image overlap message for exposure 1 of trigger 895257
uvot_overlap.pl vrs. 2010-12-20b fem started at 190327d09h09m35s528123usUT
The observation of trigger 895257 started 2019-03-27T09:02:51.5
Examining file 895257_g153_uvot_sky_image.fits
The exposure ID is 575370171
The exposure time is 249.924 (seconds)
The filter is U.
The uvot region is centered at (314.6986,41.7752) with a roll angle of 116.3
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 (314.6980,41.8220) with a radius of 3.000 arc min
This is 2.805 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 3.70 sq. arc min or 0.13 of the BAT error circle
The XRT error circle is centered at (314.6953,41.7772) with a radius of 0.098 arc min
This is 0.189 arc min from the center of the uvot region
The area of the XRT error circle is 0.030 sq. arc min
The UVOT/XRT overlap is 0.030 sq. arc min or 1.00 of the XRT error circle
image afterglow message for exposure 1 of trigger 895257
find_uvot_ag.pl vrs. 2017-02-17 fem started at 190327d09h09m36s744718usUT
Observation start time is 2019-03-27T09:02:51.5
Examining file 895257_g153_uvot_catalog_image.fits
The exposure ID is 575370171
The exposure is 249.924 sec.
The bin size is 2 pixels
The filter is U
There are 10 detected source(s) for 895257_g153
Aspect correction adds 0.00121 degrees (0.291 sec of time = 3.26 arc sec) to RA
Aspect correction adds -0.00019 degrees (-0.67 arcsec) to Dec
Total aspect correction is 3.33 arcsec
Star catalogs centered at 314.6946 , 41.7715 with radius 2.43 arc min.
n_usno: 254 n_gsc: 0
Bright star catalog has no entries brighter than 12 mag
Mean distance difference (CAT_DELTA) for 10 matched entries is 0.382" for 895257_g153
Mean and std. dev of mag. difference (MAG_DELTA) are 2.452 and 1.454 for 895257_g153
Found 0 entries without IDs and 0 entries that are acceptable afterglow candidates for 895257_g153.
Acceptable entries have no ID, XRT distances < 14.75", 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=314.6980 (20:58:47.52) DEC=41.8220 (+41:49:19.2)
XRT distances are from RA=314.6953 (20:58:46.87) DEC=41.7772 (+41:46:37.9)
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
314.6981 41.7770 7.5 -1 USNO-B1 16.73 13.82 15.12
The closest star is 7.48" away.
List UVOT sources within 10" of the XRT position:
Matched source ra=314.69805 (20:58:47.53) dec=41.77701 (+41:46:37.2) +/- 0.7" mag=15.66+/-0.14 dist=7.4 REFID=4 flag=0
There are 39601.695 counts in the bkg source region of 5987.0000 pixels.
Rate in bkg region from 0 to 45 arcsec is 6.615 counts/pixel (5-sig UL in 4" is 19.44 mag) for 895257_g153
There are 2857.6963 counts in the xrt source region of 204.00000 pixels.
Rate in xrt region with 8 arcsec radius is 14.008 counts/pixel for 895257_g153
There are 8089.1782 counts in the xrt_bkg source region of 1214.0000 pixels.
Rate in xrt_bkg region from 15 to 25 arcsec is 6.663 counts/pixel (5-sig UL in 4" is 19.44 mag) for 895257_g153
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 19.99, XRT distances < 14.75",
are > ~(80 - 10*(mag-6))" from any bright star, and have had duplicates removed.
SUMMARY: 0 good candidate(s) found.
Region file: 895257_575370171_190327d09h09m36s744718usUT_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(314.6986,41.7752,45")
fk5;-circle(314.698048318274,41.7770118369422,6")
fk5;-circle(314.686379971179,41.7740692890847,6")
fk5;-circle(314.691863269356,41.765935851368,6")
Region file: 895257_575370171_190327d09h09m36s744718usUT_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(314.6953,+41.7772,8")
Region file: 895257_575370171_190327d09h09m36s744718usUT_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(314.6953,+41.7772,25")
fk5;-circle(314.6953,+41.7772,15")
fk5;-circle(314.686379971179,41.7740692890847,6")
image paragraph message for exposure 1 of trigger 895257
WARNING -- because of the LARGE EXTINCTION, results should be used cautiously.
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 GRB190327 (Swift/BAT trigger 895257) at 09:00:17 UT,
---- UVOT paragraph for Joint or Stand-alone Circular ----
UVOT took a finding chart exposure of 250 seconds with the U filter starting
131 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 large, but uncertain, extinction expected.
------- notes for trigger 895257 ------
uvot_gcn_auto.pl vrs. 2016-09-07 fem at 190327d09h10m00s094872usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=895257
-expid=575370171 -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/895257/
Links to data for all triggers can be found at
http://heasarc.gsfc.nasa.gov/docs/swift/uvot_tdrss/
Unreliable extinction found for bat position. 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 575370171.53334 or about 2019:086:09:02:46 UT
Found 3082 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 29% of the srclist region. Found 85 sources in
srclist catalog. Found 11 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 10 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
19.99 mag. Found 250 stars in largest star catalog for Genie image region. The
stars will eliminate afterglows from about 29% of the Genie image region.
Genie image analysis:
Found 39601.7 counts in the large background region of 5987.0 pixels or a rate
of 6.615 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 19.48 mag. for a
4-arcsec aperture.
Found 2857.7 counts in the XRT position region of 204.0 pixels or a rate of
14.008 counts/pixel in a radius of 8.0 arcsec. The net count rate (using local
background region) at the XRT position is 5.994 +/- 0.222 (1-sigma) cps or
16.44 mag and a range from 16.40 to 16.48 mag. The 3-sigma UL at the XRT
position is 6.660 cps or 16.32 mag.
Found 1 srclist source(s) within 10.0" of the XRT position.
The brightest such source has ra= 314.6980 dec= 41.7770 mag=16.02 sep=7.39".
The closest srclist source has ra= 314.6980 dec= 41.7770 mag=16.02 sep=7.39".
Found 1 Genie source(s) within 10.0" of the XRT position. The brightest such
source has ra= 314.6981 dec= 41.7770 mag=15.66 sep=7.41". The closest Genie
source has ra= 314.6981 dec= 41.7770 mag=15.66 sep=7.41".
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
131 seconds after the BAT trigger. There is a candidate afterglow in the
rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 20:58:47.53 = 314.69805
DEC(J2000) = +41:46:37.2 = 41.77701
with a 90%-confidence error radius of about 0.75 arc sec. This position is 7.41
arc sec. from the center of the XRT error circle. The estimated magnitude is
15.66 with a 1-sigma error of about 0.14. No correction has been made for the
large, but uncertain, extinction expected.
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?
575370171 131 U srclist found no candidates.
575370171 131 U image found no candidates.
List afterglow candidates for other finding charts.
------- Tokens for Quick GCN -------
CATALOG_TYPE: IMAGE
FILTER: u
GRB_DEC: 41.77720
GRB_ERROR: 14.75
GRB_RA: 314.69530
IMAGE_START_TIME: 09:02:46
MAGNITUDE: 16.3
MAG_ERROR: 3.0
MESSAGE_TYPE: NACK
SOURCE: XRT