Chandra Observations of Old Novae

摘要

We present highlights of Chandra observations of two old novae, DQ Her and V603 Aql, with the main aim of improving our understanding of the underlying binaries decades after their respective nova eruptions. In DQ Her, we find a partial X-ray eclipse; it is likely that we observe photons scattered in an accretion disk wind. The X-ray spectrum of V603 Aql suggests an origin in multi-temperature plasma; while the low energy lines suggest modest density, the 6.4 keV Fe Kα line suggests that the hard continuum arises in a compact emission region. We also report on our searches for nebular X-ray emission around these old novae.