GRB240805B

This page lists all entries on GRB240805B in GRBweb

Summary IPN Swift GCN 37043 GCN 37050 GCN 37051 GCN 37052 GCN 37053 GCN 37055 GCN 37057 GCN 37059 GCN 37060 GCN 37062 GCN 37072 GCN 37074 GCN 37076 GCN 37084 GCN 37086 GCN 37192

Summary table
Variable Value Source
T0 14:28:54 UTC GCN_circulars,Swift Det
ra 254.2153° Swift
decl 18.3175° Swift
pos_error 6.21e-04° Swift
GBM_located False
mjd 60527.60340277778 GCN_circulars,Swift Det
IPN table
GRB_name GRB240805B
ra 254.2375°
decl 18.3167°
pos_error 5.00e-02°
Swift table
GRB_name GRB240805B
t_trigger 14:28:54 UTC
ra 254.2153°
decl 18.3175°
pos_error 6.21e-04°
GCN 37043 table
GRB_name GRB240805B
GCN_number 37043
Detection_method Swift Det
t_trigger 14:28:54 UTC
ra 254.2390°
decl 18.3230°
Circular_text TITLE: GCN CIRCULAR NUMBER: 37043 SUBJECT: GRB 240805B: Swift detection of a burst DATE: 24/08/05 14:51:03 GMT FROM: David Palmer at LANL M. A. Williams (PSU), S. Dichiara (PSU), R. Gupta (NASA GSFC), J. A. Kennea (PSU) and D. M. Palmer (LANL) report on behalf of the Neil Gehrels Swift Observatory Team: At 14:28:54 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 240805B (trigger=1246989). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 254.239, +18.323 which is RA(J2000) = 16h 56m 57s Dec(J2000) = +18d 19' 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 70 sec. The peak count rate was ~2800 counts/sec (15-350 keV), at ~16 sec after the trigger. The XRT began observing the field at 14:30:12.5 UT, 78.4 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 254.2153, 18.3175 which is equivalent to: RA(J2000) = 16h 56m 51.67s Dec(J2000) = +18d 19' 03.0" with an uncertainty of 4.8 arcseconds (radius, 90% containment). This location is 83 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 87 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 0.087. Burst Advocate for this burst is M. A. Williams (mjw6837 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/)
GCN 37050 table
GRB_name GRB240805B
GCN_number 37050
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 37050 SUBJECT: GRB 240805B: JinShan optical upper limits DATE: 24/08/05 17:34:05 GMT FROM: Zipei Zhu at NAOC Z.P. Zhu, X. Liu, J. An, S.Y. Fu, S.Q. Jiang, L.B. He, D. Xu (NAOC) report on behalf of a large collaboration: We observed the field of GRB 240805B detected by Swift/BAT (Williams et al., GCN 37043), using the JinShan 100cm-C telescope (100C) and 50cm-D telescope (50D) located at Altay, Xinjiang, China.The observation started at 14:55:19 UT on 2024-08-05, ~ 0.44 hr after the BAT trigger. A series of exposures were obtained in the Sloan g-, r-, i-, and z- filters. No uncataloged source is found within or around the XRT error circle (Williams et al., GCN 37043). The obtained upper limits are as follows: Telescope Tmid-T0/hr Filter Exptime Mag(AB) 100C 0.582 r 5x200s >22.0 100C 0.868 i 5x200s >22.2 100C 1.318 z 7x300s >21.5 50D 1.683 g 20x180s >22.0 We acknowledge the excellent support from S.W. Luo, M.M. Yang, Z.K. Feng, Q.C. Zhao and L.F. Huo for enabling these observations.
GCN 37051 table
GRB_name GRB240805B
GCN_number 37051
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 37051 SUBJECT: Swift GRB 240805B: Global MASTER-Net observations report DATE: 24/08/05 19:18:29 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko, G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gress, N.M. Budnev, O.Ershova (Irkutsk State University, API), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich (Blagoveschensk Educational State University) MASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB 240805B ( M. A. Williams et al., GCN 37043) errorbox 16180 sec after notice time and 16840 sec after trigger time at 2024-08-05 19:09:34 UT, with upper limit up to 17.1 mag. The observations began at zenith distance = 32 deg. The sun altitude is -19.2 deg. The galactic latitude b = 33 deg., longitude l = 38 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2551783 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 16931 | MASTER-Tavrida | C | 180 | 16.5 | 16931 | MASTER-Tavrida | C | 180 | 17.1 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.
GCN 37052 table
GRB_name GRB240805B
GCN_number 37052
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 37052 SUBJECT: GRB 240805B: LCOGT Optical Upper Limits DATE: 24/08/05 19:37:57 GMT FROM: Robert Strausbaugh at Eastern Illinois University R. Strausbaugh (Eastern Illinois University), A. Cucchiara (NASA) report on behalf of a larger collaboration: We observed the Swift GRB 240805B field (Williams et al., GCN 37043) with the LCOGT 1-meter Sinistro instrument at the South African Astronomical Observatory site, on August 5, from 18:01 to 18:34 UT (corresponding to 3.55 to 4.10 hours after the GRB trigger time) with the sdss r and i filters. We performed a series of 3x300s exposures in each band. We do not detect an uncataloged source within the XRT error region in either band. This result is consistent with other optcal upper limits (Zhu et al., GCN 37050; Lipunov et al., GCN 37051). The following 5-sigma upper limits are calculated using the PanSTARRS catalog as reference: r > 21.1 i > 20.5 These magnitudes are not corrected for galactic extinction.
GCN 37053 table
GRB_name GRB240805B
GCN_number 37053
Detection_method Swift-XRT Det
ra 254.2125°
decl 18.3196°
Circular_text TITLE: GCN CIRCULAR NUMBER: 37053 SUBJECT: GRB 240805B: Enhanced Swift-XRT position DATE: 24/08/05 23:15:38 GMT FROM: Phil Evans at U of Leicester M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team. Using 1007 s of XRT Photon Counting mode data and 3 UVOT images for GRB 240805B, 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 = 254.21255, +18.31958 which is equivalent to: RA (J2000): 16h 56m 51.01s Dec (J2000): +18d 19' 10.5" with an uncertainty of 3.1 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.
GCN 37055 table
GRB_name GRB240805B
GCN_number 37055
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 37055 SUBJECT: GRB 240805B: BTA optical afterglow candidate DATE: 24/08/06 00:45:23 GMT FROM: Moskvitin Alexander at SAO RAS A. Moskvitin, D. Oparin, A Vinokurov (SAO RAS), N. Pankov (HSE, IKI) and A. Pozanenko (IKI) report: We observed the field of the GRB 240805B (Williams et al., GCN 37043) with the BTA 6-meter telescope of SAO RAS equipped with the focal reducer Scorpio-I. We obtained 7 x 120 + 30 sec images on August 5, 2024-08-05T19:31:44 -- 2024-08-05T20:10:44 (t_mid - T0 = 8.372 hours). Within the enhanced XRT error circle (Goad et al., GCN 37053) close to its edge we detected a single source with the coordinates (J2000): R. A. = 16:56:51.20 Dec. = +18:19:11.7 +/- 0".5 and brightness of R = 21.62 +/- 0.04 (calibrated against nearby SDSS stars, magnitudes converted with Lupton 2005 equations) and not corrected for Galactic extinction. This source is located near SDSS object J165651.21+181914.0 but significantly brighter, thus it may be GRB OT.
GCN 37057 table
GRB_name GRB240805B
GCN_number 37057
Detection_method Swift-UVOT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 37057 SUBJECT: GRB 240805B: Swift/UVOT Upper Limits DATE: 24/08/06 01:35:51 GMT FROM: Mike Siegel at PSU/Swift MOC M. H. Siegel (PSU) and M. Williams (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 240805B 88 s after the BAT trigger (Williams et al., GCN Circ. 37043). No optical afterglow consistent with the XRT position (Goad et al., GCN Circ. 37053) 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 88 238 147 >20.9 u_FC 301 551 246 >19.9 white 88 1719 411 >21.6 v 630 1768 136 >19.4 b 556 1694 117 >19.7 u 301 1669 343 >20.2 w1 679 1818 136 >19.6 m2 1256 1620 39 >19.2 w2 606 1744 136 >20.1 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.087 in the direction of the burst (Schlegel et al. 1998).
GCN 37059 table
GRB_name GRB240805B
GCN_number 37059
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 37059 SUBJECT: GRB 240805B: Swift-XRT refined Analysis DATE: 24/08/06 02:27:11 GMT FROM: Phil Evans at U of Leicester K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAR), T. Sbarrato (INAF-OAB), A. Tohuvavohu (U. Toronto), D.N. Burrows (PSU), J. D. Gropp (PSU) and P.A. Evans report on behalf of the Swift-XRT team: We have analysed 8.2 ks of XRT data for GRB 240805B, from 71 s to 30.3 ks after the BAT trigger. The data comprise 4.5 ks in Windowed Timing (WT) mode (the first 6 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The late-time light curve (from T0+5.6 ks) can be modelled with a power-law decay with a decay index of alpha=1.55 (+/-0.26). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.77 (+/-0.06). The best-fitting absorption column is 1.19 (+0.21, -0.20) x 10^21 cm^-2, in excess of the Galactic value of 7.6 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.9 (+0.4, -0.3) and a best-fitting absorption column of 1.5 (+1.4, -0.7) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (4.6 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.5 (+1.4, -0.7) x 10^21 cm^-2 Galactic foreground: 7.6 x 10^20 cm^-2 Excess significance: <1.6 sigma Photon index: 1.9 (+0.4, -0.3) If the light curve continues to decay with a power-law decay index of 1.55, the count rate at T+24 hours will be 3.4 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.2 x 10^-13 (1.6 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/01246989. This circular is an official product of the Swift-XRT team.
GCN 37060 table
GRB_name GRB240805B
GCN_number 37060
Detection_method Swift-BAT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 37060 SUBJECT: GRB 240805B: NUTTelA-TAO / BSTI Optical Limits DATE: 24/08/06 06:07:28 GMT FROM: Zhanat Maksut at Nazarbayev University Z. Maksut (NU), B. Grossan (UCB, NU), T. Komesh (NU), Zh. Abdullayev (NU), M. Krugov (FAI) and E. Abdikamalov (NU) report on behalf of the Energetic Cosmos Laboratory: The Nazarbayev University Transient Telescope at Assy-Turgen Astrophysical Observatory (NUTTelA-TAO) observed the field of GRB 240805B, 0.8 h after receipt an automated GCN / BAT position alert, observing in Sloan g' and r' bands, with the Burst Simultaneous Three-Channel Imager (BSTI; Grossan, Kumar & Smoot 2019, JHEA, 32, 14). We started observations at 15:29:10 UT on 2024-08-05, 0.8 h after the BAT trigger. Observations were made in clear conditions. No source consistent with the XRT (Goad et al., GCN 37053) was detected. We report the following results: start time t-t0(h) end time UL g' UL r' exposure_time (s) ----------------------------------------------------------------------- 15:29:10 0,81 15:35:19 19.7 19.4 3x120 start time is in UT. t-t0(h) gives the time since trigger, in hours. UL gives the 5 sigma upper limit sensitivity in magnitudes, for images co-added to the given exposure time. Calibration was done with the 4 bright Pan-STARRS catalog stars on our images. ---------------------------------- NU = Nazarbayev University, Astana, Kazakhstan UCB = University of California, Berkeley, USA FAI = Fesenkov Astrophysical Institute, Almaty, Kazakhstan This research has been funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP14870504). The NUTTelA-TAO Team acknowledges the support of the staff of the Assy-Turgen Astrophysical Observatory, Almaty, Kazakhstan, and the Fesenkov Astrophysical Institute, Almaty, Kazakhstan.
GCN 37062 table
GRB_name GRB240805B
GCN_number 37062
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 37062 SUBJECT: GRB 240805B: Optical detection with 1.6m Mephisto DATE: 24/08/06 08:26:44 GMT FROM: Brajesh Kumar at SWIFAR, YNU Guowang Du (SWIFAR, YNU), Yuan Fang (SWIFAR, YNU), Yangwei Zhang (SWIFAR, YNU), Xuhui Han (NAOC), Pinpin Zhang (NAOC), Liping Xin (NAOC), Chao Wu (NAOC), Brajesh Kumar (SWIFAR, YNU), Baokun Sun (SWIFAR, YNU), Yuanpei Yang (SWIFAR, YNU), Xinzhong Er (SWIFAR, YNU), Xiangkun Liu (SWIFAR, YNU), Xiaowei Liu (SWIFAR, YNU) We did simultaneous multi-band photometric observations of GRB 240805B (Williams et al., GCN 37043) using 1.6m Multi-channel Photometric Survey Telescope (Mephisto) of Yunnan University located at Lijiang Observatory. The observations were started at (UTC) 2024-08-05 15:46:50 and multiple frames were obtained in uvgriz bands. In our preliminary analysis the OT candidate (Moskvitin et al., GCN 37055) is detected in r, i and z bands with the following magnitudes: MJD Filter Mag (AB) 60527.65751 r 20.3+-0.2 60527.66333 i 18.2+-0.04 60527.65751 z 17.8+-0.08 60527.66333 u >21.1 60527.65751 v >21.2 60527.66333 g >20.9 -----------------------------------------------------------------------------------------------------Mephisto (Multi-channel Photometric Survey Telescope) is a 1.6m wide-field multi-channel telescope, the first of its type in the world, capable of imaging the same field of view in three optical bands simultaneously. It provides real-time, high-quality colors of stellar objects. The on-site telescope assemblage and commissioning were carried out in September 2022. The first light in all three channels was achieved on 2023 December 21. -----------------------------------------------------------------------------------------------------
GCN 37072 table
GRB_name GRB240805B
GCN_number 37072
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 37072 SUBJECT: GRB 240805B: AbAO, CrAO, and Terskol optical upper limits DATE: 24/08/06 14:20:22 GMT FROM: Alexei Pozanenko at IKI, Moscow N. Pankov (HSE, IKI), A. Pozanenko (IKI), V. Rumyantsev (CrAO), R. Ya. Inasaridze (AbAO), A. Shikherin (KIAM) report on behalf of GRB-IKI-FuN: We observed the field of GRB 240805B detected by Swift (Williams et al, GCN 37043; Goad et al, GCN 37053) with AS-32 0.7-meter telescope of Abastumani observatory (AbAO) in R-filter, ZTSh 2.6-meter telescope of CrAO in R-filter, and K800 0.8-meter telescope of Terskol observatory in clear filter. The observations began on 2024-08-05 at 17:30 UT at AbAO (i.e. 3.1 hr since Swift trigger) in variable conditions. We obtain upper limits on the optical counterpart found and confirmed in (Moskvitin et al, GCN 37055; Du et al, GCN 37062): Date UT start t-T0 Exp. Filter OT Err. UL Observ./Scope (mid, days) (s) (3-sigma) 2024-08-05 17:30:52 0.14442 52x60 R n/d n/d 20.2 AbAO/AS-32 2024-08-05 19:50:58 0.24449 30*120 R n/d n/d 20.5 CrAO/ZTSh 2024-08-05 20:10:07 0.23695 44*30 CR n/d n/d 17.0 Terskol/K800 The photometry was calibrated against nearby stars of USNO-B1.0 (R2 magnitudes). The upper limits are in agreement with no detections by (Zhu et al, GCN 37050; Strausbaugh et al, GCN 37052; Siegel & Williams, GCN 37057; Maksut et al, GCN 37060).
GCN 37074 table
GRB_name GRB240805B
GCN_number 37074
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 37074 SUBJECT: GRB 240805B: JinShan optical afterglow detection DATE: 24/08/06 15:03:47 GMT FROM: Dong Xu at NAOC/CAS Z.P. Zhu, X. Liu, J. An, S.Y. Fu, S.Q. Jiang, L.B. He, D. Xu (NAOC), J.Z. Liu (XAO) report on behalf of a large collaboration: We reported JinShan optical upper limits (GCN 37050) at the Swift/XRT position of GRB 240805B (Williams et al., GCN 37043). Later on, the Enhanced Swift-XRT position was available (Goad et al., GCN 37053), which has a quite positional shift compared to the early position (Williams et al., GCN 37043). Checking the Enhanced Swift-XRT position in the JinShan images, we find the optical afterglow (e.g., Moskvitin et al., GCN 37055; Du et al., GCN 37062) is detected in the r-/i-/z- bands. Thus, the updated preliminary results are as follows: Telescope Tmid-T0/hr Filter Exptime Mag(AB) MagErr 50D 1.683 g 20x180s >21.5 - 100C 0.582 r 5x200s 20.03 0.06 100C 0.868 i 5x200s 18.79 0.02 100C 1.318 z 7x300s 18.79 0.02 We acknowledge the excellent support from S.W. Luo, M.M. Yang, Z.K. Feng, Q.C. Zhao and L.F. Huo for enabling these observations.
GCN 37076 table
GRB_name GRB240805B
GCN_number 37076
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 37076 SUBJECT: GRB 240805B Bassano Bresciano Observatory upper limit DATE: 24/08/06 15:20:26 GMT FROM: Ulisse Quadri at Bassano Bresciano Observatory U.Quadri, L.Strabla and P.Madurini (Bassano Bresciano Astronomical Observatory), Members of: AAVSO - American Association of Variable Star Observers. UAI - Unione Astrofili Italiani/GRB section. GAC - Gruppo Astrofili Cremonesi. In a large collaboration with: M.G. Dainotti (National Astronomical Observatory of Japan), Y. Niino (Tokyo University, Institute of Astronomy), K. Kalinowski (Aarhus University, Department of Physics and Astronomy), B. De Simone (Universita' degli Studi Di Salerno) report: We imaged the field of GRB 240805B detected by SWIFT (trigger num. 1246989) with the robotic telescope of (IAU station 565) Bassano Bresciano Observatory, Italy. The observations started 6.72 hour after the GRB trigger, At the end of twilight with our Newton telescope D=450 mm F/D=4.5. Weather conditions were good. We co-added 2 series of 50 exposures of 20 sec each. Start T0+ End T0+ Vlim 6.72 hour 7.02 hour 21.2 7.02 hour 7.35 hour 21.2 We did not found any optical counterpart in the error box of the XRTcandidate: M. A. Williams et al., GCN 37043; Z.P. Zhu et al., GCN 37050; V. Lipunov et al., GCN 37051; R. Strausbaugh et al., GCN 37052; A. Moskvitin et al., GCN 37055; Z. Maksut et al., GCN 37060; Guowang Du et al., GCN 37062; N. Pankov et al., GCN 37072. Magnitudes were estimated with the pan-STARRS cat. and are derived using Lupton (2005) equations. Not corrected for galactic dust extinction. Reference: http://www.osservatoriobassano.org/GRB.asp The
GCN 37084 table
GRB_name GRB240805B
GCN_number 37084
Detection_method Swift-BAT Det
ra 254.2150°
decl 18.3140°
Circular_text TITLE: GCN CIRCULAR NUMBER: 37084 SUBJECT: GRB 240805B: Swift-BAT refined analysis DATE: 24/08/06 20:26:19 GMT FROM: Rahul Gupta at NASA GSFC H. A. Krimm (NSF), S. D. Barthelmy (GSFC), R. Gupta (GSFC), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), M. J. Moss (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC), D. Sadaula (GSFC/UMBC), T. Sakamoto (AGU)(i.e. the Swift-BAT team): Using the data set from T-239 to T+1121 sec from the recent telemetry downlink, we report further analysis of BAT GRB 240805B (trigger #1246989) (Williams, et al., GCN Circ. 37043). The BAT ground-calculated position is RA, Dec = 254.215, 18.314 deg which is RA(J2000) = 16h 56m 51.5s Dec(J2000) = +18d 18' 49.9" with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 85%. The mask-weighted BAT light curve shows a complex structure with a duration of ~ 100 sec. T90 (15-350 keV) is 64.99 +- 2.56 sec (estimated error including systematics). The time-averaged spectrum from T-0.76 to T+96.68 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 1.07 +- 0.26, and Epeak of 72.1 +- 12.0 keV (chi squared 38.84 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 4.5 +- 0.2 x 10^-06 erg/cm2 and the 1-sec peak flux measured from T+15.95 sec in the 15-150 keV band is 2.4 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.71 +- 0.06 (chi squared 59.87 for 57 d.o.f.). All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at https://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1246989
GCN 37086 table
GRB_name GRB240805B
GCN_number 37086
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 37086 SUBJECT: GRB 240805B: GIT optical upper limit DATE: 24/08/06 22:49:44 GMT FROM: vishwajeet.s@iitb.ac.in T. Mohan, R. Kumar, Y. Wagh, V. Swain, V. Bhalerao (IITB), G.C. Anupama, S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team: We observed the field of GRB240805B (Williams et al., GCN 37043) with the 0.7m GROWTH-India Telescope (GIT). The observations started at 2024-08-06 17:26:53 UT, 1.12 days after the Swift BAT trigger. We obtained 10 images of 240s exposure time in r' filter. We did not detect any new source in our stacked image around the coordinates reported by Swift-XRT detection (Goad et al., GCN 37053) and BTA 6-meter telescope (Moskvitin et al., GCN 37055). The obtained upper limit follows as: -------------------------------------------------------------------------------------- | JD (mid) | t-t0 (days) | Filter | Exposure (s) | Limiting Magnitude (AB) | | ------------------ | ----------- |------- | ------------ | ----------------------- | | 2460529.2419108795 | 1.14 | r' | 10x240 | 22.5 | -------------------------------------------------------------------------------------- Our result is consistent with the upper limits reported by (Strausbaugh et al, GCN 37052; Maksut et al, GCN 37060; Pankov et al., GCN 37072; Quadri et al., GCN 37076). The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction. The GROWTH India Telescope (GIT, Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/.
GCN 37192 table
GRB_name GRB240805B
GCN_number 37192
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 37192 SUBJECT: GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit DATE: 24/08/16 19:36:14 GMT FROM: Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy - MPC Code C82 Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy in a large collaboration with: M.G. Dainotti (National Astronomical Observatory of Japan), Y. Niino (Tokyo University, Institute of Astronomy), K. Kalinowski (Aarhus University, Department of Physics and Astronomy), B. De Simone (Universita' degli Studi Di Salerno) report: We imaged the field of the GRB 240805B detected at 14:28:54 UT by SWIFT (trigger num. 1246989) (M. A. Williams (PSU), S. Dichiara (PSU), R. Gupta (NASA GSFC), J. A. Kennea (PSU) and D. M. Palmer (LANL) GCN 37043) with telescope of Nastro Verde Observatory - Sorrento (Naples), Italy. Member of: AAVSO - American Association of Variable Star Observers. UAI/SSV - Unione Astrofili Italiani/sezione stelle variabili. AstroCampania Associazione The observations started at 19:24 UT of 2024/08/05, after about 5 hours after the transient, with clear sky, with principal telescope SC 0.35 f/10 with focal reduced + CCD Sbig ST10 XME I took 45 image of 60 sec each. All images are unfiltered, calibrated with masterdark and masterflat,stacked with Tycho Tracker software We have not detected any clearly visible sources, up to 19.5th magnitude with clear skies. Start End Rlim 19:24:41 UT 20:27:39 UT 19.5 We did not found any optical counterpart. Magnitudes were estimated with the Gaia DR2 cat. and are not corrected for galactic dust extinction. The message may be cited.