Eur. Phys. J. A 9, 397-410
Production of charged pions, kaons and antikaons
in relativistic
and
collisions
F. Laue1 - I. Böttcher3 - M. Debowski5 - A. Förster2 - E. Grosse6,7 - P. Koczon1 - B. Kohlmeyer3 - M. Mang1 - M. Menzel3 - L. Naumann6 - H. Oeschler2 - F. Pühlhofer3 - E. Schwab1 - P. Senger1
- Y. Shin4 - J. Speer3 - H. Ströbele4 - C. Sturm2 - G. Surówka1,5 - F. Uhlig2 - A. Wagner6 - W. Walus5
(KaoS Collaboration)
1 Gesellschaft für Schwerionenforschung, D-64220 Darmstadt, Germany
2 Technische Universität Darmstadt, D-64289 Darmstadt, Germany
3 Phillips Universität, D-35037 Marburg, Germany
4 Johann Wolfgang Goethe Universität, D-60325 Frankfurt am Main, Germany
5 Jagiellonian University, PL-30059 Kraków, Poland
6 Forschungszentrum Rossendorf, D-01314 Dresden, Germany
7 Technische Universität Dresden, D-01314 Dresden, Germany
Received: 10 December 1999
Communicated by D. Guerreau
Abstract
Production cross-sections of charged pions,
kaons and antikaons have been measured in C+C and C+Au collisions
at beam energies of 1.0 and 1.8 AGeV for different polar emission angles.
The kaon and antikaon energy spectra can be described by Boltzmann distributions
whereas the pion spectra exhibit an additional enhancement at low energies.
The pion multiplicity per participating nucleon
is a factor of about 3 smaller in C+Au than in C+C collisions at 1.0 AGeV
whereas it differs only little for the C and the
Au target at a beam energy of 1.8 AGeV.
The K+ multiplicities per participating nucleon M(K+)/
are independent of the target size at 1 AGeV and at 1.8 AGeV.
The K- multiplicity per participating nucleon
M(K-)/
is reduced by
a factor of about 2 in C+Au as compared to C+C collisions at 1.8 AGeV.
This effect might be caused by the absorption of antikaons
in the heavy target nucleus.
Transport model calculations underestimate the K-/K+ ratio for
C+C collisions at 1.8 AGeV by a factor of about 4 if in-medium modifications
of K-mesons are neglected.
PACS
25.75.Dw Particle and resonance production
Copyright Società Italiana di Fisica, Springer-Verlag 2000