//////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4570 SUBJECT: GRB 060124: Swift-BAT detection of a burst DATE: 06/01/24 16:27:17 GMT FROM: David Burrows at PSU/Swift 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4572 SUBJECT: GRB060124:MASTER optical observation DATE: 06/01/24 17:45:05 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs 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 //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4574 SUBJECT: GRB 060124: Optical Observations at Tautenburg DATE: 06/01/24 19:18:07 GMT FROM: Alexander Kann at TLS Tautenburg 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) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4576 SUBJECT: GRB060124, optical observation DATE: 06/01/24 19:36:11 GMT FROM: Eri Sonoda at U of Miyazaki/Japan 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) 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." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4577 SUBJECT: GRB 060124: Optical Afterglow Candidate from Tautenburg DATE: 06/01/24 19:45:19 GMT FROM: Alexander Kann at TLS Tautenburg D. A. Kann reports on behalf of the Tautenburg GRB team: Further inspection of the Tautenburg images (Kann, GCN 4574) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4578 SUBJECT: GRB 060124: XRT position DATE: 06/01/24 20:51:21 GMT FROM: Gianpiero Tagliaferri at OAB-INAF 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). 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). 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4579 SUBJECT: GRB 060124: Confirmation of the Afterglow DATE: 06/01/24 20:52:27 GMT FROM: Alexander Kann at TLS Tautenburg 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) of Swift GRB 060124 (S. T. Holland et al., GCN 4570) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4580 SUBJECT: GRB 060124: Swift/UVOT Observation DATE: 06/01/24 21:01:27 GMT FROM: Stephen Holland at USRA/NASA/GSFC/SSC 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) 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). 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4581 SUBJECT: GRB 060124: TAROT optical limits DATE: 06/01/24 21:24:46 GMT FROM: Alain Klotz at CESR-CNRS 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4586 SUBJECT: GRB 060124: Extremely long burst, Swift-BAT refined analysis DATE: 06/01/25 01:02:04 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift 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). 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4587 SUBJECT: GRB060124: optical observations at Asiago DATE: 06/01/25 02:48:39 GMT FROM: Nicola Masetti at INAF-IASF,Bologna 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) of GRB060124 (Holland et al. GCN 4570; Mangano et al., GCN 4578) 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." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4588 SUBJECT: GRB 060124 : Optical observation at Xinglong and Kiso DATE: 06/01/25 04:56:49 GMT FROM: Yuji Urata at RIKEN 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4589 SUBJECT: GRB 060124: R band Observations DATE: 06/01/25 06:50:43 GMT FROM: Kuntal Mishra at ARIES,Nainital,India Kuntal Misra (ARIES, Nainital) on behalf of a larger Indian GRB collaboration We observed the field of GRB 060124 (SWIFT trigger 178750; GCN 4570) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4590 SUBJECT: GRB 060124: XRT refined analysis DATE: 06/01/25 07:48:31 GMT FROM: Albert Kong at MIT 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). 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) 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) and 1 arcmin from the refined BAT observation (Fenimore GCN 4586). 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4591 SUBJECT: GRB 060124: MDM Optical Spectrum DATE: 06/01/25 08:15:25 GMT FROM: Nestor Mirabal at U Michigan 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." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4592 SUBJECT: GRB 060124: Keck Absorption Redshift DATE: 06/01/25 09:40:11 GMT FROM: S. Bradley Cenko at Caltech 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) 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), 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) we find an isotropic-equivalent gamma-ray energy of 8.9e52 erg." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4593 SUBJECT: GRB 060124: Keck optical spectrum DATE: 06/01/25 10:09:22 GMT FROM: Jason Prochaska at UCO/Lick Obs 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) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4596 SUBJECT: GRB 060124: ART optical limits during the burst DATE: 06/01/25 12:45:04 GMT FROM: Ken ichi Torii at RIKEN K. Torii (Osaka U.) reports on behalf of the ART collaboration: The error region of GRB 060124 (Holland et al., GCN 4570) 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). 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; Kann, Henze, & Laux, GCN 4579), 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 ============================= //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4597 SUBJECT: GRB 060124 Optical Observations DATE: 06/01/25 13:19:43 GMT FROM: T.P. Prabhu at Indian Astro. Obs. 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) 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) and confirmed by Kann et al (GCN 4579) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4598 SUBJECT: GRB060124: detailed XRT analysis DATE: 06/01/25 17:57:58 GMT FROM: Giancarlo Cusumano at INAF-IASFA 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) 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); 6.7 arcsec from the position given by Mangano et al. (GCN 4578 ) based on 15 s observation in PC mode, and 0.6" from the position given by Kong et al (GCN 4590). Moreover the refined coordinates are 2.7" from the optical counterpart detected by Kann (GCN 4577). 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4599 SUBJECT: Konus-Wind observation of GRB 060124 DATE: 06/01/25 18:41:43 GMT FROM: Valentin Pal'shin at Ioffe Inst 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; Fenimore et al., GCN 4586) 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). 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 ) 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/ //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4601 SUBJECT: GRB 060124: HETE detection and spectrum of the main peak DATE: 06/01/26 02:07:59 GMT FROM: Don Lamb at U.Chicago 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) 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, Fenimore et al. GCN 4586) 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). 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 //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4603 SUBJECT: GRB060124: optical observation DATE: 06/01/26 13:11:41 GMT FROM: Vasilij Rumjantsev at CrAO 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) 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, 4579) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4605 SUBJECT: GRB060124 optical observations DATE: 06/01/27 13:09:22 GMT FROM: Adalberto Piccioni at Astronomy, Bologna U. 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; Mangano et al., GCN 4578) 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) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4607 SUBJECT: GRB060124, BVRcIc field calibration DATE: 06/01/27 17:17:17 GMT FROM: Arne A. Henden at AAVSO 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) for the Swift burst GRB060124 (Holland et al., GCN 4570) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4609 SUBJECT: GRB060124: optical observations DATE: 06/01/27 23:25:48 GMT FROM: Alexei Pozanenko at IKI, Moscow 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, 4579) of GRB060124 (Holland et al. GCN 4570) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4610 SUBJECT: GRB060124: optical observation DATE: 06/01/27 23:44:10 GMT FROM: Vasilij Rumjantsev at CrAO 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, 4579) of GRB060124 (Holland et al. GCN 4570) 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. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4662 SUBJECT: GRB 060124: Radio Observations DATE: 06/02/04 17:30:32 GMT FROM: Dale A. Frail at NRAO 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; GCN 4570) 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) 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."