[AAVSO-HEN] GRB 070621: UVOT-enhanced XRT position

[grb at aavso.org]

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TITLE:   GCN CIRCULAR
NUMBER:  6567
SUBJECT: GRB 070621: UVOT-enhanced XRT position 
DATE:    07/06/22 08:56:15 GMT
FROM:    Boris Sbarufatti at INAF-IASF-Pa  <sbarufatti at ifc.inaf.it>

B. Sbarufatti (INAF-IASF Pa),  P. A. Evans (LU) report  on behalf of  
the Swift team

Using 746 s of overlapping XRT Photon Counting mode and UVOT V-band
data, we find an astrometrically corrected X-ray position (using the  
XRT-UVOT
alignment and matching UVOT field sources to the USNO-B1 catalogue):  
RA, Dec =
323.79225, -24.81752 which is equivalent to:

RA (J2000):  21 35 10.10
Dec (J2000): -24 49 03.1

with an uncertainty of 2.0 arcsec (90% confidence).