image overlap message for exposure 1 of trigger 992444
uvot_overlap.pl vrs. 2010-12-20b fem started at 200821d13h23m47s298428usUT
The observation of trigger 992444 started 2020-08-21T13:18:03.3
Examining file 992444_g177_uvot_sky_image.fits
The exposure ID is 619708683
The exposure time is 149.879 (seconds)
The filter is WHITE.
The uvot region is centered at (353.5797,-48.2823) with a roll angle of 145.2
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 (353.5700,-48.2770) with a radius of 3.000 arc min
This is 0.503 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
Could not find the location of an XRT error circle
image afterglow message for exposure 1 of trigger 992444
find_uvot_ag.pl vrs. 2017-02-17 fem started at 200821d13h23m49s000495usUT
Observation start time is 2020-08-21T13:18:03.3
Examining file 992444_g177_uvot_catalog_image.fits
The exposure ID is 619708683
The exposure is 149.879 sec.
The bin size is 2 pixels
The filter is WHITE
There are 10 detected source(s) for 992444_g177
Aspect correction adds 0.00124 degrees (0.297 sec of time = 2.96 arc sec) to RA
Aspect correction adds -0.00186 degrees (-6.71 arcsec) to Dec
Total aspect correction is 7.34 arcsec
Star catalogs centered at 353.5794 , -48.2859 with radius 2.61 arc min.
n_usno: 34 n_gsc: 0
Bright star catalog has no entries brighter than 12 mag
*** WARNING -- no XRT distances are available.
Mean distance difference (CAT_DELTA) for 9 matched entries is 0.775" for 992444_g177
Mean and std. dev of mag. difference (MAG_DELTA) are 0.717 and 0.361 for 992444_g177
Found 1 entries without IDs and 1 entries that are acceptable afterglow candidates for 992444_g177.
Acceptable entries have no ID, BAT distance < 200" or XRT distance < 10", 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=353.5700 (23:34:16.80) DEC=-48.2770 (-48:16:37.2)
XRT distances are as reported in catalog file.
-----------------
Entry 4 in the list of sources is a candidate afterglow for 992444_g177 with genie
ra=353.60232 (23:34:24.56) dec=-48.27443 (-48:16:28.0) +/- 1.0" mag=20.83+/-0.25
dist=78.0 REFID=10 major=0.9 minor=0.8 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 12 of 12 good pixels
##### This source remains a candidate #####
It has no entries within 3.5" or brighter than 12 mag
There are 41857.043 counts in the bkg source region of 6244.0000 pixels.
Rate in bkg region from 0 to 45 arcsec is 6.704 counts/pixel (5-sig UL in 4" is 20.32 mag) for 992444_g177
Good candidates have no ID, acceptable profiles,
mag between 9.01 and 20.31, BAT distances < 200",
are > ~(80 - 10*(mag-6))" from any bright star, and have had duplicates removed.
SUMMARY: 0 good candidate(s) found.
Region file: 992444_619708683_200821d13h23m49s000495usUT_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(353.5797,-48.2823,45")
fk5;-circle(353.596729990962,-48.2870275614704,6")
image paragraph message for exposure 1 of trigger 992444
IMAGE PROBLEM: partial overlap
------ Start for Possible Stand-alone Circular ----
In response to GRB200821 (Swift/BAT trigger 992444) at 13:15:05 UT,
---- UVOT paragraph for Joint or Stand-alone Circular ----
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 152 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 25% of
the BAT 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
BAT 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
0.01.
------- notes for trigger 992444 ------
uvot_gcn_auto.pl vrs. 2016-09-07 fem at 200821d13h24m02s401546usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=992444
-expid=619708683 -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/992444/
Links to data for all triggers can be found at
http://heasarc.gsfc.nasa.gov/docs/swift/uvot_tdrss/
No XRT position found for srclist. No XRT position found for Genie image. BAT
position found.
UVOT exposure began at MET 619708683.26344 or about 2020:234:13:17:58 UT
Found 166 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 3% of the srclist region. Found 23 sources in
srclist catalog. Found 2 srclist source(s) without IDs. There are 0 good
candidate(s) in the srclist catalog. Good candidates must be brighter than
18.66 mag.
Found 10 source(s) in Genie image catalog. 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 20.31 mag. Found 30 stars in largest star
catalog for Genie image region. The stars will eliminate afterglows from about
3% of the Genie image region.
Genie image analysis:
Found 41857.0 counts in the large background region of 6244.0 pixels or a rate
of 6.704 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 20.32 mag. for a
4-arcsec aperture.
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?
619708683 151 WHITE 353.60722 -48.30090 20.96/18.7 123.9 srclist Yes
619708683 151 WHITE 353.60232 -48.27443 20.83/20.3 78.0 image Yes
List afterglow candidates for other finding charts.
------- Tokens for Quick GCN -------
CATALOG_TYPE: SRCLIST
FILTER: white
GRB_DEC: -48.27700
GRB_ERROR: 200
GRB_RA: 353.57000
IMAGE_START_TIME: 13:17:58
MAGNITUDE: 18.0
MAG_ERROR: 3.0
MESSAGE_TYPE: NACK
SOURCE: BAT