TDRSS lightcurve for Trigger=968211

Notes:

GCN BAT Position Notice

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 27 Apr 20 18:26:35 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     968211,   Seg_Num: 0
GRB_RA:          293.735d {+19h 34m 56s} (J2000),
                 293.954d {+19h 35m 49s} (current),
                 293.197d {+19h 32m 47s} (1950)
GRB_DEC:         +21.895d {+21d 53' 43"} (J2000),
                 +21.941d {+21d 56' 28"} (current),
                 +21.785d {+21d 47' 04"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       1427 [cnts]    Image_Peak=357 [image_cnts]
TRIGGER_DUR:     0.032 [sec] 
TRIGGER_INDEX:   10309     E_range: 15-50 keV
BKG_INTEN:       17253 [cnts]
BKG_TIME:        66367.15 SOD {18:26:07.15} UT
BKG_DUR:         8 [sec]
GRB_DATE:        18966 TJD;   118 DOY;   20/04/27
GRB_TIME:        66379.95 SOD {18:26:19.95} UT
GRB_PHI:           1.52 [deg]
GRB_THETA:        28.22 [deg]
SOLN_STATUS:     0x2000010D
RATE_SIGNIF:     159.54 [sigma]
IMAGE_SIGNIF:    19.26 [sigma]
MERIT_PARAMS:     +0  +0  +2  -5  +1  +6  +0  +1  +9  +0 
SUN_POSTN:        35.58d {+02h 22m 20s}  +14.16d {+14d 09' 26"}
SUN_DIST:         95.16 [deg]   Sun_angle= 6.8 [hr] (West of Sun)
MOON_POSTN:       90.50d {+06h 01m 59s}  +23.49d {+23d 29' 25"}
MOON_DIST:       129.16 [deg]
MOON_ILLUM:      20 [%]
GAL_COORDS:       57.25,  0.82 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      300.62, 42.84 [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 matches a source in the on-board catalog: Num=10762=sgr1935p2154,   delta=0.004 [deg].  
COMMENTS:        This matches a source in the ground catalog: sgr1935p2154,   delta=0.004 [deg].  
COMMENTS:        This is not a GRB.  
COMMENTS:        This is an interesting source.  
COMMENTS:        This trigger occurred at longitude,latitude = 166.50,-20.33 [deg].  
COMMENTS:           

GCN BAT Lightcurve Notice

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 27 Apr 20 18:30:52 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     968211,   Seg_Num: 0
GRB_RA:          293.735d {+19h 34m 56s} (J2000),
                 293.954d {+19h 35m 49s} (current),
                 293.197d {+19h 32m 47s} (1950)
GRB_DEC:         +21.895d {+21d 53' 43"} (J2000),
                 +21.941d {+21d 56' 28"} (current),
                 +21.785d {+21d 47' 04"} (1950)
GRB_DATE:        18966 TJD;   118 DOY;   20/04/27
GRB_TIME:        66380.14 SOD {18:26:20.14} UT
TRIGGER_INDEX:   10309
GRB_PHI:           1.52 [deg]
GRB_THETA:        28.22 [deg]
DELTA_TIME:      -17.00 [sec]
TRIGGER_DUR:     0.032 [sec] 
SOLN_STATUS:     0x10D
RATE_SIGNIF:     159.54 [sigma]
IMAGE_SIGNIF:    19.26 [sigma]
LC_URL:          sw00968211000msb.lc

GCN template for BAT paragraph

  • Click here!
    At 18:26:20 UT, the Swift Burst Alert Telescope (BAT) triggered and
    located GRB 200427 ***A*** (trigger=968211).  Swift slewed immediately to the burst.
    The BAT on-board calculated location is 
    RA, Dec 293.735, +21.895 which is 
       RA(J2000) = 19h 34m 56s
       Dec(J2000) = +21d 53' 43"
    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 ~14601 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

    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: 23.936 s +/- 45.12 s
      Estimated T50 duration: 0.128 s +/- 0.128 s
      Estimated Peak Interval: MET   609704805.18400002 +/- 0.500000 s
      Estimated background rate 1:     3980.200 near MET 609704792.896000 s
      Estimated background rate 2:     3894.832 near MET 609704937.472000 s
      Estimated total duration: 79.232 s (for data selection)
           (from MET 609704804.992000 to MET 609704884.224000)
      Estimated total fluence: 2307.042263 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 293.735 21.895 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 293.735 21.895
    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: 2020 4 27 18 28.790946  62.537145
     Obj: 2020 4 27 18 122.475849  -3.922830
    
  • the object visibility at GSFC, Greenbelt, Maryland
     
    MMT Observatory, Mt. Hopkins, Arizona
          TimeUT       Azimuth     Elevation
     Sun: 2020 4 27 18 307.946333  64.139397
     Obj: 2020 4 27 18 104.713833  18.734801
    
  • the object visibility at MMT, Mt. Hopkins, Arizona
     
    Hale Telescope, Palomar Mountain, California
          TimeUT       Azimuth     Elevation
     Sun: 2020 4 27 18 301.906877  59.045311
     Obj: 2020 4 27 18 101.303782  24.026154
    
  • the object visibility at Hale Telescope, Palomar Mt., California
     
    Mauna Kea, Hawaii
          TimeUT       Azimuth     Elevation
     Sun: 2020 4 27 18 263.983286  27.576447
     Obj: 2020 4 27 18 100.097313  56.106867
    
  • the object visibility at Mauna Kea, Hawaii
     
    Siding Spring Obs., Australia
          TimeUT       Azimuth     Elevation
     Sun: 2020 4 27 18 273.360493  -33.501607
     Obj: 2020 4 27 18 201.503155  33.650067
    
  • the object visibility at Siding Spring Obs., Australia
     
    Tokyo, Japan
          TimeUT       Azimuth     Elevation
     Sun: 2020 4 27 18 227.297451  -26.838923
     Obj: 2020 4 27 18 282.133728  56.255753
    
  • the object visibility at Tokyo, Japan
     
    William Herschel Telescope, La Palma, Canary Islands, Spain
          TimeUT       Azimuth     Elevation
     Sun: 2020 4 27 18 94.467786  22.116951
     Obj: 2020 4 27 18 172.659451  -38.989277
    
  • the object visibility at William Hershel Telescope, La Palma, Canary Islands, Spain
     
    Gemini South, Cerro Pachon, Chile
          TimeUT       Azimuth     Elevation
     Sun: 2020 4 27 18 154.746981  41.813811
     Obj: 2020 4 27 18 95.939972  -36.760341
    
  • the object visibility at Gemini South, Cerro Pachon, Chile
     
     
     
    The data/results are in /local/data/bat1/prebascript/trigger968211/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:
    Mon Apr 27 14:32:23 EDT 2020