TITLE:   GCN CIRCULAR
NUMBER:  21787
SUBJECT: LIGO/Virgo G298048: Chandra monitoring of the X-ray emission from SSS17a
DATE:    17/09/02 17:06:21 GMT
FROM:    Eleonora Troja at GSFC/Swift  <nora.gsfc@gmail.com>

E. Troja (UMD/GSFC), L. Piro (INAF/IAPS), T. Sakamoto (AGU),
S. B. Cenko (NASA/GSFC), and A. Lien (UMBC/GSFC) report on behalf
of a larger collaboration:

We re-observed the field of SSS17a (Coulter et al., LVC GCN 21529) with
the Chandra X-ray Observatory (PI: E. Troja) on 2017-09-01
(~15 days after the LVC trigger) for a total exposure of 47 ks.

The X-ray source reported in Troja et al. (LVC GCN 21765) is still
detected.
At the position of the optical/IR transient we measure ~17 net counts.
By describing the spectrum with an absorbed power-law we estimate a flux
of approximately 4.5E-15 erg/cm2/s (0.5-8.0 keV).

We thank Belinda Wilkes and the entire Chandra team for approving and
scheduling these observations.