Central Bureau for Astronomical Telegrams
IAUC 7740: 2001fb; 1998ff
The following International Astronomical Union Circular may be linked-to from your own Web pages, but must not otherwise be redistributed (see these notes on the conditions under which circulars are made available on our WWW site).
Read IAUC 7741
.dvi or
.ps format.
Circular No. 7740
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)
SUPERNOVA 2001fb IN ANONYMOUS GALAXY
A. Rest, University of Washington, reports the detection of an
apparent supernova (at magnitudes g' = 20.0, r' = 19.0) on Sloan
Digital Sky Survey (SDSS) images taken with the SDSS 2.5-m
reflector on Oct. 10.3 UT. SN 2001fb is located at R.A. =
0h10m06s.15, Decl. = -0 26'18".2 (equinox 2000.0), which is 7".2
west and 8".7 south of the nucleus of the host galaxy. The new
object is not present in SDSS images taken on 1998 Sept. 19.3, to
limiting magnitudes g' = 23 and r' = 22.5. Follow-up observations
taken at the ARC 3.5-m reflector at Apache Point Observatory on
Oct. 24.1 by A. Miceli and R. Covarrubias confirm the existence of
the new object.
SUPERNOVA 1998ff IN ANONYMOUS GALAXY
S. Beckwith, Space Telescope Science Institute, on behalf
of the 'Supernovae at High Z Team' (which includes also A. Riess,
F. Boffi, S. Casertano, R. Doxsey, H. Ferguson, A. Fruchter, M.
Giavalisco, R. Gilliland, I. Griffin, A. Koekemoer, M. Livio, B.
Margon, G. Meylan, N. Panagia, V. Platais, K. Sahu, and D.
Soderblom), reports the discovery of an apparent supernova in the
'Hubble Deep Field South' (HDFS) on WFPC2 images taken with the
Hubble Space Telescope (HST) and filter F814W in Sept. and Oct.
1998: "SN 1998ff was found by differencing the 1998 images with
new HST images taken during 2001 Oct. 2 and 3, also with F814W.
The new object appeared with a starlike point-spread function,
offset 0".08 west of the core of an early-type galaxy (number 2285
from Casertano et al. 2000, A.J. 120, 2747) whose nucleus is
located at R.A. = 22h32m48s.90, Decl. = -60o34'04".8 (equinox
2000.0; uncertainty +/- 0".04). SN 1998ff had a mean magnitude of
[F814W] = 25.3 +/- 0.1 during the HDFS campaign and was seen to
decline by a few tenths of a magnitude during the 12 days of the
campaign. SN 1998ff was independently detected in each of eight
separate, 1-day epochs between 1998 Sept. 28 and Oct. 9. A
photometric redshift of z = 1.20 for the host galaxy was given by
Fontana et al. (2000, A.J. 120, 2206) by employing photometry from
ultraviolet wavelengths through the K band. Low-resolution
spectroscopy of the host galaxy (so as to refine further the
host-galaxy redshift and knowledge of the underlying stellar
population), as well as analysis of deep images of the HDFS taken
in the later half of 1998, may prove valuable."
(C) Copyright 2001 CBAT
2001 October 26 (7740) Daniel W. E. Green
Read IAUC 7741
.dvi or
.ps format.
Our Web policy. Index to the CBAT/MPC/ICQ pages.
