Analysis for Ground-detected GRB: Trigger=376211

Analysis Summary

Notes:

==========================================================================
           BAT GROUND-DETECTED GRB DATA PROCESSING REPORT                 
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Sun May 10 02:16:33 EDT 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/ground_detect_bursts/scripts
======================================================================

  Trigger: 00376211      Segment: 000

  BAT Trigger Time: 280172670.72
               UTC: 2009-11-17T17:44:25.451   [includes UTCF correction]
       Where From?: Ground analysis (best_duration.txt)
  NOTE: BAT trigger time for ground-detected burst is the T100 start time.
 
  Refined Position:   [ source = BAT pre-slew image ]
    RA: 30.9584269946   Dec: -16.9458794914  [deg; J2000]
        { 02h 03m 50.0s , -16d -56' -45.2" }
        +/- 2.78625836544 [arcmin] (estimated 90% radius based on SNR)
    SNR: 7.03769370257
 
  Angular difference between the GCN position (ra=30.966, dec=-16.943 deg) and this refined position is 0.468 arcmin
 
  Partial Coding Fraction: 0.07910156    [ including projection effects ]

  Duration (found by FRED-model fit)
     T90: 0.64 +/- N/A
        Measured from: 0.064
                   to: 0.704     [s; relative to TRIGTIME]
     T50: 0.192 +/- N/A
        Measured from: 0.192
                   to: 0.384
 
=== Fluence/Peak Flux Summary ===
 
              Model    Band1    Band2    Band3    Band4    Band5    Total      
                       15-25    25-50   50-100  100-350   15-150   15-350   keV
Fluence   Power-law 1.07e-08 3.44e-08 9.13e-08 7.08e-07 2.49e-07 8.44e-07   erg/cm2
              Error 6.89e-09 1.32e-08 2.11e-08 4.43e-07 5.91e-08 4.41e-07   erg/cm2
Peak flux Power-law 4.73e-01 7.11e-01 7.98e-01 1.70e+00 2.49e+00 3.68e+00   ph/cm2/s
              Error 2.49e-01 2.28e-01 1.82e-01 8.98e-01 5.87e-01 9.33e-01   ph/cm2/s
 
Fluence   Cutoff-PL 1.05e-08 3.42e-08 9.14e-08 7.13e-07 2.50e-07 8.49e-07   erg/cm2
              Error 5.69e-09 1.32e-08 1.64e-08 6.72e-07 5.88e-08 4.36e-07   erg/cm2
Peak flux Cutoff-PL 4.86e-01 7.20e-01 7.96e-01 1.65e+00 2.50e+00 3.66e+00   ph/cm2/s
              Error 2.55e-01 2.28e-01 1.94e-01 1.37e+00 5.87e-01 2.32e+00   ph/cm2/s
 
Fluence        Band -------- -------- -------- -------- -------- --------   erg/cm2
              Error -------- -------- -------- -------- -------- --------   erg/cm2
Peak flux      Band -------- -------- -------- -------- -------- --------   ph/cm2/s
              Error -------- -------- -------- -------- -------- --------   ph/cm2/s
 
=== Time-averaged spectral analysis ===
 
Model Ph_index Ph_90err Epeak  Epeak_90err Norm     Nomr_90err chi2   dof
PL    0.593    0.500    -      -           2.02e-02 5.90e-03   55.710 57
CPL   0.598    0.867    9999.4    0.0      2.05e-02 1.72e-02   55.740 56
 
 
=== 1-s peak spectral analysis ===
 
Model Ph_index Ph_90err Epeak  Epeak_90err Norm     Nomr_90err chi2   dof
PL    0.833    0.427    -      -           2.17e-02 5.23e-03   58.770 57
CPL   0.800    0.848    9987.0    0.0      2.26e-02 2.49e-02   58.870 56
 
Model      : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index   : photon index: E^-{Ph_index} (minus sign is not included in the index)
Ph_90err   : 90% error of the photon index
Epeak      : Epeak in keV
Epeak_90err: 90% error of Epeak
Norm       : normalization at 50 keV in PL model and at 1 keV in CPL model
Nomr_90err : 90% error of the normalization
chi2       : Chi-Squared
dof        : degree of freedom
 
=== Table of the duration information ==
 
        Value   tstart    tstop
T100    0.960    0.000    0.960
T90     0.640    0.064    0.704
T50     0.192    0.192    0.384
Peak    1.000   -0.244    0.756
  • Click here for the BAT GCN circular template
  • Special notes of this burst

    Image

    15.0-350.0 keV image (Event data)

    #RAcent DECcent POSerr Theta  Phi  Peak_Cts  SNR Name
    30.958 -16.946 0.027 44.822 45.812 0.322 7.038 TRIG_00376211
     
    Image time interval: 0.000 to 0.960 [sec]
    

    Lightcurves

    Notes:

    Best duration plot

    1 s binning

    From T0-310 s to T0+310 s
    From T100_start - 20 s to T100_end + 30 s
    Full time interval

    64 ms binning

    Full time interval
    From T100_start to T100_end
    From T0-5 sec to T0+5 sec

    16 ms binning

    From T100_start-5 s to T100_start+5 s

    8 ms binning

    From T100_start-3 s to T100_start+3 s

    2 ms binning

    From T100_start-1 s to T100_start+1 s

    SN=5 or 10 sec. binning (whichever binning is satisfied first)

    SN=5 or 10 sec. binning (T < 200 sec)

    Quad-rate summed light curves (from T0-300s to T0+1000s)

    Spectral Evolution

    Spectra

    Notes:

    Time averaged spectrum fit using the pre-slew DRM

    Power-law model
    Time interval is from    0.000 sec. to    0.960 sec.
     
    Spectral model in power-law:
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 0.592714     ( -0.544973   0.454056 )
    Norm@50keV  : 2.02170E-02    ( -0.00621943   0.00558269 )
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          55.71 using 59 PHA bins.
    # Reduced chi-squared =         0.9774 for     57 degrees of freedom 
    # Null hypothesis probability =   5.234674e-01
     
    Photon flux (15-150 keV)    in 0.96 sec: 2.36254 ( -0.60184  0.605409 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 2.49063e-07 ( -5.91625e-08  5.90842e-08 ) ergs/cm2
     
    
    Cutoff power-law model
    Time interval is from    0.000 sec. to    0.960 sec.
    Spectral model in the cutoff power-law:
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 0.598043     ( -0.829426   0.903775 )
    Epeak [keV] : 9999.35      ( -9999.36 -9999.36 )
    Norm@50keV  : 2.04875E-02    ( -0.00580796   0.0285543 )
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          55.74 using 59 PHA bins.
    # Reduced chi-squared =         0.9953 for     56 degrees of freedom 
    # Null hypothesis probability =   4.848219e-01
     
    Photon flux (15-150 keV)    in 0.96 sec: 2.38011 ( -0.61576  0.58834 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 2.49502e-07 ( -5.95411e-08  5.80963e-08 ) ergs/cm2
     
    
    Band function
    Time interval is from    0.000 sec. to    0.960 sec.
     
    Spectral model in the Band function:
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    alpha       : -0.787338   ( 0.787338   0.787338 )
    beta        : -0.592689    ( -0.453622   0.545093 )
    Epeak [keV] : 16.9701      ( -16.9701 -16.9701 )
    Norm@50keV   : 2.87179E-02    ( -0.0140812   236477 )
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          55.71 using 59 PHA bins.
    # Reduced chi-squared =          1.013 for     55 degrees of freedom 
    # Null hypothesis probability =   4.477958e-01
     
    Photon flux (15-150 keV)    in 0.96 sec:  (    ) ph/cm2/s
    Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
     
    
    Single BB
     
    Spectral model blackbody:
    ------------------------------------------------------------
    Parameters  : value    Lower 90%  Upper 90%
    kT [keV]    : 36.9741  (-12.1604  37.4035)
    R^2/D10^2   : 2.07775E-02  (-0.0207302   0.0430526)
    (R is the radius in km and D10 is the distance to the source in units of 10 kpc)
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          60.17 using 59 PHA bins.
    # Reduced chi-squared =          1.056 for     57 degrees of freedom 
    # Null hypothesis probability =   3.618275e-01
     
    Energy  Fluence     90% Error
    [keV]   [erg/cm2]   [erg/cm2]
    15- 25  3.719e-09   2.226e-09
    25- 50  2.476e-08   1.511e-08
    50-150  2.140e-07   1.273e-07
    15-150  2.425e-07   1.325e-07
    
    Thermal bremsstrahlung (OTTB)
     
     
    Spectral model: thermal bremsstrahlung
    ------------------------------------------------------------
    Parameters  : value         Lower 90%    Upper 90%
    kT [keV]    : 200.000       (      )
    Norm        : 9.45602       (-2.5012     2.50106)
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          68.14 using 59 PHA bins.
    # Reduced chi-squared =          1.195 for     57 degrees of freedom 
    # Null hypothesis probability =   1.482722e-01
     
    Energy  Fluence     90% Error
    [keV]   [erg/cm2]   [erg/cm2]
    15- 25  2.260e-08   1.375e-08
    25- 50  4.348e-08   2.658e-08
    50-150  9.535e-08   5.693e-08
    15-150  1.614e-07   9.734e-08
    
    Double BB
     
     
    Spectral model: bbodyrad<1> + bbodyrad<2>
    ------------------------------------------------------------
    Parameters  : value         Lower 90%    Upper 90%
    kT1 [keV]   : 9.00307        (-3.28224      3.61143)
    R1^2/D10^2  : 0.914743        (-0.813953      7.69173)
    kT2 [keV]   : 176.791        (-176.599      -176.599)
    R2^2/D10^2  : 8.53671E-04    (-0.000351795   0.019999)
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          53.98 using 59 PHA bins.
    # Reduced chi-squared =         0.9814 for     55 degrees of freedom 
    # Null hypothesis probability =   5.137585e-01
     
    Energy  Fluence     90% Error
    [keV]   [erg/cm2]   [erg/cm2]
    15- 25  1.478e-08   8.866e-09
    25- 50  3.728e-08   2.035e-08
    50-150  1.961e-07   5.434e-08
    15-150  2.482e-07   6.994e-08
    

    Peak spectrum fit

    Power-law model
    Time interval is from   -0.244 sec. to    0.756 sec.
     
    Spectral model in power-law:
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 0.832574     ( -0.451085   0.403544 )
    Norm@50keV  : 2.17172E-02    ( -0.00534911   0.00511521 )
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          58.77 using 59 PHA bins.
    # Reduced chi-squared =          1.031 for     57 degrees of freedom 
    # Null hypothesis probability =   4.104526e-01
     
    Photon flux (15-150 keV)    in 1 sec: 2.49371 ( -0.584943  0.588968 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 2.50377e-07 ( -5.84147e-08  5.87157e-08 ) ergs/cm2
     
    
    Cutoff power-law model
    Time interval is from   -0.244 sec. to    0.756 sec.
    Spectral model in the cutoff power-law:
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    Photon index: 0.799649     ( -1.26953   0.42633 )
    Epeak [keV] : 9987.04      ( -9999.35 -9999.35 )
    Norm@50keV  : 2.25563E-02    ( -0.00487193   0.0449167 )
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          58.87 using 59 PHA bins.
    # Reduced chi-squared =          1.051 for     56 degrees of freedom 
    # Null hypothesis probability =   3.710118e-01
     
    Photon flux (15-150 keV)    in 1 sec: 2.50369 ( -0.59616  0.57882 ) ph/cm2/s
    Energy fluence (15-150 keV)             : 2.50509e-07 ( -5.828e-08  5.8155e-08 ) ergs/cm2
     
    
    Band function
    Time interval is from   -0.244 sec. to    0.756 sec.
     
    Spectral model in the Band function:
    ------------------------------------------------------------
    Parameters  : value       lower 90%   higher 90%
    alpha       : 5.00000   ( -5   -5 )
    beta        : -0.958749    ( -0.528885   0.503118 )
    Epeak [keV] : 33.4241      ( -33.4238 43.8672 )
    Norm@50keV   : 255.568    ( -55.9715   4.44669e+06 )
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          58.03 using 59 PHA bins.
    # Reduced chi-squared =          1.055 for     55 degrees of freedom 
    # Null hypothesis probability =   3.643915e-01
     
    Photon flux (15-150 keV)    in 1 sec:  (    ) ph/cm2/s
    Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
     
    
    Single BB
     
    Spectral model blackbody:
    ------------------------------------------------------------
    Parameters  : value    Lower 90%  Upper 90%
    kT [keV]    : 28.0339  (-8.28226  15.9844)
    R^2/D10^2   : 4.41843E-02  (-0.031397   0.0820026)
    (R is the radius in km and D10 is the distance to the source in units of 10 kpc)
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          64.24 using 59 PHA bins.
    # Reduced chi-squared =          1.127 for     57 degrees of freedom 
    # Null hypothesis probability =   2.379542e-01
     
    Energy  Fluence     90% Error
    [keV]   [erg/cm2]   [erg/cm2]
    15- 25  5.658e-09   2.972e-09
    25- 50  3.390e-08   1.615e-08
    50-150  1.927e-07   1.023e-07
    15-150  2.322e-07   1.091e-07
    
    Thermal bremsstrahlung (OTTB)
     
     
    Spectral model: thermal bremsstrahlung
    ------------------------------------------------------------
    Parameters  : value         Lower 90%    Upper 90%
    kT [keV]    : 200.000       (      )
    Norm        : 10.1508       (-2.43708     2.4369)
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          67.44 using 59 PHA bins.
    # Reduced chi-squared =          1.183 for     57 degrees of freedom 
    # Null hypothesis probability =   1.621533e-01
     
    Energy  Fluence     90% Error
    [keV]   [erg/cm2]   [erg/cm2]
    15- 25  2.527e-08   1.508e-08
    25- 50  4.862e-08   2.843e-08
    50-150  1.066e-07   6.380e-08
    15-150  1.805e-07   1.088e-07
    
    Double BB
     
     
    Spectral model: bbodyrad<1> + bbodyrad<2>
    ------------------------------------------------------------
    Parameters  : value         Lower 90%    Upper 90%
    kT1 [keV]   : 9.03792        (-3.36972      8.34988)
    R1^2/D10^2  : 1.01971        (-0.844017      3.76908)
    kT2 [keV]   : 76.3116        (-76.6853      -76.6854)
    R2^2/D10^2  : 3.01366E-03    (-0.00239286   0.0217298)
    ------------------------------------------------------------
    #Fit statistic : Chi-Squared =          56.73 using 59 PHA bins.
    # Reduced chi-squared =          1.031 for     55 degrees of freedom 
    # Null hypothesis probability =   4.103207e-01
     
    Energy  Fluence     90% Error
    [keV]   [erg/cm2]   [erg/cm2]
    15- 25  1.761e-08   1.072e-08
    25- 50  4.534e-08   2.665e-08
    50-150  1.931e-07   1.084e-07
    15-150  2.561e-07   1.390e-07
    

    S(25-50 keV) vs. S(50-100 keV) plot

    S(25-50 keV)  = 3.44e-08
    S(50-100 keV) = 9.13e-08
    

    T90 vs. Hardness ratio plot

    T90                                   = 0.64 sec.
    Hardness ratio (energy fluence ratio) = 2.65407
    

    Color vs. Color plot

    Count Ratio  (25-50 keV) / (15-25 keV) = 1.88
    Count Ratio (50-100 keV) / (15-25 keV) = 1.98
    

    Mask shadow pattern

    IMX = 0.692688935943, IMY = -0.712609536878
    

    TIME vs. PHA plot around the beginning of event data (event_start to event_start+0.64s)

    TIME vs. DetID plot around the beginning of event data (event_start to event_start+0.64s)

    100 us light curve (15-350 keV; (event_start to event_start+0.64s)

    Spacecraft aspect plot

    Bright source in the event data image

    Event data image of 15-350 keV band

    Time interval of the image:
    -2.560000 7.350000
     
    # RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
    #  [deg]    [deg]    ['] [deg]  [deg]                   [']
    135.6950 -40.5227    4.9  49.9 -167.0   0.1799   2.4    7.8	Vela X-1                      
     30.9539 -16.9875    2.7  44.8   45.8   0.5087   4.2 ------	UNKNOWN                       
    130.2664 -26.7020    2.5  57.1  177.3   0.8499   4.5 ------	UNKNOWN                       
    346.0384 -28.0000    2.2  58.4   -7.0   1.0290   5.3 ------	UNKNOWN                       
    317.4998 -65.7885    3.1  45.2  -58.4   0.4955   3.8 ------	UNKNOWN                       
    
    Webpage updated on:
    Wed Jul 15 00:18:50 EDT 2015