[vsnet-grb-info 19971] GROND observations of GRB 171027A: correction

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22058
SUBJECT: GROND observations of GRB 171027A: correction
DATE:    17/10/27 11:49:56 GMT
FROM:    Patricia Schady at MPE/Swift  <pschady at mpe.mpg.de>

P. Schady (MPE) reports:

The upper limits reported in GCN #22056 were in fact calibrated against
GROND zeropoints. The 3-sigma upper limits (AB) calibrated against
PanSTARRS are in fact:

g' > 22.2
r' > 22.2
i' > 21.2
z' > 21.0

The reported magnitudes are not corrected for the expected Galactic
foreground extinction corresponding to a reddening of E_(B-V)=0.12 mag in
the direction of the burst (Schlafly & Finkbeiner 2011).