image overlap message for exposure 1 of trigger 1000926
uvot_overlap.pl vrs. 2010-12-20b fem started at 201020d13h07m59s511762usUT
The observation of trigger 1000926 started 2020-10-20T05:50:16.2
Examining file ./1000926_g169_uvot_sky_image.fits
The exposure ID is 624865816
The exposure time is 149.857 (seconds)
The filter is WHITE.
The uvot region is centered at (261.2402,31.4235) with a roll angle of 241.5
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 (261.2460,31.4250) with a radius of 3.000 arc min
This is 0.308 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 (261.2283,31.4280) with a radius of 0.030 arc min
This is 0.671 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 1000926
find_uvot_ag.pl vrs. 2017-02-17 fem started at 201020d13h08m14s505039usUT
Observation start time is 2020-10-20T05:50:16.2
Examining file ./1000926_g169_uvot_catalog_image.fits
The exposure ID is 624865816
The exposure is 149.857 sec.
The bin size is 2 pixels
The filter is WHITE
There are 11 detected source(s) for 1000926_g169
Aspect correction adds -0.00212 degrees (-0.509 sec of time = -6.51 arc sec) to RA
Aspect correction adds -0.00069 degrees (-2.47 arcsec) to Dec
Total aspect correction is 6.97 arcsec
Star catalogs centered at 261.2378 , 31.4241 with radius 2.57 arc min.
n_usno: 69 n_gsc: 0
Bright star catalog has no entries brighter than 12 mag
Mean distance difference (CAT_DELTA) for 9 matched entries is 0.521" for 1000926_g169
Mean and std. dev of mag. difference (MAG_DELTA) are 0.709 and 0.478 for 1000926_g169
Found 2 entries without IDs and 2 entries that are acceptable afterglow candidates for 1000926_g169.
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=261.2460 (17:24:59.04) DEC=31.4250 (+31:25:30.0)
XRT distances are from RA=261.2283 (17:24:54.78) DEC=31.4280 (+31:25:40.9)
-----------------
Entry 2 in the list of sources is a candidate afterglow for 1000926_g169 with genie
ra=261.24614 (17:24:59.07) dec=31.43802 (+31:26:16.9) +/- 0.9" mag=20.96+/-0.27
dist=65.7 REFID=7 major=1.1 minor=1.1 flag=0
*** The position of this source is inconsistent with the XRT position.
The position is 46.9 arc sec from the BAT position.
Found 2 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)
RA Dec Sep. Match USNO/ USNO-B USNO-R USNO-V
GSC GSC-F GSC-J GSC-V
261.2473 31.4359 8.5 -1 USNO-B1 20.69 19.86 20.23
261.2466 31.4373 2.9 -1 USNO-B1 20.88 99.99 99.99 *
Due to star catalog entries marked with *, this is probably NOT the afterglow
These entries are within 3.5" or brighter than 12 mag
-----------------
Entry 3 in the list of sources is a candidate afterglow for 1000926_g169 with genie
ra=261.22779 (17:24:54.67) dec=31.42834 (+31:25:42.0) +/- 0.6" mag=18.14+/-0.15
dist=1.8 REFID=9 major=0.9 minor=0.9 flag=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
261.2270 31.4330 16.8 -1 USNO-B1 21.25 20.07 20.59
uvot_check_outside found 14 of 14 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=261.22779 (17:24:54.67) dec=31.42834 (+31:25:42.0) +/- 0.6" mag=18.14+/-0.15 dist=1.8 REFID=9 flag=0
There are 43444.520 counts in the bkg source region of 6210.0000 pixels.
Rate in bkg region from 0 to 45 arcsec is 6.996 counts/pixel (5-sig UL in 4" is 20.29 mag) for 1000926_g169
There are 1105.0619 counts in the src source region of 50.000000 pixels.
Rate in src region with 4 arcsec radius is 22.101 counts/pixel for 1000926_g169
There are 8680.5811 counts in the cand_src_bkg source region of 1244.0000 pixels.
Rate in cand_src_bkg region from 15 to 25 arcsec is 6.978 counts/pixel (5-sig UL in 4" is 20.29 mag) for 1000926_g169
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 20.85, XRT distances < 5",
are > ~(80 - 10*(mag-6))" from any bright star, and have had duplicates removed.
SUMMARY: 1 good candidate(s) found.
Region file: 1000926_624865816_201020d13h08m14s505039usUT_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(261.2402,31.4235,45")
fk5;-circle(261.255519650095,31.4266487401622,6")
fk5;-circle(261.227786759448,31.4283375997495,6")
Region file: 1000926_624865816_201020d13h08m14s505039usUT_cand_src.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(261.227786759448,31.4283375997495,4")
Region file: 1000926_624865816_201020d13h08m14s505039usUT_cand_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(261.227786759448,31.4283375997495,25")
fk5;-circle(261.227786759448,31.4283375997495,15")
image paragraph message for exposure 1 of trigger 1000926
------ Start for Possible Stand-alone Circular ----
In response to GRB201020 (Swift/BAT trigger 1000926) at 05:47:26 UT,
---- UVOT paragraph for Joint or Stand-alone Circular ----
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 144 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 17:24:54.67 = 261.22779
DEC(J2000) = +31:25:42.0 = 31.42834
with a 90%-confidence error radius of about 0.62 arc sec. This position is 1.8
arc sec. from the center of the XRT error circle. The estimated magnitude is
18.14 with a 1-sigma error of about 0.15. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.04.
------- notes for trigger 1000926 ------
uvot_gcn_auto.pl vrs. 2016-09-07 fem at 201020d13h08m18s458479usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=1000926
-expid=624865816 -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/1000926/
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 624865816.20964 or about 2020:294:05:50:11 UT
Found 495 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 8% of the srclist region. Found 79 sources in
srclist catalog. Found 21 srclist source(s) without IDs. There are 1 good
candidate(s) in the srclist catalog. Good candidates must be brighter than
19.22 mag.
Found 11 source(s) in Genie image catalog. 1 source(s) are within 10.0" of the
xrt position. Found 2 Genie image source(s) without IDs. There are 1 good
candidate(s) in the Genie image catalog. Good candidates must be brighter than
20.85 mag. Found 65 stars in largest star catalog for Genie image region. The
stars will eliminate afterglows from about 6% of the Genie image region.
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?
624865816 144 WHITE 261.22761 31.42828 18.67/19.2 2.2 srclist Yes
624865816 144 WHITE 261.22779 31.42834 18.14/20.9 1.8 image Yes
List afterglow candidates for other finding charts.
624865974 302 U srclist found no candidates.
624865974 302 U 261.22771 31.42832 19.95/20.7 2.0 image Yes
------- Tokens for Quick GCN -------
CATALOG_TYPE: IMAGE
FILTER: white
GRB_DEC: 31.42834
GRB_ERROR: 0.62
GRB_RA: 261.22779
IMAGE_START_TIME: 05:50:11
MAGNITUDE: 18.14
MAG_ERROR: 0.15
MESSAGE_TYPE: ACK
SOURCE: XRT