[vsnet-chat 7360] Re: MisV1396 - remarkably blue star with a rare variation

[Seiichi Yoshida]

Dear Arne Henden,

Thank you very much for your comments.

> This star is not remarkably blue as far as I can tell.  For example,
> the TASS patches catalog lists it as V=11.51, (V-Ic) = 0.41.
> Tycho (at its limit) gives V=11.524 (B-V) = 0.275
> 2MASS gives J=10.704, H=10.662, K=10.592
> All of these are consistent with approximately an F0V star.
> 
> Please do not rely on USNO-A or USNO-B photometry.  Among other things,
> 11th magnitude stars are heavily saturated on the Schmidt plates.  I would

I agree that MisV1396 is not remarkably blue as you wrote. I modified
the sentenses in my web pages on this star.

> also not consider this star variable based on a single discrepant datapoint,
> especially since NSVS does not show any variation.  There are *many* ways
> in which a single image can yield a discrepant magnitude.

Well, I konw the only single image is not reliable to see variation,
due to the noises, cosmic rays, CCD pixel problems, sky conditions,
etc., etc... Actually, we do not assign MisV number in general if a
star is bright or faint in only single image. 

But in this case, we investigated the images carefully, and got
confident that the variation is real.

This star will be a long periodic EA type, I guess. So let's wait for
another eclipsing event in the future.

Best regards,

--
Seiichi Yoshida
comet at aerith.net
http://www.aerith.net/