TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  1388
SUBJECT: GRB020405 field photometry at ESO
DATE:    02/05/10 16:25:52 GMT
FROM:    Nicola Masetti at ITeSRE,CNR,Bologna  <masetti@tesre.bo.cnr.it>

A. Simoncelli, E. Maiorano (U. Bologna), E. Palazzi, N. Masetti
(IASF/CNR, Bologna), E. Pian (INAF, OA Trieste), J. Hjorth (U.
Copenhagen), A. Castro-Tirado (IAA-CSIC, Granada), A. Fruchter
(STScI, Baltimore), J. Greiner (MPE Garching and AI Potsdam), L.
Kaper, E. van den Heuvel (U. Amsterdam), A. Delsanti, M. Billeres
(ESO), on behalf of the GRACE Collaboration, report:

"We have acquired BVRcIc photometry of the field of GRB020405 with the
Danish 1.54m and NTT 3.58m ESO telescopes at La Silla, Chile. 

We placed the photometric data of 6 selected stars, together with an
R-band image of the field on which the stars are marked, at the URL: 

http://tonno.tesre.bo.cnr.it/~masetti/grb020405_phot.html 

The current photometry has a potential external zero-point error of about
three percent that needs to be added in quadrature to the Poisson errors
given for the magnitude uncertainties of the selected stars.

Specifically, the magnitudes of the USNO-A2.0 stars 0525-16813005 and
0525-16815468 (Palazzi et al., GCN #1328; Hjorth et al., GCN # 1329),
which are labeled as stars # 2 and # 5 of our sample, are 
V = 19.01 +- 0.01, R = 18.48 +- 0.01 for the first one and 
V = 17.92 +- 0.01 for the second.". 

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