srclist overlap message for exposure 1 of trigger 1044426


uvot_overlap.pl vrs. 2010-12-20b fem started at 210421d15h24m30s781851usUT

The observation of trigger 1044426 started 2021-04-21T00:29:33.6
Examining file ./1044426_g122_uvot_sky_srclist.fits
The exposure ID is 640657773
The exposure time is undefined.
The filter is WHITE.

The uvot region is centered at (104.9024,4.9367) with a roll angle of 281.0
It is square with sides of 8.03 arc min. for an area of 64.51 sq arc min

The BAT error circle is centered at (104.9080,4.9340) with a radius of 3.000 arc min
This is 0.373 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 28.27 sq. arc min or 1.00 of the BAT error circle

The XRT error circle is centered at (104.8744,4.9223) with a radius of 0.040 arc min
This is 1.880 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



srclist afterglow message for exposure 1 of trigger 1044426


find_uvot_ag.pl vrs. 2020-10-30 fem started at 210421d15h24m31s967368usUT

Observation start time is 2021-04-21T00:29:33.6
Examining file ./1044426_g122_uvot_catalog_srclist.fits
The exposure ID is 640657773
The exposure is 149.846 sec.
The bin size is 2 pixels
The filter is WHITE
There are 190 detected source(s) for 1044426_g122
*** WARNING -- the sources have filled the available telemetry buffer (190).
srclist_overlap returned: bat_overlap 1.000
srclist_overlap returned: xrt_overlap 1.000
Dimmest detected source in 1044426_g122 has mag 18.98
Aspect correction adds -0.00133 degrees (-0.318 sec of time = -4.75 arc sec) to RA
Aspect correction adds -0.00000 degrees (-0.00 arcsec) to Dec
Total aspect correction is 4.75 arcsec
Star catalogs centered at 104.9027 , 4.9379 with radius 6.37 arc min.
n_usno: 1298 n_gsc: 0
*** WARNING -- bright star catalog has 4 entries brighter than 12 mag
The brightest has mag 11.59852
                        RA                      DEC              Mag  Color
bright star  0: 104.93296 (06:59:43.91)   4.90741 (+04:54:26.7) 11.74 USNO-V
bright star  1: 104.88413 (06:59:32.19)   4.84818 (+04:50:53.5) 11.89 USNO-V
bright star  2: 104.84170 (06:59:22.01)   4.86455 (+04:51:52.4) 11.60 USNO-V
bright star  3: 104.91329 (06:59:39.19)   4.84284 (+04:50:34.2) 11.79 USNO-V
Mean distance difference (CAT_DELTA) for 185 matched entries is 0.575" for 1044426_g122
Mean and std. dev of mag. difference (MAG_DELTA) are 1.827 and 0.423 for 1044426_g122
Found 6 entries without IDs and 3 entries that are acceptable afterglow candidates for 1044426_g122.
Acceptable entries have no ID, XRT distances < 6", and are > 0.8*(80 - 10*(mag-6))" from any bright star
from any bright star and >21.6" from other rejected sources.
0 sources matched bright stars.
Magnitude criteria will be applied later.
BAT distances are from RA=104.9080 (06:59:37.92) DEC= 4.9340 (+04:56:02.4)
XRT distances are from RA=104.8744 (06:59:29.86) DEC= 4.9223 (+04:55:20.4)

-----------------
Entry 5 in the list of sources is a candidate afterglow for 1044426_g122 with 3x3 stamp
 ra=104.88669 (06:59:32.81) dec=4.91997 (+04:55:11.9) +/- 1.1" mag=17.08+/-0.35
 dist=44.8 REFID=44
*** The position of this source is inconsistent with the XRT position.
    The position is 91.6 arc sec from the BAT position.
 src: 5 distr. of nearby unmatched sources: 1 1 0 0 0 
Found 6 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 
  104.8876   4.9224   9.2    -1 USNO-B1  18.04  17.41  17.69
  104.8903   4.9194  12.9    -1 USNO-B1  16.62  15.33  15.90
  104.8873   4.9197   2.3    -1 USNO-B1  14.86  14.07  14.42 *
  104.8838   4.9206  10.7    -1 USNO-B1  19.92  18.88  19.34
  104.8818   4.9213  18.2    -1 USNO-B1  20.25  18.80  19.44
  104.8832   4.9163  18.2    -1 USNO-B1  18.38  18.02  18.18
Due to star catalog entries marked with *, this is probably NOT the afterglow
    These entries are within 4" or brighter than 13 mag

-----------------
Entry 6 in the list of sources is a candidate afterglow for 1044426_g122 with 1x1 stamp
 ra=104.88785 (06:59:33.09) dec=4.91902 (+04:55:08.5) +/- 1.1" mag=18.08+/-0.35
 dist=49.6 REFID=115
*** The position of this source is inconsistent with the XRT position.
    The position is 90.2 arc sec from the BAT position.
 src: 6 distr. of nearby unmatched sources: 1 1 0 0 0 
Found 5 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 
  104.8876   4.9224  12.1    -1 USNO-B1  18.04  17.41  17.69
  104.8903   4.9194   8.8    -1 USNO-B1  16.62  15.33  15.90
  104.8873   4.9197   3.3    -1 USNO-B1  14.86  14.07  14.42 *
  104.8838   4.9206  15.7    -1 USNO-B1  19.92  18.88  19.34
  104.8832   4.9163  19.3    -1 USNO-B1  18.38  18.02  18.18
Due to star catalog entries marked with *, this is probably NOT the afterglow
    These entries are within 4" or brighter than 13 mag

-----------------
Entry 94 in the list of sources is a candidate afterglow for 1044426_g122 with 3x3 stamp
 ra=104.90565 (06:59:37.36) dec=4.96802 (+04:58:04.9) +/- 1.1" mag=16.35+/-0.35
 dist=199.0 REFID=20
*** The position of this source is inconsistent with the XRT position.
    The position is 122.8 arc sec from the BAT position.
 src: 94 distr. of nearby unmatched sources: 1 0 0 0 0 
Found 5 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 
  104.9007   4.9672  18.2    -1 USNO-B1  19.62  18.82  19.18
  104.9059   4.9675   2.2    -1 USNO-B1  14.34  13.84  14.07 *
  104.9102   4.9678  16.4    -1 USNO-B1  19.96  18.36  19.07
  104.9065   4.9709  10.7    -1 USNO-B1  99.99  18.69  99.99
  104.9055   4.9714  12.1    -1 USNO-B1  18.63  17.41  17.95
Due to star catalog entries marked with *, this is probably NOT the afterglow
    These entries are within 4" or brighter than 13 mag

Found 0 entries in star catalog(s) within 10" of the XRT position.

List UVOT sources within 10" of the XRT position:

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 19.22, XRT distances < 6",
are > ~(80 - 10*(mag-6))" from any bright star, and have had duplicates removed.

SUMMARY: 0 good candidate(s) found.



srclist paragraph message for exposure 1 of trigger 1044426


SRCLIST PROBLEM: srclist filled telemetry buffer

WARNING -- because of the LARGE EXTINCTION, results should be used cautiously.

------ Start for Possible Stand-alone Circular ----

In response to GRB210421 (Swift/BAT trigger 1044426) at 00:27:30 UT,

---- UVOT paragraph for Joint or Stand-alone Circular ----

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 96 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 large, but uncertain, extinction expected.

------- notes for trigger 1044426 ------
uvot_gcn_auto.pl vrs. 2020-10-27 fem at 210421d15h24m43s336886usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=1044426
-expid=640657773 -meonly -msg_srclist
Results from standard processing of UVOT TDRSS data for this trigger should be
available at
http://heasarc.gsfc.nasa.gov/docs/swift/uvot_tdrss/1044426/
Links to data for all triggers can be found at
http://heasarc.gsfc.nasa.gov/docs/swift/uvot_tdrss/

Unreliable extinction found for xrt position. XRT position found for srclist.
XRT position found for Genie image. BAT position found.

UVOT exposure began at MET 640657773.59262 or about 2021:111:00:29:28 UT

Found 1294 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 22% of the srclist region. Found 190 sources in
srclist catalog. WARNING -- srclist catalog buffer filled. Found 6 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 39 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 20.45 mag. Found 239 stars in largest star
catalog for Genie image region. The stars will eliminate afterglows from about
22% of the Genie image region.

Genie image analysis:
Found 79423.3 counts in the large background region of 5438.0 pixels or a rate
of 14.605 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 19.72 mag. for a
4-arcsec aperture.
Found 2884.5 counts in the XRT position region of 201.0 pixels or a rate of
14.351 counts/pixel in a radius of 8.0 arcsec. The net count rate (using local
background region) at the XRT position is -0.362 +/- 0.391 (1-sigma) cps. The
3-sigma UL at the XRT position is 1.174 cps or 19.43 mag. The number of srclist
sources filled the available telemetry. The weakest source detected was 18.98
mag. The closest srclist source has ra= 104.8729 dec= 4.9176 mag=17.70
sep=17.84". The closest Genie source has ra= 104.8728 dec= 4.9175 mag=17.04
sep=18.23".

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?
640657773   95 WHITE srclist found no candidates.
640657773   95 WHITE image found no candidates.
List afterglow candidates for other finding charts.

------- Tokens for Quick GCN -------

CATALOG_TYPE: IMAGE
FILTER: white
GRB_DEC: 4.92233
GRB_ERROR: 6
GRB_RA: 104.87442
IMAGE_START_TIME: 00:29:28
MAGNITUDE: 19.4
MAG_ERROR: 3.0
MESSAGE_TYPE: NACK
SOURCE: XRT