TDRSS lightcurve for Trigger=829046

Notes:

GCN BAT Position Notice

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 26 Apr 18 13:20:12 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     829046,   Seg_Num: 0
GRB_RA:           57.459d {+03h 49m 50s} (J2000),
                  57.595d {+03h 50m 23s} (current),
                  57.086d {+03h 48m 21s} (1950)
GRB_DEC:         -48.782d {-48d 46' 53"} (J2000),
                 -48.727d {-48d 43' 36"} (current),
                 -48.932d {-48d 55' 55"} (1950)
GRB_ERROR:       4.00 [arcmin radius, statistical only]
GRB_INTEN:       0 [cnts]    Image_Peak=1003 [image_cnts]
TRIGGER_DUR:     64.000 [sec] 
TRIGGER_INDEX:   20000     E_range: 15-50 keV
BKG_INTEN:       0 [cnts]
BKG_TIME:        0.00 SOD {00:00:00.00} UT
BKG_DUR:         0 [sec]
GRB_DATE:        18234 TJD;   116 DOY;   18/04/26
GRB_TIME:        47915.15 SOD {13:18:35.15} UT
GRB_PHI:         149.08 [deg]
GRB_THETA:        16.70 [deg]
SOLN_STATUS:     0x1099D
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    5.86 [sigma]
MERIT_PARAMS:     +0  +0 +125  +6  +1  -5  +0  +0 -40  +1 
SUN_POSTN:        33.95d {+02h 15m 47s}  +13.61d {+13d 36' 29"}
SUN_DIST:         65.77 [deg]   Sun_angle= -1.6 [hr] (East of Sun)
MOON_POSTN:      175.16d {+11h 40m 38s}   +5.84d {+05d 50' 20"}
MOON_DIST:       112.34 [deg]
MOON_ILLUM:      87 [%]
GAL_COORDS:      257.49,-49.51 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       30.70,-65.66 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is an image trigger.  (The RATE_SIGNIF & BKG_{INTEN, TIME, DUR} are undefined.)  
COMMENTS:        A point_source was found.  
COMMENTS:        This is a low-flux event whose position matches one of the nearby galaxy sources in the on-board catalog!  
COMMENTS:        This matches a source in the on-board catalog: Num=12251=I2000,   delta=0.139 [deg].  
COMMENTS:        This matches a source in the ground catalog: I2000,   delta=0.139 [deg].  
COMMENTS:        This is a GRB in nearby galaxy or it is noise.  
COMMENTS:        This trigger occurred at longitude,latitude = 12.44,-13.68 [deg].  

GCN BAT Lightcurve Notice

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 26 Apr 18 13:35:43 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     829046,   Seg_Num: 0
GRB_RA:           57.459d {+03h 49m 50s} (J2000),
                  57.595d {+03h 50m 23s} (current),
                  57.086d {+03h 48m 21s} (1950)
GRB_DEC:         -48.782d {-48d 46' 53"} (J2000),
                 -48.727d {-48d 43' 36"} (current),
                 -48.932d {-48d 55' 55"} (1950)
GRB_DATE:        18234 TJD;   116 DOY;   18/04/26
GRB_TIME:        47915.15 SOD {13:18:35.15} UT
TRIGGER_INDEX:   20000
GRB_PHI:         149.08 [deg]
GRB_THETA:        16.70 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     64.000 [sec] 
SOLN_STATUS:     0x99D
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    5.86 [sigma]
LC_URL:          sw00829046000msb.lc

GCN template for BAT paragraph

  • Click here!
    At 13:18:35 UT, the Swift Burst Alert Telescope (BAT) triggered and
    located GRB 180426 ***A*** (trigger=829046).  Swift slewed immediately to the burst.
    The BAT on-board calculated location is 
    RA, Dec 57.459, -48.782 which is 
       RA(J2000) = 03h 49m 50s
       Dec(J2000) = -48d 46' 53"
    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 ~1351 counts/sec (15-350 keV), at ~2 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: 73.728 s +/- 73.8417 s
      Estimated T50 duration: 73.728 s +/- 73.8417 s
      Estimated Peak Interval: MET   546441662.52800000 +/- 0.500000 s
      Estimated background rate 1:     6167.409 near MET 546441557.568000 s
      Estimated background rate 2:     6111.994 near MET 546441699.392000 s
      Estimated total duration: 73.728 s (for data selection)
           (from MET 546441603.136000 to MET 546441676.864000)
      Estimated total fluence: -3024.553774 count
      Created GTI with 4 entries
    ------------------------------------------
     
    

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

    bat_grb_pos_cat.sh 57.459 -48.782 0.083
    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: 2018 4 26 13 277.044414  30.276853
     Obj: 2018 4 26 13 313.161928  -25.672189
    
  • the object visibility at GSFC, Greenbelt, Maryland
     
    MMT Observatory, Mt. Hopkins, Arizona
          TimeUT       Azimuth     Elevation
     Sun: 2018 4 26 13 255.385000  2.232003
     Obj: 2018 4 26 13 309.241119  -42.178776
    
  • the object visibility at MMT, Mt. Hopkins, Arizona
     
    Hale Telescope, Palomar Mountain, California
          TimeUT       Azimuth     Elevation
     Sun: 2018 4 26 13 252.170095  -2.147746
     Obj: 2018 4 26 13 307.841700  -47.160836
    
  • the object visibility at Hale Telescope, Palomar Mt., California
     
    Mauna Kea, Hawaii
          TimeUT       Azimuth     Elevation
     Sun: 2018 4 26 13 232.482019  -38.691796
     Obj: 2018 4 26 13 339.791111  -58.417662
    
  • the object visibility at Mauna Kea, Hawaii
     
    Siding Spring Obs., Australia
          TimeUT       Azimuth     Elevation
     Sun: 2018 4 26 13 43.086402  -67.100177
     Obj: 2018 4 26 13 24.856786  -2.582846
    
  • the object visibility at Siding Spring Obs., Australia
     
    Tokyo, Japan
          TimeUT       Azimuth     Elevation
     Sun: 2018 4 26 13 141.535892  -32.944004
     Obj: 2018 4 26 13 53.020709  -46.724462
    
  • the object visibility at Tokyo, Japan
     
    William Herschel Telescope, La Palma, Canary Islands, Spain
          TimeUT       Azimuth     Elevation
     Sun: 2018 4 26 13 349.562151  74.622218
     Obj: 2018 4 26 13 342.670045  8.942511
    
  • the object visibility at William Hershel Telescope, La Palma, Canary Islands, Spain
     
    Gemini South, Cerro Pachon, Chile
          TimeUT       Azimuth     Elevation
     Sun: 2018 4 26 13 239.296774  20.516753
     Obj: 2018 4 26 13 312.208883  28.815365
    
  • the object visibility at Gemini South, Cerro Pachon, Chile
     
     
     
    The data/results are in /local/data/bat1/prebascript/trigger829046/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:
    Thu Apr 26 09:36:02 EDT 2018