Hydrodynamic Models of Classical Novae and Type I X-Ray Bursts
Keywords
X-rays, white dwarfs, temperature, hydrodynamics, photosphere, X-ray sources_s19 X-ray bursts, Faint blue stars , white dwarfs, degenerate stars, nuclei of planetary nebulae, Luminosities_s19 magnitudes_s19 effective temperatures, colors, and spectral classification, Hydrodynamics, Stellar atmospheres _s19 radiative transfer_s19 opacity and line formation
Abstract
Classical nova outbursts are powered by thermonuclear runaways that take place in the H-rich accreted envelopes of white dwarfs in close binary systems. Extensive numerical simulations of nova outbursts have shown that the accreted envelopes attain peak temperatures ranging between 108 and 4×108 K, for about several hundred seconds, and therefore, their ejecta is expected to show signatures of a significant nuclear activity. Indeed, it has been claimed that novae can play a certain role in the enrichment of the interstellar medium through a number of intermediate-mass elements. This includes 17O, 15N, and 13C, systematically overproduced in huge amounts with respect to solar abundances, with a lower contribution in a number of other species with A
