TDRSS lightcurve for Trigger=1442454

Notes:

GCN BAT Position Notice

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Jan 26 18:00:53 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     1442454,   Seg_Num: 0
GRB_RA:          284.666d {+18h 58m 40s} (J2000),
                 284.736d {+18h 58m 57s} (current),
                 284.529d {+18h 58m 07s} (1950)
GRB_DEC:         +61.912d {+61d 54' 42"} (J2000),
                 +61.949d {+61d 56' 55"} (current),
                 +61.842d {+61d 50' 30"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       4625 [cnts]    Image_Peak=115 [image_cnts]
TRIGGER_DUR:     2.048 [sec] 
TRIGGER_INDEX:   271     E_range: 50-350 keV
BKG_INTEN:       32136 [cnts]
BKG_TIME:        64794.92 SOD {17:59:54.92} UT
BKG_DUR:         24 [sec]
GRB_DATE:        21060 TJD;    20 DOY;   26/01/20
GRB_TIME:        64826.15 SOD {18:00:26.15} UT
GRB_PHI:         -177.92 [deg]
GRB_THETA:        55.78 [deg]
SOLN_STATUS:     0x20000003
RATE_SIGNIF:     32.61 [sigma]
IMAGE_SIGNIF:    7.73 [sigma]
MERIT_PARAMS:     +1  +0  +0  +1  +3  -2  +0  +0 -11  +0 
SUN_POSTN:       302.90d {+20h 11m 36s}  -20.00d {-19d 59' 56"}
SUN_DIST:         83.22 [deg]   Sun_angle= 1.2 [hr] (West of Sun)
MOON_POSTN:      325.99d {+21h 43m 58s}  -15.25d {-15d 15' 02"}
MOON_DIST:        83.75 [deg]
MOON_ILLUM:      4 [%]
GAL_COORDS:       92.21, 22.90 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      330.67, 82.14 [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 = 216.75,6.15 [deg].  
COMMENTS:           
COMMENTS:        NOTE: This BAT event is temporally(0.0<100sec) coincident with the FERMI_GBM event (trignum=790624831).

GCN BAT Lightcurve Notice

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 20 Jan 26 18:24:27 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     1442454,   Seg_Num: 0
GRB_RA:          284.666d {+18h 58m 40s} (J2000),
                 284.736d {+18h 58m 57s} (current),
                 284.529d {+18h 58m 07s} (1950)
GRB_DEC:         +61.912d {+61d 54' 42"} (J2000),
                 +61.949d {+61d 56' 55"} (current),
                 +61.842d {+61d 50' 30"} (1950)
GRB_DATE:        21060 TJD;    20 DOY;   26/01/20
GRB_TIME:        64826.15 SOD {18:00:26.15} UT
TRIGGER_INDEX:   271
GRB_PHI:         -177.92 [deg]
GRB_THETA:        55.78 [deg]
DELTA_TIME:      77.00 [sec]
TRIGGER_DUR:     2.048 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     32.61 [sigma]
IMAGE_SIGNIF:    7.73 [sigma]
LC_URL:          sw01442454000msb.lc

GCN template for BAT paragraph

  • Click here! 
    At 18:00:26 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 260120 ***A*** (trigger=1442454).  Swift slewed immediately to the burst.
The BAT on-board calculated location is 
RA, Dec 284.666, +61.912 which is 
   RA(J2000) = 18h 58m 40s
   Dec(J2000) = +61d 54' 42"
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 ~2140 counts/sec (15-350 keV), at ~0 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: 22.784 s +/- 1.98812 s
  Estimated T50 duration: 4.992 s +/- 0.64 s
  Estimated Peak Interval: MET   790624864.25600004 +/- 0.500000 s
  Estimated background rate 1:     3758.214 near MET 790624851.200000 s
  Estimated background rate 2:     3522.351 near MET 790624990.528000 s
  Estimated total duration: 68.736 s (for data selection)
       (from MET 790624862.400000 to MET 790624931.136000)
  Estimated total fluence: 6355.521963 count
  Created GTI with 7 entries
------------------------------------------

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

    bat_grb_pos_cat.sh 284.666 61.912 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 284.666 61.912
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: 2026 1 20 18 10.721792  30.242590
 Obj: 2026 1 20 18 152.512990  61.391471
  • the object visibility at GSFC, Greenbelt, Maryland 
     
MMT Observatory, Mt. Hopkins, Arizona
      TimeUT       Azimuth     Elevation
 Sun: 2026 1 20 18 332.590232  33.327436
 Obj: 2026 1 20 18 185.543251  59.471833
  • the object visibility at MMT, Mt. Hopkins, Arizona 
     
Hale Telescope, Palomar Mountain, California
      TimeUT       Azimuth     Elevation
 Sun: 2026 1 20 18 327.217360  29.353907
 Obj: 2026 1 20 18 191.386916  60.380059
  • the object visibility at Hale Telescope, Palomar Mt., California 
     
Mauna Kea, Hawaii
      TimeUT       Azimuth     Elevation
 Sun: 2026 1 20 18 296.544331  11.760966
 Obj: 2026 1 20 18 206.490565  35.450453
  • the object visibility at Mauna Kea, Hawaii 
     
Siding Spring Obs., Australia
      TimeUT       Azimuth     Elevation
 Sun: 2026 1 20 18 306.100167  -15.922260
 Obj: 2026 1 20 18 213.350281  -34.733101
  • the object visibility at Siding Spring Obs., Australia 
     
Tokyo, Japan
      TimeUT       Azimuth     Elevation
 Sun: 2026 1 20 18 257.714407  -52.611149
 Obj: 2026 1 20 18 204.432782  16.780731
  • the object visibility at Tokyo, Japan 
     
William Herschel Telescope, La Palma, Canary Islands, Spain
      TimeUT       Azimuth     Elevation
 Sun: 2026 1 20 18 62.147291  7.590879
 Obj: 2026 1 20 18 148.352100  26.454654
  • the object visibility at William Hershel Telescope, La Palma, Canary Islands, Spain 
     
Gemini South, Cerro Pachon, Chile
      TimeUT       Azimuth     Elevation
 Sun: 2026 1 20 18 122.349778  72.421495
 Obj: 2026 1 20 18 164.695349  -6.289322
  • the object visibility at Gemini South, Cerro Pachon, Chile 
     
 
 
The data/results are in /local/data/bat1/prebascript/trigger1442454/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:
Tue Jan 20 13:24:43 EST 2026