[vsnet-chat 633] New CVs from FBS objects

[Taichi Kato <tkato>]

   Abrahamian and Mickaelian 1996 (Astrophysics 39, 315) reports their
spectroscopic detection of six CVs from the FBS (First Byrakan Spectral
Sky Survey).  For those interested in CVs monitoring:

                     (1950.0)          V   type
  FBS0657+888   06 57 24  +88 50.6   15.0   CV
  FBS1328+881   13 28 52  +88 03.5   16.2   CV
  FBS1330+837   13 30 04  +83 41.8   14.9   CV:
  FBS1441+827   14 41 27  +82 42.7   15.6   CV:
  FBS1719+834   17 19 54  +83 21.9   13.5   CV (nova?)
  FBS1735+825   17 35 22  +82 28.8   14     CV (nova or dwarf nova?)

   According to their remarks, FBS1719+834 was detected on the plate
taken on 1976 June 25/26.  The object showed emission lines, which they
interpreted as Hgamma+[O III]4363 and [N III]3869+3968 or Ca H and K.
From the non-appearance on the plate on 1974 May 25/26, and on the POSS,
they concluded this object may be a nova caught in the nebular stage.
The amplitude is no less than 7.5 mag.

   FBS1735+825 was detected (the date not given) as an object with a
featureless spectrum (note the low dispersion).  There is no POSS counterpart,
thus giving an amplitude of larger than 7 mag.  They suspected this object
to be a nova or nova-like.

   I suspect the latter may well be a large-amplitude dwarf nova, caught
during an outburst.  The "nova" classification of the first object largely
depends on the line identifications.  If there were actually only Hgamma
and Ca H and K, this star might also be a dwarf nova in decline from outburst.
This object is close to the Mira-type star Y UMi.  Did anyone look at this
field near the epoch of discovery?  If this is indeed a nova, the object
may have attained a much brighter magnitude at this high galactic lattitude
(think of RW UMi).  Even negative estimates from photographs (even wide-field
ones) near the epoch of the discovery would be worth studying.

   Anyway, wouldn't it be worth monitoring these two objects?  (Unfortunately,
I don't have an access to the identification charts.  The authors stated the
accuracy of the coordinates is about 0'.1, probably enough for visual or CCD
monitoring for possible future outbursts).

Regards,
Taichi Kato

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