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OT And - var-type:EA
This is a long-period ecclipsing binary with a period of 20.852906 [d].
Further info according to the literature: 7.35-7.95 mag. / spectrum: A3V+A3V.
According to the Cracow database on eclipsing binaries only 7 minima are reported on this variable star (5 primray and 2 secondary) incluing 1999 (http://www.as.ap.krakow.pl/o-c/data/getdata.php3?OT%20and#refs).
The change of brightness in the minimum is very slow and not so easy to measure. On the other hand the variable is sufficiently bright and quite close to a good reference star (GSC3225.2844 / V=8.52 mag.) for good measurement precision. For the first result I was able to measure with a precison of only 5 milli-mag; the second result was a little bit worse, but still ok for an exact determination of the time of minimum light (precision: 8 milli-mag).
Literature: Crawford et al., IBVS 2624
These are my available observation results:
- Result 1 (a primary minimum): And_OT_51425_HSR
- Result 2 (a secondary minimum): And_OT_51853_HSR
- Publication of result 1 in BAV Rundbrief 1999-4, S. 185
KNOWLEDGEMENT FOR DATA REFERENCE:
If results/data from this webpage are used as reference material, the following acknowledgement (or a similar one) is requested:
"We acknowledge the results/data obtained from the Dieter Husar Astronomical Online Database (www.dieter.husar.org)"