https://doi.org/10.1140/epjc/s10052-018-6182-5
Regular Article - Theoretical Physics
in a hadronic medium
1
Instituto de Física, Universidade Federal da Bahia, Campus Ondina, Salvador, Bahia, 40170-115, Brazil
2
Instituto de Física, Universidade de São Paulo, Rua do Matão 1371, São Paulo, SP, 05508-090, Brazil
3
Institut de Physique Théorique, Université Paris Saclay, CEA, CNRS, 91191, Gif-sur-Yvette, France
4
SLAC Nacional Acelerator Laboratory, Stanford University, Stanford, CA, 94309, USA
* e-mail: navarra@if.usp.br
Received:
11
April
2018
Accepted:
23
August
2018
Published online:
19
September
2018
In this work we investigate the 
(called simply 
) abundance in the hot hadron gas produced in heavy ion collisions after the quark–gluon plasma phase. We use effective Lagrangians to calculate the thermally averaged cross sections of 
production in processes such as 
and also of its absorption in the corresponding inverse processes. We then solve the rate equation to follow the time evolution of the multiplicity. We find that, if we neglect the decay, the number of ’s produced at the end of the quark–gluon plasma phase remains almost constant during the hadron phase. The introduction of the decay in the rate equation leads to a suppression in the final yield by a factor two.
© The Author(s), 2018
