The fall and the rise of X-rays from dwarf novae in outburst: RXTE observations of VW hydri and WW Ceti

D. Fertig, K. Mukai, Thomas J Nelson, J. K. Cannizzo

Research output: Contribution to journalArticlepeer-review

18 Scopus citations

Abstract

In a dwarf nova, the accretion disk around the white dwarf is a source of ultraviolet, optical, and infrared photons, but is never hot enough to emit X-rays. Observed X-rays instead originate from the boundary layer between the disk and the white dwarf. As the disk switches between quiescence and outburst states, the 2-10 keV X-ray flux is usually seen to be anticorrelated with the optical brightness. Here, we present RXTE monitoring observations of two dwarf novae, VW Hyi and WW Cet, confirming the optical/X-ray anticorrelation in these two systems. However, we do not detect any episodes of increased hard X-ray flux on the rise (out of two possible chances for WW Cet) or the decline (two for WW Cet and one for VW Hyi) from outburst, attributes that are clearly established in SS Cyg. The addition of these data to the existing literature establishes the fact that the behavior of SS Cyg is the exception, rather than the archetype as is often assumed. We speculate on the origin of the diversity of behaviors exhibited by dwarf novae, focusing on the role played by the white dwarf mass.

Original languageEnglish (US)
Pages (from-to)1054-1061
Number of pages8
JournalPublications of the Astronomical Society of the Pacific
Volume123
Issue number907
DOIs
StatePublished - Sep 2011

Fingerprint

Dive into the research topics of 'The fall and the rise of X-rays from dwarf novae in outburst: RXTE observations of VW hydri and WW Ceti'. Together they form a unique fingerprint.

Cite this