GRB 060213

V. Pal'shin, S. Golenetskii, R. Aptekar, E. Mazets, and D. Frederiks 
on behalf of the Konus-Wind team,

K. Hurley and T. Cline on behalf of the Ulysses, Mars Odyssey,
and Konus GRB teams,

I. Mitrofanov, A. Kozyrev, M. Litvak, A. Sanin, V. Tret'yakov and
A. Parshukov, on behalf of the HEND-Odyssey GRB team,

W. Boynton, C. Fellows, K. Harshman, C. Shinohara and R. Starr, on
behalf of the GRS-Odyssey GRB team,

S. Barthelmy, J. Cummings, N. Gehrels, and H. Krimm, on behalf of 
the Swift-BAT team,

A. von Kienlin, G. Lichti, A. Rau, D. Gotz, and S. Mereghetti,
on behalf of the INTEGRAL GRB team,

and K.Yamaoka, Y.Fukazawa, T.Takahashi, M.Tashiro, Y. Terada,
T.Murakami, and K.Makishima on behalf of the Suzaku WAM team

report on GRB 060213.


GRB 060213 occurred at about 13:11:09 UT.  It was observed by Konus, 
INTEGRAL (SPI-ACS), Suzaku (WAM), Mars Odyssey (HEND and GRS), and 
Swift (BAT).  Ulysses was off, and the burst was outside of the field 
of view of Swift-BAT, so it was not imaged.

It was a bright, single FRED with a duration ~ 60 sec.  The position 
has been triangulated to RA, Dec 141.60, -9.15 (J2000).  The corners 
of the 3 sigma error box are:

141.46,  -9.45
141.50,  -9.43
141.74,  -8.85
141.70,  -8.87

The area of this error box is ~57 sq. arcmin.

Konus-Wind spectral analysis is in progress.  Preliminary analysis 
indicates that Epeak was ~1 MeV.

S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and
T. Cline on behalf of the Konus-Wind team report:

The long hard GRB 060213, which was localized by IPN (Pal'shin et al., 
GCN 4762
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 ), triggered Konus-Wind at T0=47469.517 s UT (13:11:09.517).

As observed by Konus-Wind it had a duration of ~60 s,
fluence 1.599(-0.082, +0.066)x10^-4 erg/cm2,
and the 16-ms peak flux measured from T0+0.320 s
6.95(-1.84, +1.82)x10^-5  erg/cm2/s
(both in the 20 keV - 4 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+56.832 s) is well fitted (in the 20 keV - 4 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ E^(-alpha)*exp(-E*(2-alpha)/Ep)
with alpha = 0.834(-0.045, +0.043)
and Ep = 1061 (-43, 83) keV (chi2 = 79.5/71 dof).

The spectrum integrated over the 1.024-s maximum
(accumulated from T0+0.256 s)
is well fitted in the same energy range
by  a power law with exponential cutoff model
with alpha = 0.458(-0.074, 0.070)
and Ep = 1230 (-94, 104) keV (chi2 = 61.5/61 dof)

All the quoted errors are at the 90% confidence level.

This is one of the most intense GRBs detected by Konus-Wind so far.

The Konus-Wind light curve of this GRB will be available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB060213_T47469/

V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy,
A.Krylov, G.Borisov, A.Sankovich, G.Antipov, V.Vladimirov
M.Sinitsin, P.Gritsyk

Sternberg Astronomical Institute, Moscow Union 'Optic'
MASTER  robotic system (http://observ.pereplet.ru) responded to GRB060213
  (GRB_TIME is 2006-02-13 13:11:09 UT).
First image was at 2006-02-15 20:28:35 UT, 2 days 07:17:25.45
after the GRB time.
Our upper limit on the sum of 10 images is about  17.0 m (there is a 
moonlight). Robot doesn't find OT-candidate in error box brighter then
17.0m.

Our unfiltered images were calibrated relative to USNO A2.0 (0.8R + 0.2B).
The JPG-image will be  available at
http://observ.pereplet.ru/images/GRB060213/img/i12.jpg
The reduction will be  continued.
This work is supported by RFFI  04-02-16411 grant.
This message can be cited.
Mailto: lipunov@sai.msu.ru

V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy,
A.Krylov, G.Borisov, A.Sankovich, G.Antipov, V.Vladimirov
M.Sinitsin, P.Gritsyk

Sternberg Astronomical Institute, Moscow Union 'Optic'
MASTER  robotic system (http://observ.pereplet.ru) responded to GRB060213
  (GRB_TIME is 2006-02-13 13:11:09 UT).
First image was at 2006-02-15 20:28:35 UT, 2 days 07:17:25.45
after the GRB time (GCN 4765
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 ). The exposition is 30 sec for all images.
Our upper limit on the sum of 20 images is about  17.5 m (there is a 
moonlight). Robot doesn't find OT-candidate in error box.

Our unfiltered images were calibrated relative to USNO A2.0 (0.8R + 0.2B).
The JPG-image will be  available at
http://observ.pereplet.ru/images/GRB060213/img/i12_sum20.jpg.jpg
This work is supported by RFFI  04-02-16411 grant.
This message can be cited.
Mailto: lipunov@sai.msu.ru

A. Pelangeon and J-L. Atteia (LATT-OMP) report:

We have used the spectral parameters provided by Golenetskii et al.
(GCNC 4763) to compute the spectral pseudo-redshift of GRB 060213
localized by the IPN (Pal'shin et al., GCNC 4762).

We find a pseudo-redshift: pz = 3.5 +/- 0.35

D. C. Morris (PSU), J. A. Kennea (PSU), C. Pagani (PSU) report on behalf 
of the Swift XRT Team:

Swift responded to the IPN trigger of GRB060213 (Pal'shin et al., GCN 
4762
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 ) and has observed the entire IPN error polygon with the XRT during 
observations spanning T+174ks to T+285ks. We have analyzed the entire 
XRT ground-linked dataset. In 9ks of data we find a single, faint, 
uncatalogued source within the IPN localization at the following position:

RA(J2000): 09 26 24.5
Dec(J2000): -09 06 58.5

with an estimated uncertainty of 10 arcseconds (90% containment). The 
source is detected at 2.6 sigma and the flux at T+3days from the 
GRB060213 trigger is 2e-13+/-5e-14 ergs/cm2/s. We note that this source 
does not show evidence of fading during the 1.25 day window of XRT 
observations and appears slightly extended to the east, which both 
suggest the possibility that it may be a faint serendipitous object and 
not the GRB afterglow. However, we also note that it is not uncommon for 
a GRB afterglow at this late stage to have a fairly flat lightcurve 
consistent with the observed counting statistics, and we therefore 
cannot rule this out as an afterglow candidate.  Further observations 
will be required to determine conclusively whether this source is fading.

No other point source is detected above a limiting flux of 1e-13 
ergs/cm2/s anywhere in the IPN localization, or in the broader 
surrounding region covered by the XRT field of view during the 
observations.

No further observations are planned for at least the next four days; 
however, we tentatively plan further observations in approximately a 
week to determine whether the source is fading.

The XRT image of the field can be viewed at 
http://www.swift.psu.edu/images/GRB060213.jpg

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

S. Guziy, M. Jelinek, A. J. Castro-Tirado,
S. B. Pandey, A. de Ugarte Postigo, S. Vitek,
J. Gorosabel (IAA-CSIC, Granada), K. Viironen
(IAC La Laguna), J. A. Caballero (IAC and ING
of Telescopes, La Palma) and L. Sabin (ING)
report:

"Following the detection by the IPN of GRB 060213 (Pal'shin et
al. GCN Circ. 4762
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 ) we obtained 3 x 180s images with the 2.5m
INT (+WFC camera) at La Palma starting on 16.05 Feb UT (i.e.
60 hr after the event). 

In the 10" XRT errorbox given by Morris et al. (GCN Circ.
4770
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 ) the comparison of the stacked image with the DSS-2
reveals a new point-like source with R about 21.5
(preliminary, against usnob) at 

RA = 09 26 24.14 Dec = -09 06 57.4 (+/- 0".3, J2000).

We suggest that this is the optical afterglow to GRB 060213.
Further observations are planned."

This message can be quoted.

M. De Pasquale (MSSL-UCL), D. Morris (PSU) and P. Roming (PSU)
on the behalf of the Swift UVOT/team:

  The Swift/UVOT began taking data on the field of GRB 060213
at 13:35:41 UT on 2006-02-15, 48.41 hours after the GRB
(Pal'shin et al. GCN 4762
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 ).

The UVOT field does not cover the whole IPN error box, but it
encompasses the field of the uncatalogued source detected
by the XRT (Morris et al. GCN 4770
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 ). No optical afterglow
candidate is detected in the summed images of each of the
UVOT filters down to the following 3-sigma magnitude
upper limits:

Filter     T_range (sec)    Exp(sec)           3 sigma u.l.

  V        180203 - 187038     1020                 20.1

  B        185073 - 185982     849                  21

  UW1      175186 - 176088     878                  20.4

  UM2      174272 - 180401    1620                  20.7

  UW2      179290 - 186897    1705                  21.1

The quoted values have not been corrected for Galactic extinction.

M. Jelínek. S. Guziy (IAA-CSIC Granada), K. Viironen
(IAC La Laguna), L. Sabin (ING of Telescopes,
La Palma) and J. A. Caballero (IAC and ING),
on behalf of larger collaboration, report:


"We have performed a second epoch observation of the field including
the optical afterglow candidate (cf. Guziy et al. GCN 4771
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 ) to GRB
060213. On the stacked 5 x 180s frame taken on Feb 17.95 UT, we cannot
confirm a decline in brightness and conclude that the aforementioned
object is probably a normal star with R = 21.6 +/- 0.1.

We note however, that the only other object that lies within the
Swift/XRT error box (Morris et al. GCNC 4770) down to R = 23.0
limiting magnitude, is at coordinates (J2000) RA = 09h26m24.27s,
Dec= -09o06'54".7 (i.e. 5" from the XRT center) and appears to be
a relatively bright galaxy (R = 20.0 +/- 0.1 within our 1" aperture)
catalogued in GSC2 as S12101311196. If this galaxy is unrelated to
GRB 060213, spectroscopic observations will be needed to discern
whether this is an active galaxy originating the X-ray emission
detected by SWIFT."

This message can be quoted.