[vsnet-chat 4794] Re: [vsnet-campaign-dn 1449] WZ Sge companion

[Taichi Kato <tkato>]

Re: [vsnet-campaign-dn 1449] WZ Sge companion

> One further note on the companion.  There was a suggestion
> several emails ago that the companion might be variable.  My
> measures from two nights yielded:
>   V     B-V    U-B    V-R    R-I
> 13.884  1.526  1.592  0.776  0.692
> Krzeminski and Kraft reported measures by Olin Eggen on one
> night with the 5m telescope, yielding:
>   V     B-V    U-B  
> 14.27   1.49   1.45  
> significantly different from my values.  Though this was
> a difficult measurement in the photoelectric days, Eggen's values
> are 0.4mag fainter than my measures, thereby lending credence to
> the variability idea.  As WZ Sge gets fainter, observers might
> consider measuring the companion as well as WZ Sge.

   This "14.3" mag was (at least in the past) canonically used in visual
photometry.  For small telescopes, WZ Sge was difficult to resolve from
the companion visually, and (at least) some people used to report the
combined magnitudes.  Since the combined light was often glimpsed at
significantly brighter than the "14.3" mag companion, there have been a
suggestion that WZ Sge may be undergoing small outbursts (reaching comparable
to "14.3" mag star).  Such a record can be easily found in archival visual
observations.  The present modern photometry seems to have solved this
puzzle!

Regards,
Taichi Kato

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