The Effect of Mixing of the Ejecta on the Hard X-Ray Emissions from SN 1987A

We have calculated the X-ray and gamma-ray emissions expected from SN 1987A taking into account mixing of material in the ejecta. Nuclear gamma rays emitted by ^56^Co are scattered down to the hard X-ray band by multiple Compton scatterings. We have used Nomoto's 11E1Y6 model for the ejecta of SN 1987A. X-ray light curves in the 10-30 keV band and spectra above 20 keV calculated with an inner mixed region of 5+/-1 M_sun_ are consistent with the observations performed with the Ginga satellite and the KVANT/ROENTGEN mission. On the basis of this comparison, we discuss further evolutions of the hard X-ray, gamma-ray, and optical/infrared emissions.