image overlap message for exposure 2 of trigger 828672


uvot_overlap.pl vrs. 2010-12-20b fem started at 180425d09h09m14s618178usUT

The observation of trigger 828672 started 2018-04-25T06:51:44.3
Examining file ./828672_g322_uvot_sky_image.fits
The exposure ID is 546331904
The exposure time is 249.935 (seconds)
The filter is U.

The uvot region is centered at (64.4473,-32.9522) with a roll angle of 321.4
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 (64.4690,-32.9560) with a radius of 3.000 arc min
This is 1.116 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 (64.4516,-32.9522) with a radius of 0.030 arc min
This is 0.215 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 2 of trigger 828672


find_uvot_ag.pl vrs. 2017-02-17 fem started at 180425d09h09m25s078136usUT

Observation start time is 2018-04-25T06:51:44.3
Examining file ./828672_g322_uvot_catalog_image.fits
The exposure ID is 546331904
The exposure is 249.935 sec.
The bin size is 2 pixels
The filter is U
There are 4 detected source(s) for 828672_g322
Aspect correction adds -0.00057 degrees (-0.138 sec of time = -1.73 arc sec) to RA
Aspect correction adds 0.00038 degrees ( 1.39 arcsec) to Dec
Total aspect correction is 2.22 arcsec
Star catalogs centered at 64.4472 , -32.9555 with radius 2.23 arc min.
n_usno: 53 n_gsc: 42
Bright star catalog has no entries brighter than 12 mag
Mean distance difference (CAT_DELTA) for 5 matched entries is 0.625" for 828672_g322
Mean and std. dev of mag. difference (MAG_DELTA) are 0.048 and 1.940 for 828672_g322
Found 0 entries without IDs and 0 entries that are acceptable afterglow candidates for 828672_g322.
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=64.4690 (04:17:52.56) DEC=-32.9560 (-32:57:21.6)
XRT distances are from RA=64.4516 (04:17:48.38) DEC=-32.9522 (-32:57:07.8)

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

List UVOT sources within 10" of the XRT position:
There are 16543.523 counts in the bkg source region of 6202.0000 pixels.
Rate in bkg region from 0 to 45 arcsec is 2.667 counts/pixel (5-sig UL in 4" is 19.93 mag) for 828672_g322
There are 511.98834 counts in the xrt source region of 199.00000 pixels.
Rate in xrt region with 8 arcsec radius is 2.573 counts/pixel for 828672_g322
There are 3251.3740 counts in the xrt_bkg source region of 1246.0000 pixels.
Rate in xrt_bkg region from 15 to 25 arcsec is 2.609 counts/pixel (5-sig UL in 4" is 19.94 mag) for 828672_g322

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 20.49, XRT distances < 5",
are > ~(80 - 10*(mag-6))" from any bright star, and have had duplicates removed.

SUMMARY: 0 good candidate(s) found.



Region file: 828672_546331904_180425d09h09m25s078136usUT_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(64.4473,-32.9522,45")
fk5;-circle(64.4568928485432,-32.9598102292917,6")



Region file: 828672_546331904_180425d09h09m25s078136usUT_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(64.45158,-32.95217,8")



Region file: 828672_546331904_180425d09h09m25s078136usUT_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(64.45158,-32.95217,25")
fk5;-circle(64.45158,-32.95217,15")



image paragraph message for exposure 2 of trigger 828672



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

In response to GRB180425 (Swift/BAT trigger 828672) at 06:46:21 UT,

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

UVOT took a finding chart exposure of 250 seconds with the U filter starting
301 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
0.03.

------- notes for trigger 828672 ------
uvot_gcn_auto.pl vrs. 2016-09-07 fem at 180425d09h09m27s696195usUT
Command line: /Home/eud/uvot_tdrss/perl/uvot_gcn_auto.pl -trig=828672
-expid=546331904 -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/828672/
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 546331904.27186 or about 2018:115:06:51:39 UT

Found 318 stars in largest star catalog for srclist region. The stars will
eliminate afterglows from about 6% of the srclist region. Found 32 sources in
srclist catalog. Found 17 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 4 source(s) in Genie image catalog. 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 20.49 mag. Found 49 stars in largest star catalog for
Genie image region. The stars will eliminate afterglows from about 6% of the
Genie image region.

Genie image analysis:
Found 16543.5 counts in the large background region of 6202.0 pixels or a rate
of 2.667 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 19.97 mag. for a
4-arcsec aperture.
Found 512.0 counts in the XRT position region of 199.0 pixels or a rate of
2.573 counts/pixel in a radius of 8.0 arcsec. The net count rate (using local
background region) at the XRT position is -0.029 +/- 0.098 (1-sigma) cps. The
3-sigma UL at the XRT position is 0.293 cps or 19.71 mag. The closest srclist
source has ra= 64.4568 dec= -32.9599 mag=18.80 sep=31.86". The closest Genie
source has ra= 64.4569 dec= -32.9598 mag=18.34 sep=31.84".

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?
546331904  301 U srclist found no candidates.
546331904  301 U image found no candidates.
List afterglow candidates for other finding charts.
546331690   87 WHITE srclist found no candidates.
546331690   87 WHITE image found no candidates.
546332481  878 WHITE srclist found no candidates.
546332481  878 WHITE image found no candidates.

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

CATALOG_TYPE: IMAGE
FILTER: u
GRB_DEC: -32.95217
GRB_ERROR: 5
GRB_RA: 64.45158
IMAGE_START_TIME: 06:51:39
MAGNITUDE: 19.7
MAG_ERROR: 3.0
MESSAGE_TYPE: NACK
SOURCE: XRT