The Early X‐Ray Emission from V382 Velorum (Nova Velorum 1999): An Internal Shock Model

Abstract

We present the results of ASCA and RXT E observations of the early X-ray emission from the classical nova V382 Velorum. Its ASCA spectrum was hard (kT D 10 keV) with strong (1023 cm~2) intrinsic absorption. In the subsequent RXT E data, the spectra became softer, because of both a declining temperature and a diminishing column. We argue that this places the X-ray emission interior to the outer-most ejecta produced by V382 Vel in 1999, and therefore it must have been the result of a shock internal to the nova ejecta. The weakness of the Fe Ka lines probably indicates that the X-rayÈemitting plasmas are not in ionization equilibrium.