Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 17303

Swift detection of the variable star SZ Psc
2015-01-15T09:36:31Z (9 years ago)
Kim Page at U.of Leicester <>
V. D'Elia (ASDC), M. De Pasquale (INAF-IASFPA),
P. A. Evans (U Leicester), H. A. Krimm (CRESST/GSFC/USRA),
A. Maselli (INAF-IASFPA), K. L. Page (U Leicester), T. Sakamoto (AGU)
and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:

At 09:08:42 UT, the Swift Burst Alert Telescope (BAT) triggered and
located a source (trigger=625898).  Swift slewed immediately to this location. 
The BAT on-board calculated location is 
RA, Dec 348.364, +2.679 which is 
   RA(J2000) = 23h 13m 27s
   Dec(J2000) = +02d 40' 45"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  This is a 320-s image trigger. 
As is usual with an image trigger, the
rapidly available BAT light curve shows no significant features. 

The XRT began observing the field at 09:15:03.4 UT, 380.5 seconds after
the BAT trigger. XRT found a bright X-ray source located at RA, Dec
348.3493, 2.6753 which is equivalent to:
   RA(J2000)  = +23h 13m 23.83s
   Dec(J2000) = +02d 40' 31.1"
with an uncertainty of 4.9 arcseconds (radius, 90% containment). This
location is 54 arcseconds from the BAT onboard position, within the BAT
error circle. This position is 4.1 arcseconds from that of a known
X-ray source: XMMSL1 J231323.5+024033 in the XMM-NEWTON XMMSLEWCLN
catalogue, also known as SZ Psc, a RS CVn variable type. No event
data are yet available to determine the column density using
X-ray spectroscopy. 

The initial flux in the 2.5 s image was 3.72e-09 erg cm^-2 s^-1 (0.2-10

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 389 seconds after the BAT trigger. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The source appears saturated. 
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
Looking for U.S. government information and services? Visit