TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  312
SUBJECT: Galactic extinction towards GRB 990510
DATE:    99/05/10 22:21:11 GMT
FROM:    Krzysztof Z. Stanek at CfA  <kstanek@cfa.harvard.edu>

K. Z. Stanek (Harvard-Smithsonian CfA) notices:

The proposed optical counterpart to GRB990510 (Vreeswijk et al., GCN
#310) lies at the Galactic coordinates of l=305.1175, b=-18.0990.
According to the all-sky reddening map of Schlegel et al. (1998; ApJ,
500, 525), at this position the expected E(B-V) reddening due to the
Galactic foreground is E(B-V)=0.227, i.e. rather considerable. This
corresponds to expected values of Galactic extinction A_U=1.13,
A_B=0.98, A_V=0.74, A_R=0.60 and A_I=0.44, for the Landolt CTIO
filters and standard reddening curve. This might influence planned
optical follow-up of GRB990510.

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