[Date Prev][Date Next][Date Index]

(cba:news) V455 And and RX0232-37 (Joe Patterson) [2007-10-05T18:43:18Z]



Dear CBAers,

Well, the V455 And = HS2331 coverage continues good, though down from the frenetic pace of mid-September. The main periodic signals are basically standard fare for some of the WZ Sge stars: a strong signal
at Porb - with an origin still unknown - followed by a superhump.
No certifiable echo outbursts yet, but they could still come.

An important and unexpected wrinkle is the fast signal at 68 s. It's actually present throughout the outburst, and CBA data will specify what happens to the phase/period as the outburst fades. Keep that fast photometry coming (and by the way, if you possibly can, specify time to 6 decimal places (JD xxx.yyyyyy). Probably that sixth place is unimportant... but in playing with the data, I've noticed that roundoff errors can be detectable. For most of you, though, I imagine that the star's faintness, your readout time, and timekeeping accuracy will keep you away from studying this signal. That's fine - the most important lessons we're likely to learn from the eruption reside in the behavior of the slower periodic signals, and the eclipses. Cycle times around 40-60 s are likely to be just fine.

I've been delinquent in not writing about RX0232-37. This is a newly erupted dwarf nova, and Greg Bolt has found strong superhumps... so it's one of our friends. I believe it's still around V=11.7 or so, and may become quite an important star since it has to be quite nearby. This is really well placed for southern observers, and I fervently hope you'll spring to action pronto! (Even though I didn't.) The J2000 coords
are
                02h 32m 38.13s
               -37d 17m 54.7s

Find yourself a nice comp star and fire away! Having reached 10th mag or so, this star has great, great potential.

joe