Peking Univ, Dept Phys, Beijing 100871, Peoples R China
; Peking Univ, MOE Lab Heavy Ion Phys, Beijing 100871, Peoples R China
; Peking Univ, Dept Phys, Beijing 100871, Peoples R China
; Chinese Acad Sci, Inst High Energy Phys, Beijing 100039, Peoples R China
; Natl Lab Heavy Ion Accelerator, Ctr Theoret Nucl Phys, Lanzhou 730000, Peoples R China
In-medium effects and neutrino trapping on K+ and K- production and K- condensation in supernova matter are investigated in a chiral hadronic model. Our results show that neutrino trapping shifts the critical density for K- condensation to higher density, the Q values for K+ and K- production are not sensitive to neutrino trapping, in-medium effects decrease the Q values for NN --> NNK+K- and DeltaN --> NNK- and increase those for NN --> NDeltaK(+), K(-)p --> Deltapi(0) and K(-)n --> Deltapi(-) as the density of supernova matter increases. Moreover, it is shown that neutrino trapping decreases the maximum masses of protoneutron stars compared with the neutrino-free case.