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GRB 020127

GCN Circular 1229

Subject
GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
Date
2002-01-28T03:53:04Z (23 years ago)
From
George Ricker at MIT <grr@space.mit.edu>
GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE

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

G. Crew, R. Vanderspek, J. Doty, G. Monnelly, J. Villasenor, N. Butler,
T. Cline, J.G. Jernigan, A. Levine, F. Martel, E. Morgan, G.
Prigozhin, J. Braga, R. Manchanda, and G. Pizzichini, on behalf of
the HETE Operations and HETE Optical-SXC Teams;

M. Matsuoka, Y. Shirasaki, T. Tamagawa, K. Torii, T. Sakamoto,
A. Yoshida, E. Fenimore, M. Galassi, T. Tavenner, T. Donaghy, and
C. Graziani, on behalf of the HETE WXM Team;

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

write:

At 20:57:24.73 UTC (75444.73 s UT) on 27 January, the HETE FREGATE 
and WXM instruments detected and localized a double-peaked GRB. The 
burst, H1902, was promptly reported as a GCN Alert Notice within 97 
seconds of the detection time. [Because of the proximity of the 
nearly-full moon to the HETE optical cameras, the burst alert 
downlink contained no real time optical aspect solution, even though 
there was an accurate on-board X-ray localization. When this 
condition arises, the ground relay software computes a nominal 
localization assuming the satellite is pointed anti-sun, and 
increases the error circle diameter to a nominal 4 degrees. For this 
burst, the actual pointing direction was unusually far from nominal 
(i.e. ~8 degrees offset).]

Accurate aspect was derived for H1902 from a full data set on the 
ground. In a followup GCN Notice issued 1.76 hours after the GRB, the 
result of an initial ground analysis localization was reported with a 
90% confidence error circle radius of 12 arcmin. Further ground 
analysis of the optical aspect data has produced a significantly 
improved location which can be expressed as a circle with a 90% 
confidence radius of 8 arc minutes centered at:

RA = +08h 15m 05.7s, Dec = +36d 44' 31" (J2000)

The revised error circle reported here is displaced by 9 arc minutes 
from the  best-fit location found in the initial HETE ground analysis 
and reported in a GCN Notice (at 27 Jan 2002 22:43:00 UT).

GRB020127(=H1902) consists of two peaks separated by 5.5s, with 
durations in the FREGATE 32-400 keV band of ~2s and 0.7s, 
respectively. A total of 870 counts were detected by FREGATE in the 
first peak, and 580 counts in the second peak, respectively.  In the 
8-40 keV FREGATE band, the peak flux in 0.073s was >2 x 10-7 ergs 
cm-2 s-1(ie >7 x Crab flux). In the 2-25 keV WXM band, the 
statistical significance of the burst was 21 sigma.

This message is quotable.

GCN Circular 1231

Subject
GRB020127 Optical Observations -- Erratum to GCN 1230
Date
2002-01-28T07:11:33Z (23 years ago)
From
Don Lamb at U.Chicago <lamb@oddjob.uchicago.edu>
The subject of GCN 1230 should read "GRB020127."

GCN Circular 1232

Subject
IPN triangulation of GRB020127 (=H1902)
Date
2002-01-28T19:29:57Z (23 years ago)
From
Kevin Hurley at UCBerkeley/SSL <khurley@sunspot.ssl.berkeley.edu>
K. Hurley, on behalf of the Ulysses and HETE GRB teams;

E. Mazets and S. Golenetskii, on behalf of the Konus-WIND
GRB team; 

T. Cline, on behalf of the Ulysses, Konus, and HETE GRB teams;

G. Ricker, D. Lamb, and S. Woosley on behalf of the HETE Science Team;

R. Vanderspek, G. Crew, J. Doty, G. Monnelly, J. Villasenor, N.
Butler, T. Cline, J.G. Jernigan, A. Levine, F. Martel, E. Morgan, G.
Prigozhin, J. Braga, R. Manchanda, and G. Pizzichini, on behalf of
the HETE Operations and HETE Optical-SXC Teams;

N. Kawai, M. Matsuoka, Y. Shirasaki, T. Tamagawa, K. Torii, T.
Sakamoto, A. Yoshida, E. Fenimore, M. Galassi, T. Donaghy, C. Graziani, 
and T. Tavenner, on behalf of the HETE WXM Team;

J-L Atteia, M. Boer, J-F Olive, and J-P Dezalay, on behalf
of the HETE FREGATE Team;

report:

Ulysses and Konus-Wind observed GRB020127 (=H1902, GCN 1229).
Triangulation gives an annulus centered at RA(2000)= 263.183 deg.,
Decl.(2000)=+67.504 deg., with radius 71.317 +/- 0.101 deg. (3 sigma).
This annulus intersects the 90% confidence HETE WXM error circle (GCN
1229) at four points:

RA(2000)	Dec(2000)
123.884         +36.643
123.616         +36.701
123.852         +36.859
123.780         +36.875

The combined annulus/error circle has an area approximately 15%
smaller than the error circle alone, or approximately 165 square
arcminutes.

A map has been posted at ssl.berkeley.edu/ipn3/020127.

GCN Circular 1234

Subject
GRB 020127, I-band observations starting 3.14-hr after the event
Date
2002-01-29T02:02:14Z (23 years ago)
Edited On
2024-11-16T16:22:38Z (7 months ago)
From
Alberto Castro-Tirado at LAEFF-INTA <ajct@laeff.esa.es>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>
GRB 020127, I-band observations starting 3.14-hr after the event
----------------------------------------------------------------

  José María Castro Cerón, ROA (San Fernando),
  Javier Gorosabel, DSRI (Copenhagen),
  Jochen Greiner, AIP (Potsdam),
  Sylvio Klose, TLS (Tautenburg),
  Jan Snigula, USM (Munich) and
  Alberto J. Castro-Tirado, IAA-CSIC (Granada) and LAEFF-INTA (Madrid)

  report:

  On 28 Jan 2002 we have observed the HETE error box for GRB 020127. The
  first epoch images were centred at the initial ground analysis position
  (= H1902) while the second epoch images were centred at the further ground
  analysis position (Ricker et al. GCN 1229). Third epoch observations were
  centred at the combined IPN annulus/HETE error circle (Hurley et al.,
  GCN 1232).

 Imaging commenced 3.14 hours after the occurence of the burst. All images
  were taken in the I-band, with the 1.23 m telescope at the Centro Astronómico
  Hispano Alemán's Calar Alto Observatory (Almería, Spain). Exposures were
  of 300 s.

  A log of the observations is given below.

  ---------------------------------------------------------------------
  date start   R.A. (2000)  Dec. (2000)   number of  Error box Coverage
     (UT)                                 frames          (%)
  ---------------------------------------------------------------------
  Jan 28.0039  08h 15m 20s  +36° 48' 00"     1             75
  Jan 28.0105  08h 15m 20s  +36° 34' 00"     1             50
  Jan 28.2164  08h 15m 06s  +36° 44' 31"     3             90
  Jan 28.9201  08h 15m 08s  +36° 46' 16"     5            100
  ---------------------------------------------------------------------

  Visual inspection revealed no new object, brighter than the DSS-2 limiting
  magnitude for this field (R ~21.5), in the 75% of the combined IPN
  annulus/HETE error box  taken 3.14 hours after the GRB, when compared to
  the third epoch images (~22 hours later, I_lim = 19.5), in agreement with
  the ARC 3.5-m observations (Lamb et al. GCN 1230).

 This message may be cited.

GCN Circular 1235

Subject
GRB020127: Optical observations
Date
2002-01-30T16:26:26Z (23 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
S.Bondar' (Kosmoten), A.Pozanenko (IKI), V.Rumyantsev (CrAO) and G.Beskin
(SAO) report:

We have observed the entire error box of GRB 020127 / HETE #1902 with 600mm
automated telescope (TT600) of Kosmoten observatory. Observation started
after HETE Ground Analysis (HETE #1902, Seq_Num: 4).

3 sets of images were obtained at 27 Jan  23:40 (i.e. 2h 43m after bursts),
28 Jan 00:55 and 28 Jan  02:35. Each sets covered the entire error box by
several images with fixed exposure of 8 sec. The observations were carried
under unfavorable conditions due to increasing cirrus.

No new objects were found in the GRB error box (Ricker et al., GCN 1229).
The limiting magnitudes of the observations are following:

Date              Limiting magnitude
Jan 27.986    14.1
Jan 28.038    ~13.7
Jan 28.108    ~13.5

This message may be cited.

GCN Circular 1241

Subject
GRB020127: Chandra Observations and Prospective Counterparts
Date
2002-02-04T14:06:53Z (23 years ago)
From
Derek Fox at CIT <derekfox@astro.caltech.edu>
Derek W. Fox (Caltech) reports on behalf of the Caltech-NRAO-CARA GRB
colloboration:

"We have initiated a two-pointing sequence of Chandra ACIS-I
observations of this event (HETE #1902, GCN 1229) in order to identify
its X-ray counterpart.  Analysis of the first 10-ksec observation
(start time Jan 31.95 UT) reveals the presence of eleven probable
X-ray sources within or near the joint HETE-IPN localization (GCN
1232).  Correcting the Chandra aspect by roughly one arcsec by
reference to three bright USNO stars with X-ray counterparts in the
field, we derive the following positions, approximate counts, and
(wavdetect) uncertainties:

    Source         RA               Dec         Cts     Notes
   ================================================================
     cxo01   08 14 42.57(4)   +36 49 11.2(5)     54    DPOSS
     cxo02   08 14 52.00(7)   +36 43 39.4(9)     18
     cxo03   08 15 17.83(6)   +36 39 11.9(8)     47
     cxo04   08 15 24.36(2)   +36 41 01.1(5)    134    USNO (faint)
     cxo05   08 15 27.35(9)   +36 40 51.7(12)    25
     cxo06   08 15 27.93(11)  +36 49 40.5(8)     27
     cxo07   08 15 33.58(7)   +36 46 14.8(11)    22    USNO (faint)
     cxo08   08 15 39.17(6)   +36 47 49.1(12)    46    USNO+2MASS
     cxo09   08 15 40.77(9)   +36 43 17.0(10)    19
     cxo10   08 15 42.48(5)   +36 45 36.1(8)    108    USNO+2MASS
     cxo11   08 15 44.77(9)   +36 41 13.1(8)     28
   ================================================================

Numbers in parentheses indicate the uncertainty in the preceding
digits.  Table notes indicate the presence of a likely counterpart to
the X-ray source in one or more sky catalogs (DPOSS catalog for the
field available at http://www.srl.caltech.edu/~react/GRB020127.html).

Please note that these results are preliminary and subject to
revision.  The Chandra follow-up observation is currently scheduled
for Feb 11 UT."

GCN Circular 1245

Subject
GRB020127 Optical Observations
Date
2002-02-06T02:00:48Z (23 years ago)
From
Brian Lee at Fermilab <bclee@fnal.gov>
B. C. Lee, D. Q. Lamb, R. J. McMillan, D. G. York and D. E. Vanden Berk,
on behalf of the SDSS GRB team, report:

The field of GRB020127 (= H1902) (Ricker et al., GCN 1229) was
observed by the SDSS in two interlaced runs on 2001 December 18.34 and
19.30 UTC in the normal course of SDSS operations.  We have examined
the SDSS u* g* r* i* z* images in the vicinity of the eleven probable
X-ray sources seen in the first Chandra follow-up observation (Fox,
GCN 1241) that lie near or within the joint HETE-IPN localization
(Hurley et al., GCN 1232).  The tables below list the properties of
the objects we find that lie closest to the locations of the probable
X-ray sources.  The distance to the X-ray source position (col 3) is
listed in arcseconds.  SDSS RMS astrometric errors are 0.1 arcsec or
less.

------------------------------------------------------------------------------
       Nearest
X-ray  Optical    RA       Dec   Distance Photo     r* mag       Comment
Source Source    (deg)    (deg)  (arcsec) Class
------------------------------------------------------------------------------
cxo01  sdss01  123.67710 36.81988  0.86   star    20.22+/-0.02  Probable QSO
cxo02  sdss02  123.70650 36.72886 29.68   galaxy  22.84+/-0.28  Too faint
cxo03  sdss03  123.82472 36.65235  3.67   galaxy  21.39+/-0.06  QSO colors
cxo04  sdss04  123.85118 36.68411  1.94   galaxy  19.77+/-0.02
cxo05  sdss05  123.86302 36.68097  2.71   galaxy  22.76+/-0.18  Too faint
cxo06  sdss06  123.86641 36.82857  2.36   galaxy  21.44+/-0.06
cxo07  sdss07  123.88969 36.77076  0.65   star    20.33+/-0.03  Probable QSO
cxo08  sdss08  123.91376 36.79532  6.16   ------  15.06+/-0.01  Saturated star
cxo09  sdss09  123.92058 36.72213  3.35   galaxy  22.71+/-0.18  Too faint
cxo10  sdss10  123.92700 36.75947  2.01   ------  14.90+/-0.01  Saturated star
cxo11  sdss11  123.93778 36.68775  4.56   galaxy  22.20+/-0.11  Too faint
------------------------------------------------------------------------------
Table notes:

Photo class: the SDSS photometric pipeline's morphological classification.
             Star = PSF like, galaxy = extended.
Probable QSO/QSO colors: This object's colors are similar to that of a
                         QSO.
Too faint: This object is faint enough that classification,
           magnitudes, and colors are likely to be unreliable.
Saturated: This object is saturated in one or more filters.  Position,
           magnitudes, and photo class are unreliable.

------------------------------------------------------------------------------
     Photo
sdss Class      r*           u*-g*        g*-r*        r*-i*        i*-z*
------------------------------------------------------------------------------
01   star     20.22+/-0.02  0.37+/-0.05  0.05+/-0.03  0.02+/-0.04  0.20+/-0.09
02** galaxy   22.84+/-0.28 -0.37+/-0.54  1.26+/-0.40  0.25+/-0.33 -0.01+/-0.47
03   galaxy   21.39+/-0.06 -0.19+/-0.15  0.42+/-0.09  0.14+/-0.09  0.38+/-0.18
04   galaxy   19.77+/-0.02  1.38+/-0.15  0.58+/-0.03  0.47+/-0.03  0.13+/-0.05
05** galaxy   22.76+/-0.18 -0.05+/-0.71  0.45+/-0.27  0.26+/-0.26  0.93+/-0.34
06   galaxy   21.44+/-0.06  0.23+/-0.28  0.80+/-0.11  0.14+/-0.09  0.34+/-0.19
07   star     20.33+/-0.03  0.19+/-0.07  0.10+/-0.04  0.27+/-0.04 -0.01+/-0.09
08** ------   15.06+/-0.01 -2.08+/-0.03  0.01+/-0.02  0.14+/-0.02  1.87+/-0.02
09** galaxy   22.71+/-0.18 -0.72+/-0.38  0.64+/-0.29  0.71+/-0.22 -0.05+/-0.42
10** ------   14.90+/-0.01 -0.15+/-0.03 -0.09+/-0.02  0.32+/-0.02  2.46+/-0.02
11** galaxy   22.20+/-0.11  0.95+/-0.69  0.53+/-0.18  0.91+/-0.13  0.62+/-0.16
------------------------------------------------------------------------------
Table note:

** Saturated or faint star: magnitudes, colors, classification and
                            (for saturated stars) position are unreliable.

-- 
Brian C. Lee         - bclee@fnal.gov -          630-840-6646
Fermilab MS 127 WH7W -   PO Box 500   - Batavia IL 60510-0500
---------------- http://home.fnal.gov/~bclee/ ---------------

GCN Circular 1246

Subject
GRB020127, WSRT radio observations
Date
2002-02-06T16:40:00Z (23 years ago)
From
Evert Rol at U.Amsterdam <evert@astro.uva.nl>
GRB020127, WSRT radio observations

Evert Rol, Paul Vreeswijk, Lex Kaper, (University of Amsterdam), Richard
Strom (ASTRON, UoA) report, on behalf of a larger collaboration:

"We have performed observations of the HETE error circle of GRB020127
(Ricker et al, GCN 1229) with the Westerbork Synthesis Radio
Telescope. We observed at 2.3 GHz at two epochs, Jan 28.72-29.22 and
Feb 3.71-4.21, and at 1.4 GHz at one epoch, Jan 28.72-29.22.

At 2.3 GHz, we detect six sources within the combined HETE/IPN error
circle (Hurley et al., GCN 1232) to a limit of 0.62 mJy (3 sigma). No
sources show variability between the two observations. The 1.4 GHz
observation also contains these six sources, none of which has a
positive spectral index.

We do not find any radio counterparts to the Chandra X-ray sources
(Fox, GCN 1241)."

GCN Circular 1249

Subject
GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
Date
2002-02-15T04:09:29Z (23 years ago)
From
Derek Fox at CIT <derekfox@astro.caltech.edu>
Derek W. Fox (Caltech) reports on behalf of the Caltech-NRAO-CARA GRB
collaboration:

"We have made a comprehensive analysis of the data from two 10-ks
Chandra ACIS-I observations of the HETE-IPN localization region for
GRB020127 (HETE 1902; GCNs 1229, 1232, 1241).  The full source
catalogs for these observations contain 48 and 50 sources,
respectively; approximately four sources in each epoch are anticipated
to be spurious detections.  We identify three possible counterparts
based on their fading behavior between the Chandra observations (which
began at Jan 31.95 UT and Feb 11.46 UT, respectively) and the absence
of a bright stellar or galactic counterpart in archival images:

 Source        RA               Dec           Nsig     F1     F2
===================================================================
  A14=B16   08 15 01.42(1)   +36 46 33.9(1)   13.6   84(16)  19(6)
  A45       08 15 42.78(7)   +36 47 00.2(10)   5.7   28(7)  <14
   A7       08 14 47.82(3)   +36 49 35.4(3)    4.1   13(4)  <14
===================================================================

Numbers in parentheses indicate the uncertainty in the preceding
digits, and positional uncertainties do not account for the overall
Chandra aspect uncertainty of roughly one arcsec.  Nsig is the nominal
(single-trial) significance of the source detection as reported by
wavdetect.  F1 and F2 are source count rates for the first and second
epochs, respectively, in units of photons cm^(-2) ks^(-1) (0.3-7 keV);
upper limits are roughly two-sigma.  Source A14 is detected in the
second epoch as source B16, while neither source A45 nor source A7 are
detected in the second epoch.

We note explicitly that the sources above are not the only sources
within the HETE-IPN localization to show variability between the two
epochs; however, they are the only sources, not associated with bright
stellar or galactic counterparts, that show convincing evidence of a
decline in flux.  The full source catalog for the two observations is
available at the following URL:

  http://www.astro.caltech.edu/~derekfox/grb020127/chandra.html

Given the strength of source A14 (=B16) in the first observation, and
its observed fading behavior -- which is consistent with a t^(-1.2)
power-law referred to the epoch of GRB020127 -- we consider source A14
to be the most likely candidate for the afterglow of GRB020127."

GCN Circular 1250

Subject
GRB020127: Palomar and VLA Observations of Possible Counterparts
Date
2002-02-15T04:25:34Z (23 years ago)
From
Derek Fox at CIT <derekfox@astro.caltech.edu>
Derek W. Fox (Caltech) and Dale A. Frail (Caltech/NRAO) report on
behalf of a larger collaboration:

"On Feb 4 UT (g' band) and Feb 6 UT (r' band) we observed the HETE-IPN
localization region of GRB020127 (GCN 1232) with the Large Format
Camera on the Hale Telescope on Mt. Palomar.  Reduction of images
covering the full localization region excludes the presence of any
optical counterparts to the three X-ray sources A14, A45, and A7 of
GCN 1249, at the respective epochs of these images, to limiting
magnitudes of g'~23 and r'~23.3."

"Separately, on Feb 14.2 UT we observed the region surrounding Source
A14 of GCN 1249 with the VLA.  Within the roughly one-arcsecond
Chandra localization we find a weak radio source with an 8.5 GHz flux
density of 157 +/- 43 uJy located at (J2000) RA 08:15:01.4183(2), Dec
+36:46:33.43(3).  Follow-up observations are underway to confirm this
source detection."

GCN Circular 1257

Subject
GRB020127: Further VLA Observations of Possible Counterparts
Date
2002-02-22T23:53:21Z (23 years ago)
From
Derek Fox at CIT <derekfox@astro.caltech.edu>
Derek W. Fox and Edo Berger (Caltech), with Dale A. Frail
(Caltech/NRAO), report on behalf of the Caltech-NRAO-CARA GRB
collaboration: 

"On Feb 16.2 UT and Feb 22.0 UT we re-observed the position of Source
A14 of GCN 1249 with the VLA.  Three-sigma upper limits on the flux
density of any 8.5 GHz source on these two dates are 110 uJy and 150
uJy, respectively.  In particular, the previously identified 157 +/-
43 uJy radio source at (J2000) RA 08:15:01.4183(2), Dec
+36:46:33.43(3) (GCN 1250) is not detected at either epoch.  Without a
confirming detection of this source, we cannot exclude the possibility
that the original Feb 14.2 UT detection was spurious.  

On Feb 22.0 UT we also observed the regions surrounding Sources A45
and A7 of GCN 1249.  Three-sigma upper limits on the 8.5 GHz flux
density of any radio sources on this date are 150 uJy for each of
these regions."

GCN Circular 1306

Subject
GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
Date
2002-03-24T21:43:30Z (23 years ago)
From
Derek Fox at CIT <derekfox@astro.caltech.edu>
D.W. Fox, S.G. Djorgovski, and S.R. Kulkarni (Caltech) report on
behalf of a larger collaboration:

"We have imaged the area surrounding Source A14 of GCN 1249, a
candidate X-ray afterglow for the dark burst GRB020127, using the
Echelle Spectrograph and Imager (ESI) on the Keck-II telescope.  In a
summed R-band image with 45 minutes total exposure in subarcsecond
seeing on March 13.3 (UT) we detect an extended object that we suggest
is the host galaxy of this GRB.  The corresponding X-ray source A14
may in this case be identified as the likely X-ray afterglow of
GRB020127, which is therefore located at:

    RA = 08 15 01.42, Dec = +36 46 33.9 (J2000)

with an uncertainty of roughly 1".  A smoothed image of a portion of
the ESI field may be found at

    http://www.astro.caltech.edu/~derekfox/grb020127/ESI_Rsum.gif

In light of this proposed identification, we suggest as well that the
coincident weak radio source reported in GCN 1250 was the radio
afterglow of this GRB."

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