- GCN/BACODINE POSITION NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sun 27 Jan 02 20:59:01 UT
NOTICE_TYPE: HETE S/C_Alert
TRIGGER_NUM: 1902, Seq_Num: 1
GRB_DATE: 12301 TJD; 27 DOY; 02/01/27
GRB_TIME: 75444.73 SOD {20:57:24.73} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 287 [cnts/s] on a 0.160 [sec] timescale
SC_-Z_RA: 130 [deg]
SC_-Z_DEC: 18 [deg]
WXM_CNTR_RA: 135.859d {+09h 03m 26s} (J2000),
135.892d {+09h 03m 34s} (current),
135.056d {+09h 00m 13s} (1950)
WXM_CNTR_DEC: +39.730d {+39d 43' 48"} (J2000),
+39.722d {+39d 43' 18"} (current),
+39.928d {+39d 55' 42"} (1950)
WXM_MAX_SIZE: 240.00 [arcmin] diameter
WXM_LOC_SN: 7 sig/noise (pt src in image)
SUN_POSTN: 310.17d {+20h 40m 41s} -18.33d {-18d 19' 45"}
SUN_DIST: 158.04 [deg]
MOON_POSTN: 115.27d {+07h 41m 05s} +23.73d {+23d 44' 01"}
MOON_DIST: 23.62 [deg]
MOON_ILLUM: 98 [%]
GAL_COORDS: 182.57,41.62 [deg] galactic lon,lat of the burst
COMMENTS: Probable GRB.
COMMENTS: WXM error box is circular; not rectangular.
- GCN/BACODINE POSITION NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sun 27 Jan 02 20:59:41 UT
NOTICE_TYPE: HETE S/C_Update
TRIGGER_NUM: 1902, Seq_Num: 2
GRB_DATE: 12301 TJD; 27 DOY; 02/01/27
GRB_TIME: 75444.73 SOD {20:57:24.73} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 287 [cnts/s] on a 0.160 [sec] timescale
SC_-Z_RA: 130 [deg]
SC_-Z_DEC: 18 [deg]
WXM_CNTR_RA: 135.859d {+09h 03m 26s} (J2000),
135.892d {+09h 03m 34s} (current),
135.056d {+09h 00m 13s} (1950)
WXM_CNTR_DEC: +39.730d {+39d 43' 48"} (J2000),
+39.722d {+39d 43' 18"} (current),
+39.928d {+39d 55' 42"} (1950)
WXM_MAX_SIZE: 240.00 [arcmin] diameter
WXM_LOC_SN: 7 sig/noise (pt src in image)
SUN_POSTN: 310.17d {+20h 40m 41s} -18.33d {-18d 19' 45"}
SUN_DIST: 158.04 [deg]
MOON_POSTN: 115.27d {+07h 41m 05s} +23.73d {+23d 44' 01"}
MOON_DIST: 23.62 [deg]
MOON_ILLUM: 98 [%]
GAL_COORDS: 182.57,41.62 [deg] galactic lon,lat of the burst
COMMENTS: Probable GRB.
COMMENTS: WXM error box is circular; not rectangular.
- GCN/BACODINE POSITION NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Sun 27 Jan 02 22:43:00 UT
NOTICE_TYPE: HETE Ground Analysis
TRIGGER_NUM: 1902, Seq_Num: 4
GRB_DATE: 12301 TJD; 27 DOY; 02/01/27
GRB_TIME: 75444.72 SOD {20:57:24.72} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 287 [cnts/s] on a 0.160 [sec] timescale
SC_-Z_RA: 130 [deg]
SC_-Z_DEC: 18 [deg]
WXM_CNTR_RA: 123.948d {+08h 15m 48s} (J2000),
123.982d {+08h 15m 56s} (current),
123.134d {+08h 12m 32s} (1950)
WXM_CNTR_DEC: +36.692d {+36d 41' 31"} (J2000),
+36.686d {+36d 41' 08"} (current),
+36.846d {+36d 50' 45"} (1950)
WXM_MAX_SIZE: 24.00 [arcmin] diameter
WXM_LOC_SN: 15 sig/noise (pt src in image)
SUN_POSTN: 310.17d {+20h 40m 41s} -18.33d {-18d 19' 45"}
SUN_DIST: 160.85 [deg]
MOON_POSTN: 115.27d {+07h 41m 05s} +23.73d {+23d 44' 01"}
MOON_DIST: 14.96 [deg]
MOON_ILLUM: 98 [%]
GAL_COORDS: 184.79,31.95 [deg] galactic lon,lat of the burst
COMMENTS: Definite GRB.
COMMENTS: WXM error box is circular; not rectangular.
COMMENTS: Burst_Validity flag is true.
COMMENTS: Invalid localization by flight code.
- GCN/BACODINE POSITION NOTICE
TITLE: GCN/HETE BURST POSITION NOTICE
NOTICE_DATE: Mon 28 Jan 02 01:24:22 UT
NOTICE_TYPE: HETE Ground Analysis
TRIGGER_NUM: 1902, Seq_Num: 5
GRB_DATE: 12301 TJD; 27 DOY; 02/01/27
GRB_TIME: 75444.72 SOD {20:57:24.72} UT
TRIGGER_SOURCE: Trigger on the 25-400 keV band.
GAMMA_RATE: 287 [cnts/s] on a 0.160 [sec] timescale
SC_-Z_RA: 130 [deg]
SC_-Z_DEC: 18 [deg]
WXM_CNTR_RA: 123.774d {+08h 15m 06s} (J2000),
123.808d {+08h 15m 14s} (current),
122.959d {+08h 11m 50s} (1950)
WXM_CNTR_DEC: +36.742d {+36d 44' 31"} (J2000),
+36.736d {+36d 44' 08"} (current),
+36.895d {+36d 53' 42"} (1950)
WXM_MAX_SIZE: 16.00 [arcmin] diameter
WXM_LOC_SN: 15 sig/noise (pt src in image)
SUN_POSTN: 310.17d {+20h 40m 41s} -18.33d {-18d 19' 45"}
SUN_DIST: 160.76 [deg]
MOON_POSTN: 115.27d {+07h 41m 05s} +23.73d {+23d 44' 01"}
MOON_DIST: 14.93 [deg]
MOON_ILLUM: 98 [%]
GAL_COORDS: 184.70,31.83 [deg] galactic lon,lat of the burst
COMMENTS: Definite GRB.
COMMENTS: WXM error box is circular; not rectangular.
COMMENTS: Burst_Validity flag is true.
COMMENTS: WXM data refined since S/C_Last Notice.
COMMENTS: Invalid localization by flight code.
- GCN notice #1229
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 notice #1230
D. Q. Lamb, D. G. York, R. J. McMillan and D. Johnston report:
We have observed the improved HETE error circle for GRB020127 (= H1902)
(GCN 1229) using the ARC 3.5-m telescope at APO under excellent seeing
conditions but a very bright moon on 2002 January 28 beginning at UT
01:38 (4.43 hours after the GRB). A series of images covering an area
somewhat larger than the entire improved HETE error circle was acquired
in SDSS r' and i' filters.
Visual inspection of the series of r' and i' images reveals no new
object brighter than the DSS limiting magnitude for this field (R ~
19.5).
This message is quotable.
- GCN notice #1231
The subject of GCN 1230 should read "GRB020127."
- GCN notice #1232
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 notice #1234
GRB 020127, I-band observations starting 3.14-hr after the event
Jose Maria Castro Ceron, 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 Astronomico
Hispano Aleman's Calar Alto Observatory (Almeria, 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 +36d 48' 00" 1 75
Jan 28.0105 08h 15m 20s +36d 34' 00" 1 50
Jan 28.2164 08h 15m 06s +36d 44' 31" 3 90
Jan 28.9201 08h 15m 08s +36d 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 notice #1235
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 notice #1241
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 notice #1245
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.
- GCN notice #1246
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 notice #1249
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 notice #1250
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 notice #1257
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 notice #1306
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."
- astro-ph/0609170 from 7 Sep 2006
Berger: The ERO Host Galaxy of GRB 020127: Implications for the Metallicity of GRB Progenitors
We present optical and near-IR observations of the host galaxy of GRB 020127,
for which we measure R-K=6.2 mag. This is only the second GRB host to date,
which is classified as an ERO. The spectral energy distribution is typical of a
dusty starburst galaxy, with a redshift, z~1.9, a luminosity, L~5L*, and an
inferred stellar mass of ~10^11-10^12 Msun, two orders of magnitude more
massive than typical GRB hosts. A comparison to the z~2 mass-metallicity (M-Z)
relation indicates that the host metallicity is about 0.5 Zsun. This result
shows that at least some GRBs occur in massive, metal-enriched galaxies, and
that the proposed low metallicity bias of GRB progenitors is not as severe as
previously claimed. Instead we propose that the blue colors and sub-L*
luminosities of most GRB hosts reflect their young starburst populations. This,
along with the locally increased fraction of starbursts at lower stellar mass,
may in fact be the underlying reason for the claimed low metallicity bias of
z<0.2 GRB hosts. Consequently, GRBs and their host galaxies may serve as a
reliable tracer of cosmic star formation, particularly at z>1 where the M-Z
relation is systematically lower, and the star formation rate is dominated by
sub-L* galaxies.
- 1002.3849 from 23 Feb 10
M. Arimoto et al.: Spectral Lag Relations in GRB Pulses Detected with HETE-2
T. Tamagawa, Y. Shirasaki, S. Sugita, I. Takahashi, J.-L. Atteia, A. Pelangeon, R. Vanderspek, C. Graziani, G. Prigozhin, J. Villasenor, J. G.
Jernigan, G. B. Crew, T. Sakamoto, G. R. Ricker, S. E. Woosley, N. Butler, A. Levine, J. P. Doty, T. Q. Donaghy, D. Q. Lamb, E. Fenimore, M.
Galassi, M. Boer, J.-P. Dezalay, J.-F. Olive, J. Braga, R. Manchanda, G. Pizzichini
Using a pulse-fit method, we investigate the spectral lags between the traditional gamma-ray band (50-400 keV) and the X-ray band (6-25 keV)
for 8 GRBs with known redshifts (GRB 010921, GRB 020124, GRB 020127, GRB 021211, GRB 030528, GRB 040924, GRB 041006, GRB 050408) detected with
the WXM and FREGATE instruments aboard the HETE-2 satellite. We find several relations for the individual GRB pulses between the spectral lag
and other observables, such as the luminosity, pulse duration, and peak energy (Epeak). The obtained results are consistent with those for
BATSE, indicating that the BATSE correlations are still valid at lower energies (6-25 keV). Furthermore, we find that the photon energy
dependence for the spectral lags can reconcile the simple curvature effect model. We discuss the implication of these results from various
points of view.
Previous IAU Circulars 
