[Message Prev][Message Next][Thread Prev][Thread Next][Message Index][Thread Index]

[vsnet-obs 3160] humps in wx ceti



             WX CETI, GETTING MAYBE A LITTLE LESS BASHFUL

Photoelectric photometry on the CTIO 1-m by Jonathan Kemp and Susan
Kassin showed 0.25 mag superhumps in WX Ceti on the night of July
17/18.  Thus the present outburst is very likely to be a supermax, as
suspected by Kato (yesterday's vsnet).  Congratulations
K(emp)K(assin)K(ato), and of course also Berto Monard and Albert Jones
who rang the alarm.

A July supermax isn't perfect (we'd really like October), but it's
still the best seasonal timing WX Cet has ever delivered.  O'Donoghue
et al. (1991; MNRAS 250, 363) struggled valiantly to find the superhump
period from single-site observations in early June 1989.  Their best-
fit periods were in the range 70-80 min, an awfully interesting range!
But these were based on observations of only ~2 hr/night (because of
the unfavorable location of Cetus in June), far too brief to identify
the period securely.  Thus the superhump period remains unknown.

Now we can fix that.  But it probably requires a multi-longitude
collaboration - because even now we can only get 4-hour runs on the
star, still uncomfortably short.  We would love to hear from other
observers who are able to get superhump timings.  At magnitude 11.7 and
with a full amplitude of 0.25 mag, the project may even be feasible for
very experienced visual observers.

WX Cet is sometimes classified among the WZ Sge stars.  These stars are
probably not distinct in any deep way from the SU UMa class, being
essentially the most infrequent erupters in that class.  But the
evidence on this point is still slim; these stars erupt so seldom that
we ought to leap into action when the opportunity for study finally
arrives.

So set the VCR to tape the Olympics, and get thee to a telescope.


Joe Patterson
Dept. of Astronomy, Columbia Univ.