TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  1374
SUBJECT: GRB020410: BeppoSAX NFI observations refined analysis
DATE:    02/04/18 11:05:44 GMT
FROM:    Luciano Nicastro at IFCAI-CNR  <nicastro@ifcai.pa.cnr.it>

L. Nicastro, Istituto di Astrofisica Spaziale e Fisica Cosmica (IASF-CNR),
Palermo; L. Piro, G. Gandolfi, M. Feroci, (IASF-CNR), Rome;
M. Capalbi, M. Perri, ASI Science Data Center, Rome;
J. Heise, J. in't Zand, Space Research Organization Netherlands, Utrecht,
report:

"BeppoSAX performed two NFI observations of the candidate GRB 020410.
Start times were Apr. 11, 06:53 UT (20.2 hrs after the burst) and
Apr. 12 16:49 UT (54.3 hrs after the burst). We detect a single
unknown slowly fading source in both observations whose refined
coordinates (J2000) are:

 RA: 22 06 25.8, Dec: -83 49 27

This is 1.3 arcmin from the WFC derived position (GCN 1349) and 15 arcsec
from the quick-look analysis derived one (GCN 1366).
The error circle radius is 20 arcsec (90% confidence).
This is the smallest ever reported for a BSAX-NFI detected GRB.
For more information about NFI source coordinates accuracy see the
BeppoSAX-ASDC report at the URL:
  http://www.asdc.asi.it/bepposax/coord_correction.html

Images of the two observations and the decay behavior are posted at the URL:
  http://www.ifcai.pa.cnr.it/~nicastro/saxtoo-grb020410

We note that no gamma-ray detection was reported so far (the BSAX-GRBM
was not operative). This fact, the X-ray properties of the WFC (2-28 keV)
prompt event and the spectral/temporal behavior of the afterglow
strongly support the hypothesis of a XRF or anomalous GRB.

(Sub-)arcsec position accuracies obtainable with Chandra or XMM-Newton
would greatly facilitate deeper studies at other wavelengths."

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