//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22177 SUBJECT: GRB 171205A: Swift detection of a burst DATE: 17/12/05 07:48:19 GMT FROM: Boris Sbarufatti at PSU V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), A. Y. Lien (GSFC/UMBC) and B. Sbarufatti (PSU) report on behalf of the Swift Team: At 07:20:43 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 171205A (trigger=794972). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 167.447, -12.604 which is RA(J2000) = 11h 09m 47s Dec(J2000) = -12d 36' 12" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). As is usual with an image trigger, the available BAT light curve shows no significant structure. The XRT began observing the field at 07:23:08.5 UT, 144.7 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 167.4144, -12.5857 which is equivalent to: RA(J2000) = +11h 09m 39.46s Dec(J2000) = -12d 35' 08.5" with an uncertainty of 5.0 arcseconds (radius, 90% containment). This location is 132 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy. UVOT took a finding chart exposure of 150 seconds with the White filter starting 153 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.05. Burst Advocate for this burst is V. D'Elia (delia AT asdc.asi.it). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22178 SUBJECT: GRB 171205A: Likely association with low-z spiral galaxy DATE: 17/12/05 08:38:42 GMT FROM: Alexander Kann at TLS Tautenburg L. Izzo, D. A. Kann (both HETH/IAA-CSIC), J. P. U. Fynbo (DARK), A. J. Levan (U. Warwick), and N. R. Tanvir (U. Leicester) note on behalf of the Stargate Consortium: The XRT position of GRB 171205A (V. D'Elia et al. GCN #22177) contains a bright spiral galaxy 2MASX J11093966-1235116 which lies at z = 0.037 according to SIMBAD (6df Galaxy Catalog). The combination of a BAT image trigger, a bright XRT afterglow and lack of a bright optical afterglow may indicate a source similar to XRFs 060218 and 100316D. Multiwavelength follow-up is encouraged. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22179 SUBJECT: GRB 171205A: Enhanced Swift-XRT position DATE: 17/12/05 10:32:58 GMT FROM: Phil Evans at U of Leicester J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team. Using 1358 s of XRT Photon Counting mode data and 2 UVOT images for GRB 171205A, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 167.41406, -12.58891 which is equivalent to: RA (J2000): 11h 09m 39.37s Dec (J2000): -12d 35' 20.1" with an uncertainty of 2.3 arcsec (radius, 90% confidence). This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular was automatically generated, and is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22180 SUBJECT: GRB 171205A: VLT/X-shooter optical counterpart and spectroscopic observations DATE: 17/12/05 11:01:51 GMT FROM: Jonatan Selsing at DARK/NBI L. Izzo (HETH/IAA-CSIC), J. Selsing (DARK), J. Japelj (API, Univ. Amsterdam), B. Milvang-Jensen, J. P. U. Fynbo (both DARK), D. Xu (NAOC), D. A. Kann (HETH/IAA-CSIC), N. R. Tanvir, R. Starling (both U. Leicester), A. J. Levan, K. Wiersema (both U. Warwick), G. Pugliese (API, Univ. Amsterdam), V. D'Elia (ASI-SSDC), and S. Campana (INAF-Brera) report on behalf of the Stargate Consortium: We observed the optical afterglow of GRB 171205A (V. D'Elia et al. GCN #22177) with the ESO VLT/X-shooter spectrograph, covering the wavelength range 3500-20000 AA. Spectroscopy started at 08:56:18 UT on 2017-12-05 (i.e., 1.5 hr after the GRB) and consisted of 1 exposure of 600 s taken in twilight. From the acquisition image prior to the spectroscopy, a new optical transient is clearly detected in the outskirts of the putative host galaxy (L. Izzo et al. GCN #22178) at the following coordinates: RA(J2000) = 11h 09m 39.573s Dec.(J2000) = -12d 35' 17.37" This source is inside the error box reported by (J.P. Osborne et al. GCN #22179). From the acquisition image we measure this source to have m(r)~16.0 mag, calibrated with a nearby Pan-STARRS star. The source continuum is well detected across the entire spectral coverage and clear emission lines are superposed on it identified as Halpha, [N II] 6584, and [S II] 6717/32 located at z = 0.0368, suggesting an association with the nearby galaxy. Additionally, a tentative detection of absorption lines identified as NaI 5891/5897 in the continuum further supports z = 0.0368 as the redshift of the GRB. We acknowledge the excellent support from the ESO staff, particularly Jose Velasquez and Zahed Wahhaj in obtaining these observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22181 SUBJECT: GRB 171205A: Swift/UVOT Detection DATE: 17/12/05 13:45:32 GMT FROM: Sam Emery at MSSL-UCL S.W.K. Emery (UCL-MSSL) and V. D'Elia (ASDC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 171205A 154 s after the BAT trigger (D'Elia et al., GCN Circ. 22177). A source consistent with the XRT position (J.P. Osborne et al. GCN Circ. 22179) is detected in the initial UVOT exposures. There is marginal evidence for brightening in the white filter. The revised source position is RA(J2000)=11:09:39.547 Dec.(J2000)=-12:35:17.93. This position is within the XRT error circle and is consistent with the VLT/X-shooter optical position (L. Izzo et al. GCN Circ. 22180). Preliminary detections using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 154 303 147 18.10 +/- 0.08 white 3812 3849 36 17.70 +/- 0.09 u 312 390 78 17.78 +/- 0.18 v 4499 4698 197 18.22 +/- 0.15 b 3607 3807 197 18.45 +/- 0.09 uvw1 4908 5108 197 17.13 +/- 0.09 uvm2 4703 4903 197 17.11 +/- 0.11 uvw2 4294 4494 197 16.96 +/- 0.10 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.05 in the direction of the burst (Schlegel et al. 1998), nor from any contribution of the host galaxy. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22182 SUBJECT: GRB 171205A: RATIR Optical and NIR Observations DATE: 17/12/05 15:10:17 GMT FROM: Nat Butler at Az State U Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report: We observed the field of GRB 171205A (D'Elia, et al., GCN 22177) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2017/12 5.40 to 2017/12 5.53 UTC (2.15 to 5.36 hours after the BAT trigger), obtaining a total of 1.44 hours exposure in the r and i bands and 0.71 hours exposure in the Z and Y bands. In comparison with the USNO-B1 and 2MASS catalogs, we detect and obtain the following photometry for the source reported by Izzo et al. (GCN 22180): r = 18.30 +/- 0.05 i = 18.13 +/- 0.02 Z = 18.35 +/- 0.05 Y = 18.13 +/- 0.05 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22183 SUBJECT: GRB 171205A: Swift-XRT refined Analysis DATE: 17/12/05 16:08:33 GMT FROM: Phil Evans at U of Leicester J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), P.A. Evans (U. Leicester), S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB) and V. D'Elia report on behalf of the Swift-XRT team: We have analysed 6.6 ks of XRT data for GRB 171205A (D'Elia et al. GCN Circ. 22177), from 134 s to 22.5 ks after the BAT trigger. The data comprise 238 s in Windowed Timing (WT) mode (the first 9 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Osborne et al. (GCN Circ. 22179). The light curve can be modelled with a series of power-law decays. The initial decay index is alpha=1.84 (+0.10, -0.18). At T+289 s the decay steepens to an alpha of 2.43 (+0.09, -0.08) before breaking again at T+5714 s to a final decay with index alpha=-0.16 (+0.28, -0.69). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.717 (+0.035, -0.024). The best-fitting absorption column is consistent with the Galactic value of 5.9 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.7 x 10^-11 (4.1 x 10^-11) erg cm^-2 count^-1. A summary of the WT-mode spectrum is thus: Galactic foreground: 5.9 x 10^20 cm^-2 Intrinsic column: 5.89 (+/-0.22) x 10^20 cm^-2 at z=0.0368 Photon index: 1.717 (+0.035, -0.024) If the light curve continues to decay with a power-law decay index of -0.16, the count rate at T+24 hours will be 0.025 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 9.1 x 10^-13 (1.0 x 10^-12) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00794972. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22184 SUBJECT: GRB 171205A: Swift-BAT refined analysis DATE: 17/12/05 17:49:14 GMT FROM: Amy Lien at GSFC S. D. Barthelmy (GSFC), J. R. Cummings (CPI), V. D'Elia (ASDC), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 171205A (trigger #794972) (D'Elia et al., GCN Circ. 22177). The BAT ground-calculated position is RA, Dec = 167.423, -12.599 deg which is RA(J2000) = 11h 09m 41.5s Dec(J2000) = -12d 35' 58.0" with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 46%. The mask-weighted light curve shows some weak emissions with multiple overlapping peaks that starts at ~ T-40 s and ends at ~ T+200 s. The burst went out of the BAT FOV at T+478 s. T90 (15-350 keV) is 189.4 +- 35.0 sec (estimated error including systematics). The time-averaged spectrum from T-42.23 to T+197.80 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.41 +- 0.14. The fluence in the 15-150 keV band is 3.6 +- 0.3 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+49.08 sec in the 15-150 keV band is 1.0 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level. Assuming z = 0.0368 (Izzo et al., GCN Circ. 22180) and a standard cosmology model with H_0 = 70.5 km/s/Mpc, Omega_M = 0.274, Omega_\Lambda = 0.726 (Spergel et al. 2007), the isotropic energy release Eiso (in the observed 15-150 keV band) is 5.72e+49 erg. This Eiso is similar to other low-luminosity GRBs. For example, the Eiso (in the observed 15-150 keV band) for GRB060218 is 2.57e+49 erg (assuming T90 = 2100 s based on Campana et al. 2006) and GRB100316D has Eiso >= 3.70e+49 erg (assuming T90 >= 1300 s based on Starling et al. 2011). The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/794972/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22186 SUBJECT: GRB 171205A: GMG observation DATE: 17/12/06 03:54:39 GMT FROM: Jirong Mao at Yunnan Obs J. Mao, X. Ding and J.-M. Bai (YNAO) report: We observed the field of GRB 171205A (D'Elia et al., GCN 22177) with the 2.4-meter optical telescope at Gao-Mei-Gu (GMG) station of Yunnan Observatories. Observations began from 22:45:21 UT, about 15.4 hours after the trigger. We clearlydetected the optical counterpart reported by Izzo et al. (GCN 22180). A very preliminary result was estimated as R~20.4 mag. We note that this source is in the outskirts of the host galaxy and the magnitude that we roughly measured has large uncertainty. Detailed analysis is ongoing. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22187 SUBJECT: GRB 171205A: NOEMA detection of a bright mm afterglow DATE: 17/12/06 10:26:44 GMT FROM: Antonio de Ugarte Postigo at IAA-CSIC A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), S. Schulze (Weizmann), M. Bremer, M. Krips (IRAM), C.C. Thoene, L. Izzo, D.A. Kann, Z. Cano, K. Bensch (HETH/IAA-CSIC), S. Martin Ruiz, I. de Gregorio (ALMA), S. Kim (PUC), R. Sánchez-Ramirez (INAF-IAPS), D. Malesani (DARK/NBI) report: We observed the afterglow of GRB 171205A with NOEMA at 150GHz and 90GHz starting at 3:30 UT on the 6th of December (20.2 hrs after the GRB onset). We detect a bright afterglow in 150GHz with a preliminary flux density estimate of 35-40 mJy. The coordinates of the detected source are (J2000 +/- 0.05"): R.A.: 11:09:39.52 Dec.: -12:35:18.34 We note that if the flux density is confirmed, it would be the second brightest GRB ever detected in mm/submm wavelengths, after GRB 030329 (for a review on mm/submm data of GRBs see de Ugarte Postigo et al. 2012). Further follow-up observations are encouraged. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22188 SUBJECT: GRB 171205A: LSGT optical afterglow follow-up observation DATE: 17/12/06 13:17:04 GMT FROM: Myungshin Im at Seoul Nat U Changsu Choi, Myungshin Im (CEOU/SNU), on behalf of a larger collaboration We observed the field of GRB 171205A (D'Elia et al., GCN 22177) with SNUCAM-II (Choi & Im 2017, JKAS, 50, 71) on the 0.43m Lee Sang Gak Telescope (LSGT; Im et al. 2015, JKAS, 48. 207) at the Siding Spring Observatory in Australia. The observation started at about 9 hours after the BAT alert, using r, i, z (broad-band), m425, m475, m525, m575, and m625 (medium-band) filters. We clearly identify the optical afterglow in these bands, and preliminary photometry results in r, i, and z filters are reported below. Note that the photometric calibration is based on stars from the Pan-Starrs catalog in the vicinity of GRB 171205A, and systematic errors due to host galaxy subtraction uncertainty could amount to a few tenths of magnitude. Filter Mag err UT(center) r18.0 0.1 2017-12-05T16:17:17 i 18.1 0.1 2017-12-05T16:26:55 z 18.3 0.2 2017-12-05T16:36:33 Further observations and analysis are being carried out. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22189 SUBJECT: GRB 171205A: TNG NIR detections DATE: 17/12/06 15:45:49 GMT FROM: Andrea Melandri at INAF-OAB A. Melandri, P. D'Avanzo (INAF-OAB), L. di Fabrizio, C. Padilla (INAF-TNG), V. D'Elia (ASI/ASDC) report on behalf of the CIBO collaboration: We observed the field of GRB 171205AA (D'Elia et al. GCN 22177) with the 3.6m Telescopio Nazionale Galileo (TNG) equipped with NICS. Observations were carried out in the near-infrared with the JHK filter, starting on Dec 06 at 05:25:09 UT (~0.92 days after the burst) and consisted in a series of images for a total exposure time of 15 minutes per filter. We clearly detect the optical counterpart (Izzo et al. GCN 22180; Emery & D'Elia GCN 22181; Butler et al. GCN 22182; Mao et al. 22186; de Ugarte Postigo et al. GCN 22187; Choi et al. GCN 22188) in each filter. In our preliminary analysis the source is detected with a magnitude of J = 16.7 +/- 0.1 at a mid time of 0.922 days from the burst event (calibrated against nearby stars reported in the 2MASS catalogue). Further observations are planned. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22190 SUBJECT: GRB 171205A: GOTO detection of the optical counterpart DATE: 17/12/06 16:56:54 GMT FROM: Rhaana Starling at U of Leicester D.Steeghs, R.Cutter, K.Ulaczyk, D.Pollacco, R.West, A.Levan, J.Lyman, P.Chote, J.McCormac, K.Wiersema (U. Warwick) G.Ramsay (Armagh O.) R.Starling, P.O'Brien, R.Eyles (U. Leicester) D.K.Galloway, E.Rol, E.Thrane, K.Ackley, A.Casey (Monash U.) V.Dhillon, M.Dyer, S.Littlefair, E.Daw, J.Mullaney, L.Makrygianni, J.Maund (U. Sheffield) S.Poshyachinda, S.Aukkaravittayapun, U.Sawangwit, S.Awiphan, D.Mkrtichian (NARIT) report on behalf of the GOTO collaboration: The Gravitational-wave Optical Transient Observer observed the field of GRB 171205A (trigger=794972, D'Elia et al. GCN Circ. 22177) from Roque de los Muchachos Observatory beginning at 2017-12-06T04:24:31 UT, 21.07 hours since burst, in several wide-band filters. In a combined L-band image (400-700nm passband), with a total exposure time of 1440s at a mid-time 04:57:38 UT, 21.36 hours since burst, we detect the optical counterpart (Selsing et al. GCN Circ. 22180; Emery & D'Elia GCN Circ. 22181; Butler et al. GCN Circ. 22182; Mao et al. GCN Circ. 22186; Choi & Im GCN Circ. 22188) with a preliminary magnitude of V=18.95 +/- 0.15 based on a comparison to APASS V-band calibrators. Galaxy contamination is likely leading to an additional systematic uncertainty. An image can be viewed here: www.arm.ac.uk/~gar/GRB171205A-goto.jpg Further observations are scheduled. GOTO is operated at the La Palma observing facilities of the University of Warwick on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT) and the Instituto de Astrofísica de Canarias (IAC) (https://goto-observatory.org) GOTO Observatory goto-observatory.org The first GOTO dome at Roque de Los Muchachos observatory on La Palma. About. The Gravitational-wave Optical Transient Observer (GOTO) is a project to identify ... //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22191 SUBJECT: Possible blackbody component in the X-ray spectrum of GRB171205A DATE: 17/12/06 17:31:56 GMT FROM: Sergio Campana at INAF-OAB S. Campana (INAF-OAB), A. Beardmore (U. Leicester), A. D'Ai (INAF-IASFPA), V. D'Elia (ASDC), P. Evans (U. Leicester), J. Kennea (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), R.L.C. Starling (U. Leicester) report on a preliminary analysis of the Swift XRT data. Swift XRT started observing GRB171205A (D'Elia et al. 2017, GCN 22177) 145 s after the trigger. XRT detected a bright X-ray source decreasing from ~80 c/s to ~10 c/s from 150 s to 400 s, remaining in Windowed Timing (WT) mode (Kennea et al. 2017, GCN 22183). The hardness ratio light curve does not imply appreciable spectral variations during this time interval. We fit the WT spectrum binned to 20 counts per energy bin with an absorbed power law (with the column density fixed to 5.9e20 cm-2, Willingale et al. 2013, MNRAS 431 394). We obtain a reduced chi2=1.23 (239 degrees of freedom, dof, and 9e-3 null hypothesis probability, nhp). The inclusion of an intrinsic absorption component at the GRB redshift (z=0.0368, Izzo et al. 2017, GCN 22180) does not improve the fit, rather we can only put a 90% confidence level upper limit of N_H(z)<0.3e20 cm-2. Given the relatively low nhp of the fit we include a soft blackbody component. The fit improves considerably with kT_BB=0.10+-0.02 keV (90% c.l.) and equivalent radius R_BB~5e11 cm (for a source distance of 163 Mpc). The fit is good with a reduced chi2=1.09 (237 dof and 0.15 nhp). F-test provides a probability for a chance improvement of 6e-8. The 0.3-10 keV blackbody contribution to the total flux is ~4%. We checked that the fit does not improve using different values for the Galactic column density (NH_DL=4.82e20 cm-2 or NH_Kalberla=4.91e20 cm-2), reaching similar results. Using a spectrum made from grade 0 events does not change the results and the blackbody component is still significant. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22192 SUBJECT: GRB 171205A: SMARTS optical/IR afterglow observations DATE: 17/12/06 20:08:38 GMT FROM: Bethany Cobb at GWU B. E. Cobb (GWU), reports: Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained optical/IR imaging of the error region of GRB 171205A (GCN 22177, D'Elia et al.) with a mid-exposure time of about 24.5 hrs post-burst (2017-12-06 07:50 UT). Total summed exposure times amounted to 15 min in V and I and 12 min in J and K. The afterglow of GRB 171205A (e.g. GCN 22179, Osborne et al.; GCN 22180, Izzo et al.; GCN 22181, Emery et al.) was detected with the following preliminary magnitudes: V mag = 18.5 +/- 0.1 I mag = 17.7 +/- 0.1 J mag = 17.6 +/- 0.1 K mag = 16.2 +/- 0.1 (Optical photometry is calibrated against Landolt standard stars and IR photometry is calibrated against 2MASS stars in the field.) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22193 SUBJECT: GRB 171205A: CHILESCOPE optical observations DATE: 17/12/06 20:57:10 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), A. Pozanenko (IKI), E. Mazaeva (IKI), M. Krugov (AFIF) report on behalf of IKI-GW follow-up collaboration: We observed the field of GRB 171205A (D'Elia et al., GCN 22177) with RC-1000 1m telescope of CHILESCOPE observatory. The observations carried out in a clear filter starting on Dec. 06 (UT) 06:46:47. The afterglow of GRB 171205A (e.g. Osborne et al., GCN 22179; Izzo et al., GCN 22180; Emery et al., GCN 22181) is clearly detected. Preliminary photometry is following. Date UT start t-T0 Filter Exp. OT Err. (mid, days) (s) 2017-12-06 06:46:47 1.00122 CR 3600 18.20 0.07 The photometry is based on several nearby USNO-B1.0 stars (R2 magnitudes). USNO-B1.0 RA Dec R2 0774-0291882 11:09:46.28 -12:35:02.8 17.25 0773-0296803 11:09:34.42 -12:37:07.2 16.58 0774-0291827 11:09:37.14 -12:32:33.8 16.45 0774-0291826 11:09:36.63 -12:34:12.4 16.40 0774-0291864 11:09:43.12 -12:33:49.8 16.30 0774-0291938 11:09:56.38 -12:35:37.7 16.40 0773-0296901 11:09:57.46 -12:36:29.0 15.34 Finding chart can be found at http://grb.rssi.ru/GRB171205A/GRB171205_RC1000-171206.png //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22194 SUBJECT: GRB 171205A: Host galaxy photometric properties DATE: 17/12/06 21:55:57 GMT FROM: Daniel Perley at Liverpool JMU D. A. Perley and K. Taggart (LJMU) report: We downloaded public, pre-explosion survey data covering the field of GRB 171205A (D'Elia et al., GCN 22177) from a number of public archives: GALEX (Martin et al. 2005, ApJL 619 1), Pan-STARRS 1 (Chambers et al. 2016, arXiv:1612.05560), and 2MASS (Skrutskie et al. 2006, 131 1163). Photometry of the presumed host galaxy (2MASX J11093966-1235116; Izzo et al., GCN 22178) was obtained from the relevant photometric catalogs for 2MASS (Huchra et al. 2012, ApJS 199 26) and GALEX (Bianchi et al. 2011, MNRAS 411 2770). For Pan-STARRS 1, we performed elliptical aperture photometry on the images ourselves (using a semimajor axis of 19.35" and axis ratio 0.6) using PS1 field stars for calibration. We fit the combined SED (including 10 filters: GALEX FUV and NUV, Pan-STARRS g, r, i, z, and y, and 2MASS J, H, and Ks) using the SED fitting package LePHARE (Arnouts et al. 1999, MNRAS 310 540; Ilbert et al. 2006, A&A 457 841). A redshift of z=0.037 was assumed (Izzo et al., GCN 22180), and Galactic foreground extinction was taken to be E(B-V)=0.045 (Schlafly et al. 2011; ApJ 737 103). We obtain a stellar mass of log10(M/Msun) = 10.1 +/- 0.1 and a star-formation rate of SFR = 3 +/- 1 Msun/yr. This host mass is much larger than that of any other low-redshift GRB with a confirmed SN counterpart. The next-most-massive SN/GRB host is that of GRB 120422A (SN 2012bz), with log10(M)~9.0. In contrast, the majority of low-z (z<0.4) long-duration (>2s) GRBs with no unambiguous observed SNe are in massive hosts similar to this event. These include GRBs 060505 (Fynbo et al. 2006, Nature 444 1047), 051109B (Perley et al., GCN 5387), 050219A (Rossi et al. 2014, A&A 572), 050826 (Mirabal et al. 2007, ApJ 661, 127), 080517 (Stanway et al. 2015, MNRAS 226 3911), and possibly 150518A (cf GCN 17903, Pozanenko et al). In many of these cases an SN was not searched for to deep limits, and others could be attributed to host extinction, an ambiguous duration possibly consistent with the "short" GRB class, or confusion of a high-z GRB with a foreground galaxy. Nevertheless, it remains possible that host mass (and perhaps metallicity) is closely connected to whether a luminous SN emerges from a GRB explosion. The very long duration, bright UV counterpart, and early spectroscopy of GRB 171205A all suggest that this is a genuine (albeit low-luminosity) long GRB and is not extinguished or at high-z, and it is in a high-mass galaxy (although its position is at the outer edge of the disk). Whether or not an SN emerges from this GRB represents an important test of the tentative host dichotomy suggested by previous events. We encourage observers to monitor the photometric evolution carefully over the coming days and obtain deep, multiband photometry and spectroscopy, especially if a clear rising SN does not emerge. [GCN OPS NOTE(15dec17: Per author's request, the first-author Kann reference was corrected to be Izzo.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22195 SUBJECT: GRB 171205A: GMG observations (2nd night) DATE: 17/12/07 07:00:13 GMT FROM: Jirong Mao at Yunnan Obs J. Mao, X. Ding and J.-M. Bai (YNAO) report: We observed the field of GRB 171205A (D'Elia et al., GCN 22177) with the 2.4-meter optical telescope at Gao-Mei-Gu (GMG) station of Yunnan Observatories, beginning from 22:04:14 UT, 6th, Dec., 2017, about 1.6 days after the trigger. We still clearly detected the optical counterpart. Some preliminary results were roughly estimated as B~20.7, V~20.0, and R~20.7 mag. The brightness might be underestimated due to poor seeing. Although the magnitudes we measured have large uncertainty, we compare our observation of the first night (Mao et al. GCN 22186), and it seems that the source has no significant fading evidence. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22196 SUBJECT: GRB171205A hyperluminal radio afterglow? DATE: 17/12/07 11:28:34 GMT FROM: Arnon Dar at Technion-Israel Inst. of Tech Dado, Dar and De Rujula report: The very bright radio afterglow^1 of the far off-axis (low luminosity) GRB171205A at the outskirts of its host galaxy^2 at redshift z=0.0368 (agular distance Da~ 150 Mpc), provides another rare opportunity, like GRBs^3 980425 and 030329, to measure the apparent hyperluminal separation of the jet-produced afterglow from the anticipated supernova, which launched it^3. The CB model relation Ep \propto Eiso^{1/3} for far off-axis GRBs^4, and its estimated isotropic energy release in the observed 15-150 keV band^5, Eiso~ 5.7E49 erg, yield, in the CB model^3, Ep~100 keV, viewing angle of @~(2/Ep(eV))^1/2~4.5 mrad, and a hyperluminal velocity^3 V~ 2c/@ ~450c. With such a hyperluminal velocity, the radio afterglow separation from the SN, which launched it, will reach ~ 200 mas! after a year, easily resolved in VLBI and VLA radio follow-up observations. If the afterglow of GRB171205A was a SN-less^6 GRB, produced by a highly relativistic jet launched in a phase transition of a neutron star (to quark star ?), the above estimate will not be valid for the separation of the radio afterglow from the GRB position, if its late-time afterglow was produced by a highly magnetized millisecond pulsar^7 (MSP). We strongly urge VLA and VLBI follow up observations of the radio afterglow of GRB171205A. 1. A. de Ugarte Postigo, et al. GCN 22187 2. L. Izzo, et al. GCN 22180 3. S. Dado, A. Dar and A. De Rujula, arXiv:1610.01985 4. S. Dado and A. Dar, arXiv:1708.04603 5. S. D. Barthelmy, et al. GCN 22184 6. D. A. Perley and K. Taggart GCN 22194 7. S. Dado, A. Dar arXiv:1710.02456 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22197 SUBJECT: GRB 171205A: LCO 1-m telescope observations DATE: 17/12/07 13:36:16 GMT FROM: Cristiano Guidorzi at Ferrara U,Italy C. Guidorzi (U. Ferrara), S. Kobayashi (LJMU), C.G. Mundell (U. Bath), A. Gomboc (U. Nova Gorica), I.A. Steele (LJMU) on behalf of a large collaboration report: We observed Swift GRB171205A (D'Elia et al. GCN 22177) on December 7, 07:21 UT (2.0 days post burst) with one of the 1-m LCO telescopes in Cerro Tololo in the SDSS ri filters. We clearly detect the optical afterglow (Izzo et al. GCN 22180; Emery et al. GCN 22181; Butler et al. GCN 22182; Mao et al. GCN 22186; Choi et al. GCN 22188; Melandri et al. GCN 22189; Steeghs et al. GCN 22190; Cobb et al. GCN 22192; Volnova et al. GCN 22193) with the following magnitudes: Mid Time     Exposure       Filter       Magnitude (AB) (days)        (s) ------------------------------------------------------- 2.0          5x120          SDSS-R        19.43 +- 0.10 2.0          5x120          SDSS-I        19.19 +- 0.10 ------------------------------------------------------- as calibrated against nearby Pan-STARRS objects. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22198 SUBJECT: GRB 171205A: GROND observations of the optical/NIR transient DATE: 17/12/07 14:42:34 GMT FROM: Sebastian Schmidl at TLS Tautenburg S. Schmidl (TLS Tautenburg) and P. Schady (MPE Garching) report: We observed the field of GRB 171205A (Swift trigger 794972; D'Elia et al., GCN 22177) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile). Observations started at 07:30 UT on December 05, 2017, 10 minutes after the GRB trigger. They were performed at an average seeing of 1.5" and at an average airmass of 1.5. We clearly detect the optical/NIR transient of GRB 171205A (Izzo et al., GCN 22180; Emery & D'Elia, GCN 22181; Butler et al., GCN 22182; Mao et al., GCN 22186; de Ugarte Postigo et al., GCN 22187; Choi et al., GCN 22188; Melandri et al., GCN 22189; Steeghs et al., GCN 22190; Cobb et al., GCN 22192; Volnova et al., GCN 22193; Guidorzi et al., GCN 22197). Based on total exposures of 66 seconds in g'r'i'z', 60 seconds in JH and 180 seconds in K at a midtime of 0.36 hours after the burst, we measure the following preliminary magnitudes and upper limits (AB magnitude system): g' = 19.1 +/- 0.1 mag, r' = 18.9 +/- 0.1 mag, i' = 18.9 +/- 0.1 mag, z' = 18.8 +/- 0.1 mag, J = 18.4 +/- 0.2 mag, H = 18.2 +/- 0.3 mag, and K > 17.6 mag. Magnitudes and upper limits are calibrated against PanSTARRS and 2MASS field stars and are not corrected for the Galactic foreground extinction corresponding to a reddening of E_(B-V)= 0.05 mag in the direction of the burst (Schlegel et al. 1998). Observations are continuing. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22199 SUBJECT: GRB 171205A: MASTER-SAAO optical observations of unusual OT DATE: 17/12/07 16:35:25 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, D.Kuvshinov, A.V.Krylov, I.Gorbunov, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D. Vlasenko Lomonosov Moscow State University, Sternberg Astronomical Institut of MSU D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias R.Podesta, C.Lopez, F. Podesta Observatorio Astronomico Felix Aguilar (OAFA), National University of San Juan, Argentina H. Levato, C. Saffe Instituto de Ciencias Astronomicas,de la Tierra y del Espacio (ICATE), San Juan, Argentina O.Gres, K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk, Irkutsk State University V.Yurkov, Yu.Sergienko Blagoveschensk Educational State University, Blagoveschensk A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory MASTER-SAAO telescope observed Swift GRB171205A (D'Elia et al., GCN Circ. 22177) since 2017-12-06 23:53:47UT. There were 20 images with 180s exposition in B and unfiltered (W=0.2B+0.8R calibrated by USNO-B1) . MASTER-SAAO auto-detection system detected optical transient ((Izzo et al. GCN 22180; Emery et al. GCN 22181; Butler et al. GCN 22182; Mao et al. GCN 22186; Choi et al. GCN 22188; Melandri et al. GCN 22189; Steeghs et al. GCN 22190; Cobb et al. GCN 22192, Schmidl et al. GCN22198) several filters. The unfriltered magnitude is about ~ 19.4 mag . We note that absolute magnitude is about -16.5. The dicovery image is available at http://observ.pereplet.ru/images/MASTERGRB171205A.jpg This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22202 SUBJECT: GRB 171205A: Continued Swift/UVOT Observations DATE: 17/12/07 17:40:15 GMT FROM: Mike Siegel at PSU/Swift MOC M. H. Siegel (PSU), P. J. Brown (Mitchell Institute, TAMU), S.W.K. Emery (UCL-MSSL) and V. D'Elia (ASDC) report on behalf of the Swift/UVOT team: The Swift/UVOT has continued observations of the optical transient in GRB 171205A (D’Elia et al., GCN Circ. 22177). We find that photometry in the optical passbands is consistent with either steady flux or slight decline, consistent with the report of Mao et al. (GCN Circ. 22195). However, all four UV passbands show a significant decay over the first day of observations. Preliminary detections using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white 155 3850 183 18.05+-0.07 white 5524 28415 1081 17.85+-0.05 white 188009 193590 703 18.58+-0.08 v 5934 22497 903 18.09+-0.08 v 46094 57628 150 18.26+-0.24 v 74068 142426 350 18.20+-0.12 b 3608 3808 196 18.69+-0.10 b 26595 27502 885 18.53+-0.06 b 38171 61189 254 18.43+-0.08 b 67064 141691 379 18.69+-0.08 u 312 391 77 17.75+-0.18 u 16032 16558 513 17.54+-0.06 u 38114 61132 254 17.66+-0.08 u 67030 141669 379 18.32+-0.09 uvm2 9466 10366 885 16.67+-0.06 uvm2 46150 57780 435 18.37+-0.15 uvm2 74102 142498 1315 18.71+-0.11 uvw1 10373 16025 1066 16.95+-0.06 uvw1 38031 61074 383 17.93+-0.10 uvw1 66981 141647 568 18.51+-0.11 uvw2 5729 28438 1098 17.06+-0.07 uvw2 40218 141597 2322 18.68+-0.08 uvw2 73989 142404 877 18.82+-0.12 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.05 in the direction of the burst (Schlegel et al. 1998), nor from any contribution of the host galaxy. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22204 SUBJECT: GRB 171205A: Detection of the emerging SN DATE: 17/12/07 18:13:58 GMT FROM: Antonio de Ugarte Postigo at IAA-CSIC A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), L. Izzo (HETH/IAA-CSIC), D.A. Kann (HETH/IAA-CSIC), C.C. Thoene (HETH/IAA-CSIC), P. Pesev (GTC), R. Scarpa (GTC), D. Perez (GTC) report on behalf of a larger collaboration: We have been monitoring the counterpart of GRB 171205A (D'Elia et al. GCN22177; Izzo et al., GCN 22180) photometrically and spectroscopically with OSIRIS at the 10.4m GTC telescope. Our latest observation consisted of 3x600s exposure using the R1000B grism, which covers the spectral range between 3700 and 7880 Angstrom. On the combined spectrum, with epoch on the 7th of December at 6:05 UT, we detect broad undulating spectral features, which are prominent between 4000 and 6000 Angstrom, superposed to the afterglow continuum, which seem to indicate the emergence of an underlying supernova component. The features include a double bump in this range, similar to what was seen for the very early spectra of SN 1998bw (Patat et al. 2001), indicating that this is probably also a broad line Ic supernova. Further information will be provided through the TNS. //////////////////////////////////////////////////////////////////////// ATEL #11038 ATEL #11038 Title: GRB 171205A: Detection of the emerging SN Author: A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), L. Izzo, D. A. Kann, C. C. Thoene (all HETH/IAA-CSIC), P. Pesev, R. Scarpa, and D. Perez (all GTC) report on behalf of a larger collaboration: Queries: deugarte@iaa.es Posted: 7 Dec 2017; 19:18 UT Subjects:Optical, Gamma-Ray Burst, Supernovae We have been monitoring the counterpart of GRB 171205A (D'Elia et al. GCN #22177; Izzo et al., GCN #22180) photometrically and spectroscopically with OSIRIS at the 10.4m GTC telescope. Our latest observation consisted of 3x600s exposure using the R1000B grism, which covers the spectral range between 3700 and 7880 Angstrom. On the combined spectrum, with epoch on the 7th of December at 6:05 UT, we detect broad undulating spectral features, which are prominent between 4000 and 6000 Angstrom, superposed to the afterglow continuum, which seem to indicate the emergence of an underlying supernova component. The features include a double bump in this range, similar to what was seen for the very early spectra of SN 1998bw (Patat et al. 2001), indicating that this is probably also a broad-lined Ic supernova. Further information will be provided through the TNS. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22205 SUBJECT: GRB 171205A: TSHAO optical observations DATE: 17/12/07 19:30:56 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), A. Pozanenko (IKI), E. Mazaeva (IKI), M. Krugov (FAPHI), I. Reva (FAPHI), A. Kusakin (FAPHI), report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 171205A (D'Elia et al., GCN 22177) with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory starting on Dec. 06 (UT) 22:2319. We took several images in R-filter. The afterglow of GRB 171205A (Izzo et al. GCN 22180; Emery et al. GCN 22181; Butler et al. GCN 22182; Mao et al. GCN 22186; Choi et al. GCN 22188; Melandri et al. GCN 22189; Steeghs et al. GCN 22190; Cobb et al. GCN 22192; Volnova et al. GCN 22193; Guidorzi et al. GCN 22197; Schmidl et al. GCN 22198; Lipunov et al. GCN 22199; Ugarte Postigo et al. GCN 22204) is marginally detected. Preliminary photometry is following. Date UT start t-T0 Filter Exp. OT Err. (mid, days) (s) 2017-12-06 22:23:19 1.63574 R 1500 20.4 0.3 The photometry is based on several nearby USNO-B1.0 stars previously used in GCN 22193. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22215 SUBJECT: GRB 171205A: UKIRT near-IR observations DATE: 17/12/09 18:18:33 GMT FROM: Tanmoy Laskar at UC Berkeley T. Laskar (NRAO / UC Berkeley), W.Fong (Northwestern University), P. Milne, and N. Smith (University of Arizona) report: "We observed GRB 171205A (D'Elia et al., GCN 22177) with the Wide Field Camera (WFCAM) mounted on the 3.8-m United Kingdom Infrared Telescope (UKIRT) on Mauna Kea beginning on 2017 December 8.595 UT (3.29 days post-burst) in the J- and K-bands. Using the quick-look pipeline ORAC-DR, we clearly detect the near-IR counterpart, consistent with the XRT and optical position (Osborne et al.; GCN 22179, Izzo et al.; GCN 22180, Emery et al.; GCN 22181). We estimate the following preliminary photometry at the position of the near-IR afterglow, calibrated to 2MASS and converted to the AB system: J(AB) = 18.5 +/- 0.1 mag K(AB) = 18.3 +/- 0.1 mag We note that these magnitudes may have a non-negligible contribution from the host galaxy. Further observations are planned to track the brightness evolution and determine the galaxy contribution. We thank Watson Varricatt and Sam Benigni for their assistance in planning and executing these observations." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22216 SUBJECT: GRB 171205A: VLA detection DATE: 17/12/09 18:19:01 GMT FROM: Tanmoy Laskar at UC Berkeley T. Laskar (NRAO / UC Berkeley), D. L. Coppejans, R. Margutti (Northwestern University), and K. D. Alexander (Harvard) report on behalf of a larger collaboration: "The VLA observed GRB 171205A (D'Elia et al.; GCN 22177) at multiple frequencies from 4.49 GHz to 16.38 GHz beginning on 2017 December 9.58 UT (4.3 days after the burst). At a mean frequency of 6 GHz, we detect a radio source with a preliminary flux density of ~ 3 mJy at RA = 11:09:39.5182 +/- 0.0001 Dec = -12:35:18.480 +/- 0.002 consistent with the Swift/XRT position (Osborne et al.; GCN 22179) and the optical position (Izzo et al.; GCN 222180, Emery et al.; GCN 22181). The spectral index is steeply rising to higher frequencies as nu^2, suggesting a self-absorbed spectrum. Follow-up observations are planned. We thank the VLA staff for rapidly scheduling and executing these service observations." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22222 SUBJECT: GMRT upper limit on GRB 171205A DATE: 17/12/10 09:20:42 GMT FROM: Poonam Chandra at TIFR Poonam Chandra (NCRA-TIFR, Stockholm University), A. J. Nayana (NCRA-TIFR), Dipankar Bhattacharya (IUCAA), S. Bradley Cenko (NASA) and Alessandra Corsi (Texas Tech University) report: We observed GRB 171205A (D'Elia et al., GCN Circ. 22177) with the Giant Metrewave Radio Telescope (GMRT) on 2017 Dec 10.07 UT at 1400 MHz band. Our preliminary analysis results in a non-detection. The 3-sigma upper limit on the GRB position (Laskar et al. GCN 22216) is 180 uJy. This could be because the radio emission may be absorbed at low frequencies. More detailed analysis of the data is in progress. More observations are planned. We thank the GMRT staff to schedule the observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22223 SUBJECT: GRB 171205A: SAO-RAS optical observations DATE: 17/12/10 10:02:37 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), A. Moskvitin (SAO RAS), A. Pozanenko (IKI) report on behalf of of larger GRB follow-up collaboration: We observed the field of GRB 171205A (D'Elia et al., GCN 22177) with Zeiss-1000 telescope of SAO-RAS Observatory starting on Dec. 09 (UT) 01:07:09. We took several images in R-filter. The afterglow of GRB 171205A (Izzo et al. GCN 22180; Emery et al. GCN 22181; Butler et al. GCN 22182; Mao et al. GCN 22186; Choi et al. GCN 22188; Melandri et al. GCN 22189; Steeghs et al. GCN 22190; Cobb et al. GCN 22192; Volnova et al. GCN 22193; Guidorzi et al. GCN 22197; Schmidl et al. GCN 22198; Lipunov et al. GCN 22199; Ugarte Postigo et al. GCN 22204) is clearly detected. Preliminary photometry is following. Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2017-12-09 01:07:09 3.79078 R 22*300 18.60 0.04 22.5 The photometry is based on several nearby USNO-B1.0 stars previously used in GCN 22193. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22224 SUBJECT: GRB 171205A: Mondy optical observations DATE: 17/12/10 10:17:25 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), E. Mazaeva (IKI) report on behalf of of larger GRB follow-up collaboration: We observed the field of GRB 171205A (D'Elia et al., GCN 22177) with AZT-33IK telescope of Sayan observatory (Mondy). We took several images in R-filter under non-optimal weathe conditions on Dec. 08 and fair condiotns on Dec. 09. The afterglow of GRB 171205A (Izzo et al. GCN 22180; Emery et al. GCN 22181; Butler et al. GCN 22182; Mao et al. GCN 22186; Choi et al. GCN 22188; Melandri et al. GCN 22189; Steeghs et al. GCN 22190; Cobb et al. GCN 22192; Volnova et al. GCN 22193; Guidorzi et al. GCN 22197; Schmidl et al. GCN 22198; Lipunov et al. GCN 22199; Ugarte Postigo et al. GCN 22204) is detected on Dec. 09. Preliminary photometry is following. Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2017-12-08 21:18:28 3.59292 R 1200 n/d n/d 18.5 2017-12-09 20:44:55 4.57936 R 3300 18.4 0.1 21.7 The photometry is based on several nearby USNO-B1.0 stars previously used in GCN 22193. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22225 SUBJECT: GRB 171205A: iTelescope optical observations DATE: 17/12/10 12:51:52 GMT FROM: Veli-Pekka Hentunen at Taurus Hill Obs,A95 Veli-Pekka Hentunen and Markku Nissinen (Taurus Hill Observatory, Varkaus, Finland) report: We have observed GRB 171205A field at iTelescope observatory (Siding Spring, Australia) using T32 0.43-m f/6.8 astrograph. The optical counterpart was detected at the position RA 11:09:39.6 and DEC -12:35:18.5. The following magnitudes were obtained from the observations using NOMAD1 0774-0294483 (V=15.610) as a comparison star: Date Tmid(UT) Filter Exp. time Mag Mag.Err. 2017-12-09 17:00:25 unfiltered 10x120s 18.1 CV 0.5 2017-12-09 17:29:30 V 5x120s 17.4 0.6 --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22226 SUBJECT: GRB 171205A: MASTER-Net OT recent photometry DATE: 17/12/10 17:15:00 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, D.Kuvshinov, A.V.Krylov, I.Gorbunov, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D. Vlasenko Lomonosov Moscow State University, Sternberg Astronomical Institut of MSU R.Podesta, C.Lopez, F. Podesta Observatorio Astronomico Felix Aguilar (OAFA), National University of San Juan, Argentina H. Levato, C. Saffe Instituto de Ciencias Astronomicas,de la Tierra y del Espacio (ICATE), San Juan, Argentina D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias O.Gres, K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk, Irkutsk State University V.Yurkov, Yu.Sergienko Blagoveschensk Educational State University, Blagoveschensk A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory MASTER Global Robotic Net (http://observ.pereplet.ru) observes Swift GRB 171205A (D'Elia et al., GCN 22177) every night at MASTER-Kislovodsk, MASTER-IAC, MASTER-SAAO . The optical counterpart (Izzo et al. GCN 22180; Emery et al. GCN 22181; Butler et al.GCN 22182; Mao et al. GCN 22186; Choi et al. GCN 22188; Melandri et al.GCN 22189; Steeghs et al. GCN 22190; Cobb et al. GCN 22192; Volnova et al. GCN 22193; Guidorzi et al. GCN 22197; Schmidl et al. GCN 22198; Lipunov et al. GCN 22199; Postigo et al. GCN 22204) preliminary photometry of last nights is the following Date UT Filter OT 2017-12-09 00:40:04.45 B 18.6+-0.2 2017-12-09 01:41:23.53 B 18.5+-0.2 2017-12-10 04:42:29.82 B 18.2+-0.2 2017-12-10 05:50:48.67 V 17.20+-0.20 2017-12-10 06:11:24.21 B 17.80+-0.24 2017-12-10 06:22:41.40 B 17.68+-0.16 2017-12-10 06:22:41.40 B 17.32+-0.19 This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22227 SUBJECT: Konus-Wind observation of GRB 171205A DATE: 17/12/10 17:31:55 GMT FROM: Dmitry Frederiks at Ioffe Institute D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline, on behalf of the Konus-Wind team, report: The long GRB 171205A (Swift-BAT trigger #794972: (D'Elia et al., GCN 22177; Barthelmy et al., GCN 22184; T0(BAT)= 07:20:43.893 UT) was detected by Konus-Wind (KW) in the waiting mode. A bayesian block analysis of the KW waiting mode data reveals a count rate increase in the interval from ~T0(BAT)-50 s to ~T0(BAT)+95 s. The detection significance in the combined G1+G2 light curve (25-360 keV) is ~10 sigma (95 s scale) while no statistically significant emission has been detected in the G3 band (360-1470 keV). The KW light curve of this burst is available at http://www.ioffe.rssi.ru/LEA/GRBs/GRB171205A/ The time-averaged 3-channel spectrum, measured from T0(BAT)-48.743 s to T0(BAT)+42.521 s, is well fit by a simple power-law (PL) model with the PL index 2.0 ± 0.18, chi2 = 0.88 for 1 dof. The burst fluence in the 20-1500 keV band is (7.8 ± 1.6)x10^-6 erg/cm^2. Assuming z = 0.0368 (Izzo et al., GCN 22180) and a standard cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.30, and Omega_Lambda = 0.70, the burst isotropic energy release E_iso is 2.4x10^49 erg (20-1500 keV, observer frame). All the quoted errors are estimated at the 1 sigma confidence level. All the presented results are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22231 SUBJECT: Correction to GCN 22184: GRB 171205A: Swift-BAT refined analysis DATE: 17/12/10 19:31:23 GMT FROM: Amy Lien at GSFC A. Y. Lien (GSFC/UMBC) reports on behalf of the BAT team: In the Swift-BAT refined analysis of GRB 171205A (Barthelmy et al. GCN Circ. 22184), we reported the incorrect Eiso for GRB 171205A due to a typo. The correct Eiso (in the observed 15-150 keV band) should be 1.10e+49 erg. We apologize for the error, and we thank Dmitry Frederiks for pointing this out. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22242 SUBJECT: GRB 171205A: JCMT SCUBA-2 sub-mm observations DATE: 17/12/12 03:03:28 GMT FROM: Ian Smith at Rice U I.A. Smith (Rice U.) and N.R. Tanvir (U. of Leicester) report: We are monitoring GRB 171205A (D'Elia et al., GCN Circ. 22177) using the SCUBA-2 sub-millimeter continuum camera on the James Clerk Maxwell Telescope. The source is well detected, as seen at longer wavelengths by NOEMA (de Ugarte Postigo et al., GCN Circ. 22187) and the VLA (Laskar et al., GCN Circ. 22216). At 3.4 days after the burst trigger, the 850 micron flux density was 30.3 +/- 2.4 mJy/beam. We thank Mark Rawlings, William Montgomerie, Giovanni Rosotti, Jim Hoge, and the JCMT staff for the prompt support of these observations that are being taken under project S17BP006. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22252 SUBJECT: GRB 171205A: ALMA observations DATE: 17/12/13 12:32:39 GMT FROM: Daniel Perley at Liverpool JMU D. A. Perley (LJMU), S. Schulze (Weizmann), and A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI) report on behalf of a larger collaboration: We observed the millimeter afterglow of GRB 171205A (D'Elia et al., GCN 22177; de Ugarte Postigo, GCN 22187) using the Atacama Large Millimeter/Submillimeter Array (ALMA). Observations were taken using the band 3 (92 GHz) and band 7 (340 GHz) receivers. The band 3 observations were carried out between 2017-12-11 09:40-10:01 UT (6.10 days after trigger) and the band 7 observations were carried out between 10:02-11:04 UT (6.13 days after trigger). In a preliminary reduction, the afterglow is strongly detected (S/N > 100) in both channels. We estimate a flux density of 28 mJy at 92 GHz and a flux of 16 mJy at 340 GHz, with calibration uncertainties of ~15% and ~25%, respectively. We expect these uncertainties to improve significantly after a full reduction. Further observations are planned. We acknowledge the support of the ALMA staff in conducting these observations rapidly, in particular Anita Richards, Andy Biggs, and Eelco van Kampen. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22258 SUBJECT: GRB 171205A: RATAN observations DATE: 17/12/16 15:59:25 GMT FROM: Sergei Trushkin at Special Astrophys. Obs.,Russia S.A. Trushkin, A.K. Erkenov, P.G. Tsybulev and N.A. Nizhelskij (SAO RAS) report: We have observed GRB 171205A (D'Elia et al.; GCN Circ. 22177) with the RATAN-600 radio telescope at 4.7 and 8.2 GHz from December 9 to December 16 2017 daily. We have detected a radio fluxes within the RA errors of the source detected with VLA (Laskar et al.; GCN Circ. 22216). The mean flux densities are equal 15 +- 2 and 19 +- 2 mJy at 4.7 and 8.2 GHz respectively. But we must notice that there is a known NVSS source J110939.0-123330 (32 mJy at 1.4 GHz), also detected in the GLEAM multi-frequency survey: J110938-123334 in the field of GRB 171205A (J110939.5-123518). We have probably detected contributions from both sources with the RATAN arcmin-beams. Thus if we subtract the fluxes from the NVSS source, using the power-law fitting of its spectrum we can estimate the refined fluxes from GRB 171205A: < 3 mJy at 4.7 GHz and 10 +- 3 mJy at 8.2 GHz for mean epoch: December 12 (MJD 58099.0), i.e. ~7.3 days after the burst. [GCN OPS NOTE(16dec17): Per GCN, the extra, submitter-supplied 5-line title-block was removed.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22264 SUBJECT: GMRT Radio detection of GRB 171205A DATE: 17/12/21 20:42:00 GMT FROM: Poonam Chandra at TIFR Poonam Chandra (NCRA-TIFR, Stockholm University), A. J. Nayana (NCRA-TIFR), Dipankar Bhattacharya (IUCAA), S. Bradley Cenko (NASA) and Alessandra Corsi (Texas Tech University) report: In our continuing follow up, we observed GRB 171205A (D'Elia et al., GCN Circ. 22177) with the Giant Metrewave Radio Telescope (GMRT) on 2017 Dec 19.07 UT at 1400 MHz band. We detect radio emission at the GRB position (Laskar et al. GCN 22216) with a flux density o 782+/-57 uJy. The map rms is 33 uJy. More observations are planned. We thank the GMRT staff to schedule the observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22270 SUBJECT: GRB 171205A: SMARTS optical/IR supernova monitoring DATE: 17/12/23 04:25:55 GMT FROM: Bethany Cobb at GWU B. E. Cobb (GWU), reports: Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained additional optical/IR imaging of the error region of GRB 171205A (GCN 22177, D'Elia et al.). At each epoch, total summed exposure times amounted to 15 min in V and I and 12 min in J and K. Between approximately 1 and 2 days post-burst, the optical/IR afterglow of GRB 171205A (GCN 22180, Izzo et al.; GCN 22181, Emery et al.; GCN 22182, Butler et al.; GCN 22186, Mao et al.; GCN 22188, Choi et al.; GCN 22189, Melandri et al.; GCN 22190, Steeghs et al.; GCN 22192, Cobb; GCN 22193, Volnova et al.; GCN 22195, Mao et al.; GCN 22197, Guidorzi et al.; GCN 22198, Schmidl & Schady; GCN 22199, Lipunov et al.; GCN 22202, Siegel et al.; GCN 22205, Volnova et al.; GCN 22215, Laskar et al.; GCN 22223, Volnova et al.; GCN 22224, Volnova et al.; GCN 22225, Hentunen & Nissinen; GCN 22226, Lipunov et al.) is clearly seen to dim. After about 6 days post-burst, however, a brightening is detected. This brightening is due to the emergence of the underlying supernova associated with GRB 171205A, and is consistent with the spectroscopic detection of this supernova by de Ugarte Postigo et al. (GCN 22204). Approximate I-band and J-band magnitudes are given below. days post-burst I mag J mag 1.02056 17.7 17.6 2.03260 18.1 17.9 4.03747 18.2 18.0 6.01435 18.1 17.6 10.98015 17.7 17.5 17.01212 17.6 17.0 (Optical photometry is calibrated against Landolt standard stars; and IR photometry is calibrated against 2MASS stars in the field. The magnitudes include afterglow and host galaxy contributions and should be considered only highly preliminary values.) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22302 SUBJECT: VLBA detection of GRB 171205A DATE: 18/01/05 18:39:30 GMT FROM: Miguel Perez-Torres at IAA-CSIC Miguel Perez-Torres (IAA-CSIC), S. Bradley Cenko (NASA), Assaf Horesh (HUJI), and Antxon Alberdi (IAA-CSIC) report: We observed GRB 171205A (D'Elia et al., GCN 22177) with the Very Long Baseline Array (VLBA) on 2017 Dec 15.53 UT and 2017 Dec 16.56 at several frequencies. We centered our observations at the VLA position of GRB 171205A (Laskar et al., GCN 22216), and imaged a region of (0.5x0.5) sq. arcsec around it. At a frequency of 4.4 GHz, we detect GRB 171205A with a preliminary peak flux density of ~2.3 mJy/beam at the following position: RA = 11:09:39.5179609 Dec = -12:35:18.459250 The (preliminary) uncertainty on the position of the peak flux density is of ~130 and ~50 microarcsec in RA and Dec, respectively. More VLBI follow-up observations of GRB171205A are on the way. We thank the NRAO staff for the time allocation and their help with the observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 22350 SUBJECT: e-MERLIN detection of GRB 171205A DATE: 18/01/16 08:29:20 GMT FROM: Miguel Perez-Torres at IAA-CSIC Miguel Perez-Torres (IAA-CSIC), J. Moldon (JBCA), E. Varenius (JBCA), R. Beswick (JBCA), Antxon Alberdi (IAA-CSIC), S. Bradley Cenko (NASA), and Assaf Horesh (HUJI) report: We observed GRB 171205A (D'Elia et al., GCN 22177) with the electronic Multi-Element Radio Linked Interferometer Network (eMERLIN) on 2017 Dec 20 (from 20.06 UT until 20.35 UT) and on 2017 Dec 21 (from 21.06 UT until 21.31 UT), for a total of 12.7 hr. The observations were carried out with a five-array telescope (Mk2, Pi, Da, De, Cm) at a central frequency of 5.1 GHz, with a bandwidth of 512 MHz. The synthesized beam was of 0.22x0.030 sq. arcsec at a position angle of 17.7 deg. We clearly detected GRB 171205A with a peak flux density of 7.9 mJy/beam. The off-source rms was of 0.05 mJy/b, and the calibration uncertainty is about 5%, for a total uncertainty in the GRB flux density of 0.4 mJy. We thank the e-MERLIN staff for the time allocation and their help with the observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27812 SUBJECT: GRB 171205A: ATCA observations of late-time radio emission DATE: 20/05/25 04:50:43 GMT FROM: James Leung at U of Sydney/VAST James Leung (University of Sydney/CSIRO), Tara Murphy (University of Sydney), Emil Lenc (CSIRO), Dougal Dobie (University of Sydney/CSIRO), David Kaplan (UWM) We have performed two observations for GRB 171205A (V. D’Elia et al., GCN Circ. 22177) centred on the optical afterglow position (L. Izzo et al., GCN Circ. 22180) with the Australia Telescope Compact Array (ATCA). The observations took place on 2020 April 12 (859 days post-burst) and 2020 May 7 (884 days post-burst) at several frequencies. We report the detections and 3-sigma limits below: Date (UTC) | Freq (GHz) | Peak Flux Density (micro-Jy/beam) ----------------------------------------------------------- 2020/04/12 | 2.1 | 708 +/- 253 2020/04/12 | 5.5 | 412 +/- 47 2020/04/12 | 9.0 | 252 +/- 27 2020/04/12 | 16.7 | 112 +/- 38 2020/04/12 | 21.2 | < 87 2020/05/07 | 2.1 | 816 +/- 287 2020/05/07 | 5.5 | 440 +/- 52 2020/05/07 | 9.0 | 237 +/- 26 2020/05/07 | 16.7 | 133 +/- 50 2020/05/07 | 21.2 | < 122 We thank CSIRO staff for supporting these observations during these especially difficult times. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 29640 SUBJECT: GRB 171205A: Continued ATCA observations DATE: 21/03/10 08:47:32 GMT FROM: James Leung at U of Sydney/VAST James Leung (University of Sydney/CSIRO), Emil Lenc (CSIRO), Tara Murphy (University of Sydney), Giancarlo Ghirlanda (INAF/Brera), Ziteng Wang (University of Sydney/CSIRO) We have been monitoring the late-time radio emission of GRB 171205A (V. D’Elia et al., GCN Circ. 22177) centred on the optical counterpart position (L. Izzo et al., GCN Circ. 22180) with the Australia Telescope Compact Array (ATCA). The observations took place on 2021 March 7 (1171 days or 3.21 years post-trigger) at 2.1, 5.5 and 9.0 GHz frequencies. We report the detections below: Date (UTC) | Freq (GHz) | Peak Flux Density (micro-Jy/beam) ----------------------------------------------------------- 2021/03/07 | 2.1 | 554 +/- 92 2021/03/07 | 5.5 | 293 +/- 35 2021/03/07 | 9.0 | 179 +/- 28 Ongoing observations are planned. We thank CSIRO staff for supporting these observations during these especially difficult times.