[vsnet-alert 623] DX And possibly rising to outburst

[Taichi Kato <tkato>]

   AAVSO News Flash No. 83 (Dec. 9) tells that the long-period dwarf nova
DX And may be rising to outburst (due?).  Extract from the news flash:

-----------------------------------------------------------------------------   DX ANDROMEDAE

                     AAVSO Observer       
    UT        Mag.     Initials           

DEC 04.862    14.8       PYG   
DEC 09.0417   13.8       GRI   
DEC 09.1569   13.8       GRI   
-----------------------------------------------------------------------------   (PYG - G. Poyner, England; GRI - J. Griese, USA)

   The present early detection, if confirmed, of an outburst of DX And
might provide another (the others I mean recent events of CH UMa and GK Per)
excellent opportunity in probing the accretion disks in dwarf novae having
long orbital periods, whose outbursts seem to start from the inner part of
accretion disks.  GK Per and CH UMa all showed a "plateau" before reaching
maximum light, during which the heating wave seems to propagate through
the accretion disk inside-out (Kim et al. 1992).  Follow-up (multicolor
and time-resolved) observations are recommended at this moment of the event.

References (GK Per):

    A. Bianchini et al. 1986, A&A 160, 367 (analysis of light curve)
    S. -W. Kim et al. 1992, ApJ 384, 269 (dwarf nova-type model)

Regards,
Taichi Kato

VSNET Home Page

Return to Daisaku Nogami

---

vsnet-adm@kusastro.kyoto-u.ac.jp