[AAVSO-HEN] GRB 091020: Late TLS detection

[grb at aavso.org]

The following is a GCN Circular circulated via the AAVSO network.
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TITLE:   GCN CIRCULAR
NUMBER:  10090
SUBJECT: GRB 091020: Late TLS detection
DATE:    09/10/27 02:31:21 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann at tls-tautenburg.de>

D. A. Kann, U. Laux, M. Roeder & H. Meusinger (TLS Tautenburg) report:

We observed again the afterglow of the Swift GRB 091020 (Racusin et al., 
GCN 10048) with the 1.34m Schmidt telescope of the Thueringer 
Landessternwarte Tautenburg, Germany, on the 26th of October, 5.2 days 
after the GRB. We obtained 11 x 600 sec images in Rc before clouds shut us 
down again. At the position of the afterglow, we detect a faint source in 
the stacked image.

We derive the following afterglow magnitudes using the same comparison 
star as Kann et al., GCN 10076:

dt		Filter	mag	dmag
____________________________________
5.213357	Rc	23.62	0.31


Kann et al., GCN 10076, found a single power-law decay with alpha = 1.12 
+/- 0.06. Compared to the extrapolation of this fit, there is no 
significant evidence for a break yet.

No further observations are possible due to an instrument change.

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