What we have learned from the brightest novae in the X-ray band in the Magellanic Clouds
Abstract
Classical and recurrent novae in the Magellanic Clouds offer the advantage of following nova eruptions at known distance. In the soft X-rays, the lack of conspicuous interstellar absorption towards the Clouds compensates for their distance, on average 10 times larger than known Galactic novae, so high resolution X-ray spectra of good quality can be obtained. In this talk I will review the results of two works done with two different teams of coauthors, on Nova LMC 2009a and on Nova SMC 2016a, respectively. N LMC 2009a was a luminous recurrent nova and had a relatively slow X-ray development, with spectra in which the absorption features are less deep than in most novae. The second nova, N SMC 2016a, was unusually luminous at all wavelengths, and may be the prototype of a rare class of "hyperluminous" novae. Its spectra shows very deep, blue-shifted absorption features, which evolved quite rapidly. The peak effective temperatures we derived for the white dwarfs of both novae imply massive objects, most likely exceeding 1.2 solar masses. I will show what we learned about the chemistry and physics of these novae that exploded in lower metallicity environment than the Galactic ones. I will also discuss what we expect to be able to learn with Athena.
- Publication:
-
42nd COSPAR Scientific Assembly
- Pub Date:
- July 2018
- Bibcode:
- 2018cosp...42E2519O