GRB150801B: Summary Image Light curves Spectra Distribution Others

Analysis Summary

Notes:

• 1) No attempt has been made to eliminate the non-significant decimal places.
• 2) This batgrbproduct analysis is done using the HEASARC data.
• 3) This batgrbproduct analysis is using the flight position for the mask-weighting calculation.

======================================================================
                  BAT GRB EVENT DATA PROCESSING REPORT
    Process Script Ver: batgrbproduct v2.46
    Process Start Time: Sun Aug 30 18:11:46 EDT 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger650977
======================================================================

  Trigger: 00650977      Segment: 000

  BAT Trigger Time: 460161723.584   [s; MET]
      Trigger Stop: 460161723.84   [s; MET]
               UTC: 2015-08-01T22:41:48.648820    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 82.9589982137698   Dec: -5.38743125075409  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.7
     Image Trigger?:     NO
     Rate S/N Ratio:     13  [ if not an image trigger ]
     Image S/N Ratio:    7.7

  Analysis Position:   [ source = BAT ]
    RA: 82.9589982137698   Dec: -5.38743125075409  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 82.9607296632042   Dec: -5.37529810147569  [deg; J2000]  
        { 05h 31m 50.6s , -05d 22' 31.1" }
         +/- 1.3429923556643 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.414382360656706 [arcmin] (formal 1-sigma fit error)
    SNR: 19.9597997130576
 
  Angular difference between the analysis and refined position is 0.735300 arcmin
 
  Partial Coding Fraction: 0.625    [ including projection effects ]

  Duration
     T90: 408.707999944687 +/- 29.6191441817222
        Measured from: 0.244000017642975
                   to: 408.95199996233     [s; relative to TRIGTIME]
     T50: 364.887999951839 +/- 6.82123977976951
        Measured from: 6.18800002336502
                   to: 371.075999975204     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 9.32400000095367     
                   to: 10.3240000009537     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -30.1599999666214     
                   to: 433.944000005722     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.800035   1.907614   1.258471   0.267568
           0.120211   0.123025   0.105050   0.088122 [error]
 Peak      0.093393   0.109836   0.072101   0.012204
           0.008300   0.008932   0.007570   0.005542 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  464.104  -30.160  433.944
T90   408.708    0.244  408.952
T50   364.888    6.188  371.076
Peak    1.000    9.324   10.324
 
 
====== 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      -1.796    -0.139      0.136       -           -               -         6.90e-04     -5.53e-05          5.45e-05      50.270   57
CPL     -1.798    -0.137      0.311     9999.340    -9999.330      -9999.340      6.90e-04     -3.56e-04          4.01e-04      50.280   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      -1.819     -0.157     0.152       -           -               -         1.84e-02     -1.84e-03          1.81e-03      63.320   57
CPL     -1.331     -0.574     0.727       61.886     -17.213       -61.886      3.41e-02     -1.66e-02          5.14e-02      61.490   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   5.40e-07  8.29e-07  9.54e-07  2.11e-06  2.95e-06  4.43e-06   erg/cm2
      90%_error_low -6.19e-08 -5.91e-08 -1.05e-07 -4.51e-07 -2.40e-07 -5.51e-07   erg/cm2
      90%_error_hi   6.39e-08  5.91e-08  1.06e-07  5.28e-07  2.43e-07  6.11e-07   erg/cm2
Peak flux       PL   1.03e+00  8.56e-01  4.85e-01  4.08e-01  2.55e+00  2.78e+00   ph/cm2/s
      90%_error_low -1.37e-01 -7.63e-02 -6.27e-02 -9.42e-02 -2.28e-01 -2.46e-01   ph/cm2/s
      90%_error_hi   1.41e-01  7.62e-02  6.26e-02  1.10e-01  2.28e-01  2.46e-01   ph/cm2/s
 
Fluence        CPL   5.43e-07  8.24e-07  9.54e-07  2.10e-06  2.98e-06  4.42e-06   erg/cm2
      90%_error_low    N/A       N/A       N/A       N/A    -2.79e-07 -1.03e-06   erg/cm2
      90%_error_hi     N/A       N/A       N/A       N/A     2.08e-07  5.87e-07   erg/cm2
Peak flux      CPL   9.68e-01  9.06e-01  4.95e-01  2.23e-01  2.51e+00  2.59e+00   ph/cm2/s
      90%_error_low -1.58e-01 -9.80e-02 -6.81e-02 -1.22e-01 -2.35e-01 -2.72e-01   ph/cm2/s
      90%_error_hi   1.59e-01  1.02e-01  6.85e-02  2.23e-01  2.34e-01  3.25e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
   82.9607    -5.3753   0.0097    33.3861  -140.5415         1.8316622     19.960 TRIG_00650977                 
 
Foreground time interval of the image:
-30.160   9.717 (delta_t =  39.877 [sec])
Background time interval of the image:
-239.584 -30.160 (delta_t = 209.424 [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

Other quick-look light curves:

• 64 ms binning (zoomed)
• 16 ms binning (zoomed)
• 8 ms binning (zoomed)
• 2 ms binning (zoomed)
• SN=5 or 10 s binning (full-time range)
• Raw light curve

Spectra

Notes:

• 1) The fitting includes the systematic errors.
• 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
• 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.

Time averaged spectrum fit using the average DRM

Power-law model

Time interval is from  -30.160 sec. to  433.944 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.79645     ( -0.138793   0.135584 )
Norm@50keV  : 6.89691E-04    ( -5.53153e-05   5.45356e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          50.27 using 59 PHA bins.
# Reduced chi-squared =         0.8820 for     57 degrees of freedom 
# Null hypothesis probability =   7.235761e-01
 
Photon flux (15-150 keV)    in 464.1 sec: 9.49123E-02 ( -0.0068828  0.0068957 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.94762e-06 ( -2.4035e-07  2.42827e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -30.160 sec. to  433.944 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.7981     ( -0.137184   0.310727 )
Epeak [keV] : 9999.34      ( -9999.35 -9999.36 )
Norm@50keV  : 6.90013E-04    ( -0.000356303   0.000400575 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          50.28 using 59 PHA bins.
# Reduced chi-squared =         0.8978 for     56 degrees of freedom 
# Null hypothesis probability =   6.902938e-01
 
Photon flux (15-150 keV)    in 464.1 sec: 9.52219E-02 ( -0.0079567  0.0072201 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.97839e-06 ( -2.79274e-07  2.0802e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    9.324 sec. to   10.324 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.81896     ( -0.157302   0.152411 )
Norm@50keV  : 1.83577E-02    ( -0.00184075   0.00181407 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          63.32 using 59 PHA bins.
# Reduced chi-squared =          1.111 for     57 degrees of freedom 
# Null hypothesis probability =   2.633432e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.54862 ( -0.22784  0.22799 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.68931e-07 ( -1.70232e-08  1.72134e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    9.324 sec. to   10.324 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.33128     ( -0.57381   0.726848 )
Epeak [keV] : 61.8858      ( -17.2133 -61.8858 )
Norm@50keV  : 3.40798E-02    ( -0.0165997   0.0513672 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.49 using 59 PHA bins.
# Reduced chi-squared =          1.098 for     56 degrees of freedom 
# Null hypothesis probability =   2.860653e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.50680 ( -0.23502  0.23406 ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 408.708 sec.
Hardness ratio (energy fluence ratio) = 1.15156897251

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

S(15-50 keV)  = 1.369063e-06
S(50-150 keV) = 1.5784783e-06

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 = -5.088279037210258E-01, IMY = 4.188262261616247E-01

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:
-239.584000 -30.160000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.5630 -40.5356    2.0  44.4  -39.1   1.8918   5.6    1.9	Vela X-1                      
103.7777  -3.5790    2.7  42.4 -109.6   3.2363   4.3 ------	UNKNOWN                       
104.1965  -3.8650    3.3  42.4 -108.8   2.6177   3.6 ------	UNKNOWN                       

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

Time interval of the image:
-30.160000 9.716590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.5185 -40.4758    6.7  44.4  -39.2  -0.2534  -1.7    4.8	Vela X-1                      
 30.2486 -14.1890    2.6  47.8  136.0   1.3534   4.4 ------	UNKNOWN                       
 37.8865  -2.7494    2.6  50.4  153.8   1.3832   4.5 ------	UNKNOWN                       
 38.8438   1.9109    2.9  53.5  158.5   1.6034   4.0 ------	UNKNOWN                       
 59.9911  -7.1825    2.3  34.8  178.0   0.4353   5.0 ------	UNKNOWN                       
 82.9607  -5.3753    0.6  33.4 -140.5   1.8318  20.0 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
62.716580 962.459200
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 83.6294  22.0118    0.2  27.4 -151.4  36.0501  57.1    0.3	Crab                          
135.5623 -40.5534    5.5  58.6  -17.8   7.2764   2.1    1.5	Vela X-1                      
 62.5719 -48.5928    3.8  46.5   45.7   7.4909   3.0 ------	UNKNOWN                       
 57.6185 -30.7269    3.4  34.7   67.4   4.7678   3.4 ------	UNKNOWN                       
 69.4350   7.9832    3.0  19.0  161.9   2.3438   3.9 ------	UNKNOWN                       
 82.9365  -5.4220    2.0   0.0   65.1   3.4084   5.8 ------	UNKNOWN