GCN Circular 1939

K. Hurley and T. Cline, on behalf of the Ulysses, HETE, Mars Odyssey,
and KONUS GRB teams,

E. Mazets and S. Golenetskii, on behalf of the Konus-Wind GRB team,

D. M. Smith, R. P. Lin, J. McTiernan, R. Schwartz, C. Wigger, W.
Hajdas, and A. Zehnder, on behalf of the RHESSI GRB team,

A. von Kienlin, G. Lichti, and A. Rau, on behalf of the
INTEGRAL SPI-ACS GRB team,

I. Mitrofanov, D. Anfimov, A. Kozyrev, M. Litvak and A. Sanin, on
behalf of the HEND-Odyssey GRB team,

W. Boynton, C. Fellows, K. Harshman, C. Shinohara and R. Starr, on
behalf of the GRS-Odyssey GRB team, and

G. Ricker, J-L Atteia, N. Kawai, D. Lamb, S. Woosley, J. Doty, R.
Vanderspek, J. Villasenor, G. Crew, G. Monnelly, N. Butler, J.G.
Jernigan, A. Levine, F. Martel, E. Morgan, G. Prigozhin, J. Braga, R.
Manchanda, G.  Pizzichini, Y. Shirasaki, C. Graziani, M. Matsuoka, T.
Tamagawa, K. Torii, T. Sakamoto, A. Yoshida, E. Fenimore, M. Galassi,
T. Tavenner, T.  Donaghy, M. Boer, J-F Olive, and J-P Dezalay, on
behalf of the HETE GRB team, report:

We have searched the IPN data for a gamma-ray burst that might be
associated with SN2003L (Boles, IAUC 8048; Valenti et al., IAUC 8057;
Kulkarni et al., IAUC 8061; Kulkarni & Fox, IAUC 8073).  It has been
suggested by Soderberg et al. (GCN 1834
Not found
 
 
) that SN2003L is actually a
hypernova, and might therefore be similar to SN1998bw/GRB980425.  We
have limited our search to data obtained between November 10 2002 and
January 10 2003.  The missions and experiments in the IPN were Ulysses,
Konus-Wind, RHESSI, Mars Odyssey (HEND and GRS), HETE-2 (FREGATE), and
INTEGRAL (SPI-ACS).  The data on 41 bursts and candidate (unconfirmed)
bursts were examined.  During that period, no burst which could be
localized by the IPN was found to have a source position in any way
consistent with that of the supernova.  That is, there was no event
observed by two or more spacecraft that produced a source annulus or
error box consistent with the supernova.  Several events were observed
each by single spacecraft in the network during this time.  Most of
them can be ruled out as counterparts because of the coarse
localization capabilities of the experiments involved.  However, two such
events had positions which were not inconsistent with the position of
SN2003L.  One occurred on 021213 at 41739 s, and was detected only by
HETE-FREGATE.  Based on Earth-blocking considerations, the probability
of a chance association with SN2003L is ~70%.  This burst had a fluence
of roughly 10^-6 erg/cm^2.  The other occurred on 021228 at 53801 s and
was detected only by Konus-Wind.  Based on the ecliptic latitude
response of the Konus detectors, the probability of a chance
association is ~17%.  This burst had a fluence of ~2x10^-6 erg/cm^2.

Lacking any definite evidence for an association, we can give
an  upper limit to the fluence of a GRB from SN2003L. This limit
depends on the duration, spectrum, and arrival time within the search
window, all of which are unknown (see Hurley et al. GCN 1252
Not found
 
 
), but can
be roughly taken to be several times 10^-7 erg/cm^2 in the energy range
above 25 keV.

SN2003L is about 2.6 times more distant than SN1998bw.  Neglecting
beaming and other event-to-event variations, any associated GRB might
be expected to be 7 times less intense, and possibly undetectable by
IPN instruments.