[vsnet-alert 5523] SNe 2001A, 2001B, and 2001C

[Hitoshi YAMAOKA <yamaoka@rc.kyushu-u.ac.jp>]

Dear SN watchers,

  After the opening of the new year (century, millenium), three SNe
discoveries have been reported already.  SN 2001A is nearby but dim.
The other two are fairly bright, so the good targets to follow-up.

  SN 2001A was discovered on Jan. 1.5 UT at mag 18.9 with KAIT, and
confirmed on the a half-month previous image at mag 18.4.  The
position is R.A. = 12h19m23s.01, Decl. = +5o49'40".5 (2000.0), which
is about 3" west and 11" north of the nucleus of the giant elliptical
galaxy NGC 4261.  It is well inside of the large main body of NGC
4261.  

  NGC 4261 is well-studied radio galaxy (3C270) in the Virgo cluster.
It is believed that there is a supermassive blackhole in the core, and
the surrounding disk and polar radio lobe are observed.  On the other
hand, the elliptical galaxies believed to produce SNeIa only, whose
maximum magnitude is about mag 14 at this distance.  So, SN 2001A can
be 1) very old SN Ia (the reference image by KAIT = last negative
observation ? is taken on 2000 May), 2) SN Ia obscured by the dust, 
3) foreground variable or 4) background SN.  The spectroscopy is very
urged.  The photometry would be very difficult because of the glare of
the host galaxy.

  SN 2001B was discovered by Beijing them on Jan 3.61 UT (mag about
15.5) and confirmed on the next day with 0.3 mag brighening.  The
position is R.A. = 4h57m19s.24, Decl. = +78o11'16".5 (2000.0), which
is about 6" west and 9" south of the nucleus of the somewhat
odd-shaped face-on spiral (SA(s)c) galaxy IC 391.  It lies on the
midpoint of the southern diffuse arm.  The recession velocity of the
host galaxy (1556 km/s) suggests that the typical SN Ia without
extinction will be mag about 13.3 at its maximum.  The followup
photometry is very important for this brightening object as well as
the spectroscopic confirmation. 

  SN 2001C was discovered by T. Puckett and his coleague A. Sehgal on
Jan. 4.09 UT at mag 14.7.  The location is R.A. = 6h59m36s.10, Decl. =
+59o31'01".6 (2000.0), which is about 15" east and 6" south of the
center of the tilted spiral (Sb) galaxy PGC 19975.  It is well outside
of the visible disk, and there is a foreground mag 16 (or dimmer?) 
star 8" west and 18" south of the nucleus of PGC 19975.  The recession
velocity of the host galaxy is 3280 km/s, so the expected SN Ia
maximum is about mag 14.8.  The followup observation is recommended
for this bright target.

Sincerely Yours,
Hitoshi Yamaoka, Kyushu Univ., Japan
yamaoka@rc.kyushu-u.ac.jp

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