Ar+KCl collisions, however, show a strong enhancement of the dilepton yield relative to a reference spectrum obtained from elementary nucleon-nucleon reactions, signal the onset of medium effects beyond the superposition of individual N+N collisions. Intriguing results where also obtained from the reconstruction of hadrons with open and hidden strangeness. Analyses of the experimentally obtained hadronic yields measured in Ar+KCl allows to extract the chemical freeze-out conditions in the T -µB phase diagram of strongly interacting matter. While the measured abundance of all reconstructed particles are well described assuming thermalization, the also reconstructed double strange baryon ≡− appears about ten times more abundant than expected. This result will be discussed in the context of the exploration of the nuclear matter phase diagram in the region of finite density. Further investigations to search for significant medium effects, will be followed over the coming years with an upgraded HADES detector.

Keywords

EN

di-electrons; strangeness

• Publisher: De Gruyter Open
• Journal: Open Physics
• Year: 2012
• Volume: 10
• Issue: 6
• Pages: 1295-1301

Dates

published

1 - 12 - 2012

online

4 - 12 - 2012

Contributors

author

Tetyana Galatyuk

author

Manuel Lorenz

• Goethe-University Frankfurt, 60438, Frankfurt am Main, Germany

References

• [1] J. Cleymans, H. Oeschler, K. Redlich, S. Wheaton, Phys. Rev. C 73, 034905 (2006) http://dx.doi.org/10.1103/PhysRevC.73.034905[Crossref]
• [2] Z. Fodor, S.D. Katz, J. High Energy Phys. 0404, 050 (2004) http://dx.doi.org/10.1088/1126-6708/2004/04/050[Crossref]
• [3] F. Karsch et al., Nucl. Phys. Proc. Suppl. 129, 614 (2003)
• [4] L. McLerran, R.D. Pisarski, Nucl. Phys. A 796, 83 (2007) http://dx.doi.org/10.1016/j.nuclphysa.2007.08.013[Crossref]
• [5] L. McLerran, Ch. Sasaki, K. Redlich, Nucl. Phys. A 824, 86 (2009) http://dx.doi.org/10.1016/j.nuclphysa.2009.04.001[Crossref]
• [6] A. Andronic et al., Nucl. Phys. A 837, 65 (2010) http://dx.doi.org/10.1016/j.nuclphysa.2010.02.005[Crossref]
• [7] D. Adamova et al. (CERES Collaboration), Phys. Lett. B 666, 425 (2006) http://dx.doi.org/10.1016/j.physletb.2008.07.104[Crossref]
• [8] R. Arnaldi et al. (NA60 Collaboration), Phys. Rev. Lett. 96, 162302 (2006) http://dx.doi.org/10.1103/PhysRevLett.96.162302[Crossref]
• [9] R.J. Porter et al. (DLS Collaboration), Phys. Rev. Lett. 79, 1229 (1997) http://dx.doi.org/10.1103/PhysRevLett.79.1229[Crossref]
• [10] G. Agakichiev et al. (HADES Collaboration), Phys. Lett. B 663, 43 (2008) http://dx.doi.org/10.1016/j.physletb.2008.03.062[Crossref]
• [11] G. Agakichiev et al. (HADES Collaboration), Phys. Rev. Lett. 98, 052302 (2007) http://dx.doi.org/10.1103/PhysRevLett.98.052302[Crossref]
• [12] G. Agakichiev et al. (HADES Collaboration), Phys. Lett. B 690, 118 (2010) http://dx.doi.org/10.1016/j.physletb.2010.05.010[Crossref]
• [13] T. Galatyuk et al. (HADES Collaboration), PoS CPOD2009, 045 (2009)
• [14] J. Zhang, D. Gupta, C. Gale, Phys. Rev. C 50, 1617 (1994) http://dx.doi.org/10.1103/PhysRevC.50.1617[Crossref]
• [15] B. Kämpfer, L.P. Kaptari, Nucl. Phys. A 764, 338 (2006) http://dx.doi.org/10.1016/j.nuclphysa.2005.10.007[Crossref]
• [16] R. Shyam, U. Mosel, Phys. Rev. C 67, 065202 (2003) http://dx.doi.org/10.1103/PhysRevC.67.065202[Crossref]
• [17] R. Shyam, U. Mosel, arXiv:1006.3873 [hep-ph]
• [18] T. Galatyuk et al. (HADES Collaboration), PoS CPOD2009, 045 (2009)
• [19] G. Agakichiev et al. (HADES Collaboration), Phys. Rev. C 84, 014902 (2011) http://dx.doi.org/10.1103/PhysRevC.84.014902[Crossref]
• [20] R. Nasseripour et al., Phys. Rev. Lett. 99, 272302 (2007) http://dx.doi.org/10.1103/PhysRevLett.99.262302[Crossref]
• [21] M.H. Wood et al., Phys. Rev. C 78, 015201 (2008) http://dx.doi.org/10.1103/PhysRevC.78.015201[Crossref]
• [22] M. Kotulla et al. (TAPS Collaboration), Phys. Rev. Lett. 100, 192302 (2008) http://dx.doi.org/10.1103/PhysRevLett.100.192302[Crossref]
• [23] G. Agakichiev et al. (HADES Collaboration), arXiv:1112.3607 [nucl-ex]
• [24] M. Berlowski et al. (CELSIUS/WASA Collaboration), Phys. Rev. D 77, 032004 (2008) http://dx.doi.org/10.1103/PhysRevD.77.032004[Crossref]
• [25] A.P. Raposo, H.J. Weber, D.E. Alvarez-Castillo, M. Kirchbach, Cent. Eur. J. Phys. 5, 253 (2007) http://dx.doi.org/10.2478/s11534-007-0018-5[Crossref]
• [26] R. Averbeck, R. Holzmann, V. Metag, R.S. Simon, Phys. Rev. C 67, 024903 (2003) http://dx.doi.org/10.1103/PhysRevC.67.024903[Crossref]
• [27] F. Becattini, M. Gazdzicki, A. Keranen, J. Manninen, R. Stock, Phys. Rev. C 69, 024905 (2004) http://dx.doi.org/10.1103/PhysRevC.69.024905[Crossref]
• [28] G. Agakishiev et al. (HADES Collaboration), Eur. Phys. J. A 47, 21 (2011) http://dx.doi.org/10.1140/epja/i2011-11021-8[Crossref]
• [29] S. Wheaton, J. Cleymans, Comput. Phys. Commun. 180, 84 (2009) http://dx.doi.org/10.1016/j.cpc.2008.08.001[Crossref]
• [30] J. Adams et al. (STAR Collaboration), Phys. Rev. Lett. 98, 062301 (2007) http://dx.doi.org/10.1103/PhysRevLett.98.062301[Crossref]
• [31] F. Antinori et al. (NA57 Collaboration), Phys. Lett. B 595, 68 (2004) http://dx.doi.org/10.1016/j.physletb.2004.05.025[Crossref]
• [32] P. Chung et al. (E895 Collaboration), Phys. Rev. Lett. 91, 202301 (2003) http://dx.doi.org/10.1103/PhysRevLett.91.202301[Crossref]
• [33] E.E. Kolomeitsev, B. Tomasik, J. Phys. G 36, 095104 (2009) http://dx.doi.org/10.1088/0954-3899/36/9/095104[Crossref]
• [34] H. Oeschler et al., arXiv:0908.1771 [nucl-ex]
• [35] R. Arnaldi et al. (NA60 Collaboration), Eur. Phys. J. C 61 (2009)
• [36] A. Forster et al. (KaoS Collaboration), Phys. Rev. C 75, 024906 (2007) http://dx.doi.org/10.1103/PhysRevC.75.024906[Crossref]
• [37] I. Frohlich et al., Eur. Phys. J. A 45, 401 (2010) http://dx.doi.org/10.1140/epja/i2010-11012-3[Crossref]
• [38] M. Lorenz et al. (HADES Collaboration), PoS BORMIO2010 038 (2010)

Identifiers

DOI

10.2478/s11534-012-0075-2