GCN Circular 5992

Vanessa Mangano, Boris Sbarufatti, Teresa Mineo (INAF-IASFPA)
report on behalf of the Swift XRT team:


We analysed the first seven orbits of XRT data of GRB070103
(Sakamoto et al., GCN 5988
Not found
 
 
) consisting of 12 ks of exposure
in Photon Counting (PC) mode in the time interval form 100 s
to 30 ks from the trigger.

The refined position of the source is

     RA  (2000) =  23h 30m 13.90s  
     Dec (2000) = +26d 52' 34.17"

with an uncertainty of 3.7 arcsec (90% containment).
This is 4.1 arcsec from the preliminary XRT position and
3.44 arcmin form the refined BAT position
(Barbier et al., GCN 5991
Not found
 
 
).

The 0.3-10 keV X-ray light curve shows an initial flare
peaking at about 500 s from the trigger, followed (after
the first orbital gap) by a power law decay with slope
-1.4 +/- 0.1 up to 30 ks.
If decaying at the present rate the source will reach
a count rate level of 1.5e-3 counts/s
(corresponding to flux level of 1.e-13 erg cm^-2 s^-1)
at T+24 hr.
 
The PC spectrum is well fit by an absorbed power law
with photon index 2.3 +/- 0.1 and N_H (3.2 +/- 0.7) e21 cm^-2
in excess with respect to the Galactic value of 5.0e20 cm^-2.
The average 0.3-10 keV unabsorbed flux during the observation
is 3.8e-12 erg cm^-2 s^-1.

This circular is an official product of the Swift XRT team.