GRB 060717

T. Sakamoto (NASA/ORAU), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), S. Campana (INAF-OAB),
M. Capalbi (ASDC), M.L. Conciatore (ASDC), C. Gronwall (PSU),
H. A. Krimm (GSFC/USRA), K. M. McLean (LANL/UTD),
K. L. Page (U Leicester), D. M. Palmer (LANL), M. Perri (ASDC),
P. Romano (INAF-OAB) and L. Vetere (ASDC) report on behalf of the
Swift Team:

At 09:07:38 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 060717 (trigger=219646).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA,Dec 170.862, +28.948 {11h 23m 27s, +28d 56' 54"} (J2000)
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a single peak 
about 5 sec in duration with a peak count rate of 1000 counts/sec (15-350 keV). 

The XRT began taking data at 09:11:15 UT, 216 seconds after the BAT
trigger.  The XRT on-board centroid algorithm did not find a source in the
image, however analysis of TDRSS downlinked PC data reveals a faint point 
source at the following coordinates

   RA(J2000) =  11h 23m 21.9s
   Dec(J2000)= +28d 57' 05.4"

with an estimated uncertainty of 9 arcseconds radius (90% containment). 
This position lies 66 arcseconds from BAT localization. 

UVOT took a finding chart exposure of 73 seconds with the
White (160-650 nm) filter starting 221 seconds after the BAT trigger. 
No afterglow candidate has been found in the initial data products. 
Image catalog data are not available at this time. 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 extinction.

E.Sonoda, S.Maeno, M.Yamauchi
(University of Miyazaki)


"We have observed the field covering the error circle of
GRB060717 (GCN 5326
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 ) with the unfiltered CCD camera on
the 30-cm telescope at University of Miyazaki.
The observation was started 12:07:14 UT on Jul. 17.
After co-adding a set of 11 images (12:07:14 - 12:18:58 UT)
of 30 sec exposures, we have compared with the USNO A2.0 catalog.
Preliminary analysis shows there is no new source brighter
than 16.5 mag. "

Richard J. Cool (Arizona), Daniel J. Eisenstein (Arizona),
David W. Hogg (NYU), Michael R. Blanton (NYU), David
J. Schlegel (LBNL), J. Brinkmann (APO), Donald Q. Lamb
(Chicago), Donald P. Schneider (PSU), and Daniel E. Vanden
Berk (PSU) report:

The Sloan Digital Sky Survey (SDSS) imaged the field of
burst GRB060717 prior to the burst.  As these data should
be useful as a pre-burst comparison and for calibrating
photometry, we are supplying the images and photometry
measurements for this GRB field to the community.

Data from the SDSS, including 5 FITS images, 3 JPGS, and
3 files of photometry and astrometry, are being placed
at http://mizar.as.arizona.edu/~grb/public/GRB060717

We supply FITS images in each of the 5 SDSS bands of a
8'x8' region centered on the GRB position (ra=170.841
(11:23:21.8), dec=28.9150 (28:54:54.0); GCN 5326
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 ),
as well as 3 gri color-composite JPGs (with different
stretches). The units in the FITS images are nanomaggies
per pixel.  A pixel is 0.396 arcsec on a side. A nanomaggie
is a flux-density unit equal to 10^-9 of a magnitude
0 source or, to the extent that SDSS is an AB system,
3.631e-6 Jy.  The FITS images have WCS astrometric
information.

In the file GRB060717_sdss.calstar.dat, we report
photometry and astrometry of 136 bright stars (r<20.5)
within 15' of the burst location.  The magnitudes presented
in this file are asinh magnitudes as are standard in the
SDSS (Lupton 1999, AJ, 118, 1406). Beware that some of
these stars are not well-detected in the u-band; use the
errors and object flags to monitor data quality.

In the files GRB060717_sdss.objects_flux.dat and
GRB060717_sdss.objects_magnitudes.dat, we report photometry
of 842 objects detected within 6' of the GRB position.
We have removed saturated objects and objects with
model magnitudes fainter than 23.0 in the r-band.
The fluxes listed in GRB060717_sdss.objects_flux.dat
are in nanomaggies while the magnitudes listed in
GRB060717_sdss.objects_magnitudes.dat are asinh magnitudes.

All quantities reported are standard SDSS photometry,
meaning that they are very close to AB zeropoints
and magnitudes are quoted in asinh magnitudes.
Photometric zeropoints are known to about 2% rms.
None of the photometry is corrected for dust extinction.
The Schlegel, Finkbeiner, and Davis (1998) predictions
for this region are A_U=0.091 mag, A_g=0.067 mag, A_r =
0.048 mag, A_i=0.037 mag, and A_z=0.026 mag.

There are currently no objects within 6 arcminutes of the
GRB position in the SDSS spectroscopic database.


SDSS astrometry is generally better than 0.1 arcsecond
per coordinate.  Users requiring high precision astrometry
should take note that the SDSS astrometric system can
differ from other systems such as those used in other
notices; we have not checked the offsets in this region.

More detailed information pertaining to our SDSS GRB
releases can be found in our initial data release paper
(Cool et al. 2006, astro-ph/0601218).  See the SDSS DR4
documentation for more details: http://www.sdss.org/dr4.

These data have been reduced using a slightly different
pipeline than that used for SDSS public data releases.
We cannot guarantee that the values here will exactly match
those in the data release in which these data are included.
In particular, we expect the photometric calibrations to
differ by of order 0.01 mag.

This note may be cited, but please also cite the SDSS data
release paper, Adelman-McCarthy et al. (2006, ApJS, in
press, astro-ph/0507711), when using the data or referring
to the technical documentation.

C. Markwardt (GSFC/UMD), L. Barbier (GSFC), S. D. Barthelmy (GSFC),
J. Cummings (GSFC/ORAU), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hullinger (BYU-Idaho), H. Krimm (GSFC/USRA), M. Koss (GSFC/UMD),
J. Norris (GSFC), D. Palmer (LANL), A. Parsons (GSFC),
T. Sakamoto (GSFC/ORAU), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC)
on behalf of the Swift-BAT team:

Using the data set from T-119 to T+183 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 060717 (trigger #219646)
(Sakamoto, et al., GCN Circ. 5326
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 ).  The BAT ground-calculated position is
RA,Dec = 170.851,+28.970 deg {11h 23m 24.2s,+28d 58' 12.5"} (J2000)
+- 2.7 arcmin, (radius, sys+stat, 90% containment).  The partial coding was 99%.

The mask-weighted light curve shows a single peak which is most prominent in the
15-50 keV energy band and not detectable above 100 keV.  T90 (15-350 keV) is
3.0 +- 1 sec (estimated error including systematics).  The standard Norris
lag analysis for this burst is 250 +/- 250 msec (15-25 to 50-100 keV
energy bands for the CCF).  This plus the soft spectrum indicate that this
is not a short GRB.

The time-averaged spectrum from T-0.2 to T+2.8 is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.72 +- 0.38.  The fluence in the 15-150 keV band is 6.5 +- 1.6 x 10^-8 erg/cm2.
The 1-sec peak photon flux measured from T+0.78 sec in the 15-150 keV
band is 0.5 +- 0.1 ph/cm2/sec.  All the quoted errors are at the 90%
confidence level.

M. Capalbi, M. Perri (ASDC), D.N. Burrows (PSU) report on behalf
of the Swift XRT team:

We have analysed the first 3 orbits of XRT data for GRB 060717
(trigger #219646, Sakamoto et al., GCN 5326
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 ). A ~2.6ks PC mode
image reveals a faint (30 photons), fading X-ray source at the following
coordinates:

RA(J2000) =   11h 23m 21.74s
Dec(J2000) = +28d 57' 03.2"

with an estimated uncertainty of 5.3 arcseconds (90% containment).
This position lies 3 arcseconds from the XRT position given in GCN 5326
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and 76.5
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  arcseconds from the center of the refined BAT error circle
(Markwardt et al., GCN 5330
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 ).

This circular is an official product of the Swift XRT Team.

A. Cucchiara (PSU), P. Brown on behalf of the Swift/UVOT
team:

The Swift UVOT began taking data on the field of GRB 060717
222 s after the BAT trigger (Sakamoto et al. 2006,
GCN Circular 5326
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 ).  No new source, relative to the DSS, is seen
inside the refined XRT error circle (Capalbi et al. GCN 5331
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 )
The 3-sigma upper limits for the first finding chart
and the coadded images are listed below.

Finding chart:

         Midpoint   Exposure
Filter  Time (s)     (s)          Mag
White     272        100       19.57  3-sigma upper limit (160-650 nm)

Coadded images:

Filter     T_start(s)    T_stop(s)    EXPOSURE (s)    Mag   
White    222             10309               1241              20.85  UL
V          203             11899               1079              19.62  UL
B          4436           16062               1298              20.66  UL
U          4231             5862                400              19.83  UL
UVW1     4027         5659                393              19.33  UL
UVM2     3822         5453                400              19.25  UL
UVW2     4845       11215               1099              20.51  UL  

T_start and T_stop are estimated from the time of the burst.
These upper limits have not been corrected for the estimated Galactic
reddening of E_{B-V} = 0.064 mag (Schlegel et al. 1998).

A. Stefanescu, G. Kanbach, S. Duscha, F. Schrey, M. Muehlegger,
N.Prymak, H. Steinle (MPE Garching) of the OPTIMA-Burst team report from 
the 1.3m Skinakas Observatory(University of Crete, Heraklion, Greece):

We observed the position of the refined XRT errorcircle (GCN 5331
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 , 
Capalbi et al.) on 2006-07-17 at 18:55 UT (9:48h post burst). We do not 
detect a counterpart candidate in our 3x600s white light exposures 
brighter than 21mag.

Pall Jakobsson (U. Hertfordshire), Johan P.U. Fynbo,
Jens Hjorth (DARK, NBI), Tine B. Nielsen and Karianne
Holhjem (NOT, La Palma) report:

We observed the afterglow position of GRB 060717 (Sakamoto
et al., GCN 5326
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 ) on July 17.906 (12.5 hr post-burst) in
R-band and on July 17.922 (12.9 hr post-burst) in i-band with
ALFOSC on the Nordic Optical Telescope. Inside the revised
XRT error circle (Capalbi et al., GCN 5331
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 ), we find no
evidence for any sources. The limiting magnitudes of our
observations are R > 23.8 and i > 22.7.

The corresponding upper limit on beta_OX is 0.42, rendering
the burst dark according to the definition proposed by
Jakobsson et al. (2004, ApJ, 617, L21).

M. Capalbi, M. Perri (ASDC), D.N. Burrows (PSU),
T. Sakamoto (NASA/ORAU) report on behalf of the Swift XRT team:

We have analysed the first 8 orbits of XRT data from GRB 060717
(Sakamoto et al., GCN 5326
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 ). A Photon Counting mode image (11 ks)
provides a refined XRT position:

RA(J2000)  = 11h 23m 21.79s
Dec(J2000) = +28d 57m 03.3s

with an uncertainty of 4.5 arcsec (90% containment). This position is 0.7
arcsec away from the XRT position quoted in Capalbi et al. (GCN 5331
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 ).

The 0.3-10 keV X-ray light curve shows a power law decline with a
decay index of -0.9 � 0.2.

There are only 56 counts, insufficient for spectral analysis. Assuming
a photon index of 2.0 and the Galactic value for the column density
(1.4e20 cm^-2), the estimated unabsorbed source flux at T+24h is
about 3e-14 erg cm^-2 s^-1.

This circular is an official product of the Swift XRT Team.

I. Asfandyarov (MAO), A. Pozanenko (IKI), M. Ibrahimov (MAO) on behalf of
larger GRB follow up collaboration report:

We observed the field of GRB060717 (Sakamoto et al., GCN 5326
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 ) with 1.5 m
telescope of Maidanak Astronomical Observatory (MAO)  on July 17, (UT)
16:02 - 16:19. We do no detect optical sources in R-band within refined XRT
error box (Capalbi et al., GCN  5338
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 ). Based on USNO A2.0 we estimate
limiting (3 sigma) magnitude of a combined image:

Mid time T0+ (hrs), Exposure, R_lim

7.05                840 sec   20.9

The message may be cited.