[vsnet-campaign-news 122] Recurrent outburst of IM Nor?

[Taichi Kato <tkato@kusastro.kyoto-u.ac.jp>]

   We have been informed by William Liller (Chile) that the old nova IM Nor
(1920) seems to be undergoing the second historical outburst.  Urgent
observations (astrometry, spectroscopy etc.) are needed.

   Original report follows:

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On a total of five photographs (85mm f/1.4 lens, Tech Pan film, orange
filter) taken between Jan. 10.3432 and Jan 10.3595, a star, apparently the
old nova IM Normae, was found at red magnitude 8.3.  It was subsequently
found at approximate magnitude 8.5 at the very edge of another pair of
photographs taken on Jan. 3.3479 and Jan. 3.3493.  Nothing was visible at
the position of the star on Oct. 13 down to magnitude 11.5.

IM Nor was originally discovered by I.E. Woods at 9th magnitude on a
blue-sensitive plate taken on July 7, 1920.  J.L. Elliot and W. Liller
later suggested that it was an X-ray source (ApJ 175, L69, 1972), and
determined its light curve from old Harvard plates.  No other outbursts
were found.

Note that there has never been any spectroscopic verification.  Because the
star is an early morning object, it is can be followed -- and should be
folllowed -- for much of the year.  Its position is (2000) R.A. 15h 39m
29.9s, Dec. -52d 19' 20".

I will try to get an accurate position and a low-resolution sprectrum
tonight although I see that there is a fog bank on the western horizon.

All the best to all,   Bill Liller

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   We have set up a Web page on IM Nor:

   http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/Novae/imnor.html

Regards,
Taichi Kato
On behalf of the VSNET Collaboration team

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  VSNET (Variable Star Network) is an international variable star observing
network, covering various areas of novae, supernovae, cataclysmic variables
(CVs), X-ray transients, and other classical eruptive, pulsating, and
eclipsing variables.  VSNET is one of invited contributing organizations
to the SkyPub AstroAlert system.

       VSNET Home Page: http://vsnet.kusastro.kyoto-u.ac.jp/vsnet/

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