TITLE:   GCN CIRCULAR
NUMBER:  3442
SUBJECT: XRF050509C: Chandra Afterglow Detection
DATE:    05/05/20 18:09:04 GMT
FROM:    Derek Fox at CIT  <derekfox@astro.caltech.edu>

Derek B. Fox (Caltech) reports on behalf of a larger collaboration:

"We have observed the afterglow (Gorosabel et al, GCN 3425) of XRF
050509C (Prigozhin et al., GCN 3402) with the Chandra X-ray
Observatory and ACIS-S detector, in a single 20-ks pointing beginning
at 09:54 UT on May 19, and detect the X-ray afterglow at a count rate
of 0.7(2) counts per ksec.  This count rate corresponds to a 0.5-10
keV flux of 9E-15 erg cm-2 s-1, assuming a spectrum with power-law
photon index alpha=1.5 and Galactic N_H=5.5E+20 cm-2.  We note that
this flux is consistent with the upper limit from Swift XRT at a
similar epoch (Campana et al., GCN 3441)."