image overlap message for exposure 1 of trigger 1071488
uvot_overlap.pl vrs. 2010-12-20b fem started at 210901d20h10m35s509524usUT
The observation of trigger 1071488 started 2021-09-01T15:07:41.6
Examining file ./1071488_g184_uvot_sky_image.fits
The exposure ID is 652201661
The exposure time is 149.868 (seconds)
The filter is WHITE.
The uvot region is centered at (295.2623,-76.9321) with a roll angle of 227.7
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 (295.2920,-76.9320) with a radius of 3.000 arc min
This is 0.403 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 (295.2780,-76.9266) with a radius of 0.042 arc min
This is 0.393 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
image afterglow message for exposure 1 of trigger 1071488
find_uvot_ag.pl vrs. 2020-10-30 fem started at 210901d20h10m41s865044usUT
Observation start time is 2021-09-01T15:07:41.6
Examining file ./1071488_g184_uvot_catalog_image.fits
The exposure ID is 652201661
The exposure is 149.868 sec.
The bin size is 2 pixels
The filter is WHITE
There are 14 detected source(s) for 1071488_g184
Aspect correction adds -0.00379 degrees (-0.908 sec of time = -3.09 arc sec) to RA
Aspect correction adds -0.00085 degrees (-3.05 arcsec) to Dec
Total aspect correction is 4.34 arcsec
Star catalogs centered at 295.2830 , -76.9304 with radius 2.53 arc min.
n_usno: 107 n_gsc: 0
Bright star catalog has no entries brighter than 12 mag
Mean distance difference (CAT_DELTA) for 14 matched entries is 0.321" for 1071488_g184
Mean and std. dev of mag. difference (MAG_DELTA) are 0.993 and 0.371 for 1071488_g184
Found 0 entries without IDs and 0 entries that are acceptable afterglow candidates for 1071488_g184.
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.
Magnitude criteria will be applied later.
BAT distances are from RA=295.2920 (19:41:10.08) DEC=-76.9320 (-76:55:55.2)
XRT distances are from RA=295.2780 (19:41:06.73) DEC=-76.9266 (-76:55:35.9)
Found 1 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
295.2863 -76.9282 8.8 -1 USNO-B1 17.53 16.69 17.06
The closest star is 8.84" away.
List UVOT sources within 10" of the XRT position:
Matched source ra=295.28628 (19:41:08.71) dec=-76.92818 (-76:55:41.4) +/- 0.6" mag=17.80+/-0.14 dist=8.7 REFID=8 flag=0
There are 47485.074 counts in the bkg source region of 5557.0000 pixels.
Rate in bkg region from 0 to 45 arcsec is 8.545 counts/pixel (5-sig UL in 4" is 20.18 mag) for 1071488_g184
There are 1987.5034 counts in the xrt source region of 199.00000 pixels.
Rate in xrt region with 8 arcsec radius is 9.987 counts/pixel for 1071488_g184
There are 7969.2734 counts in the xrt_bkg source region of 922.00000 pixels.
Rate in xrt_bkg region from 15 to 25 arcsec is 8.643 counts/pixel (5-sig UL in 4" is 20.18 mag) for 1071488_g184
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 20.74, XRT distances < 6.25",
are > ~(80 - 10*(mag-6))" from any bright star, and have had duplicates removed.
SUMMARY: 0 good candidate(s) found.
Region file: 1071488_652201661_210901d20h10m41s865044usUT_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(295.2623,-76.9321,45")
fk5;-circle(295.286279805739,-76.9281786688461,6")
fk5;-circle(295.291779079045,-76.9221379659285,6")
fk5;-circle(295.305753609515,-76.9241957453684,6")
fk5;-circle(295.296873268919,-76.9318018624048,6")
fk5;-circle(295.253822184049,-76.926635123426,6")
fk5;-circle(295.286903877735,-76.9365516767156,6")
fk5;-circle(295.309547198037,-76.9368324745502,6")
fk5;-circle(295.212703259012,-76.9351687920731,6")
Region file: 1071488_652201661_210901d20h10m41s865044usUT_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(295.27804,-76.92664,8")
Region file: 1071488_652201661_210901d20h10m41s865044usUT_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(295.27804,-76.92664,25")
fk5;-circle(295.27804,-76.92664,15")
fk5;-circle(295.291779079045,-76.9221379659285,6")
fk5;-circle(295.305753609515,-76.9241957453684,6")
fk5;-circle(295.296873268919,-76.9318018624048,6")
fk5;-circle(295.253822184049,-76.926635123426,6")
image paragraph message for exposure 1 of trigger 1071488
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 GRB210901 (Swift/BAT trigger 1071488) at 15:04:36 UT,
---- UVOT paragraph for Joint or Stand-alone Circular ----
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 157 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
0.200.
------- notes for trigger 1071488 ------
uvot_gcn_auto.pl vrs. 2020-10-27 fem at 210901d20h10m48s675161usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=1071488
-expid=652201661 -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/1071488/
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 652201661.59562 or about 2021:244:15:07:36 UT
Found 702 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 12% of the srclist region. Found 72 sources in
srclist catalog. Found 10 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 14 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
20.74 mag. Found 103 stars in largest star catalog for Genie image region. The
stars will eliminate afterglows from about 11% of the Genie image region.
Genie image analysis:
Found 47485.1 counts in the large background region of 5557.0 pixels or a rate
of 8.545 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 20.01 mag. for a
4-arcsec aperture.
Found 1987.5 counts in the XRT position region of 199.0 pixels or a rate of
9.987 counts/pixel in a radius of 8.0 arcsec. The net count rate (using local
background region) at the XRT position is 1.783 +/- 0.324 (1-sigma) cps or
18.98 mag and a range from 18.79 to 19.19 mag. The 3-sigma UL at the XRT
position is 2.754 cps or 18.50 mag.
Found 1 srclist source(s) within 10.0" of the XRT position.
The brightest such source has ra= 295.2863 dec= -76.9282 mag=18.49 sep=8.70".
The closest srclist source has ra= 295.2863 dec= -76.9282 mag=18.49 sep=8.70".
Found 1 Genie source(s) within 10.0" of the XRT position. The brightest such
source has ra= 295.2863 dec= -76.9282 mag=17.80 sep=8.70". The closest Genie
source has ra= 295.2863 dec= -76.9282 mag=17.80 sep=8.70".
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 157 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 19:41:08.71 = 295.28628
DEC(J2000) = -76:55:41.4 = -76.92818
with a 90%-confidence error radius of about 0.62 arc sec. This position is 8.70
arc sec. from the center of the XRT error circle. The estimated magnitude is
17.80 with a 1-sigma error of about 0.14. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.200.
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?
652201661 157 WHITE srclist found no candidates.
652201661 157 WHITE image found no candidates.
List afterglow candidates for other finding charts.
652201819 315 U srclist found no candidates.
652201819 315 U image found no candidates.
652202373 869 WHITE srclist found no candidates.
652202373 869 WHITE image found no candidates.
------- Tokens for Quick GCN -------
CATALOG_TYPE: IMAGE
FILTER: white
GRB_DEC: -76.92664
GRB_ERROR: 6.25
GRB_RA: 295.27804
IMAGE_START_TIME: 15:07:36
MAGNITUDE: 18.5
MAG_ERROR: 3.0
MESSAGE_TYPE: NACK
SOURCE: XRT