Central Bureau for Astronomical Telegrams
IAUC 7604: P/2001 F1; 2001ah; 2001U
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Circular No. 7604
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
URL http://cfa-www.harvard.edu/iau/cbat.html ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)
COMET P/2001 F1 (NEAT)
E. F. Helin, S. Pravdo, and K. Lawrence, Jet Propulsion
Laboratory, report the discovery of a comet with a faint tail about
40" long toward the west-northwest on CCD images taken with the
NEAT 1.2-m reflector at Haleakala (discovery observation given
below). Additional observations, together with orbital elements (T
= 2001 Jan. 21, q = 4.3 AU, i = 19 deg, P = 15.4 yr) by B. G.
Marsden, are given on MPEC 2001-F51. The object appears diffuse on
Mar. 28.5 UT CCD images taken by G. J. Garradd, Loomberah, N.S.W.
(0.45-m f/5.4 reflector). CCD observations by M. Tichy and M.
Kocer at Klet (0.57-m f/5.2 reflector) on Mar. 29.0 show a diffuse
10" coma. P. G. Comba, Prescott, AZ, reports that CCD images taken
with a 0.46-m f/4.5 reflector on Mar. 29.3 show a tail in p.a. 285
deg.
2001 UT R.A. (2000) Decl. m1
Mar. 24.41577 13 25 41.76 +17 33 44.0 19.7
SUPERNOVA 2001ah IN UGC 6211
T. Matheson, S. Jha, P. Challis, and R. Kirshner, Harvard-
Smithsonian Center for Astrophysics, report that a spectrum of SN
2001ah (cf. IAUC 7603), obtained by P. Berlind on Mar. 28.21 UT
with the F. L. Whipple Observatory 1.5-m telescope (+ FAST
spectrograph), shows it to be a peculiar type-Ia supernova well
before maximum light. The Si II 635.5-nm feature is extremely weak
or absent, but the Fe III lines at 430 and 500 nm are present, just
as in SN 1991T. There is, however, strong Ca II H and K absorption,
implying that SN 2001ah is more like SN 1998ab (cf. IAUC 6858) or
SN 1998es (cf. IAUC 7054). Narrow H-alpha emission from a nearby H
II region indicates a recession velocity of 16 800 km/s for the
host galaxy. The expansion velocity derived from the minimum of
the Ca II line (rest 395.1 nm) is about 20 400 km/s.
SUPERNOVA 2001U IN NGC 5442
A. V. Filippenko, University of California, Berkeley; and A.
J. Barth, Harvard-Smithsonian Center for Astrophysics, report that
inspection of a CCD spectrum (range 430-680 nm), obtained on Mar.
29 UT with the Keck-I telescope, reveals that SN 2001U (IAUC 7583)
is of type Ia, roughly 2 months past maximum brightness.
(C) Copyright 2001 CBAT
2001 March 29 (7604) Daniel W. E. Green
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