Gamma-ray Burst 240829A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN/BACODINE POSITION NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Thu 29 Aug 24 03:56:48 UT
  NOTICE_TYPE:     Swift-BAT GRB Position
  TRIGGER_NUM:     1251252,   Seg_Num: 0
  GRB_RA:          143.059d {+09h 32m 14s} (J2000),
                   143.347d {+09h 33m 23s} (current),
                   142.475d {+09h 29m 54s} (1950)
  GRB_DEC:         -18.728d {-18d 43' 40"} (J2000),
                   -18.838d {-18d 50' 16"} (current),
                   -18.506d {-18d 30' 22"} (1950)
  GRB_ERROR:       3.00 [arcmin radius, statistical only]
  GRB_INTEN:       2933 [cnts]    Image_Peak=113 [image_cnts]
  TRIGGER_DUR:     1.024 [sec] 
  TRIGGER_INDEX:   148     E_range: 25-100 keV
  BKG_INTEN:       17380 [cnts]
  BKG_TIME:        14173.92 SOD {03:56:13.92} UT
  BKG_DUR:         8 [sec]
  GRB_DATE:        20551 TJD;   242 DOY;   24/08/29
  GRB_TIME:        14188.45 SOD {03:56:28.45} UT
  GRB_PHI:         -67.32 [deg]
  GRB_THETA:        39.29 [deg]
  SOLN_STATUS:     0x3
  RATE_SIGNIF:     15.68 [sigma]
  IMAGE_SIGNIF:    8.00 [sigma]
  MERIT_PARAMS:     +1  +0  +0  +0  +2  -2 -100  +0 -85  +0 
  SUN_POSTN:       158.08d {+10h 32m 18s}   +9.19d {+09d 11' 36"}
  SUN_DIST:         31.57 [deg]   Sun_angle= 1.0 [hr] (West of Sun)
  MOON_POSTN:      101.73d {+06h 46m 55s}  +28.27d {+28d 16' 24"}
  MOON_DIST:        61.95 [deg]
  MOON_ILLUM:      22 [%]
  GAL_COORDS:      250.90, 23.43 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      152.47,-31.40 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Coordinates.  
  COMMENTS:        This is a rate trigger.  
  COMMENTS:        A point_source was found.  
  COMMENTS:        This does not match any source in the on-board catalog.  
  COMMENTS:        This does not match any source in the ground catalog.  
  COMMENTS:        This is a GRB.  
  COMMENTS:        This trigger occurred at longitude,latitude = 76.60,20.49 [deg].  
  

• red DSS finding chart ps-file
  
  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Thu 29 Aug 24 04:00:21 UT
  NOTICE_TYPE:     Swift-BAT GRB Lightcurve
  TRIGGER_NUM:     1251252,   Seg_Num: 0
  GRB_RA:          143.059d {+09h 32m 14s} (J2000),
                   143.347d {+09h 33m 23s} (current),
                   142.475d {+09h 29m 54s} (1950)
  GRB_DEC:         -18.728d {-18d 43' 40"} (J2000),
                   -18.838d {-18d 50' 16"} (current),
                   -18.506d {-18d 30' 22"} (1950)
  GRB_DATE:        20551 TJD;   242 DOY;   24/08/29
  GRB_TIME:        14188.45 SOD {03:56:28.45} UT
  TRIGGER_INDEX:   148
  GRB_PHI:         -67.32 [deg]
  GRB_THETA:        39.29 [deg]
  DELTA_TIME:      -11.00 [sec]
  TRIGGER_DUR:     1.024 [sec] 
  SOLN_STATUS:     0x3
  RATE_SIGNIF:     15.68 [sigma]
  IMAGE_SIGNIF:    8.00 [sigma]
  LC_URL:          sw01251252000msb.lc
  SUN_POSTN:       158.08d {+10h 32m 19s}   +9.19d {+09d 11' 32"}
  SUN_DIST:         31.57 [deg]   Sun_angle= 1.0 [hr] (West of Sun)
  MOON_POSTN:      101.76d {+06h 47m 04s}  +28.27d {+28d 16' 14"}
  MOON_DIST:        61.93 [deg]
  MOON_ILLUM:      22 [%]
  GAL_COORDS:      250.90, 23.43 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      152.47,-31.40 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Lightcurve.  
  COMMENTS:           
  COMMENTS:        The next comments were copied from the BAT_POS Notice:  
  COMMENTS:        This is a rate trigger.  
  COMMENTS:        A point_source was found.  
  COMMENTS:        This does not match any source in the on-board catalog.  
  COMMENTS:        This does not match any source in the ground catalog.  
  COMMENTS:        This is a GRB.  
  COMMENTS:        This trigger occurred at longitude,latitude = 76.60,20.49 [deg].  
  

  
• GCN Circular #37332
  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-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB240829.16 (trigger No 1251252,09h 32m 14.16s , -18d 43m 40.8s, R=0.05) errorbox 24 sec after notice time and 46 sec after trigger time at 2024-08-29 03:57:14 UT, with upper limit up to 15.6 mag. Observations started at twilight. The observations began at zenith distance = 76 deg. The sun altitude is -13.9 deg.
  The galactic latitude b = 24 deg., longitude l = 251 deg.
  Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2580148
  We obtain a following upper limits.

  Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
  _________|_____________________|_____|_______|______|________
  
        52 |         MASTER-SAAO |  P/ |    10 | 15.4 |        
        69 |         MASTER-SAAO |  P/ |    10 | 15.6 |        
  

  The observation and reduction will continue. The message may be cited.
• GCN Circular #37333
  S. Laha (GSFC/UMBC), K. L. Page (U Leicester), D. M. Palmer (LANL) and A. Tohuvavohu (U Toronto) report on behalf of the Neil Gehrels Swift Observatory Team:
  At 03:56:28 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 240829A (trigger=1251252). Swift did not slew to the burst due to an observing constraint. The BAT on-board calculated location is RA, Dec 143.059, -18.728 which is

     RA(J2000) = 09h 32m 14s
     Dec(J2000) = -18d 43' 40"
  

  with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex peak structure with a duration of about 40 sec. The peak count rate was ~1500 counts/sec (15-350 keV), at ~1 sec after the trigger.
  Due to a Sun observing constraint, Swift cannot slew to the BAT position until 12:04 UT on 2024 October 02. There will thus be no XRT or UVOT data for this trigger before this time.
  Burst Advocate for this burst is S. Laha (sib.laha AT gmail.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/)
• GCN Circular #37356
  D. M. Palmer (LANL), S. D. Barthelmy (GSFC), R. Gupta (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), M. J. Moss (GSFC), T. Parsotan (GSFC), D. Sadaula (GSFC/UMBC), T. Sakamoto (AGU) (i.e. the Swift-BAT team):
  Using the data set from T-61 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 240829A (trigger #1251252) (Laha, et al., GCN Circ. 37333). The BAT ground-calculated position is RA, Dec = 143.079, -18.687 deg which is

     RA(J2000)  =  09h 32m 18.9s
     Dec(J2000) = -18d 41' 13.0"
  

  with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 15%.
  The mask-weighted light curve displays a combination of two to three dim fast- rise-exponential-decay pulses. The T90 (15-350 keV) is 43.20 +- 10.47 sec (estimated error including systematics).
  The time-averaged spectrum from T-12.53 to T+51.47 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.66 +- 0.11. The fluence in the 15-150 keV band is 3.8 +- 0.3 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+10.97 sec in the 15-150 keV band is 0.0 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
  Swift did not slew to the BAT position due to the burst being sun constrained.
  The results of the batgrbproduct analysis are available at https://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1251252