//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27915 SUBJECT: GRB 200612A: Swift detection of a burst DATE: 20/06/12 05:06:28 GMT FROM: David Palmer at LANL E. Sonbas (Adiyaman Univ.), C. Gronwall (PSU), N. J. Klingler (PSU), H. A. Krimm (NSF), A. Y. Lien (GSFC/UMBC), K. L. Page (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU) and A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift Observatory Team: At 04:39:37 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 200612A (trigger=977310). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 302.681, -45.357 which is RA(J2000) = 20h 10m 43s Dec(J2000) = -45d 21' 24" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex structure with a duration of about 40 sec. There is possible lower-level activity out to T+180s. The peak count rate was ~1400 counts/sec (15-350 keV), at ~1 sec after the trigger. The XRT began observing the field at 04:41:04.7 UT, 87.7 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 302.7017, -45.3343 which is equivalent to: RA(J2000) = 20h 10m 48.41s Dec(J2000) = -45d 20' 03.5" with an uncertainty of 5.1 arcseconds (radius, 90% containment). This location is 97 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 2.13e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 95 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 0.03. We note that Fermi-GBM sees a GRB in a similar location at T+10 minutes, (trigger 613630183) which may be extended activity of the same source. At that time, BAT had slewed away from the source. Burst Advocate for this burst is E. Sonbas (edasonbas AT yahoo.com). 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/) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27916 SUBJECT: Swift GRB200612.19: Global MASTER-Net observations report DATE: 20/06/12 05:07:18 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov, D. Cheryasov (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University) MASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB200612.19 (trigger No 977310,20h 10m 43.44s , -45d 21m 25.2s, R=0.05) errorbox 10 sec after notice time and 495 sec after trigger time at 2020-06-12 04:47:52 UT, with upper limit up to 18.3 mag. The observations began at zenith distance = 33 deg. The sun altitude is -81.6 deg. The galactic latitude b = -33 deg., longitude l = 355 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1380088 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 546 | MASTER-OAFA | C | 100 | 18.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27917 SUBJECT: Swift GRB200612.19: Global MASTER-Net OT detection DATE: 20/06/12 05:17:43 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa, A.Kuznetsov, A.V. Krylov, I. Gorbunov, D. Vlasenko, F. Balakin Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University R. Podesta, Carlos Lopez and F. Podesta Observatorio Astronomico Felix Aguilar (OAFA) Hugo Levato Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory V. Yurkov, A. Gabovich, Yu. Sergienko Blagoveschensk Educational State University, Blagoveschensk K. Ivanov, O. Gres, N.M. Budnev, S.Yazev, O. Chuvalaev, V. Poleshchuk Irkutsk State University 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 MASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the GRB200612.19 19 sec after notice time and 495 sec after trigger time at 2020-06-12 04:47:52 UT. On our 4-th (180s exposure) set , obtained 960 sec after tigger time at 2020-06-12 04:55:38 UT, we found 1 optical transient within Swift error-box (ra=302.679 dec=-45.3569 r=0.05) brighter than 18.2. T-Tmid Date Time Expt. Ra Dec Mag ---------|---------------------|-------|-----------------|-----------------|------- 1050 2020-06-12 04:55:38 180 (20h 10m 48.64s , -45d 20m 06.7s) 17.9 The 5-sigma upper limit has been about 18.2mag The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27919 SUBJECT: GRB 200612A: BOOTES-3/YA optical upper limit DATE: 20/06/12 17:02:23 GMT FROM: Youdong HU at IAA-CSIC Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado (IAA-CSIC), I. Carrasco and C. Perez del Pulgar (Univ. de Malaga), M. D. Caballero-Garcia (ASU-CAS, CZ) and R. Querel (NIWA), on behalf of a larger collaboration, report: The 60cm BOOTES-3/YA robotic telescope at NIWA Lauder in Otago (New Zealand) responded to the Swift trigger of GRB 200612A (Sonbas et al. GCNC 27915). The first image (clear filter) was obtained starting at 09:51:32 UT(~ 5.2 hr after trigger). In the co-added image (20 exposures 60s each), no source is found at the position reported by Swift/XRT (Sonbas et al. GCNC 27915) and MASTER-Net (Lipunov et al. GCNC 27917) down to 20.3 mag. We thank the staff at NIWA for its excellent support. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27920 SUBJECT: GRB 200612A: Late Optical Maximum Deteted by MASTER DATE: 20/06/12 18:55:38 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs N.Tiurina, Lomonosow NSU We find very late OT (Lipunov et al., GCN 27917) maximum ~17.5 around 2020-06-12 04:59:09 UT . This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27921 SUBJECT: GRB 200612A: Enhanced Swift-XRT position DATE: 20/06/12 20:11:58 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 2651 s of XRT Photon Counting mode data and 7 UVOT images for GRB 200612A, 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 = 302.70204, -45.33550 which is equivalent to: RA (J2000): 20h 10m 48.49s Dec (J2000): -45d 20' 07.8" with an uncertainty of 1.5 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: 27922 SUBJECT: Konus-Wind observation of ultra-long GRB 200612A DATE: 20/06/12 20:13:01 GMT FROM: Dmitry Svinkin at Ioffe Institute D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, M. Ulanov, A. Tsvetkova, A.Lysenko, A. Ridnaia, and T. Cline on behalf of the Konus-Wind team, report: The ultra-long GRB 200612A (Swift-BAT detection Sonbas et al., GCN 27915; MASTER OT detection: Lipunov et al., GCN 27917) was detected by Konus-Wind in the waiting mode. The burst light curve shows four emission episodes in the interval from ~T0(BAT) s to ~T0(BAT)+1020 s. The K-W light curve of this burst is available at http://www.ioffe.ru/LEA/GRBs/GRB200612A/ As observed by Konus-Wind, the burst had a fluence of 4.08(-0.34,+1.04)x10^-5 erg/cm2 and a 2.944-s peak flux, measured from ~T0(BAT)+478.8 s, of 2.75(-0.62,+0.85)x10^-7 erg/cm2/s (both in the 20 - 1500 keV energy band). The K-W 3-channel time-integrated spectrum (from ~T0(BAT) s to ~T0(BAT)+1020 s) is well described by a cutoff power-law model with alpha = -1.0(-0.2,+0.3) and Ep= 253(-65,+95) keV. All the quoted errors are estimated at the 1 sigma confidence level. All the presented results are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27923 SUBJECT: GRB 200612A: Swift-XRT refined Analysis DATE: 20/06/13 00:13:52 GMT FROM: Phil Evans at U of Leicester A. D'Ai (INAF-IASFPA), J. D. Gropp (PSU), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), A. Melandri (INAF-OAB), T. Sbarrato (INAF-OAB) and E. Sonbas report on behalf of the Swift-XRT team: We have analysed 7.4 ks of XRT data for GRB 200612A (Sonbas et al. GCN Circ. 27915), from 93 s to 63.5 ks after the BAT trigger. The data comprise 281 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Osborne et al. (GCN Circ. 27921). The late-time light curve (from T0+3.7 ks) can be modelled with a power-law decay with a decay index of alpha=1.37 (+/-0.09). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.07 (+/-0.05). The best-fitting absorption column is 9.1 (+2.3, -2.1) x 10^20 cm^-2, in excess of the Galactic value of 3.7 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 2.06 (+0.19, -0.17) and a best-fitting absorption column of 5.7 (+4.1, -2.0) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.1 x 10^-11 (3.6 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 5.7 (+4.1, -2.0) x 10^20 cm^-2 Galactic foreground: 3.7 x 10^20 cm^-2 Excess significance: <1.6 sigma Photon index: 2.06 (+0.19, -0.17) If the light curve continues to decay with a power-law decay index of 1.37, the count rate at T+24 hours will be 0.010 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.2 x 10^-13 (3.7 x 10^-13) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00977310. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27924 SUBJECT: GRB 200612A: Swift-BAT refined analysis DATE: 20/06/13 01:19:49 GMT FROM: Sibasish Laha at GSFC C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL), T. Sakamoto (AGU), E. Sonbas (Adiyaman Univ.), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 200612A (trigger #977310) (E. Sonbas et al., GCN Circ. 27915). The BAT ground-calculated position is RA, Dec = 302.691, -45.354 deg which is RA(J2000) = 20h 10m 45.8s Dec(J2000) = -45d 21' 12.7" with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 96%. The mask weighted light curve shows a complex structure. The overall structure starts at ~T-20 s and lasts till ~T+200 s. T90 (15-350 keV) is 171.48 +- 19.74 sec (estimated error including systematics). The time-averaged spectrum from T-11 to T+193 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.34 +- 0.09. The fluence in the 15-150 keV band is 3.8 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+4.03 sec in the 15-150 keV band is 0.7 +- 0.2 ph/cm2/sec. 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/977310/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27925 SUBJECT: Draft Circular for GRB 200612A DATE: 20/06/13 02:43:08 GMT FROM: Sam LaPorte at PSU Hey all, There's very little data to look at here but it's a conclusive nondetection, so I'll be sending out the upper limits auto-circular shortly barring any comments. -Sam GRB 200612A: Swift/UVOT Upper Limits S. J. LaPorte (PSU) and E. Sonbas (Adiyaman Univ.) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 200612A 96 s after the BAT trigger (Sonbas et al., GCN Circ. 27915). No optical afterglow consistent with the optical position (Lipunov et al. GCN Circ. 27917) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 96 245 147 >20.6 white 96 245 147 >20.6 u 308 375 67 >19.2 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27929 SUBJECT: GRB 200612A: Swift/UVOT Upper Limits DATE: 20/06/13 12:43:45 GMT FROM: Sam LaPorte at PSU GRB 200612A: Swift/UVOT Upper Limits S. J. LaPorte (PSU) and E. Sonbas (Adiyaman Univ.) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 200612A 96 s after the BAT trigger (Sonbas et al., GCN Circ. 27915). No optical afterglow consistent with the optical position (Lipunov et al. GCN Circ. 27917) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 96 245 147 >20.6 white 96 245 147 >20.6 u 308 375 67 >19.2 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27934 SUBJECT: GRB 200612A: Fermi GBM detection DATE: 20/06/13 20:50:23 GMT FROM: Christian Malacaria at NASA-MSFC/USRA C. Malacaria (NASA-MSFC/USRA), E. Burns (NASA-GSFC) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: At 04:49:38.68 UT on June 06 2020, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 200612A (trigger 613630183/200612201), which was also detected by the Swift (Osborne et al. 2020, GCN 27921) and Konus-Wind (Sonbas et al. 2020, GCN 27915; Svinkin et al. 2020, GCN 27922). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 50 degrees. The GBM light curve shows multiple pulses with a duration (T90) of about 88 s (50-300 keV). The GBM light curve also shows evidence of emission preceding the trigger time, in agreement with the super-long GRB classification by Konus-Wind. The time-averaged spectrum from T0-214 s to T0+89 s is best-fit by a power-law with a photon index of -1.80 +/- 0.02. The event fluence (10-1000 keV) in this time interval is (4.187 +/- 0.109)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+52 s in the 10-1000 keV band is 2.8 +/- 0.2 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/