[vsnet-chat 7327] Complex around a Mira type variable MisV1262

[Seiichi Yoshida]

Dear colleagues,

MisV1262, R.A. = 22h24m06s.65, Decl. = +54o45'33".4 (2000.0), is one
of the new variable stars discovered by the MISAO Project.

It was announced on 2004 Mar. 18 as a possible semi-regular variable
with an unfiltered magnitude range of 12.5 - 13.8 based on our
observations between 2000 Aug. 29 and 2001 Oct. 13 by Nobuo Ohkura.

Further observations in 2003 September by Nobuo Ohkura revealed that
the amplitude is much larger, with an unfiltered magnitude range of
12.5 - 14.5, and it is probably a Mira type.

Unexpectedly, V-band observations around the same time by Nobuo Ohkura
also caught a 14.9 mag star at the position of MisV1262. It was almost
constant at 14.9 mag between Oct. 25 and Nov. 4 in 2003, and between
Oct. 15 and Nov. 1 in 2004.

Investigating DSS images and USNO-B1.0 catalog, I found there is a
complex of three stars within 15 arcsec at the position of MisV1262.

  (1) USNO-B1.0 1447-0404771  22h24m06s.1207 +54o45'25".570
        17.150(B1)  15.600(R1)  17.650(B2)  16.490(R2)

  (2) USNO-B1.0 1447-0404778  22h24m06s.5313 +54o45'32".900
        16.880(B1)  17.540(B2)
    = USNO-B1.0 1447-0404781  22h24m06s.6493 +54o45'33".350
        12.180(R1)  14.060(R2)

  (3) USNO-B1.0 1447-0404786  22h24m07s.1247 +54o45'38".210
        15.020(B1)  15.440(B2)  14.660(R2)

It is clear that star (2) is our variable star MisV1262 based on the
DSS images and USNO-B1.0 color. 

The DSS images and USNO-B1.0 color revealed that star (3) becomes
brighter than star (2) in B-band, and probably in V-band. Therefore,
a 14.9 mag star in our V-band images in 2003 and 2004 must be star
(3), not MisV1262. MisV1262 must have been much fainter at that time.

The NSVS light curve also shows a rough variation of this star with a
range of 12.8 - 14.1 mag. However, the NSVS data must be blending of
the complex, and must not show the total variation.

Images, light curves and further information are available at:

  http://www.aerith.net/misao/data/misv.cgi?1262

  http://www.aerith.net/misao/report/variable/MisV1262.html

Best regards,

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