(cba:news) stars for november
Enrique de Miguel
edmiguel63 at gmail.com
Wed Nov 16 20:33:30 EST 2016
It's time to update our menu. Joe is going through some vision problems and has asked me to take care of the November menu. Well, here it goes, along with suggestions for removing some of our previous targets.
TARGETS TO BE REMOVED:
** RX And,
** V592 Cas (only positive superhumps this season),
** V Sge, LQ Peg, and LS Peg.
** BW Scl and AQ Men in the Southern skies.
STARS FOR NOVEMBER
** HS 0455+8315
High priority. A new eclipsing, negative superhumper. In addition to the signal associated with the superhump modulation, some of these targets show an additional signal (~4 days) which is believed to be a direct sign of the nodal precession of the accretion disk. For this target, this signal is expected at ~3.6 days, and my bet is that it's there. But we can only proof this if we follow the star along several nodal cycles. ~2 weeks of extensive coverage will tell. At this stage, only long runs are valuable.
** HS 0229+8016
A bright, alleged ZCam star, with brightness variations between ~13.8 and ~15.0 mag. Low-amplitude modulation of orbital nature (Porb ~ 3.88 hr). But in 2014 a short campaign showed another signal, possibly, a superhump. An intensive coverage ~1-2 week coverage should give us a clue. As
HS 0455+8315, the target is well placed in Northern skies for all-night runs. For these 2 targets, runs from both sides of the Atlantic would help.
** Intermediate polars (IPs)
Good time to get a few early-season runs on the following IPs: V1062 Tau, PQ Gem, V405 Aur, BG CMi and V667 Pup.
MU Cam is also a good choice, but Jou U. has done a good job, and we have now a good spin ephemeris that goes back to 2002. We can leave this target for a few weeks and resume coverage by the end of December.
We also need a few late-season runs on the "summer" IPs, mainly, AO Psc, V515 And, and V1033 Cas.
V647 Aur is slightly more demanding (it needs long runs).
And more demanding IPs are V902 Mon, eclipsing, equatorial IP; and Swift J0614.0+1709, a ~17-mag IP, but very rewarding.
Some additional (Southern) targets:
** CC Scl
** HZ Pup.
This is a faint (~17.0) intermediate polar (Pspin ~ 20.2 min). Not an easy target, but feasible for some of you in the morning sky. Great target if you can manage to get at least 2-3 h runs.
** T Pyx
~3 h runs now early in the season will be useful to keep track of the orbital signal
** ES Cet
A ~17.0 mag AM CVn star, with a fast orbital period (10.3 min) beautifully increasing with time. Berto and Gordon got some runs early in the season.
No need of dense coverage -just a few sporadic runs to keep track of the orbital signal.
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