Analysis Summary

Notes:

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Mon Jul 15 18:52:15 EDT 2019
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger907754
======================================================================

  Trigger: 00907754      Segment: 000

  BAT Trigger Time: 581858888.768   [s; MET]
      Trigger Stop: 581858889.792   [s; MET]
               UTC: 2019-06-10T11:27:45.716980    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 46.2887188080502   Dec: -7.66601686408089  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    9.91
     Image Trigger?:     NO
     Rate S/N Ratio:     45.8693797647189  [ if not an image trigger ]
     Image S/N Ratio:    9.91

  Analysis Position:   [ source = BAT ]
    RA: 46.2887188080502   Dec: -7.66601686408089  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 46.2392938192449   Dec: -7.65968343888696  [deg; J2000]  
        { 03h 04m 57.4s , -07d 39' 34.9" }
         +/- 1.83290769234039 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.8862085675582 [arcmin] (formal 1-sigma fit error)
    SNR: 12.7998018316262
 
  Angular difference between the analysis and refined position is 2.963482 arcmin
 
  Partial Coding Fraction: 1.015625    [ including projection effects ]

  Duration
     T90: 0.631999969482422 +/- 0.100657807530861
        Measured from: 0.248000025749207
                   to: 0.879999995231628     [s; relative to TRIGTIME]
     T50: 0.363999962806702 +/- 0.0905096828275688
        Measured from: 0.360000014305115
                   to: 0.723999977111816     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 0.0820000171661377     
                   to: 1.08200001716614     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 0.212000012397766     
                   to: 0.952000021934509     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.072293   0.104260   0.206245   0.143586
           0.016182   0.020988   0.019321   0.023018 [error]
 Peak      0.070520   0.130288   0.225724   0.132094
           0.018500   0.023967   0.021644   0.026309 [error]

     [ fluence units of on-axis counts / fully illuminated detector ] 

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    0.740    0.212    0.952
T90     0.632    0.248    0.880
T50     0.364    0.360    0.724
Peak    1.000    0.082    1.082
 
 
====== Spectral Analysis Summary =====================================
 
Model      : spectral model: simple power-law (PL) and cutoff power-law (CPL)
Ph_index   : photon index: E^{Ph_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 both the PL model and CPL model
Nomr_90err : 90% error of the normalization
chi2       : Chi-Squared
dof        : degree of freedo
 
=== Time-averaged spectral analysis ===
(Best model with acceptable fit: PL)
 
Model Ph_index Ph_90err_low Ph_90err_hi  Epeak  Epeak_90err_low  Epeak_90err_hi  Norm       Nomr_90err_low    Norm_90err_hi    chi2    dof
PL      -0.314    -0.250      0.277       -           -               -         3.96e-02     -6.25e-03          5.92e-03      56.550   57
CPL     -0.195    -0.360      0.694      998.872    -998.872      -998.872      4.39e-02     -9.79e-03          2.38e-02      56.900   56
 
 
=== 1-s peak spectral analysis ===
(Best model with acceptable fit: PL)
 
Model Ph_index Ph_90err_low Ph_90err_hi  Epeak  Epeak_90err_low  Epeak_90err_hi  Norm       Nomr_90err_low    Norm_90err_hi    chi2    dof
PL      -0.414     -0.243     0.267       -           -               -         3.31e-02     -4.99e-03          4.78e-03      59.020   57
CPL     -0.380     -0.269     0.264     9777.610    -9777.610      -9777.610      3.32e-02     -4.76e-03          4.24e-03      59.040   56
 
 
=== 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         PL   1.25e-08  4.80e-08  1.55e-07  1.63e-06  4.35e-07  1.84e-06   erg/cm2
      90%_error_low -4.11e-09 -1.01e-08 -1.78e-08 -4.52e-07 -5.34e-08 -4.55e-07   erg/cm2
      90%_error_hi   4.81e-09  9.93e-09  1.78e-08  6.07e-07  5.36e-08  6.02e-07   erg/cm2
Peak flux       PL   4.87e-01  9.44e-01  1.42e+00  4.60e+00  3.99e+00  7.45e+00   ph/cm2/s
      90%_error_low -1.55e-01 -1.95e-01 -1.69e-01 -1.19e+00 -4.95e-01 -1.19e+00   ph/cm2/s
      90%_error_hi   1.79e-01  1.93e-01  1.69e-01  1.53e+00  4.98e-01  1.40e+00   ph/cm2/s
 
Fluence        CPL   1.25e-08  4.83e-08  1.55e-07  1.63e-06  4.36e-07  1.83e-06   erg/cm2
      90%_error_low    N/A       N/A       N/A    -8.53e-07 -7.03e-08 -8.14e-07   erg/cm2
      90%_error_hi     N/A       N/A       N/A     5.92e-07  6.91e-08  2.55e-07   erg/cm2
Peak flux      CPL   4.81e-01  9.44e-01  1.42e+00  4.55e+00  3.98e+00  6.97e+00   ph/cm2/s
      90%_error_low -2.20e-01 -2.04e-01 -1.73e-01 -2.13e+00 -5.18e-01 -2.20e+00   ph/cm2/s
      90%_error_hi   1.31e-01  1.89e-01  2.24e-01  8.42e-01  5.01e-01  1.76e+00   ph/cm2/s
 
======================================================================
  • Special notes of this burst




    Image

    Pre-slew 15.0-350.0 keV image (Event data)

    #   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
   46.2393    -7.6597   0.0151    13.5659   -22.9125         0.5577189     12.800 TRIG_00907754                 
 
Foreground time interval of the image:
  0.212   0.952 (delta_t =   0.740 [sec])
Background time interval of the image:
-61.067   0.212 (delta_t =  61.279 [sec])




    Light Curves

    Note: The mask-weighted lightcurves have units of either count/det or counts/sec/det, where a det is 0.4 x 0.4 = 0.16 sq cm.

    Full-time range; 1 s binning

    Bokeh Plot

    Other quick-look light curves:




    Spectra

    Notes:

    Time averaged spectrum fit using the average DRM

    Power-law model
    Time interval is from    0.212 sec. to    0.952 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.314011     ( -0.249946   0.277123 )
Norm@50keV  : 3.96473E-02    ( -0.00625401   0.0059235 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          56.55 using 59 PHA bins.
# Reduced chi-squared =         0.9922 for     57 degrees of freedom 
# Null hypothesis probability =   4.917746e-01
 
Photon flux (15-150 keV)    in 0.74 sec: 4.87466 ( -0.59017  0.59267 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.35133e-07 ( -5.34242e-08  5.35892e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from    0.212 sec. to    0.952 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.301693     ( -0.359591   0.693465 )
Epeak [keV] : 9999.24      ( -9999.29 -9999.29 )
Norm@50keV  : 4.00150E-02    ( -0.00586857   0.0276726 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          56.58 using 59 PHA bins.
# Reduced chi-squared =          1.010 for     56 degrees of freedom 
# Null hypothesis probability =   4.531118e-01
 
Photon flux (15-150 keV)    in 0.74 sec: 4.87243 ( -0.58997  0.59238 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.35785e-07 ( -7.03061e-08  6.90763e-08 ) ergs/cm2

    1-s peak spectrum fit

    Power-law model
    Time interval is from    0.082 sec. to    1.082 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.414109     ( -0.242556   0.267046 )
Norm@50keV  : 3.31416E-02    ( -0.00499291   0.00478189 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.02 using 59 PHA bins.
# Reduced chi-squared =          1.035 for     57 degrees of freedom 
# Null hypothesis probability =   4.016008e-01
 
Photon flux (15-150 keV)    in 1 sec: 3.98655 ( -0.49481  0.49756 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.65575e-07 ( -5.94965e-08  5.98128e-08 ) ergs/cm2
    Cutoff power-law model
    Time interval is from    0.082 sec. to    1.082 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.403377     ( -0.268982   0.264514 )
Epeak [keV] : 9999.99      ( -9999.99 -9999.99 )
Norm@50keV  : 3.34446E-02    ( -0.00501929   0.00398133 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          59.02 using 59 PHA bins.
# Reduced chi-squared =          1.054 for     56 degrees of freedom 
# Null hypothesis probability =   3.658732e-01
 
Photon flux (15-150 keV)    in 1 sec: 3.98169 ( -0.51816  0.50085 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.89756e-07 ( -9.07311e-08  4.02246e-08 ) ergs/cm2

    Time-resolved spectra




    Distribution

    T90 vs. Hardness ratio plot 

    T90                                   = 0.632 sec.
Hardness ratio (energy fluence ratio) = 3.21758580313

    S(15-50 keV) vs. S(50-150 keV) plot 

    S(15-50 keV)  = 6.054599e-08
S(50-150 keV) = 3.745784e-07

    The dash-dotted line and the dashed line traces the fluences calculated from the Band function with Epeak = 15 and 150 keV, respectively. Both lines assume a canonical values of alpha = -1 and beta = -2.5.




    Mask shadow pattern 

    IMX = 2.222568407191748E-01, IMY = 9.394200137702663E-02

    Spacecraft aspect plot

    Bright source in the pre-burst/pre-slew/post-slew images

    Pre-burst image of 15-350 keV band 

    Time interval of the image:
-61.067400 0.212000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 36.1037  -4.2547    3.0   4.4   18.0   9.3288   3.9 ------	UNKNOWN                       
 70.7106   0.5090    2.2  35.7  -58.4  24.6855   5.2 ------	UNKNOWN

    Pre-slew background subtracted image of 15-350 keV band 

    Time interval of the image:
0.212000 0.952000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
348.4106  13.1751    2.3  48.0  140.4   1.1739   4.9 ------	UNKNOWN                       
348.1015  20.6127    2.2  50.2  149.8   1.1720   5.2 ------	UNKNOWN                       
 46.2393  -7.6597    0.9  13.6  -22.9   0.5577  12.8 ------	UNKNOWN                       
 32.5023  46.4351    2.3  46.5 -149.9   0.4758   5.1 ------	UNKNOWN                       
 83.2130  -4.9456    2.1  48.4  -50.9   1.1542   5.5 ------	UNKNOWN

    Post-slew image of 15-350 keV band 

    Time interval of the image:
-487.768000 -407.578000
-239.768000 62.302000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
268.3697  -1.4799    8.5  40.7  123.3 -29.6473  -1.4    1.6	SW J1753.5-0127               
273.9842 -14.0373    8.9  36.7  102.2 -22.8440  -1.3    1.3	GX 17+2                       
284.8828 -24.8790    5.0  32.6   76.7 -31.4661  -2.3    8.7	HT1900.1-2455                 
288.7086  10.8251    6.6  24.1  156.0  13.7823   1.8    9.0	GRS 1915+105                  
299.5874  35.3723    7.5  38.6 -159.4  15.0813   1.5   10.2	Cyg X-1                       
308.0080  40.9224   31.8  43.1 -148.2  -4.5848  -0.4    5.0	Cyg X-3                       
326.4424  38.2594    0.0  43.5 -127.1  30.4230   1.5   13.3	Cyg X-2                       
310.2278  -6.3780    3.1   4.4   18.0  24.6840   3.8 ------	UNKNOWN