srclist overlap message for exposure 1 of trigger 1069551
uvot_overlap.pl vrs. 2010-12-20b fem started at 210821d02h31m45s695983usUT
The observation of trigger 1069551 started 2021-08-20T17:40:38.9
Examining file ./1069551_g157_uvot_sky_srclist.fits
The exposure ID is 651174038
The exposure time is undefined.
The filter is U.
The uvot region is centered at (20.6351,4.6353) with a roll angle of 70.9
It is square with sides of 12.05 arc min. for an area of 145.15 sq arc min
The BAT error circle is centered at (20.6290,4.6320) with a radius of 3.000 arc min
This is 0.415 arc min from the center of the uvot region
The area of the BAT error circle is 28.27 sq. arc min
The UVOT/BAT overlap is 28.27 sq. arc min or 1.00 of the BAT error circle
The XRT error circle is centered at (20.6396,4.6076) with a radius of 0.042 arc min
This is 1.680 arc min from the center of the uvot region
The area of the XRT error circle is 0.005 sq. arc min
The UVOT/XRT overlap is 0.005 sq. arc min or 1.00 of the XRT error circle
srclist afterglow message for exposure 1 of trigger 1069551
find_uvot_ag.pl vrs. 2020-10-30 fem started at 210821d02h31m48s759886usUT
Observation start time is 2021-08-20T17:40:38.9
Examining file ./1069551_g157_uvot_catalog_srclist.fits
The exposure ID is 651174038
The exposure is 249.924 sec.
The bin size is 2 pixels
The filter is U
There are 34 detected source(s) for 1069551_g157
Aspect correction adds 0.00045 degrees (0.109 sec of time = 1.62 arc sec) to RA
Aspect correction adds -0.00004 degrees (-0.14 arcsec) to Dec
Total aspect correction is 1.63 arcsec
Star catalogs centered at 20.6360 , 4.6254 with radius 8.98 arc min.
n_usno: 531 n_gsc: 0
*** WARNING -- bright star catalog has 2 entries brighter than 12 mag
The brightest has mag 6.92378
RA DEC Mag Color
bright star 0: 20.68111 (01:22:43.47) 4.73824 (+04:44:17.6) 6.92 USNO-V
bright star 1: 20.62796 (01:22:30.71) 4.76269 (+04:45:45.7) 11.88 USNO-V
Mean distance difference (CAT_DELTA) for 20 matched entries is 0.743" for 1069551_g157
Mean and std. dev of mag. difference (MAG_DELTA) are 2.138 and 0.695 for 1069551_g157
Found 14 entries without IDs and 4 entries that are acceptable afterglow candidates for 1069551_g157.
Acceptable entries have no ID, XRT distances < 6.25", and are > 0.8*(80 - 10*(mag-6))" from any bright star
from any bright star and >21.6" from other rejected sources.
2 sources matched bright stars.
Magnitude criteria will be applied later.
BAT distances are from RA=20.6290 (01:22:30.96) DEC= 4.6320 (+04:37:55.2)
XRT distances are from RA=20.6396 (01:22:33.51) DEC= 4.6076 (+04:36:27.5)
*** WARNING 41 per cent of entries have no IDs.
-----------------
Entry 0 in the list of sources is a candidate afterglow for 1069551_g157 with 5x5 stamp
ra=20.63959 (01:22:33.50) dec=4.60783 (+04:36:28.2) +/- 1.1" mag=18.10+/-0.35
dist=0.7 REFID=12
src: 0 distr. of nearby unmatched sources: 0 0 0 0 0
Found 0 entries in star catalog(s) within 20.0" of the candidate.
printing all entries
(Entries within 2 arc sec of a source list entry are considered a match)
##### This source remains a candidate #####
It has no entries within 4" or brighter than 13 mag
-----------------
Entry 3 in the list of sources is a candidate afterglow for 1069551_g157 with 5x5 stamp
ra=20.66566 (01:22:39.76) dec=4.63276 (+04:37:57.9) +/- 1.1" mag=19.12+/-0.35
dist=130.0 REFID=22
*** The position of this source is inconsistent with the XRT position.
The position is 131.6 arc sec from the BAT position.
src: 3 distr. of nearby unmatched sources: 0 0 0 0 0
Found 1 entries in star catalog(s) within 20.0" of the candidate.
RA Dec Sep. Match USNO/ USNO-B USNO-R USNO-V
GSC GSC-F GSC-J GSC-V
20.6658 4.6338 4.0 -1 USNO-B1 14.41 12.99 13.62 *
Due to star catalog entries marked with *, this is probably NOT the afterglow
These entries are within 4" or brighter than 13 mag
-----------------
Entry 5 in the list of sources is a candidate afterglow for 1069551_g157 with 5x5 stamp
ra=20.63896 (01:22:33.35) dec=4.66154 (+04:39:41.6) +/- 1.1" mag=17.37+/-0.35
dist=194.1 REFID=9
*** The position of this source is inconsistent with the XRT position.
The position is 112.2 arc sec from the BAT position.
src: 5 srclist_match has ID
src: 5 distr. of nearby unmatched sources: 1 0 0 1 0
Found 3 entries in star catalog(s) within 20.0" of the candidate.
RA Dec Sep. Match USNO/ USNO-B USNO-R USNO-V
GSC GSC-F GSC-J GSC-V
20.6437 4.6591 19.1 -1 USNO-B1 17.26 15.45 16.25
20.6394 4.6617 1.8 -1 USNO-B1 15.83 13.93 14.77 *
20.6410 4.6647 13.3 -1 USNO-B1 21.30 19.66 20.39
Due to star catalog entries marked with *, this is probably NOT the afterglow
These entries are within 4" or brighter than 13 mag
-----------------
Entry 8 in the list of sources is a candidate afterglow for 1069551_g157 with 5x5 stamp
ra=20.66486 (01:22:39.57) dec=4.67273 (+04:40:21.8) +/- 1.1" mag=20.12+/-0.35
dist=251.2 REFID=34
*** The position of this source is inconsistent with the XRT position.
The position is 195.1 arc sec from the BAT position.
src: 8 distr. of nearby unmatched sources: 0 0 0 0 0
Found 1 entries in star catalog(s) within 20.0" of the candidate.
RA Dec Sep. Match USNO/ USNO-B USNO-R USNO-V
GSC GSC-F GSC-J GSC-V
20.6603 4.6704 18.3 -1 USNO-B1 21.28 99.99 99.99
*** If XRT position is correct, then this is NOT the afterglow
Found 0 entries in star catalog(s) within 10" of the XRT position.
List UVOT sources within 10" of the XRT position:
Unmatched source ra=20.63959 (01:22:33.50) dec=4.60783 (+04:36:28.2) +/- 1.1" mag=18.10+/-0.35 dist=0.7 REFID=12
Good candidates have no ID, acceptable profiles,
mag between 9.01 and 18.12, XRT distances < 6.25",
are > ~(80 - 10*(mag-6))" from any bright star, and have had duplicates removed.
SUMMARY: 1 good candidate(s) found.
srclist paragraph message for exposure 1 of trigger 1069551
------ Start for Possible Stand-alone Circular ----
In response to GRB210820 (Swift/BAT trigger 1069551) at 17:38:00 UT,
---- UVOT paragraph for Joint or Stand-alone Circular ----
UVOT took a finding chart exposure of 250 seconds with the U filter starting
130 seconds after the BAT trigger. There is a candidate afterglow in the
rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 01:22:33.48 = 20.63952
DEC(J2000) = +04:36:28.2 = 4.60783
with a 90%-confidence error radius of about 0.76 arc sec. This position is 0.8
arc sec. from the center of the XRT error circle. The estimated magnitude is
17.53 with a 1-sigma error of about 0.15. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.030.
------- notes for trigger 1069551 ------
uvot_gcn_auto.pl vrs. 2020-10-27 fem at 210821d02h31m53s410476usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=1069551
-expid=651174038 -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/1069551/
Links to data for all triggers can be found at
http://heasarc.gsfc.nasa.gov/docs/swift/uvot_tdrss/
XRT position found for srclist. XRT position found for Genie image. BAT
position found.
UVOT exposure began at MET 651174038.9456 or about 2021:232:17:40:33 UT
Found 527 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 4% of the srclist region. Found 34 sources in
srclist catalog. Found 14 srclist source(s) without IDs. There are 1 good
candidate(s) in the srclist catalog. Good candidates must be brighter than
18.12 mag.
Found 10 source(s) in Genie image catalog. 1 source(s) are within 10.0" of the
xrt position. Found 9 Genie image source(s) without IDs. There are 1 good
candidate(s) in the Genie image catalog. Good candidates must be brighter than
20.48 mag. Found 44 stars in largest star catalog for Genie image region. The
stars will eliminate afterglows from about 4% of the Genie image region. The
Genie image is INCOMPLETE with 3219 null pixels.
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?
651174038 129 U 20.63959 4.60783 18.10/18.1 0.7 srclist Yes
651174038 129 U 20.63952 4.60783 17.53/20.5 0.8 image Yes
List afterglow candidates for other finding charts.
651174769 860 U srclist found no candidates.
651174769 860 U 20.63946 4.60769 18.54/20.2 1.0 image Yes
------- Tokens for Quick GCN -------
CATALOG_TYPE: IMAGE
FILTER: u
GRB_DEC: 4.60783
GRB_ERROR: 0.76
GRB_RA: 20.63952
IMAGE_START_TIME: 17:40:33
MAGNITUDE: 17.53
MAG_ERROR: 0.15
MESSAGE_TYPE: ACK
SOURCE: XRT