image overlap message for exposure 1 of trigger 852903
uvot_overlap.pl vrs. 2010-12-20b fem started at 180812d12h31m44s820240usUT
The observation of trigger 852903 started 2018-08-12T08:24:44.1
Examining file ./852903_g133_uvot_sky_image.fits
The exposure ID is 555755084
The exposure time is 149.868 (seconds)
The filter is WHITE.
The uvot region is centered at (245.8716,74.6694) with a roll angle of 287.2
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 (245.8860,74.6700) with a radius of 3.000 arc min
This is 0.231 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 (245.8347,74.6647) with a radius of 0.028 arc min
This is 0.649 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 1 of trigger 852903
find_uvot_ag.pl vrs. 2017-02-17 fem started at 180812d12h31m47s777000usUT
Observation start time is 2018-08-12T08:24:44.1
Examining file ./852903_g133_uvot_catalog_image.fits
The exposure ID is 555755084
The exposure is 149.868 sec.
The bin size is 2 pixels
The filter is WHITE
There are 3 detected source(s) for 852903_g133
Aspect correction adds -0.00216 degrees (-0.519 sec of time = -2.06 arc sec) to RA
Aspect correction adds 0.00094 degrees ( 3.39 arcsec) to Dec
Total aspect correction is 3.97 arcsec
Star catalogs centered at 245.8777 , 74.6697 with radius 2.28 arc min.
n_usno: 59 n_gsc: 0
Bright star catalog has no entries brighter than 12 mag
Mean distance difference (CAT_DELTA) for 2 matched entries is 0.231" for 852903_g133
Mean and std. dev of mag. difference (MAG_DELTA) are 1.341 and 0.253 for 852903_g133
Found 1 entries without IDs and 1 entries that are acceptable afterglow candidates for 852903_g133.
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=245.8860 (16:23:32.64) DEC=74.6700 (+74:40:12.0)
XRT distances are from RA=245.8347 (16:23:20.32) DEC=74.6647 (+74:39:53.0)
*** WARNING 33 per cent of entries have no IDs.
-----------------
Entry 0 in the list of sources is a candidate afterglow for 852903_g133 with genie
ra=245.83501 (16:23:20.40) dec=74.66469 (+74:39:52.9) +/- 1.1" mag=20.40+/-0.30
dist=0.3 REFID=3 major=0.9 minor=0.9 flag=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)
uvot_check_outside found 13 of 13 good pixels
##### This source remains a candidate #####
It has no entries within 3.5" or brighter than 12 mag
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=245.83501 (16:23:20.40) dec=74.66469 (+74:39:52.9) +/- 1.1" mag=20.40+/-0.30 dist=0.3 REFID=3 flag=0
There are 1.6963605E+05 counts in the bkg source region of 6196.0000 pixels.
Rate in bkg region from 0 to 45 arcsec is 27.378 counts/pixel (5-sig UL in 4" is 19.55 mag) for 852903_g133
There are 5540.6250 counts in the xrt source region of 197.00000 pixels.
Rate in xrt region with 8 arcsec radius is 28.125 counts/pixel for 852903_g133
There are 34359.004 counts in the xrt_bkg source region of 1246.0000 pixels.
Rate in xrt_bkg region from 15 to 25 arcsec is 27.575 counts/pixel (5-sig UL in 4" is 19.55 mag) for 852903_g133
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 20.11, 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: 852903_555755084_180812d12h31m47s777000usUT_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(245.8716,74.6694,45")
fk5;-circle(245.83500793085,74.664691838726,6")
Region file: 852903_555755084_180812d12h31m47s777000usUT_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(245.83467,74.66472,8")
Region file: 852903_555755084_180812d12h31m47s777000usUT_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(245.83467,74.66472,25")
fk5;-circle(245.83467,74.66472,15")
image paragraph message for exposure 1 of trigger 852903
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 GRB180812 (Swift/BAT trigger 852903) at 08:22:30 UT,
---- UVOT paragraph for Joint or Stand-alone Circular ----
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 112 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 852903 ------
uvot_gcn_auto.pl vrs. 2016-09-07 fem at 180812d12h31m50s875178usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=852903
-expid=555755084 -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/852903/
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 555755084.05994 or about 2018:224:08:24:39 UT
Found 400 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 7% of the srclist region. Found 20 sources in
srclist catalog. Found 0 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 3 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
20.11 mag. Found 55 stars in largest star catalog for Genie image region. The
stars will eliminate afterglows from about 7% of the Genie image region.
Genie image analysis:
Found 169636.0 counts in the large background region of 6196.0 pixels or a rate
of 27.378 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 19.55 mag. for a
4-arcsec aperture.
Found 5540.6 counts in the XRT position region of 197.0 pixels or a rate of
28.125 counts/pixel in a radius of 8.0 arcsec. The net count rate (using local
background region) at the XRT position is 0.722 +/- 0.533 (1-sigma) cps or
20.13 mag and a range from 19.53 to 21.59 mag. The 3-sigma UL at the XRT
position is 2.322 cps or 18.87 mag. The closest srclist source has ra= 245.7896
dec= 74.6593 mag=18.75 sep=47.20".
Found 1 Genie source(s) within 10.0" of the XRT position. The brightest such
source has ra= 245.8350 dec= 74.6647 mag=20.40 sep=0.34". The closest Genie
source has ra= 245.8350 dec= 74.6647 mag=20.40 sep=0.34".
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 112 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 16:23:20.40 = 245.83501
DEC(J2000) = +74:39:52.9 = 74.66469
with a 90%-confidence error radius of about 1.10 arc sec. This position is 0.34
arc sec. from the center of the XRT error circle. The estimated magnitude is
20.40 with a 1-sigma error of about 0.30. 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?
555755084 112 WHITE srclist found no candidates.
555755084 112 WHITE 245.83501 74.66469 20.40/20.1 0.3 image Yes
List afterglow candidates for other finding charts.
555755242 270 U srclist found no candidates.
555755242 270 U image found no candidates.
555755844 872 WHITE srclist found no candidates.
555755844 872 WHITE image found no candidates.
------- Tokens for Quick GCN -------
CATALOG_TYPE: IMAGE
FILTER: white
GRB_DEC: 74.66472
GRB_ERROR: 5
GRB_RA: 245.83467
IMAGE_START_TIME: 08:24:39
MAGNITUDE: 18.9
MAG_ERROR: 3.0
MESSAGE_TYPE: NACK
SOURCE: XRT