GRB 060124

S. T. Holland (GSFC/USRA), S. Barthelmy (GSFC), D. N. Burrows (PSU),
N. Gehrels (GSFC), S. Hunsberger (PSU), J. Kennea (PSU),
V. La Parola (INAF-IASF/Palermo), C. Markwardt (GSFC/UMD),
K. Page (U Leicester), D. Palmer (LANL), and
T. Sakamoto (GSFC) report on behalf of the Swift team:

At 15:54:52 UT, Swift-BAT triggered and located GRB 060124 (trigger=178750).
The spacecraft slewed immediately. The BAT on-board calculated location is
RA,Dec 77.043d,+69.709d {05h 08m 10s,+69d 42' 33"} (J2000), with an 
uncertainty
of 3 arcmin (radius, 90% containment, stat+sys).  The BAT light curve shows an
~30-sec duration with at least two peaks.  The peak count rate was ~1700 
counts/sec
(15-350 keV) at the trigger time.

XRT began observing the field at 15:56:38, 106 sec after the BAT trigger.
No source was found by the onboard centroiding algorithm.  The lightcurve has a
hint of a fading source, but more data are needed in order to assess the 
presence
of a source in the field.

No UVOT data are available at this time.

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

Sternberg Astronomical Institute, Moscow Union 'Optic'
MASTER  robotic system (http://observ.pereplet.ru) responded to
Swift GRB060124 (GRB_TIME is  15:54:52UT, GCNCirc 4570) under the bad 
weather conditions.
The first image was at 2006-01-24 17:30:07 UT, 96 min after the GRB time 
(without socket alert information).
The unfiltered image is calibrated relative to USNO A2.0 (0.8 R + 0.2 B).
The robot not find OT-candidate in error box.
Our upper limit is about  14.4 m.
The reduction is continuing.
This work is supported by RFFI  04-02-16411 grant.
This message can be cited.
Mailto: lipunov@sai.msu.ru

D. A. Kann reports on behalf of the Tautenburg GRB Team:

I observed the field of Swift GRB 060124 (S. T. Holland et al., GCN 4570
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 ) with the 
Tautenburg 1.34m Schmidt telescope equipped with the 2k x 2k Schmidt CCD 
camera. Observations were obtained under good conditions and low airmass, 
beginning at 16:54:54 UT, i.e. one hour after the burst, in twilight. I obtained 6 x 180 
sec frames each in V, Rc and Ic.

A visual inspection of the Swift BAT error circle in comparison to the DSS 2 infrared 
plate reveals no obvious afterglow candidate to the following rough limits:

t (mid) UT	Filter	Limit

0.0427		Ic	> 17
0.0559		Ic	> 18
0.0587		Rc	> 20
0.0746 		V	> 20

These values are not corrected for the moderate Galactic extinction (E(B-V)=0.135).

Further analysis is in progress.

This message may be cited.

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


"We have observed the field covering the error circle of
GRB060124 (GCN 4570
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 ) with the unfiltered CCD camera on
the 30-cm telescope at University of Miyazaki.
The observation was started 16:21:08 UT on Jan.24.
After co-adding a set of 23 images (16:21:08 - 16:59:35 UT)
of 30 sec exposures, we have compared with the USNO A2.0 catalog.
Preliminary analysis shows there is no new source brighter
than 15.7 mag."

D. A. Kann reports on behalf of the Tautenburg GRB team:

Further inspection of the Tautenburg images (Kann, GCN 4574
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 ) reveals an optical 
afterglow candidate within a preliminary XRT error circle (E. Rol, private 
communication) at

R.A. 05 08 25.5
Dec: +69 44 26

with an error of 2" in comparison with the DSS infrared plate.

The candidate is detected in all single frames and does not seem to fade upon 
visual inspection. On the other hand, the object does not move over one hour of 
observation.

This message may be cited.

V. Mangano, G. Cusumano, V. La Parola, T. Mineo (INAF-IASFPA),
D.N. Burrows (PSU) on behalf of the Swift XRT team:

We have analyzed the first orbit of XRT data from GRB 060124
(trigger 178750; Holland et al., GCN 4570
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 ).
The observation consists of an 865 s exposure in Windowed Timing
mode interruped by a 15 s exposure in Photon Counting mode because
of mode switching.

The Photon Counting mode image provides a source XRT position:

RA(J2000) = 05h 08m 27.27s
Dec(J2000) = +69d 44' 25.7"

with an uncertainty of 5.6 arcsec (90% containment). This position includes
the latest XRT boresight correction. This position is 2.4 arcmin from the
BAT position and 9 arcseconds from the candidate optical counterpart found
by Kann (GCN 4577
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 ).

The Windowed Timing light curve of this source shows an initial flat 
behaviour
followed by three bright flares after the first 100 s of observation.
A more detailed analysis will be distributed later.

D. A. Kann, M. Henze & U. Laux report on behalf of the Tautenburg GRB team:

We reobserved the candidate optical afterglow (D. A. Kann, GCN 4577
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 ) of Swift 
GRB 060124 (S. T. Holland et al., GCN 4570
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 ) with the Tautenburg 1.34m Schmidt 
telescope under worsening weather conditions (thin haze) in V, Rc and Ic for 300 
sec each, starting at about 20:35 UT.

The object has significantly faded, being near the detection limit of the images. We 
thus confirm the afterglow nature of the candidate we reported earlier.

This message may be cited.

GRB 060124: Swift/UVOT Observation

S. T. Holland (GSFC/USRA), P. Smith (UCL-MSSL), H. Huckle (UCL-MSSL),
and N. Gehrels (GSFC) on behalf of the Swift/UVOT team

      The optical transient detected by Kann (2006, GCN Circular 4577
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 )
is detected in the Swift/UVOT V-band exposures taken 184 and 629 s
after the BAT Trigger (Holland et al., 2006, GCN Circular 4570
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 ).  The
V-band magnitudes, uncorrected for Galactic extinction are.

Start UTC            EXPOSURE  Filter   Mag  Err    t-t0
                        (s)                           (s)
2006-01-24T15:56:39    153      V      17.08 0.08    184
2006-01-24T15:59:18    725      V      16.88 0.03    629

      The Galactic reddening in the direction of the transient is
E_{B-V) = 0.14 mag.  The Harvard Minor Planet Checker shows no known
minor planets at the location of the optical transient.

Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:

We imaged the field of GRB 060124 detected by SWIFT
(trigger 178750) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

First image was acquired 1.98h after the GCN trigger.
The field elevation increased from
51 degrees above horizon and weather conditions
were good.

We do not detected an OT source.
According to the limiting magnitude: R>18.5

Magnitudes were estimated with the nearby USNO-A2 stars

This message may be cited.

E. Fenimore (LANL), L. Barbier (GSFC), S. Barthelmy (GSFC), 
J. Cummings (GSFC/NRC), N. Gehrels (GSFC), D. Hullinger (GSFC/UMD),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), T. McMahon (Langston U.), 
D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/NRC), 
G. Sato (ISAS), J. Tueller (GSFC), N. White (GSFC) 
on behalf of the Swift-BAT team:

Using the data set from T-50.0 to T+1000.0 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 060124 (trigger #178750) 
(Holland, et al., GCN 4570
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 ).  The BAT ground-calculated position is 
(RA,Dec) = 77.128, 69.724  deg {5h 8m 30.6s, 69d 43' 27.9"} (J2000)
+- 1.6 arcmin, (radius, sys+stat, 90% containment).  The partial coding 
was 62%.

The BAT mask-weighted lightcurve has a precursor from T-3 to T+13 sec, 
then three major peaks: T+520 to T+550 sec, T+560 to T+580 sec (with the 
largest flux), and T+690 to T+710 sec. Thus the total duration is one of 
the longest recorded by BATSE or Swift. 
 
The spectrum of the main peaks appears slightly harder than the precursor, 
but so far we have detailed data for the precursor only.  The spectrum of 
the precursor from T-1.2 to T+13.2 is best fit by a simple power-law model 
with a photon index of 1.89 +- 0.19.  The fluence of the precursor emission 
in the 15-150 keV band is (4.6 +- 0.5) x 10^-07 erg/cm2. The peak flux in 
the 15-150 keV band was about 4.5 +- 0.5 counts/cm2/sec at T+570.  

We have made a preliminary estimate of the total fluence in the BAT
energy range for this burst by scaling the fluence of the precursor 
by the mask-weighted counts ratio between the entire burst and the 
precursor.  This estimated total fluence is ~7 x 10^-6 erg/cm2 in the 
15-150 keV band.

N. Masetti, E. Palazzi, E. Maiorano (INAF-IASF, Bologna), 
E. Pian (INAF - Astron. Obs. of Trieste), E. Giro 
(INAF - Astron. Obs. of Asiago), C. Bonoli (INAF - Astron. 
Obs. of Padova) and D. Malesani (SISSA, Trieste), 
on behalf of a larger Italian collaboration, report:

"We have obtained R-band imaging and an optical spectrum of 
the OT (Kann, GCN 4577
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 ) of GRB060124 (Holland et al. GCN 4570
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 ; 
Mangano et al., GCN 4578
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 ) with the 1.82-m "Copernico" telescope 
(plus AFOSC) of the Astronomical Observatory of Asiago (Italy).
The seeing was ~2.5 arcsec during the observations.

The R-band observation started on January 24.970 UT, 
i.e. 0.31 days after the GRB, and lasted 600 s.
The OT was well detected; we measure for it a magnitude 
R = 18.5 +- 0.1 with respect to USNO-A2.0 star U1575_02242799,
which has coordinates (J2000) RA = 05 08 31.05, 
Dec = +69 44 27.9 and magnitude R = 17.3.

The 1-hour spectrum, acquired starting on January 24.917 UT,
is characterized by a smooth and basically featureless
continuum. No emission lines are detected; absorption 
features are possibly present, but their low S/N prevents 
us to confirm their reality.

This message is citeable."

C.K Lu, Y. Qiu (BAO), Y.Q. Lou (THCA) 
Y. Urata (RIKEN), K-Y Huang (NCU) on behalf of EAFON report:

GRB 060124 : Optical observation at Xinglong and Kiso 

"We started R and I band imaging observation of GRB 060124 field at
16:21 (UT) using 0.8-m telescope at Xinglong observatory, China.  The
OT reported by (Kann # 4577) was detected clearly at RA = 05:08:25.9
Dec +69:44:27.

   The I band image is available at

     http://cosmic.riken.jp/grb/eafon/GRB060124_Xinglong_Iband.jpg

   Based on our preliminary R and I band photometry for Xinglong data,
the OT light curve do not show clear decay in our observational phase.

   We have also checked R-band data obtained under bad seeing
condition at Kiso observatory (Tomita et al. #4575). Due to
contamination from nearby bright star (USNOB: 1597.0077413), it is
hard to identify the OT by visual inspection. However, we also found
the OT in Kiso R band images."

This message may be cited.

Kuntal Misra (ARIES, Nainital) on behalf of a larger Indian GRB 
collaboration

We observed the field of GRB 060124 (SWIFT trigger 178750; GCN 4570
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 )
with the 104-cm Telescope at ARIES, Nainital in Rc band on
January 24.7016 UT under good sky conditions. The OT is well detected in 
our single image of 300 sec exposure at a magnitude of ~ 17, one hour 
after the burst, in comparison to 4 nearby USNO-A2.0 stars.

This message may be cited.

A. Kong (MIT)

We have analyzed a follow-up XRT observation of GRB 060124 taken 9.5 hours
after the first BAT detection (Holland et al. GCN 4570
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 ). The
observation lasted for 12.6 ksec and the effective Photon Counting mode
exposure time is 4.8 ksec. The X-ray afterglow (Mangano et al. GCN 4578
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 )
is clearly detected with a count rate of 0.16 c/s. The refined position is

R.A.(J2000)  =  05h 08m 26.11s
Dec. (J2000) = +69d 44m 26.9s

with an uncertainty of 3.6 arcsec (90% containment). This position
includes the latest XRT boresight correction. The refined position is
6.1 arcsec from the first XRT observation (Mangano et al. GCN 4578
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 ) and
1 arcmin from the refined BAT observation (Fenimore GCN 4586
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 ).

The time averaged X-ray spectrum can be well fitted with an absorbed
power-law with a photon index of 2.1+/-0.2 (90% confidence level) and a
column density of (2.0+/-0.6)e21 cm^-2, slightly higher than the
Galactic value (9.3e20 cm-2). The time averaged unabsorbed 0.5-10 keV flux
is 9.3e-12 ergs cm^-2 s^-1.

N. Mirabal (U. Michigan) and J. P. Halpern (Columbia U.) report for the
MDM GRB follow-up team:

"We have obtained a low-resolution spectrum of the afterglow of
GRB 060124 using the MDM 2.4m telescope and Boller & Chivens (CCDS)
spectrograph.  The observations consist of three 30-minute spectra
beginning on Jan 25.13.  Preliminary analysis reveals one significant
absorption feature, possibly a doublet, at 5105 A.  Assuming that this
corresponds to Mg II 2795,2802, the inferred redshift (or lower limit)
is z=0.82.  Alternatively, if this feature is C IV 1548,1550, then
z=2.30, and a marginally significant absorption feature that we see
at 4008 A could be Lyman alpha.  Independent confirmation of these
features is required."

S. B. Cenko (Caltech), E. Berger (Carnegie Observatories) and J. Cohen
(Caltech) report on behalf of a larger collaboration:

"We obtained two 1800 sec spectra of GRB 060124 (Holland et al., GCN 4570
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 )
with the Echellette Spectrograph and Imager (ESI) on the Keck 10-m
telescope starting on 2006 Jan. 25.23 UT.  We detect the broad absorption
feature detected by Mirabal and Halpern (GCN 4591
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 ), which is clearly a
doublet, and identify it as CIV 1548,1550 at z=2.297.  We also detect the
MgII 2796,2803 at the same redshift.  At this redshift and given a
fluence of about 7e-6 erg/cm^2 (Fenimore et al., GCN 4586
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 ) we find an
isotropic-equivalent gamma-ray energy of 8.9e52 erg."

J. X. Prochaska (UCO-Lick/UCSC),  R. Foley (UCB),
H. Tran (Keck), J. S. Bloom (UCB), H.-W. Chen (MIT),
report on behalf of the GRAASP collaboration:

"We have obtained Keck/LRIS spectra of the afterglow
of GRB 060124 starting at UT Jan 25 07:15 in polarimetry
mode under poor observing conditions.   We confirm the absorption
features at ~5105A reported by Mirabal et al. (GCN 4591
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 )
and rule out MgII on the basis of their separation.
Instead, we identify these features as CIV corresponding to
z=2.296 and we note a weak absorption feature consistent with
this redshift corresponding to AlII 1670.  We also
identify an absorption line at ~4000Ang consistent with
Lya absorption and indicating log N(HI) < 20.5.

Although we may also detect a weak feature consistent with
SiII 1526 at 5030Ang, this afterglow spectrum is notable
for exhibiting very weak low-ion features (e.g. non-detections
of FeII 1608, OI 1302, CII 1334) and relatively low HI column density.
In this respect the spectrum is similar to the afterglows
of GRB 050908 and GRB 021004.

Finally, we note a strong absorption feature at ~4840Ang
which could be MgII at z=0.73.

We thank the Keck Observatory for acquiring these observations
during Director's discretionary time.  The data will be made
publically available at www.graasp.org"

This message may be cited.

K. Torii (Osaka U.) reports on behalf of the ART collaboration:

 The error region of GRB 060124 (Holland et al., GCN 4570
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 ) was imaged
with the two Automated Response Telescopes in Toyonaka, Osaka, under
cloudy condition. The observations started before the arrivals of the
three major gamma-ray pulses (Fenimore et al. GCN 4586
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 ).

 The older 14 inch telescope, ART-3a, imaged the field starting at
15:55:59 UT (67 s after the BAT trigger). 60 s integrations were
repeated through each of the four linear polarizers (effective in
400-700 nm) in the filter wheel. The relative position angles between
the filters are 45 degrees. We did not detect any optical flare at the
position of the optical afterglow (Kann, GCN 4577
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 ; Kann, Henze, &
Laux, GCN 4579
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 ), in the first two frames, before the field was
completely clouded after ~15:58 UT (3.5 minutes after the trigger).

 A new 0.35m f/6 telescope, ART-3b, observed the field starting at
15:56:11 UT (79 s after the BAT trigger). Repeated 60 s integrations
were made through the standard Ic filter. We did not detect any
optical flare either, in the first two frames, and the later frames
were clouded.

 The following 3-sigma limits are derived for an optical transient
during the gamma-ray burst. The ART-3a and ART-3b magnitudes were
calculated with reference to USNO-B1.0 R2 and I magnitudes,
respectively.

-----------------------------
StartUT		Limits
=============================
15:55:59	>14.6R
15:56:11	>14.9I
=============================

B.C. Bhatt, D.K. Sahu, S. Srividya and N.K. Chakradhari (Indian Institute
of Astrophysics, Bangalore, India) communicate on behalf of a larger
Indian collaboration:

We observed the central 10x10 arcmin region of the error circle of the
Swift-BAT trigger(Holland et al. GCN 4570
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 ) in Bessell R filter with  the
2-m Himalayan Chandra Telescope, Hanle, India, starting from 2006 January
24.715 UT.

The OT of GRB 060124 detected by Kann (GCN 4577
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 ) and confirmed by Kann
et al (GCN 4579
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 ) was also detected in our individual frames of 600 s each.
Priliminary R band brightness was about 17 mag with respect to the nearby
USNO A2 stars. Further analysis is in progress.

This message may be cited.

T. Mineo (INAF-IASF), V. Mangano (INAF-IASF), V. La Parola 
(INAF-IASF),G. Cusumano (INAF-IASF), J. Kennea (PSU), S. T. Holland 
(GSFC/USRA), S.Hunsberger (PSU), J.Racusin (PSU), D. N. Burrows (PSU)
report on behalf of the Swift XRT team:

We have analyzed the Swift XRT data up to 0.55 days after the trigger
of GRB 060124 (Holland et al. GCN 4570
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 ) for a total exposure of about 11 
ks.
The refined coordinates of the X-ray afterglow are:

Ra(2000)   =  05 08 26.0 
Dec (2000) = +69 44 26.7

with an estimated uncertainty is of 3.6 arcseconds radius (90% 
containment).

This new position is 2.3 arcmin from BAT postion (Holland et al. GCN 
4570
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 ); 6.7 arcsec from the position given by Mangano et al. (GCN 4578
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  )
based on 15 s observation in PC mode, and 0.6" from the position
given by Kong et al (GCN 4590
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 ). Moreover the refined  coordinates are 2.7"
from the optical counterpart detected by Kann (GCN 4577
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 ).

The 0.2-10 keV light curve  shows intense flaring activity during the 
first orbit and a fading behaviour 10 ks after the trigger.
The light curve decay index in the interval 10-50 ks is -1.04+/-0.07.

The average spectrum  accumulated during the first orbit (from 100 s to 
1000 s after the trigger) is well fitted with a power law of photon 
index 1.40+/-0.01, absorbed at lower energies by a column of (0.172 � 
0.005)X10^22 cm^-2, higher than the galactic value (9.2X10^20 cm^-2) and 
a 0.2-10 keV unabsorbed flux  of 6.6E-09 ergs/cm^2/s. The average 
spectrum accumulated during the decay part of the light curve (from 11 
ks to 47 ks after the trigger) is well fitted with a power law with 
photon index 2.1+/-0.1 and a 0.2-10 keV  unabsorbed flux of 1.3E-11 
ergs/cm2/s. If the burst continues decaying at the current rate we 
estimate an XRT count rate of 0.05 counts/s at T+48hr, which corresponds 
to an  unabsorbed 0.2-10 keV flux of 3e-12 ergs/cm^2 s/1.

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

The most intense part of the very long GRB 060124 (Swift-BAT trigger 
#178750; Holland et al., GCN 4570
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 ; Fenimore et al., GCN 4586
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 )
triggered Konus-Wind at T0=57853.894 s UT (16:04:13.894).
The propagation delay from Swift to Wind is 3.0 s for this GRB, i.e., 
correcting for this factor, one sees that the K-W trigger time
corresponds to the Swift-BAT trigger time T0(S-B) + 558.9 s.

The Konus-Wind light curve, recorded prior T0 in the waiting mode, shows 
a weak precursor corresponding to the Swift-BAT trigger time,
no statistically significant emission in any K-W energy band from 
~T0(S-B)+20 s to ~T0(S-B)+340 s, resuming emission at ~T0(S-B)+340 s, a 
pulse at ~T0(S-B)+500 sec, the main double-peaked pulse from 
~T0(S-B)+550 s to ~T0(S-B)+590 s, weaker pulses up to T0(S-B)+800 s.
The burst light curve resembles the light curves of two previously 
detected very long bursts: GRB 041219a (Vestrand et al., Nature, 435, 
178 (2005)), and GRB 050820a (Golenetskii et al., GCN 3852
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 ).

The spectrum integrated over the most intense part of the burst
(from T0 to T0+24.832 s) is well fitted (in the 20 keV - 2 MeV range)
by GRBM (Band) model for which:
the low-energy photon index is alpha = -1.29(-0.11,+0.14),
the high energy photon index beta = -2.25(-0.88,+0.27),
the break energy E0 = 335(-120,+177) keV (chi2 = 66/61 dof).
The fitting by a power law with exponential cutoff model:
dN/dE ~ E^(-alpha)*exp(-E*(2-alpha)/Ep)
in the same energy range gives
alpha = 1.355(-0.075,+0.085)
and Ep = 285(-56,+63) keV (chi2 = 70/62 dof).

As observed by Konus-Wind the burst had
a peak flux measured from T0+11.440 sec on 64 msec time scale
2.66(-0.69,+0.74)x10^-6 erg/cm2/sec,
and a fluence of the most intense part of the burst
1.43(-0.24,+0.28)x10^-5 erg/cm2
(both in the 20 keV - 2 MeV energy range).

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

A preliminary estimation of the total burst fluence is ~2.80x10^-5 
erg/cm2/sec (20 keV - 2 MeV). This value was derived by scaling the 
fluence of the most intense part by the ratio between G2+G3 counts of 
entire burst and the most intense part. Such scaling is justified 
because G2/G3 hardness ratio is the same for the entire burst and the 
most intense part (G2: 30-300 keV, G3: 300-1160 keV).

Assuming z = 2.297 (Cenko, Berger, and Cohen, GCN 4592
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  ) and a standard 
cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.3, Omega_\Lambda = 
0.7, the isotropic energy release is E_iso ~3.4x10^53 erg,
the maximum luminosity is (L_iso)_max ~1.1x10^54 erg/s.

The Konus-Wind light curve of this GRB will be available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB060124_T57853/

GRB 060124: HETE detection and spectrum of the main peak

D. Lamb, G. Ricker, J-L. Atteia, N. Kawai, and S. Woosley, on behalf of
the HETE Science Team;

M. Arimoto, T. Donaghy, E. Fenimore, M. Galassi, C. Graziani,
N. Ishikawa, A. Kobayashi, J. Kotoku, M. Maetou, M. Matsuoka,
Y. Nakagawa, T. Sakamoto, R. Sato, T. Shimokawabe, Y. Shirasaki,
S. Sugita, M. Suzuki, T. Tamagawa, K. Tanaka, and A. Yoshida, on behalf
of the HETE WXM Team;

N. Butler, G. Crew, J. Doty, G. Prigozhin, R. Vanderspek,
J. Villasenor, J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga,
R. Manchanda, G. Pizzichini, and S. Gunasekera, on behalf of the HETE
Operations and HETE Optical-SXC Teams;

M. Boer, J-F Olive, A. Pelangeon, J-P Dezalay, and K. Hurley, on behalf
of the HETE FREGATE Team;

report:

The main peak of GRB 060124 (SWIFT trigger 178750, Fenimore et al. 
GCN 4586
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 ) triggered the FREGATE instrument on HETE at 16:04:09.5 UTC
(57849.5 SOD) on 24 January 2006 (HETE trigger 4012).  This time is 
557.7 s after the Swift trigger time.  The burst occurred at an angle
of about 60 degrees from the HETE boresight.  The main peak is the only
peak of this long GRB that was sufficiently bright to be seen by the
FREGATE instrument despite the large angle between the direction of the
source and the HETE boresight.

The burst locations provided by the Swift BAT and XRT instruments 
(Holland et al. GCN 4570
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 , Fenimore et al. GCN 4586
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 ) are within the 
FREGATE FOV but outside the WXM FOV.  Consequently, we have FREGATE
data, but not WXM data, for this event.

The main peak is detected in FREGATE in the 7-40, 7-80, and 30-400 keV
bands.  It is highly structured in time, exhibiting two maxima at 13s
and 23s after the HETE trigger time.

The spectrum in the 7-400 keV energy band is best fit with a power-law
times exponential spectrum.  The best-fit values and the 90% confidence 
intervals for the low-energy photon number index alpha and Epk are

alpha: 1.17 (-0.27/+0.23)
Epk:   305 (-118/+756) keV.

These parameter estimates are consistent with the KONUS results
reported by Golenetskii et al. (GCN 4599
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 ).

The extrapolated fluence in the 2-30 keV energy band is 
(1.8 � 0.5) x 10-6 erg cm-2, the fluence in the 30-400 keV energy
band is (9.5 � 1) x 10-6 erg cm-2, and the extrapolated fluence in the 
2-400 keV energy band is (11 � 1) x 10-6 erg cm-2.  The ratio of the 
2-30 keV fluence and the 30-400 keV fluence is 0.19; therefore, the 
hardness of the main peak of GRB 060124 corresponds to that of a 
classical hard GRB.

The pseudo-redshift estimate for this burst is pz = 2.3 � 1.2

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

We observed the GRB060124 error box  (Holland et al., GCN 4570
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 ) with AT-64
telescope of CrAO observatory on Jan. 24 between (UT) 17:43:32 and 18:51:06.
The optical afterglow (Kann, GCNs 4577
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 , 4579
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 ) is detected in our
unfiltered 36x60 sec stacked image.

The detailed photometry is underway and should take into account the tail of
nearby bright star. The 3 sigma upper limit of our stacked image is R ~ 20m.

This message can be cited.

G. Greco, C. Bartolini, A. Guarnieri, A. Piccioni (Bologna University), G. Pizzichini (INAF IASF Bologna), R. Silvotti (INAF Napoli), D. Nanni, F. Terra (Second University of Rome "Tor Vergata") and I. Bruni (INAF Bologna)   report:

On January 25, 2006 in spite of the unfavorable weather conditions (seeing=3.4 arcsec) we tried to observe the OT of GRB 060124 (Holland et al. GCN 4570
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 ; Mangano et al., GCN 4578
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 ) with the 152 cm Loiano Telescope and the BFOSC camera system. We obtained three images of 20 min in the Rc filter.   The OT first reported by Kann (GCN 4577
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 ) was not detectable in our frames, which have the following limiting magnitudes derived from the USNO-A2.0 catalogue:

      Mean time (UT) 		Mag
		 	
 	22:45:51 	 	18.7 
 	23:53:00 	 	19.2 	 	
 	26:06:48 	 	19.2
 	
The third observation has been posted in our public directory from where it can be retrieved by sftp using hostname: ermione.bo.astro.it, username: publicGRB, password: GRB_bo.

A. Henden (AAVSO/USNO) reports on behalf of the USNO GRB Team:

We have acquired BVRcIc all-sky photometry for an 11x11 arcmin
field centered on the coordinates of the optical afterglow
(Kann et al., GCN 4577
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 ) for the Swift burst GRB060124
(Holland et al., GCN 4570
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 ) with the USNOFS 1.0-m telescope
on one photometric night.  Stars brighter than V=13.5 are
saturated and should be used with care.  We have placed the
photometric data on our anonymous ftp site:
ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb060124.dat

The astrometry in this file is based on linear plate solutions
with respect to USNO-A2.  The external errors are about 300mas.
The estimated external photometric error is about 0.02mag.

As always, you should check the dates on the .dat file prior to
final publication to get the latest photometry.  There is
a README file on the ftp directory to give you information
about the procedures used to calibrate these fields.

V.Rumyantsev (CrAO), V.Biryukov (SAI, MSU), and A.Pozanenko (IKI) on behalf
of larger GRB follow up collaboration report:

We  observed the  afterglow (Kann,   GCN 4577
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 , 4579
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 ) of GRB060124   (Holland
et al. GCN 4570
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 ) with 2.6 m Shajn telescope of CrAO. The BVRI observation is
started on Jan.24 (UT)19:00. The afterglow is clearly visible in single 60
sec of R-band exposure. Preliminary brightness estimation of the OT at the
start of observation is R~19.5.

The observation is continuing.
The message may be cited.

V.Rumyantsev (CrAO), V.Biryukov (SAI, MSU), and A.Pozanenko (IKI) on behalf
of larger GRB follow up collaboration report:

We  observed the  afterglow (Kann,   GCN 4577
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 , 4579
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 ) of GRB060124   (Holland
et al. GCN 4570
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 ) with 2.6 m Shajn telescope of CrAO. The BVRI observation is
started on Jan.24 (UT)19:00. The afterglow is clearly visible in single 60
sec of R-band exposure. Preliminary brightness estimation of the OT at the
start of observation is R~20.1.

The observation is continuing.
The message may be cited.

Dale A. Frail (NRAO) reports on behalf of a larger collaboration:

"We used the Very Large Array to observe the long Swift burst
GRB060124 (GCN 4586
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 ; GCN 4570
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 ) at a frequency of 8.46 GHz on 2006
February 3.91 UT.  No radio emission is detected at the position of
the optical afterglow (GCN 4577
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 ) with a formal flux density value
of -3 +/- 31 uJy.

No further observations are planned.

The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."