////////////////////////////////////////////////////////////////////// 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. ////////////////////////////////////////////////////////////////////// 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. ////////////////////////////////////////////////////////////////////// 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. ////////////////////////////////////////////////////////////////////// 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1229 SUBJECT: GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE DATE: 02/01/28 03:53:04 GMT FROM: George Ricker at MIT 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1230 SUBJECT: GRB010921 Optical Observations DATE: 02/01/28 06:55:32 GMT FROM: Don Lamb at U.Chicago 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1231 SUBJECT: GRB020127 Optical Observations -- Erratum to GCN 1230 DATE: 02/01/28 07:11:33 GMT FROM: Don Lamb at U.Chicago The subject of GCN 1230 should read "GRB020127." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1235 SUBJECT: GRB020127: Optical observations DATE: 02/01/30 16:26:26 GMT FROM: Alexei Pozanenko at IKI, Moscow 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1241 SUBJECT: GRB020127: Chandra Observations and Prospective Counterparts DATE: 02/02/04 14:06:53 GMT FROM: Derek Fox at CIT 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." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1245 SUBJECT: GRB020127 Optical Observations DATE: 02/02/06 02:00:48 GMT FROM: Brian Lee at Fermilab 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/ --------------- //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1246 SUBJECT: GRB020127, WSRT radio observations DATE: 02/02/06 16:40:00 GMT FROM: Evert Rol at U.Amsterdam 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)." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1249 SUBJECT: GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts DATE: 02/02/15 04:09:29 GMT FROM: Derek Fox at CIT 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." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1250 SUBJECT: GRB020127: Palomar and VLA Observations of Possible Counterparts DATE: 02/02/15 04:25:34 GMT FROM: Derek Fox at CIT 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." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1257 SUBJECT: GRB020127: Further VLA Observations of Possible Counterparts DATE: 02/02/22 23:53:21 GMT FROM: Derek Fox at CIT 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." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1306 SUBJECT: GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow DATE: 02/03/24 21:43:30 GMT FROM: Derek Fox at CIT 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."