TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  2337
SUBJECT: IPN triangulation of GRB030725 (=H2779; small error box)
DATE:    03/07/29 21:14:33 GMT
FROM:    Kevin Hurley at UCBerkeley/SSL  <khurley@sunspot.ssl.berkeley.edu>

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

I. Mitrofanov, S. Charyshnikov, V. Grinkov, 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,

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, 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:

Ulysses, Mars Odyssey-GRS, Konus-Wind, RHESSI, INTEGRAL (SPI-ACS), and,
of course, HETE-FREGATE, observed this GRB (H2779, GCN 2322).  Because
Ulysses, Earth, and Mars are practically aligned, a small error box
cannot be derived for this burst by triangulation alone.  However, five
statistically independent annuli can be obtained for it.  Their 3 sigma
widths are 11.2' (Ulysses-Mars Odyssey), 8.0' (Ulysses-Konus), 5.3'
(Ulysses-RHESSI), 4.2' (Ulysses-INTEGRAL), and 4.9' (Ulysses-HETE).
All these annuli are consistent with, and reduce the area of, the HETE
SXC 90% confidence error box given in GCN 2322.  Although the optical
transient reported by Henden (GCN 2324, 2334) lies slightly outside the 90%
confidence SXC error box, it lies within all the IPN annuli, at
distances from the centerlines corresponding to 0.6 sigma (Ulysses-
Mars Odyssey), 2.3 sigma (Ulysses-Konus), 1.6 sigma (Ulysses-RHESSI),
1.6 sigma (Ulysses-INTEGRAL), and 0.7 sigma (Ulysses-HETE FREGATE).

The narrowest 3 sigma annulus (Ulysses-INTEGRAL) intersects the 90%
confidence SXC error box to form an error box whose area is
~16 sq. arcmin., or a factor of ~5 smaller than the SXC error box.
The intersection points are:

	RA(2000)	Decl.(2000)
	308.487		-50.701
	308.486		-50.586
	308.415		-50.527
	308.400		-50.629

A map will be posted shortly at ssl.berkeley.edu/ipn3/030725