srclist paragraph message for exposure 1 of trigger 1185505
THIS MESSAGE IS *NOT* READY FOR DISTRIBUTION.
MORE ANALYSIS IS REQUIRED TO DETERMINE WHETHER THERE IS AN AFTERGLOW CANDIDATE.
IMAGE PROBLEM: high density of stars
SRCLIST PROBLEM: high density of stars, srclist filled telemetry buffer
See notes for more details.
WARNING -- because of the LARGE EXTINCTION, results should be used cautiously.
1 source(s) near the XRT position were rejected as afterglow candidate(s). See
notes for details.
------ Start for Possible Stand-alone Circular ----
In response to GRB230815 (Swift/BAT trigger 1185505) at 10:49:55 UT,
---- UVOT paragraph for Joint or Stand-alone Circular ----
UVOT took a finding chart exposure of 250 seconds with the U filter starting
18409 seconds after the BAT trigger. No credible afterglow candidate has been
found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the
XRT error circle. Because of the density of catalogued stars, further analysis
is required to report an upper limit for any afterglow in the sub-image. The
8'x8' region for the list of sources generated on-board covers 100% of the XRT
error circle. Because of the density of catalogued stars, further analysis is
required to report an upper limit for any afterglow in the region. No
correction has been made for the large, but uncertain, extinction expected.
------- notes for trigger 1185505 ------
uvot_gcn_auto.pl vrs. 2023-03-28 fem at 230815d21h56m19s893248usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=1185505
-expid=713807836 -meonly -msg_srclist
Results from standard processing of UVOT TDRSS data for this trigger should be
available at
http://heasarc.gsfc.nasa.gov/docs/swift/uvot_tdrss/1185505/
Links to data for all triggers can be found at
http://heasarc.gsfc.nasa.gov/docs/swift/uvot_tdrss/
Unreliable extinction found for xrt position. XRT position found for srclist.
XRT position found for Genie image. BAT position found.
UVOT exposure began at MET 713807836.81292 or about 2023:227:15:57:11 UT
Since the srclist star catalog filled its buffer, the sensitivity for an
afterglow may be REDUCED. The stars will eliminate afterglows from about 61%
or more of the srclist region. Found 190 sources in srclist catalog. WARNING --
srclist catalog buffer filled. Found 51 srclist source(s) without IDs. There
are 0 good candidate(s) in the srclist catalog. Good candidates must be
brighter than 18.12 mag.
Found 13 source(s) in Genie image catalog. 1 source(s) are within 10.0" of the
xrt position. Found 1 Genie image source(s) without IDs. There are 0 good
candidate(s) in the Genie image catalog. Good candidates must be brighter than
19.97 mag. Found 527 stars in largest star catalog for Genie image region. The
stars will eliminate afterglows from about 59% of the Genie image region.
Genie image analysis:
Found 41553.4 counts in the large background region of 6043.0 pixels or a rate
of 6.876 counts/pixel in a radius of 45.0 arcsec. Based on this background, the
typical 5-sigma UL at a random point in the Genie image is 19.24 mag. for a
4-arcsec aperture.
Found 1439.4 counts in the XRT position region of 200.0 pixels or a rate of
7.197 counts/pixel in a radius of 8.0 arcsec. The net count rate (using local
background region) at the XRT position is 0.298 +/- 0.163 (1-sigma) cps or
19.47 mag and a range from 19.00 to 20.33 mag. The 3-sigma UL at the XRT
position is 0.788 cps or 18.42 mag. The number of srclist sources filled the
available telemetry. The weakest source detected was 18.21 mag. The closest
srclist source has ra= 184.6951 dec= -58.0601 mag=15.66 sep=59.16".
Found 1 Genie source(s) within 10.0" of the XRT position. The brightest such
source has ra= 184.7271 dec= -58.0546 mag=17.69 sep=8.60". The closest Genie
source has ra= 184.7271 dec= -58.0546 mag=17.69 sep=8.60".
Report rejected UVOT sources within 10 arcsec XRT position.
Such sources are usually NOT the afterglow.
****THIS SOURCE NEAR XRT POSITION WAS REJECTED--USE WITH CAUTION****
UVOT took a finding chart exposure of 250 seconds with the U filter starting
18409 seconds after the BAT trigger. There is a candidate afterglow in the
rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 12:18:54.50 = 184.72710
DEC(J2000) = -58:03:16.7 = -58.05463
with a 90%-confidence error radius of about 0.64 arc sec. This position is 8.60
arc sec. from the center of the XRT error circle. The estimated magnitude is
17.69 with a 1-sigma error of about 0.15. No correction has been made for the
large, but uncertain, extinction expected.
All AG candidates sorted by magnitude for the current finding chart.
(U/V/White SRCLIST mags < 17.5/17.5/18.5 are reliable. Mag > 18.5/18.5/19.5 are
not. Others are uncertain.)
(U/V/White Genie image mags < 18.0/18.0/19.0 are reliable. Mag > 19.0/19.0/20.0
are not. Others are uncertain.)
(Magnitudes followed by * have been corrected for exposure.)
---MET--- -dt- filter ---RA-- ---DEC--- -MAG/Limit Dist(") Source Asp.Corr?
713807836 18408 U srclist found no candidates.
713807836 18408 U image found no candidates.
List afterglow candidates for other finding charts.
713789582 154 ? srclist data are not available.
713789582 154 WHITE image found no candidates.
713808092 18664 B srclist found no candidates.
713808092 18664 B image found no candidates.
713811725 22297 B srclist found no candidates.
713811725 22297 B image found no candidates.
713812038 22610 ? srclist data are not available.
713812038 22610 U image found no candidates.
713817179 27751 U srclist found no candidates.
713817179 27751 U image found no candidates.
713817434 28006 B srclist found no candidates.
713817434 28006 B image found no candidates.
713817748 28320 U srclist found no candidates.
713817748 28320 U image found no candidates.
713818003 28575 B srclist found no candidates.
713818003 28575 B image found no candidates.
713828679 39251 U srclist found no candidates.
713828679 39251 U image found no candidates.
713828934 39506 B srclist found no candidates.
713828934 39506 ? image data are not available.
------- Tokens for Quick GCN -------