[vsnet-newvar 1812] Some new eclipsing binaries

[Patrick Wils <patrickwils@yahoo.com>]

I have analysed Stardial images (http://vsnet.astro.uiuc.edu/stardial/)
between 1999 and 2002, of a number of regions in the constellation
Monoceros.  To reduce the unfiltered, red sensitive CCD images to
magnitude lists, use was made of programs written by Michael Richmond
(see http://vsnet.tass-survey.org, hereby gratefully acknowledged).  The
data revealed a number of new eclipsing binaries, which are listed
below.

 RA       Dec     ID     Type Ampl   Epoch    Freq c/d  Note
104.575 -4.635  HD 51697  EA   0.2  2452640.75  1.798
105.271 -3.967  HD 52433  EA   0.3  2451586.64  1.339
108.783 -4.745  HD296761  EW   0.7  2452233.88  1.722
114.767 -2.657  BD-2 220  EW   0.4  2452323.65  1.440  BD-2 221?
121.574 -4.447  HD 67093  EA   0.5  2452252.86  0.461

Positions for 2000 are given in decimal degrees.  One Stardial pixel
corresponds to about 0.5', and the positional precision (averages over
more than one hundred images) is on the order of 20".
The identifications were made using Guide software
(http://vsnet.projectpluto.com) and the VizieR utility at the CDS in
Strasbourg (http://vizier.u-strasbg.fr/cgi-bin/VizieR).  Note that the
stars BD-2 220 and BD-2 221 are blended on a Stardial image, therefore
the true identification of the variable is not clear.

The frequency (in cycles/day) is given as a guide only (for EW stars, 2
minima are counted per cycle, for EA stars only one minimum): Stardial
takes images separated by exactly one sidereal day, and the periodogram
is therefore heavily contaminated with aliases.  Any alias of the given
frequency may be the correct one.  One night's observations might
reveal the true period.

Observations are most welcome.

Patrick


__________________________________________________
Do you Yahoo!?
Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
http://mailplus.yahoo.com

VSNET Home Page

Return to Daisaku Nogami

---

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