TDRSS lightcurve for Trigger=1351790

Notes:

GCN BAT Position Notice

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 24 Sep 25 08:19:41 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     1351790,   Seg_Num: 0
GRB_RA:           51.865d {+03h 27m 28s} (J2000),
                  52.608d {+03h 30m 26s} (current),
                  50.439d {+03h 21m 45s} (1950)
GRB_DEC:         +74.652d {+74d 39' 07"} (J2000),
                 +74.740d {+74d 44' 23"} (current),
                 +74.477d {+74d 28' 38"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       28074 [cnts]    Image_Peak=350 [image_cnts]
TRIGGER_DUR:     16.384 [sec] 
TRIGGER_INDEX:   492     E_range: 50-350 keV
BKG_INTEN:       98301 [cnts]
BKG_TIME:        29811.61 SOD {08:16:51.61} UT
BKG_DUR:         64 [sec]
GRB_DATE:        20942 TJD;   267 DOY;   25/09/24
GRB_TIME:        29909.27 SOD {08:18:29.27} UT
GRB_PHI:         -165.17 [deg]
GRB_THETA:        54.75 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     13.92 [sigma]
IMAGE_SIGNIF:    7.59 [sigma]
MERIT_PARAMS:     +1  +0  +0  +4  +3  -2  +0  +0 +17  +0 
SUN_POSTN:       181.42d {+12h 05m 40s}   -0.61d {-00d 36' 49"}
SUN_DIST:        100.10 [deg]   Sun_angle= 8.6 [hr] (West of Sun)
MOON_POSTN:      206.33d {+13h 45m 19s}  -14.67d {-14d 40' 00"}
MOON_DIST:       118.20 [deg]
MOON_ILLUM:      6 [%]
GAL_COORDS:      132.86, 14.87 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       74.12, 53.32 [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 = 278.86,3.66 [deg].  

GCN BAT Lightcurve Notice

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Wed 24 Sep 25 08:40:42 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     1351790,   Seg_Num: 0
GRB_RA:           51.865d {+03h 27m 28s} (J2000),
                  52.608d {+03h 30m 26s} (current),
                  50.439d {+03h 21m 45s} (1950)
GRB_DEC:         +74.652d {+74d 39' 07"} (J2000),
                 +74.740d {+74d 44' 23"} (current),
                 +74.477d {+74d 28' 38"} (1950)
GRB_DATE:        20942 TJD;   267 DOY;   25/09/24
GRB_TIME:        29909.27 SOD {08:18:29.27} UT
TRIGGER_INDEX:   492
GRB_PHI:         -165.17 [deg]
GRB_THETA:        54.75 [deg]
DELTA_TIME:      -5.00 [sec]
TRIGGER_DUR:     16.384 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     13.92 [sigma]
IMAGE_SIGNIF:    7.59 [sigma]
LC_URL:          sw01351790000msb.lc

GCN template for BAT paragraph

  • Click here!
    At 08:18:29 UT, the Swift Burst Alert Telescope (BAT) triggered and
    located GRB 250924 ***A*** (trigger=1351790).  Swift slewed immediately to the burst.
    The BAT on-board calculated location is 
    RA, Dec 51.865, +74.652 which is 
       RA(J2000) = 03h 27m 28s
       Dec(J2000) = +74d 39' 07"
    with an uncertainty of 3 arcmin (radius, 90% containment, including 
    systematic uncertainty).  The BAT light curve showed a [**double-peaked**]
    structure with a duration of about TTT sec.  The peak count rate
    was ~1106 counts/sec (15-350 keV), at ~17 sec after the trigger.
    
  • Test version of draft template

    Initial TDRSS lightcurve and spacecraft attitude plot

    TDRSS lightcurve from T0-30 to T0+50 (zoom in)

    TDRSS light curve from T0-1 to T0+2 (More zoom in)

    1.6s binned TDRSS light curve

    Tilan's background subtracted TDRSS light curves

    Extended TDRSS light curve and spacecraft attitude plot(s)

    Extended TDRSS lc No.1

    Extended TDRSS lc No.2

    Extended TDRSS lc No.3

    Extended TDRSS lc No.4

    TDRSS extended lightcurve from T0-1 to T0+2

    T50 and T90 calculation

    ******************************************
             battblocks v1.18
    ------------------------------------------
         Input Data: bat_raw_lc.fits
         Output GTI: bb.gti
     Events to Skip: 128     Changepoint log(prob) Prior: 6.000000
      Internal Tick: 1.000000e-04 s
      Lookback time: 0 s
     Bkg. Subtract?: yes (for fluence/T50/T90 calculations)
    ------------------------------------------
      Estimated T90 duration: 140.608 s +/- 2.90513 s
      Estimated T50 duration: 98.048 s +/- 4.16738 s
      Estimated Peak Interval: MET   780394859.83999991 +/- 0.500000 s
      Estimated background rate 1:     3846.875 near MET 780394728.800000 s
      Estimated background rate 2:     3665.991 near MET 780394911.040000 s
      Estimated total duration: 154.56 s (for data selection)
           (from MET 780394736.000000 to MET 780394890.560000)
      Estimated total fluence: 21260.221568 count
      Created GTI with 5 entries
    ------------------------------------------
     
    

    Search for this GRB position to the previously BAT detected GRB positions (search radius within 5 arcmin)

    bat_grb_pos_cat.sh 51.865 74.652 0.083
    No match
    

    Search for this GRB position to the source locations in BAT transient monitor (search radius within 12 arcmin)

    python compare_catalog.py 51.865 74.652
    No match
    

    Link to SIMBAD

  • Click here for the SIMBAD search!

    Frank's UVOT result

  • Click here!

    Frank's UVOT Blinking images

  • Click here!

    Elevation angle of GRB/Sun at the ground telescope locations

    GSFC, Greenbelt, Maryland
          TimeUT       Azimuth     Elevation
     Sun: 2025 9 24 8 237.959900  -34.070099
     Obj: 2025 9 24 8 182.948295  54.110415
    
  • the object visibility at GSFC, Greenbelt, Maryland
     
    MMT Observatory, Mt. Hopkins, Arizona
          TimeUT       Azimuth     Elevation
     Sun: 2025 9 24 8 199.978639  -57.361666
     Obj: 2025 9 24 8 193.448608  42.572341
    
  • the object visibility at MMT, Mt. Hopkins, Arizona
     
    Hale Telescope, Palomar Mountain, California
          TimeUT       Azimuth     Elevation
     Sun: 2025 9 24 8 188.537486  -56.989382
     Obj: 2025 9 24 8 195.139304  42.941042
    
  • the object visibility at Hale Telescope, Palomar Mt., California
     
    Mauna Kea, Hawaii
          TimeUT       Azimuth     Elevation
     Sun: 2025 9 24 8 115.914027  -51.633707
     Obj: 2025 9 24 8 196.247019  20.346273
    
  • the object visibility at Mauna Kea, Hawaii
     
    Siding Spring Obs., Australia
          TimeUT       Azimuth     Elevation
     Sun: 2025 9 24 8 89.178568  -0.210387
     Obj: 2025 9 24 8 193.077906  -42.471469
    
  • the object visibility at Siding Spring Obs., Australia
     
    Tokyo, Japan
          TimeUT       Azimuth     Elevation
     Sun: 2025 9 24 8 80.261595  12.788185
     Obj: 2025 9 24 8 186.227323  20.137291
    
  • the object visibility at Tokyo, Japan
     
    William Herschel Telescope, La Palma, Canary Islands, Spain
          TimeUT       Azimuth     Elevation
     Sun: 2025 9 24 8 277.194316  11.581753
     Obj: 2025 9 24 8 164.814930  37.184113
    
  • the object visibility at William Hershel Telescope, La Palma, Canary Islands, Spain
     
    Gemini South, Cerro Pachon, Chile
          TimeUT       Azimuth     Elevation
     Sun: 2025 9 24 8 293.166810  -32.937050
     Obj: 2025 9 24 8 180.183936  -15.112141
    
  • the object visibility at Gemini South, Cerro Pachon, Chile
     
     
     
    The data/results are in /local/data/bat1/prebascript/trigger1351790/tdrss_ql/
     
    bat_raw_lc.fits  : TDRSS FITS light curve from GCN
    gcn_position.txt : GCN BAT position notice
    ratelc_tdrss.qdp : QDP file of the TDRSS light curve
    tdrss_lc.gif     : GIF TDRSS light curve
    sc_att.qdp       : QDP file of the spacecraft attitude
    sc_att.gif       : GIF spacecraft attitude
    bb.gti           : Bayesian block GTI file (battblocks)
    dur.gti          : Duration GTI file (battblocks)
    battblocks.log   : Output log of battblocks
     
    
    
    Plot creation:
    Wed Sep 24 04:41:43 EDT 2025