image overlap message for exposure 3 of trigger 997453
uvot_overlap.pl vrs. 2010-12-20b fem started at 200926d04h11m06s940573usUT
The observation of trigger 997453 started 2020-09-25T22:05:34.2
Examining file ./997453_g896_uvot_sky_image.fits
The exposure ID is 622764334
The exposure time is 149.868 (seconds)
The filter is WHITE.
The uvot region is centered at (246.8275,78.3914) with a roll angle of 244.0
It is square with sides of 2.68 arc min. for an area of 7.17 sq arc min
The BAT error circle is centered at (246.8510,78.3940) with a radius of 3.000 arc min
This is 0.324 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 7.17 sq. arc min or 0.25 of the BAT error circle
The XRT error circle is centered at (246.7852,78.3905) with a radius of 0.030 arc min
This is 0.513 arc min from the center of the uvot region
The area of the XRT error circle is 0.003 sq. arc min
The UVOT/XRT overlap is 0.003 sq. arc min or 1.00 of the XRT error circle
image afterglow message for exposure 3 of trigger 997453
find_uvot_ag.pl vrs. 2017-02-17 fem started at 200926d04h11m52s572095usUT
Observation start time is 2020-09-25T22:05:34.2
Examining file ./997453_g896_uvot_catalog_image.fits
The exposure ID is 622764334
The exposure is 149.868 sec.
The bin size is 2 pixels
The filter is WHITE
There are 7 detected source(s) for 997453_g896
Aspect correction adds -0.00805 degrees (-1.931 sec of time = -5.83 arc sec) to RA
Aspect correction adds 0.00003 degrees ( 0.10 arcsec) to Dec
Total aspect correction is 5.83 arcsec
Star catalogs centered at 246.8537 , 78.3947 with radius 2.11 arc min.
n_usno: 35 n_gsc: 0
Bright star catalog has no entries brighter than 12 mag
Mean distance difference (CAT_DELTA) for 7 matched entries is 0.235" for 997453_g896
Mean and std. dev of mag. difference (MAG_DELTA) are 1.254 and 0.401 for 997453_g896
Found 0 entries without IDs and 0 entries that are acceptable afterglow candidates for 997453_g896.
Acceptable entries have no ID, XRT distances < 5", and are > 0.8*(80 - 10*(mag-6))" from any bright star
from any bright star and >21.6" from other rejected sources.
Magnitude criteria will be applied later.
BAT distances are from RA=246.8510 (16:27:24.24) DEC=78.3940 (+78:23:38.4)
XRT distances are from RA=246.7852 (16:27:08.45) DEC=78.3905 (+78:23:25.9)
Found 2 entries in star catalog(s) within 10" of the XRT position.
RA Dec Sep. Match USNO/ USNO-B USNO-R USNO-V
GSC GSC-F GSC-J GSC-V
246.7954 78.3907 7.4 -1 USNO-B1 16.98 15.36 16.08
246.7951 78.3900 7.4 -1 USNO-B1 99.99 19.05 99.99
The closest star is 7.38" away.
List UVOT sources within 10" of the XRT position:
Matched source ra=246.79531 (16:27:10.87) dec=78.39074 (+78:23:26.7) +/- 0.6" mag=16.88+/-0.14 dist=7.4 REFID=5 flag=0
There are 1.3658727E+05 counts in the bkg source region of 5999.0000 pixels.
Rate in bkg region from 0 to 45 arcsec is 22.768 counts/pixel (5-sig UL in 4" is 19.65 mag) for 997453_g896
There are 5729.5273 counts in the xrt source region of 198.00000 pixels.
Rate in xrt region with 8 arcsec radius is 28.937 counts/pixel for 997453_g896
There are 28443.605 counts in the xrt_bkg source region of 1246.0000 pixels.
Rate in xrt_bkg region from 15 to 25 arcsec is 22.828 counts/pixel (5-sig UL in 4" is 19.65 mag) for 997453_g896
There are no candidates inside BAT error circle, but outside XRT error circle.
Good candidates have no ID, acceptable profiles,
mag between 9.01 and 20.21, XRT distances < 5",
are > ~(80 - 10*(mag-6))" from any bright star, and have had duplicates removed.
SUMMARY: 0 good candidate(s) found.
Region file: 997453_622764334_200926d04h11m52s572095usUT_bkg.region
# Region file format: DS9 version 3.0
global color=red font="helvetica 10 normal" select=1 edit=1 move=1 delete=1 include=1 fixed=0 source
fk5;circle(246.8275,78.3914,45")
fk5;-circle(246.876765215324,78.3894673247244,6")
fk5;-circle(246.831535531903,78.4027488681186,6")
fk5;-circle(246.79530593016,78.3907428069902,6")
Region file: 997453_622764334_200926d04h11m52s572095usUT_xrt.region
# Region file format: DS9 version 3.0
global color=red font="helvetica 10 normal" select=1 edit=1 move=1 delete=1 include=1 fixed=0 source
fk5;circle(246.78521,78.39053,8")
Region file: 997453_622764334_200926d04h11m52s572095usUT_xrt_bkg.region
# Region file format: DS9 version 3.0
global color=red font="helvetica 10 normal" select=1 edit=1 move=1 delete=1 include=1 fixed=0 source
fk5;circle(246.78521,78.39053,25")
fk5;-circle(246.78521,78.39053,15")
image paragraph message for exposure 3 of trigger 997453
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 GRB200925 (Swift/BAT trigger 997453) at 21:50:37 UT,
---- UVOT paragraph for Joint or Stand-alone Circular ----
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 871 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. The typical 3-sigma upper limit has been about 19.6 mag.
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
0.04.
------- notes for trigger 997453 ------
uvot_gcn_auto.pl vrs. 2016-09-07 fem at 200926d04h11m57s515597usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=997453
-expid=622764334 -meonly -msg_image
Results from standard processing of UVOT TDRSS data for this trigger should be
available at
http://heasarc.gsfc.nasa.gov/docs/swift/uvot_tdrss/997453/
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 622764334.20476 or about 2020:269:22:05:29 UT
Found 518 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 5% of the srclist region. Found 129 sources in
srclist catalog. Found 65 srclist source(s) without IDs. There are 0 good
candidate(s) in the srclist catalog. Good candidates must be brighter than
19.22 mag.
Found 7 source(s) in Genie image catalog. 1 source(s) are within 10.0" of the
xrt position. Found 0 Genie image source(s) without IDs. There are 0 good
candidate(s) in the Genie image catalog. Good candidates must be brighter than
20.21 mag. Found 31 stars in largest star catalog for Genie image region. The
stars will eliminate afterglows from about 4% of the Genie image region.
Genie image analysis:
Found 136587.3 counts in the large background region of 5999.0 pixels or a rate
of 22.768 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 19.65 mag. for a
4-arcsec aperture.
Found 5729.5 counts in the XRT position region of 198.0 pixels or a rate of
28.937 counts/pixel in a radius of 8.0 arcsec. The net count rate (using local
background region) at the XRT position is 8.064 +/- 0.535 (1-sigma) cps or
17.51 mag and a range from 17.44 to 17.59 mag. The 3-sigma UL at the XRT
position is 9.670 cps or 17.32 mag.
Found 1 srclist source(s) within 10.0" of the XRT position.
The brightest such source has ra= 246.7949 dec= 78.3908 mag=17.32 sep=7.12".
The closest srclist source has ra= 246.7949 dec= 78.3908 mag=17.32 sep=7.12".
Found 1 Genie source(s) within 10.0" of the XRT position. The brightest such
source has ra= 246.7953 dec= 78.3907 mag=16.88 sep=7.35". The closest Genie
source has ra= 246.7953 dec= 78.3907 mag=16.88 sep=7.35".
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 150 seconds with the White filter
starting 871 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 16:27:10.87 = 246.79531
DEC(J2000) = +78:23:26.7 = 78.39074
with a 90%-confidence error radius of about 0.61 arc sec. This position is 7.35
arc sec. from the center of the XRT error circle. The estimated magnitude is
16.88 with a 1-sigma error of about 0.14. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.04.
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?
622764334 871 WHITE srclist found no candidates.
622764334 871 WHITE image found no candidates.
List afterglow candidates for other finding charts.
622763544 81 WHITE srclist found no candidates.
622763544 81 WHITE image found no candidates.
622763756 293 U srclist found no candidates.
622763756 293 U image found no candidates.
------- Tokens for Quick GCN -------
CATALOG_TYPE: IMAGE
FILTER: white
GRB_DEC: 78.39053
GRB_ERROR: 5
GRB_RA: 246.78521
IMAGE_START_TIME: 22:05:29
MAGNITUDE: 17.3
MAG_ERROR: 3.0
MESSAGE_TYPE: NACK
SOURCE: XRT