GCN Circular 315
Subject
GRB990510
Date
1999-05-11T12:56:04Z (25 years ago)
From
Brian Schmidt at Australian Nat. U. <brian@mso.anu.edu.au>
Tim Axelrod, Jeremy Mould, and Brian Schmidt (Research School of Astronomy
and Astrophysics, The Australian National University) report the following
optical photometry of GRB990510 using
the Mount Stromlo 50inch + Macho Camera (measured with respect to the USNO
star at RA = 13:38:00.82, DEC=-80:29:11.7 for which we have assumed
R = 17.2, cf. Galama et al GCN 313). The following observations are Macho R
(effective lambda = 700nm), but transform almost identically to R_c.
R mag err May (UT) Telescope
18.24 0.02 10.514 MSO 50inch
18.31 0.02 10.522 MSO 50inch
18.30 0.02 10.529 MSO 50inch
19.23 0.07 10.775 MSO 50inch
19.31 0.07 10.783 MSO 50inch
19.25 0.04 10.791 MSO 50inch
The absolute uncertainty in the calibration is not included. The decay
is consistent with a power law, with temporal decay index -0.88 +- 0.03.
Simultaneous observations in Macho-B (effective lambda = 510nm)
show a powerlaw decay of index -0.94 +- 0.04.
This message is citeable.
[GCN OP NOTE: This circular was received at 20:26 11 May 99 UT,
but was delayed in distribution due to not having a prior vetting account.]