국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	The Fall and the Rise of X-Rays from Dwarf Novae in Outburst: RXTE Observations of VW Hydri and WW Ceti
저자	Fertig, D.;; Mukai, K.;; Nelson, T.;; Cannizzo, J. K.
Keyword	ACCRETION DISKS;; BOUNDARY LAYERS;; CYGNUS CONSTELLATION;; DWARF NOVAE;; INFRARED RADIATION;; PHOTONS;; X RAY TIMING EXPLORER;; X RAYS
URL	http://hdl.handle.net/2060/20110023529
보고서번호	GSFC.JA.5443.2011
발행년도	2011
출처	NTRS (NASA Technical Report Server)
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 anti-correlated with the optical brightness. Here we present RXTE monitoring observations of two dwarf novae, VW Hyi and WW Cet, confirming the optical/X-ray anti-correlation 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 that only dwarf novae with a massive white dwarf may show these hard X-ray spikes.