image overlap message for exposure 2 of trigger 1071488
uvot_overlap.pl vrs. 2010-12-20b fem started at 210901d20h10m36s839076usUT
The observation of trigger 1071488 started 2021-09-01T15:10:19.6
Examining file ./1071488_g342_uvot_sky_image.fits
The exposure ID is 652201819
The exposure time is 249.935 (seconds)
The filter is U.
*** Warning -- found 13653 null pixels in the image.
The uvot region is centered at (295.2757,-76.9312) 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 0.226 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 at most 6.55 sq. arc min or 0.23 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 0.273 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 0.00 sq. arc min or 0.00 of the XRT error circle
image afterglow message for exposure 2 of trigger 1071488
find_uvot_ag.pl vrs. 2020-10-30 fem started at 210901d20h10m54s153608usUT
Observation start time is 2021-09-01T15:10:19.6
Examining file ./1071488_g342_uvot_catalog_image.fits
The exposure ID is 652201819
The exposure is 249.935 sec.
The bin size is 2 pixels
The filter is U
There are 4 detected source(s) for 1071488_g342
Aspect correction adds -0.00522 degrees (-1.254 sec of time = -4.26 arc sec) to RA
Aspect correction adds -0.00039 degrees (-1.40 arcsec) to Dec
Total aspect correction is 4.49 arcsec
Star catalogs centered at 295.2880 , -76.9377 with radius 2.33 arc min.
n_usno: 94 n_gsc: 0
Bright star catalog has no entries brighter than 12 mag
Mean distance difference (CAT_DELTA) for 4 matched entries is 0.388" for 1071488_g342
Mean and std. dev of mag. difference (MAG_DELTA) are 1.441 and 0.806 for 1071488_g342
Found 0 entries without IDs and 0 entries that are acceptable afterglow candidates for 1071488_g342.
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:
There are 8655.7656 counts in the bkg source region of 2547.0000 pixels.
Rate in bkg region from 0 to 45 arcsec is 3.398 counts/pixel (5-sig UL in 4" is 19.80 mag) for 1071488_g342
There are 0.0000000 counts in the xrt source region of 0.0000000 pixels.
There are 268.52933 counts in the xrt_bkg source region of 75.000000 pixels.
Rate in xrt_bkg region from 15 to 25 arcsec is 3.580 counts/pixel (5-sig UL in 4" is 19.77 mag) for 1071488_g342
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 20.36, 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_652201819_210901d20h10m54s153608usUT_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(295.2757,-76.9312,45")
fk5;-circle(295.287229800241,-76.9365224342652,6")
Region file: 1071488_652201819_210901d20h10m54s153608usUT_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_652201819_210901d20h10m54s153608usUT_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")
image paragraph message for exposure 2 of trigger 1071488
IMAGE PROBLEM: no overlap
------ 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 250 seconds with the U filter starting
315 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 none of the
XRT error circle. 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 18.0 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 210901d20h11m00s502649usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=1071488
-expid=652201819 -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 652201819.6201 or about 2021:244:15:10:14 UT
Found 649 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 12% of the srclist region. Found 42 sources in
srclist catalog. Found 5 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 4 source(s) in Genie image catalog. 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 20.36 mag. Found 90 stars in largest star catalog for
Genie image region. The stars will eliminate afterglows from about 11% of the
Genie image region. The Genie image is INCOMPLETE with 13653 null pixels.
Genie image analysis:
Found 8655.8 counts in the large background region of 2547.0 pixels or a rate
of 3.398 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 19.64 mag. for a
4-arcsec aperture.
Found 1 srclist source(s) within 10.0" of the XRT position.
The brightest such source has ra= 295.2870 dec= -76.9282 mag=18.62 sep=9.25".
The closest srclist source has ra= 295.2870 dec= -76.9282 mag=18.62 sep=9.25".
The closest Genie source has ra= 295.2872 dec= -76.9365 mag=18.69 sep=36.35".
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 250 seconds with the U filter starting
315 seconds after the BAT trigger. There is a candidate afterglow in the list
of sources generated on-board at
RA(J2000) = 19:41:08.87 = 295.28697
DEC(J2000) = -76:55:41.6 = -76.92823
with a 90%-confidence error radius of about 1.10 arc sec. This position is 9.25
arc sec. from the center of the XRT error circle. The estimated magnitude is
18.62 with a 1-sigma error of about 0.35. 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?
652201819 315 U srclist found no candidates.
652201819 315 U image found no candidates.
List afterglow candidates for other finding charts.
652201661 157 WHITE srclist found no candidates.
652201661 157 WHITE image found no candidates.
652202373 869 WHITE srclist found no candidates.
652202373 869 WHITE image found no candidates.
------- Tokens for Quick GCN -------
CATALOG_TYPE: SRCLIST
FILTER: u
GRB_DEC: -76.92664
GRB_ERROR: 6.25
GRB_RA: 295.27804
IMAGE_START_TIME: 15:10:14
MAGNITUDE: 18.0
MAG_ERROR: 3.0
MESSAGE_TYPE: NACK
SOURCE: XRT