[vsnet-campaign-dn 1309] WZ Sge companion

[aah@nofs.navy.mil]

For those interested, here are the UBVRI magnitudes
for the companion (zero points from the Henden/Sumner sequence,
which in turn was from only one photometric night, so
the zero points on these can move a couple of hundredths):

  V     B-V    U-B    V-R    R-I
13.884  1.526  1.592  0.776  0.692

photometric error is also about 0.02mag for each magnitude/color
except for U-B, which has a 0.06mag error.  I'll adjust
these values in a few days when I get more photometric data
on the field.

The companion is about 7arcsec west of the variable, so if
you are using apertures larger than about 15arcsec diameter,
you will be including the much of the companion in the aperture.
For unfiltered or reddish filters, the companion currently
contributes about half of the light in apertures that include
both stars.  For apertures smaller than 15arcsec, you will be
just measuring the variable.  It is those apertures near 15arcsec
that will have the most problem, as you may or may not include
the companion depending on the seeing and the quality of your
centroiding when two equal-magnitude stars are near each other.
Arne

VSNET Home Page

---

vsnet-adm@kusastro.kyoto-u.ac.jp

VSNET Home Page

Return to Daisaku Nogami

---

vsnet-adm@kusastro.kyoto-u.ac.jp