[vsnet-chat 4362] re V1436 Aql & suspect variables

[crawl@zoom.co.uk]

Hey, don't let me put anybody off following this thing with pep!

It is of course part of human nature to be more interested in following a
star to define its variability than it is to follow a suspected variable
with the idea of proving it to be constant, though in purist terms I
suppose both activities should be equally valid.

Oh, and Stan Walker has kindly reminded me about BY Dra stars, which can
include stars of spectral type dMe, although I think V1436 Aql and V0374
And are only dM, with no 'e', just cos they don't eclipse doesn't mean they
are constant.  Granted Chris Lloyd can't find a period in the Tycho epoch
photometry.  On the other hand, Hipparcos documentation states that epoch
photometry from either experiment is blind to periods between 20 and 100
days due to the sampling regime of the observations, and Chris probably
wouldn't have been looking in these period ranges anyway.  BY Dra stars can
have periods falling within this range.  Don't know enough about this
variability type to comment one way or the other though, just pointing it
out.  Personally I'm tempted to go along with Chris' comments re the epoch
photometry.


Incidentally, I've often wondered how many observers add a [non-CV] suspect
variable or two to their lists.  Okay, so many of the MISAO, Tmz and what
have you variables are LPVs, which ain't that fashionable nowadays, but
you'd think it'd be of interest to be the first person to plot and define a
variable's behaviour, as a long term project.  Of course, if it is a CV
suspect, you may the the first to catch it in outburst since the discovery
plate decades ago, and it is easy enough to just keep checking that field
for an outburst, when compared to the greater effort involved following an
LPV.

I know I never used to follow any of those suspects when I was able to
observe, but that may be more to do with the fact that I didn't know
anything about them then!  Besides which, I found the hard way that I
couldn't estimate red variables for toffee, despite full colour vision
[which don't help the rods anyway ;)] - I tried it on R Leonis and we just
didn't get on, so I stuck to CVs.

Anyway, a lot of these suspect stars are LPVs and one or two added to
someone's list may add a bit of interest to things, watching the behaviour
of this star develop over the years.  Maybe the limited venues for
publication of visual data so derived puts folk off, but then few folk are
that bothered about publishing.

Just a thunk...

Cheers

John

JG, UK

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