image overlap message for exposure 1 of trigger 849018
uvot_overlap.pl vrs. 2010-12-20b fem started at 180721d15h34m37s845227usUT
The observation of trigger 849018 started 2018-07-21T11:09:09.5
Examining file ./849018_g140_uvot_sky_image.fits
The exposure ID is 553864149
The exposure time is 249.935 (seconds)
The filter is U.
The uvot region is centered at (347.7123,4.8563) with a roll angle of 59.6
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 (347.6950,4.8800) with a radius of 3.000 arc min
This is 1.758 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 6.71 sq. arc min or 0.24 of the BAT error circle
The XRT error circle is centered at (347.7117,4.8568) with a radius of 0.047 arc min
This is 0.048 arc min from the center of the uvot region
The area of the XRT error circle is 0.007 sq. arc min
The UVOT/XRT overlap is 0.007 sq. arc min or 1.00 of the XRT error circle
image afterglow message for exposure 1 of trigger 849018
find_uvot_ag.pl vrs. 2017-02-17 fem started at 180721d15h34m41s254812usUT
Observation start time is 2018-07-21T11:09:09.5
Examining file ./849018_g140_uvot_catalog_image.fits
The exposure ID is 553864149
The exposure is 249.935 sec.
The bin size is 2 pixels
The filter is U
There are 2 detected source(s) for 849018_g140
Aspect correction adds 0.00004 degrees (0.009 sec of time = 0.13 arc sec) to RA
Aspect correction adds -0.00039 degrees (-1.39 arcsec) to Dec
Total aspect correction is 1.39 arcsec
Star catalogs centered at 347.7104 , 4.8563 with radius 2.18 arc min.
n_usno: 44 n_gsc: 0
Bright star catalog has no entries brighter than 12 mag
Mean distance difference (CAT_DELTA) for 2 matched entries is 0.285" for 849018_g140
Mean and std. dev of mag. difference (MAG_DELTA) are 1.460 and 1.160 for 849018_g140
Found 0 entries without IDs and 0 entries that are acceptable afterglow candidates for 849018_g140.
Acceptable entries have no ID, XRT distances < 7", 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=347.6950 (23:10:46.80) DEC= 4.8800 (+04:52:48.0)
XRT distances are from RA=347.7117 (23:10:50.80) DEC= 4.8568 (+04:51:24.4)
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
347.7126 4.8585 6.8 -1 USNO-B1 17.41 16.29 16.78
The closest star is 6.82" away.
List UVOT sources within 10" of the XRT position:
Matched source ra=347.71260 (23:10:51.02) dec=4.85838 (+04:51:30.2) +/- 0.8" mag=17.24+/-0.15 dist=6.7 REFID=1 flag=0
There are 15268.329 counts in the bkg source region of 6194.0000 pixels.
Rate in bkg region from 0 to 45 arcsec is 2.465 counts/pixel (5-sig UL in 4" is 19.98 mag) for 849018_g140
There are 957.75378 counts in the xrt source region of 199.00000 pixels.
Rate in xrt region with 8 arcsec radius is 4.813 counts/pixel for 849018_g140
There are 3121.2554 counts in the xrt_bkg source region of 1243.0000 pixels.
Rate in xrt_bkg region from 15 to 25 arcsec is 2.511 counts/pixel (5-sig UL in 4" is 19.97 mag) for 849018_g140
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 20.53, XRT distances < 7",
are > ~(80 - 10*(mag-6))" from any bright star, and have had duplicates removed.
SUMMARY: 0 good candidate(s) found.
Region file: 849018_553864149_180721d15h34m41s254812usUT_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(347.7123,4.8563,45")
fk5;-circle(347.712595639806,4.85838371311701,6")
Region file: 849018_553864149_180721d15h34m41s254812usUT_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(347.71167,4.85678,8")
Region file: 849018_553864149_180721d15h34m41s254812usUT_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(347.71167,4.85678,25")
fk5;-circle(347.71167,4.85678,15")
image paragraph message for exposure 1 of trigger 849018
SRCLIST PROBLEM: srclist filled telemetry buffer
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 GRB180721 (Swift/BAT trigger 849018) at 11:06:48 UT,
---- UVOT paragraph for Joint or Stand-alone Circular ----
UVOT took a finding chart exposure of 250 seconds with the U filter starting
119 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 19.2 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 18.0 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.07.
------- notes for trigger 849018 ------
uvot_gcn_auto.pl vrs. 2016-09-07 fem at 180721d15h34m43s685494usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=849018
-expid=553864149 -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/849018/
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 553864149.51586 or about 2018:202:11:09:04 UT
Found 876 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 7% of the srclist region. Found 190 sources in
srclist catalog. WARNING -- srclist catalog buffer filled. Found 140 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 2 source(s) in Genie image catalog. 1 source(s) are within 10.0" of the
xrt position. 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
20.53 mag. Found 40 stars in largest star catalog for Genie image region. The
stars will eliminate afterglows from about 5% of the Genie image region.
Genie image analysis:
Found 15268.3 counts in the large background region of 6194.0 pixels or a rate
of 2.465 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 20.02 mag. for a
4-arcsec aperture.
Found 957.8 counts in the XRT position region of 199.0 pixels or a rate of
4.813 counts/pixel in a radius of 8.0 arcsec. The net count rate (using local
background region) at the XRT position is 1.832 +/- 0.129 (1-sigma) cps or
17.72 mag and a range from 17.65 to 17.80 mag. The 3-sigma UL at the XRT
position is 2.219 cps or 17.51 mag. The number of srclist sources filled the
available telemetry. The weakest source detected was 19.87 mag.
Found 1 srclist source(s) within 10.0" of the XRT position.
The brightest such source has ra= 347.7126 dec= 4.8584 mag=17.93 sep=6.67".
The closest srclist source has ra= 347.7126 dec= 4.8584 mag=17.93 sep=6.67".
Found 1 Genie source(s) within 10.0" of the XRT position. The brightest such
source has ra= 347.7126 dec= 4.8584 mag=17.24 sep=6.66". The closest Genie
source has ra= 347.7126 dec= 4.8584 mag=17.24 sep=6.66".
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
119 seconds after the BAT trigger. There is a candidate afterglow in the
rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 23:10:51.02 = 347.71260
DEC(J2000) = +04:51:30.2 = 4.85838
with a 90%-confidence error radius of about 0.75 arc sec. This position is 6.66
arc sec. from the center of the XRT error circle. The estimated magnitude is
17.24 with a 1-sigma error of about 0.15. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.07.
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?
553864149 119 U srclist found no candidates.
553864149 119 U image found no candidates.
List afterglow candidates for other finding charts.
553864901 871 U srclist found no candidates.
553864901 871 U image found no candidates.
------- Tokens for Quick GCN -------
CATALOG_TYPE: IMAGE
FILTER: u
GRB_DEC: 4.85678
GRB_ERROR: 7
GRB_RA: 347.71167
IMAGE_START_TIME: 11:09:04
MAGNITUDE: 17.5
MAG_ERROR: 3.0
MESSAGE_TYPE: NACK
SOURCE: XRT