//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13982 SUBJECT: GRB 121123A: Swift detection of a burst with optical counterpart DATE: 12/11/23 10:17:59 GMT FROM: Scott Barthelmy at NASA/GSFC E. A. Helder (PSU), S. D. Barthelmy (GSFC), V. D'Elia (ASDC), P. A. Evans (U Leicester), F. E. Marshall (NASA/GSFC), C. J. Mountford (U Leicester), K. L. Page (U Leicester) and D. M. Palmer (LANL) report on behalf of the Swift Team: At 10:02:41 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 121123A (trigger=539358). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 307.362, -11.860 which is RA(J2000) = 20h 29m 27s Dec(J2000) = -11d 51' 34" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows a single peak structure with a duration of about 25 sec. The peak count rate was ~1200 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 10:04:44.3 UT, 123.0 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 307.3179, -11.8590 which is equivalent to: RA(J2000) = +20h 29m 16.30s Dec(J2000) = -11d 51' 32.4" with an uncertainty of 5.4 arcseconds (radius, 90% containment). This location is 155 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. The initial flux in the 2.5 s image was 1.30e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 131 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 20:29:16.31 = 307.31794 DEC(J2000) = -11:51:35.4 = -11.85983 with a 90%-confidence error radius of about 0.67 arc sec. This position is 3.0 arc sec. from the center of the XRT error circle. The estimated magnitude is 19.34 with a 1-sigma error of about 0.17. No correction has been made for the expected extinction corresponding to E(B-V) of 0.05. Burst Advocate for this burst is E. A. Helder (helder AT psu.edu). 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: 13983 SUBJECT: GRB 121123A: GMG optical observation DATE: 12/11/23 12:32:40 GMT FROM: Xiao-hong Zhao at Yunnan Obs X.-H. Zhao (YNAO), C. -J. Wang, J.-R. Mao (KASI/YNAO), J.-M. Bai (YNAO) report on behalf of a larger collaboration: We observed the field of GRB 121123A (Helder et al., GCN 13982) with 2.4m Gao-Mei-Gu (GMG) telescope. Observations started at ~1.5 hrs after the burst. The optical afterglow of this burst was detected. The preliminary magnitude was R~19.2. observation is on going. We thank the GMG staff, especially Hong-Yan Gao, and De-Qing Wang for doing these observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13984 SUBJECT: GRB 121123A: MASTER-NET optical limit DATE: 12/11/23 12:37:39 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov, D.Denisenko, A.Sankovich Sternberg Astronomical Institute, Moscow State University K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University V.Krushinski, I.Zalozhnih, A. Popov Ural Federal University, Kourovka A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA) MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Blagoveschensk was pointed to the GRB121123A 100 sec after GRB time at 2012-11-23 10:04:21.926 UT. On our first (20s exposure) set we haven`t found optical transient within SWIFT error-box (Helder et. al., GCN13982). The 5-sigma upper limit has been about 16.5 mag The field was observed at large (more than 70 deg.) zenith distance. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13985 SUBJECT: GRB 121123A: Fermi GBM observation DATE: 12/11/23 19:16:43 GMT FROM: Suzanne Foley at MPE S. Foley (UCD) reports on behalf of the Fermi GBM Team: "At 10:06:00.59 UT on 23 November 2012, the Fermi Gamma-Ray Burst Monitor triggered and located the second emission episode of GRB 121123A (trigger 375357963 / 121123421) which was also detected by the Swift/BAT (Helder et al. 2012, GCN 13982, http://gcn.gsfc.nasa.gov/notices_s/sw00539358000msbx.gif). The emission detected by GBM is contemporaneous with the UVOT observation of an afterglow candidate for GRB 121123A reported by Helder et al. The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 85 degrees. The GBM light curve consists of a single peak with a long tail with a duration (T90) of about 102 s (50-300 keV). The time-averaged spectrum from T0+3.1 s to T0+106.5 s is well fit by a Band function with Epeak = 85 (+/-3) keV, alpha = -0.25 (+/-0.09), and beta = -3.0 (+0.2/-0.3). The event fluence (10-1000 keV) in this time interval is (2.20 +/- 0.08)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+32.6 s in the 10-1000 keV band is 4.00 +/- 0.25 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13986 SUBJECT: GRB 121123A: NOT optical observations DATE: 12/11/23 21:31:18 GMT FROM: Dong Xu at DARK/NBI D. Xu, T. Kruehler, D. Malesani (DARK/NBI), G. Leloudas (OKC Stockholm and DARK/NBI) I. Ilyin (AIP), J. Clasen (NOT), P. Jakobsson (U. Iceland), J. P. U. Fynbo (DARK/NBI) report on behalf of a larger collaboration: We observed the field of GRB 121123A (Helder et al., GCN 13982) using the 2.5m Nordic Optical Telescope (NOT) equipped with StanCam. Observations started at 20:03:43 UT on 2012-11-23 (i.e., 9.972 hr after the BAT trigger) and 5x300s R-band frames were obtained with mid-time of 10.218 hr post-trigger. The afterglow is clearly detected in the stacked image at coordinates R.A.(J2000)= 20:29:16.289 Dec.(J2000)=-11:51:35.87 with R=19.65+/-0.03 mag, calibrated with the #0781-0714632 star (R1=R2=17.17 mag with a scatter of 0.3 mag) in the USNO B1 catalog. We note that our measurement is only modestly fainter than the one reported by Zhao et al. (GCN 13983) at 1.5 hr after the BAT trigger, indicating a shallow decay or an irregular light curve. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13987 SUBJECT: GRB 121123A: BOOTES-4 and IAC80 optical observations DATE: 12/11/23 22:40:22 GMT FROM: Javier Gorosabel at IAA-CSIC S. Guziy (Mykolaiv Nat. Univ.), R. Sanchez-Ramirez (IAA-CSIC), L. Monteagudo Narvion (IAC), O. Lara, M. Jelinek (IAA-CSIC), P. Kubanek (IP AS CR), Y. Fan, X. Zhao, J. Bai, C. Wang, Y. Xin (Yunnan National Astronomical Observatory), Chenzhou Cui (Beijing National Astronomical Observatory), R. Cunniffe, A.J. Castro-Tirado, J.C. Tello and J. Gorosabel (IAA-CSIC), on behalf of a larger collaboration, report: We have observed the GRB 121123A optical afterglow (GCN 13982, Helder et al.) with the 0.6m BOOTES-4/MET robotic telescope at the Lijiang Astronomical Observatory (China) and with the 0.82m IAC80 telescope (Tenerife, Spain). The afterglow is detected as follows: Tel. Date Nov To-Tgrb Texp Filter Mag(Vega) UT-start (hr) (s) -------------------------------------------------------- BOOTES-4 23.5196 2.43 5x120 r 18.87 +/- 0.15 BOOTES-4 23.5711 3.66 5x120 r 19.01 +/- 0.15 IAC80 23.7853 8.80 4x300 I 18.90 +/- 0.12 Our measurements confirm the shallow decay reported by Xu et al. (GCN 13986). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13988 SUBJECT: GRB 121123A: optical observations DATE: 12/11/24 01:50:55 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (SAO MSI, IKI), A. Stepura (UAFO), A. Matkin (UAFO), D. Erofeev (UAFO), I. Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 121123A (Helder et al., GCN 13982) with VT-50 (0.5-m) telescope and GAS-250 of UAFO/ISON-Ussuriysk observatory starting on Nov. 23 (UT) 10:10:15, i.e. 6 minutes after burst trigger. We took several unfiltered images of 30 s. We do not detect detect afterglow (Helder et al., GCN 13982; Zhao et al., GCN 13983) in a stacked images. Preliminary photometry of a stacked image obtained with VT-50 is based on USNO-B1.0 stars (R2): T_start T0+, Filter, exposure, UL (3 sigma) (UT) mid (d) (s) 10:10:15 0.02793 none 90x30 18.1 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13989 SUBJECT: GRB 121123A: Swift-XRT refined Analysis DATE: 12/11/24 02:17:12 GMT FROM: Phil Evans at U of Leicester A. Melandri (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), G. Stratta (ASDC), J.A. Kennea (PSU), M.C. Stroh (PSU), D.N. Burrows (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), O.M. Littlejohns (U. Leicester) and E.A. Helder report on behalf of the Swift-XRT team: We have analysed 10 ks of XRT data for GRB 121123A (Helder et al. GCN Circ. 13982), from 129 s to 23.8 ks after the BAT trigger. The data comprise 669 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The refined XRT position is RA, Dec = 307.3183, -11.85898 which is equivalent to: RA (J2000): 20 29 16.39 Dec(J2000): -11 51 32.3 with an uncertainty of 3.5 arcsec (radius, 90% confidence). The late-time light curve (from T0+4.7 ks) can be modelled with a power-law decay with a decay index of alpha=0.50 (+/-0.09). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.448 (+0.023, -0.022). The best-fitting absorption column is 8.9 (+/-0.6) x 10^20 cm^-2, in excess of the Galactic value of 4.0 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 1.97 (+/-0.11) and a best-fitting absorption column of 5.8 (+2.3, -1.8) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (4.2 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 5.8 (+2.3, -1.8) x 10^20 cm^-2 Galactic foreground: 4.0 x 10^20 cm^-2 Excess significance: <1.6 sigma Photon index: 1.97 (+/-0.11) If the light curve continues to decay with a power-law decay index of 0.50, the count rate at T+24 hours will be 0.051 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.8 x 10^-12 (2.1 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/00539358. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13990 SUBJECT: GRB 121123A: Swift-BAT refined analysis DATE: 12/11/24 02:20:12 GMT FROM: Scott Barthelmy at NASA/GSFC S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), E. A. Helder (PSU), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from recent telemetry downlinks, we report further analysis of BAT GRB 121123A (trigger #539358) (Helder, et al., GCN Circ. 13982). The BAT ground-calculated position is RA, Dec = 307.334, -11.873 deg, which is RA(J2000) = 20h 29m 20.2s Dec(J2000) = -11d 52' 24.3" with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment). The partial coding was 82%. The mask-weighted light curve shows the burst starting off at a weak level at ~T-90 sec, with the triggering peak at ~T+10 sec, then a level period until ~T+200 sec with the onset of a large FRED peak extending out to ~T+700 sec. T90 (15-350 keV) is 317 +- 14 sec (estimated error including systematics). The time-averaged spectrum from T-6.34 to T+419.00 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.96 +- 0.20, and Epeak of 65.0 +- 5.1 keV (chi squared 45.4 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 1.5 +- 0.1 x 10^-5 erg/cm2 and the 1-sec peak flux measured from T+232.56 sec in the 15-150 keV band is 2.6 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.78 +- 0.04 (chi squared 101.58 for 57 d.o.f.). All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/539358/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 13991 SUBJECT: GRB 121123A: Enhanced Swift-XRT position DATE: 12/11/24 02:23:43 GMT FROM: Phil Evans at U of Leicester P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team. Using 12254 s of XRT Photon Counting mode data and 15 UVOT images for GRB 121123A, 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 = 307.31813, -11.86023 which is equivalent to: RA (J2000): 20h 29m 16.35s Dec (J2000): -11d 51' 36.8" with an uncertainty of 1.4 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: 13992 SUBJECT: GRB 121123A: GROND observations DATE: 12/11/24 03:38:49 GMT FROM: Sylvio Klose at TLS Tautenburg S. Schmidl, A. Nicuesa Guelbenzu, S. Klose (all TLS Tautenburg), and J. Greiner (MPE Garching) report on behalf of the GROND team: We observed the field of GRB 121123A (Swift trigger 539358; Helder et al., GCN 13982; Fermi trigger 375357963 / 121123421; Foley et al., GCN 13985) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPG/ESO telescope at La Silla Observatory (Chile). Observations started at 00:20 UT on Nov 24, about 15 hours after the GRB trigger. They were performed at an average seeing of 1.3" and at an average airmass of 1.9. The optical afterglow (Helder et al., GCN 13982; Zhao et al., GCN 13983; Xu et al., GCN 13986; Guziy et al., GCN 13987) is clearly detected in all bands. Based on 1500 s of total exposures in g'r'i'z' and 1200 s in JHK, we measure the following preliminary AB magnitudes at a midtime of 15.25 hrs after the burst: g' = 20.8 +/- 0.1, r' = 20.3 +/- 0.1, i' = 19.9 +/- 0.1, z' = 19.8 +/- 0.1, J = 19.2 +/- 0.1, H = 18.9 +/- 0.1, K = 18.6 +/- 0.2, calibrated against GROND zeropoints and 2MASS stars. The SED can be fit with a power law with a slope of beta = 1.2 +/ -0.1 and a g-band affected by a dropout with a redshift of z = 2.7 +/- 0.3, taking into acount a Galactic reddening along the line of sight of E_(B-V)= 0.05 mag (Schlegel et al.1998). We note that the data can also be fit with a modest host extinction and no dropout-affected g-band. At present we cannot solve this ambiguity. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14003 SUBJECT: GRB 121123A: Swift/UVOT Observations DATE: 12/11/26 22:25:09 GMT FROM: Stephen Holland at STScI S. T. Holland (STScI) and E. A. Helder (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 121123A starting 131 s after the BAT trigger (Helder et al., 2012, GCNC 13982). The refined UVOT position is RA (J2000) 20:29:16.30 = 307.31792 (deg) Dec (J2000) -11:51:35.6 = -11.85989 (deg) with an estimated uncertainty of 0.44 arcsec (radius, 90% confidence, statistical + systematic). We observe a slow decay of the optical afterglow, consistent with that reported by Xu et al., (2012, GCNC 13986). The afterglow is weakly detected in white at approximately 40 ks after the BAT trigger. However, the UVOT photometry is affected by a bright (B ~ 14 mag) star (USNO B1.0 0781-0714667) located approximately 22 arcsec north of the afterglow, so the late-time behavior of the optical afterglow's light curve requires further analysis. Preliminary UVOT photometry, and 3-sigma upper limits, for the afterglow are presented below. ------------------------------------------------------ Filter TSTART TSTOP Exposure Mag Err ------------------------------------------------------ white (fc) 131 281 147 19.43 0.15 u (fc) 289 539 246 19.35 0.23 white (fc) 869 1019 147 19.13 0.12 ------------------------------------------------------ v 619 1070 58 18.29 0.33 b 546 1169 58 19.12 0.29 u 695 1145 39 18.58 0.32 uvw1 669 18,011 2137 >21.5 uvm2 645 17,104 1376 >21.3 uvw2 595 22,980 1376 >21.5 white 570 590 19 >19.7 ------------------------------------------------------ The detection in the UVOT u band, combined with the non-detection in the UVOT uvw1 band, is consistent with GRB 121123A having a redshift of approximately 1.5 < z < 3.4. The quoted magnitudes and upper limits have not been corrected for the Galactic extinction along the line of sight to this burst of E_{B-V} = 0.05 mag (Schlafly et al. 2011, ApJS, 737, 103). The photometry is in the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14006 SUBJECT: GRB 121123A: Suzaku WAM observation of the prompt emission DATE: 12/11/27 15:03:15 GMT FROM: Makoto Tashiro at Saitama U/Swift T.Yasuda, M. Tashiro, Y. Terada, W. Iwakiri, K. Takahara, M. Asahina, S. Kobayashi, A. Sakamoto, Y. Ishida, H. Ueno, S. Sugimoto (Saitama U.), M. Akiyama, N. Ohmori, E. Mochinaga, M. Yamauchi (Univ. of Miyazaki), K. Yamaoka, Y. E. Nakagawa (Waseda U.), Y. Hanabata, T. Kawano, K. Takaki, R. Nakamura, Y.Tanaka, M. Ohno, Y. Fukazawa (Hiroshima U.), S. Sugita (Nagoya U.), M. Kokubun, T. Takahashi (ISAS/JAXA), Y. Urata, P. Tsai (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo), on behalf of the Suzaku WAM team, report: The long GRB 121123A (Helder et al., GCN 13982; Zhao et al., GCN 13983; Yurkov et al., GCN 13984; Foley, GCN 13985; Xu et al., GCN 13986; Guziy et al., GCN 13987; Volnova et al., GCN 13988; Melandri et al., GCN 13989; Barthelmy et al., GCN 13990; Evans et al., GCN 13991; Schmidl et al., GCN 13992) was detected by the the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 10:06:00 UT (=T0). The observed light curve shows a single peak followed by a long weak tail seen up to T0+74 s with a duration (T90) of about 73 seconds. The fluence in 100 - 1000 keV was 7.72 (+0.44/-7.11) x 10-6 erg/cm^2. The 1-s peak flux measured from T0+33 s was 0.74 (+0.54/-0.34) photons/cm^2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0+1 s to T0+74 s is well fitted by a single power-law with a photon index of 3.29 (+0.64/-0.50) (chi2/d.o.f = 4.7/11). The light curves with 1-sec time resolution for this burst will be appeared at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14088 SUBJECT: GRB 121123A: NIKA (New IRAM KID Arrays) millimetre observations at the 30-m Pico Veleta telescope DATE: 12/12/16 09:29:40 GMT FROM: Alessandro Monfardini at CNRS,Grenoble A. Monfardini (I. Néel, Grenoble), F.-X. Désert (IPAG, Grenoble), N. Ponthieu (IPAG, Grenoble), R. Adams (LPSC, Grenoble), M. Calvo (I. Néel, Grenoble), J. Macias-Perez (LPSC, Grenoble), A. Catalano (LPSC, Grenoble), S. Leclercq (IRAM, Grenoble), P. Mauskopf (Arizona State U. & Cardiff U.), A. Benoit (I. Néel, Grenoble), on behalf of the NIKA collaboration, report: "During a technical run, we observed the position of GRB 121123A (E. A. Helder et al., GCN 13982) with the NIKA instrument being commissioned at the IRAM 30-m at Pico Veleta. Observations were accomplished between 15h and 16h UT on 24th November 2012 (mean time 29.5 hours after the burst), under poor observing conditions (tau225GHz ~ 0.35) and at relatively low elevation (35 deg). In roughly 40 minutes effective time on source, we do not detect the afterglow at the position given by D. Xu et al., GCN 13986. The following 3-sigma upper limits were derived: U.L. 3 mJy at 150 GHz (99.7% C.L.) U.L. 40 mJy at 240 GHz (99.7% C.L.), strongly limited by unstable weather conditions NIKA is a multi-hundred-pixels dual-band continuum instrument operating simultaneously at central frequencies of 150 GHz (bandwidth 40 GHz) and 240 GHz (bandwidth 60 GHz). It is the first instrument based on the intrinsically multiplexable KID (Kinetic Inductance Detectors) technology installed permanently at a telescope. For more information about the instrument and the future project NIKA-2, see A. Monfardini et al., ApJS 194, Issue 2, id. 24 (2011). We thank the IRAM Granada and Grenoble staff for their outstanding support before, during and after the NIKA run." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 14200 SUBJECT: GRB 121123A: optical observations DATE: 13/02/13 16:34:45 GMT FROM: Alexei Pozanenko at IKI, Moscow Yu. Krugly (Institute of Astronomy of Kharkiv National University), R.Inasaridze, O. Kvaratskhelia(Abastumani Astrophysical Observatory), I. Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 121123A (Helder et al., GCN 13982) with AC-32 (0.7m Maksutov) telescope of Abastumani Observatory, starting on Nov. 23 (UT) 15:18. We took several unfiltered images of 180 s exposure. We clearly detected the afterglow (Helder et al., GCN 13982; Zhao et al., GCN 13983) in every single image. The photometry of the stacked images is based on USNO-B1.0 stars (R2): Start, T0+, Filter, Exp., OT (UT) (mid),days 15:18:28 0.2229 none 4x180 19.01 +/- 0.10 15:33:10 0.2337 none 4x180 18.96 +/- 0.09 15:48:15 0.2448 none 4x180 18.88 +/- 0.08 16:02:57 0.2551 none 4x180 19.17 +/- 0.11 16:02:57 0.2642 none 4x180 18.94 +/- 0.10 16:28:40 0.2729 none 4x180 19.06 +/- 0.11