GRB160826A: 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 Sep 11 20:47:54 EDT 2016
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger709907
======================================================================

  Trigger: 00709907      Segment: 000

  BAT Trigger Time: 493884775.04   [s; MET]
      Trigger Stop: 493884787.2   [s; MET]
               UTC: 2016-08-26T06:12:38.274100    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 183.073929859613   Dec: -67.6888587210817  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    9.26
     Image Trigger?:     NO
     Rate S/N Ratio:     10.4403065089106  [ if not an image trigger ]
     Image S/N Ratio:    9.26

  Analysis Position:   [ source = BAT ]
    RA: 183.073929859613   Dec: -67.6888587210817  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 183.134841711261   Dec: -67.6547689000202  [deg; J2000]  
        { 12h 12m 32.4s , -67d 39' 17.2" }
         +/- 2.75304004480357 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.4334309428382 [arcmin] (formal 1-sigma fit error)
    SNR: 7.1583803091008
 
  Angular difference between the analysis and refined position is 2.472135 arcmin
 
  Partial Coding Fraction: 1.015625    [ including projection effects ]

  Duration
     T90: 52.6159999370575 +/- 14.392495407259
        Measured from: 4.77999997138977
                   to: 57.3959999084473     [s; relative to TRIGTIME]
     T50: 14.9519999623299 +/- 12.6993929121423
        Measured from: 8.92799997329712
                   to: 23.879999935627     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 4.63999998569489     
                   to: 5.63999998569489     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 3.84799998998642     
                   to: 61.6079999804497     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.282124   0.291557   0.208212   0.113688
           0.046601   0.046867   0.040127   0.035569 [error]
 Peak     -0.000089   0.029104   0.024741   0.003581
           0.006198   0.006313   0.005428   0.004776 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   57.760    3.848   61.608
T90    52.616    4.780   57.396
T50    14.952    8.928   23.880
Peak    1.000    4.640    5.640
 
 
====== 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: N/A)
 
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      -1.546    -0.292      0.286       -           -               -         8.91e-04     -1.54e-04          1.51e-04      71.960   57
CPL     -1.442    -1.259      1.153      230.544    -230.544      -230.544      1.01e-03     -2.73e-04          3.08e-03      71.940   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      -1.089     -0.460     0.502       -           -               -         3.86e-03     -1.14e-03          1.13e-03      68.960   57
CPL      0.605     -2.863     3.573       78.271     -23.443       -78.271      2.64e-02     -2.64e-02          1.97e+00      67.090   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   6.86e-08  1.23e-07  1.68e-07  4.77e-07  4.85e-07  8.36e-07   erg/cm2
      90%_error_low -1.73e-08 -2.00e-08 -3.86e-08 -1.95e-07 -9.10e-08 -2.34e-07   erg/cm2
      90%_error_hi   1.82e-08  1.99e-08  3.85e-08  2.72e-07  9.31e-08  2.98e-07   erg/cm2
Peak flux       PL   1.07e-01  1.38e-01  1.30e-01  2.15e-01  4.47e-01  5.90e-01   ph/cm2/s
      90%_error_low -5.38e-02 -4.92e-02 -4.12e-02 -1.11e-01 -1.34e-01 -1.74e-01   ph/cm2/s
      90%_error_hi   6.46e-02  4.82e-02  4.08e-02  1.72e-01  1.36e-01  1.87e-01   ph/cm2/s
 
Fluence        CPL   6.77e-08  1.24e-07  1.69e-07  3.94e-07  4.80e-07  6.99e-07   erg/cm2
      90%_error_low -1.95e-08 -2.15e-08 -3.93e-08 -2.34e-07 -1.02e-07 -2.87e-07   erg/cm2
      90%_error_hi   1.78e-08  2.56e-08  4.03e-08  2.34e-07  9.70e-08  2.12e-07   erg/cm2
Peak flux      CPL   7.76e-02  1.59e-01  1.47e-01  5.05e-02  4.22e-01  4.34e-01   ph/cm2/s
      90%_error_low -5.39e-02 -6.06e-02 -5.50e-02 -5.05e-02 -1.34e-01 -1.44e-01   ph/cm2/s
      90%_error_hi   7.25e-02  6.76e-02  5.17e-02  2.25e-01  1.39e-01  2.51e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  183.1348   -67.6548   0.0268     7.9688  -174.4088         0.7174911      7.158 TRIG_00709907                 
 
Foreground time interval of the image:
  3.848  57.261 (delta_t =  53.413 [sec])
Background time interval of the image:
-186.139   3.848 (delta_t = 189.987 [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    3.848 sec. to   61.608 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.54573     ( -0.291974   0.28569 )
Norm@50keV  : 8.91453E-04    ( -0.00015444   0.00015144 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          71.96 using 59 PHA bins.
# Reduced chi-squared =          1.262 for     57 degrees of freedom 
# Null hypothesis probability =   8.756865e-02
 
Photon flux (15-150 keV)    in 57.76 sec: 0.112717 ( -0.0181139  0.01813 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.85096e-07 ( -9.09859e-08  9.31166e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    3.848 sec. to   61.608 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.4418     ( -1.26129   1.15157 )
Epeak [keV] : 230.544      ( -249.67 -249.67 )
Norm@50keV  : 1.01239E-03    ( -0.00027593   0.00307696 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          71.94 using 59 PHA bins.
# Reduced chi-squared =          1.285 for     56 degrees of freedom 
# Null hypothesis probability =   7.421404e-02
 
Photon flux (15-150 keV)    in 57.76 sec: 0.112230 ( -0.0186603  0.01844 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.79995e-07 ( -1.02486e-07  9.70328e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    4.640 sec. to    5.640 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.08928     ( -0.460618   0.501609 )
Norm@50keV  : 3.85710E-03    ( -0.00113584   0.00113168 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          68.96 using 59 PHA bins.
# Reduced chi-squared =          1.210 for     57 degrees of freedom 
# Null hypothesis probability =   1.330817e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.446923 ( -0.134245  0.135563 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.04725e-08 ( -1.25052e-08  1.27396e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    4.640 sec. to    5.640 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: 0.604773     ( -2.86302   3.57281 )
Epeak [keV] : 78.2712      ( -23.4428 -78.2706 )
Norm@50keV  : 2.64266E-02    ( -0.0264267   1.96732 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          67.09 using 59 PHA bins.
# Reduced chi-squared =          1.198 for     56 degrees of freedom 
# Null hypothesis probability =   1.474083e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.421693 ( -0.134297  0.138594 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.56517e-08 ( -1.34682e-08  1.43287e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = N/A sec.
Hardness ratio (energy fluence ratio) = N/A

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

S(15-50 keV)  = N/A
S(50-150 keV) = N/A

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 = -1.393194532726136E-01, IMY = 1.363878790837431E-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:
-186.139400 3.848000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.3947 -40.5103   23.2  42.5 -128.6   0.2432   0.5    6.7	Vela X-1                      
170.2590 -60.5820    1.8  13.3 -133.0   1.2349   6.3    3.0	Cen X-3                       
186.4894 -62.9122    4.5   5.3 -136.9   0.5004   2.6    9.7	GX 301-2                      
255.9896 -37.8438    2.6  42.5   42.5   2.0422   4.5    0.1	4U 1700-377                   
256.3928 -36.3909   21.1  43.8   41.7  -0.2651  -0.5    2.8	GX 349+2                      
264.8438 -44.3119   12.9  41.4   56.4   0.5444   0.9    9.3	4U 1735-44                    
 69.6414 -53.5838    2.2  56.9  174.1   6.6811   5.3 ------	UNKNOWN                       
184.4369 -71.1022    2.9   9.9  166.8   0.7209   4.0 ------	UNKNOWN                       
135.8352 -72.9310    2.4  24.2  179.7   1.0166   4.7 ------	UNKNOWN                       

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

Time interval of the image:
3.848000 57.260590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.3878 -40.4301    0.0  42.6 -128.6  -0.2296  -1.0    9.9	Vela X-1                      
170.3058 -60.6514   34.1  13.3 -133.2   0.0335   0.3    1.7	Cen X-3                       
186.6954 -62.5589    0.0   5.3 -133.0   0.1280   1.3   12.7	GX 301-2                      
255.9964 -37.9778    6.8  42.3   42.7   0.4388   1.7    8.0	4U 1700-377                   
256.5710 -36.5588    5.7  43.8   42.0  -0.5797  -2.0   10.4	GX 349+2                      
264.8630 -44.5111   20.4  41.2   56.6  -0.1873  -0.6    6.3	4U 1735-44                    
221.0849 -69.6980    2.5  11.5   97.6   0.4255   4.6 ------	UNKNOWN                       
183.1349 -67.6547    1.6   8.0 -174.4   0.7175   7.2 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
88.860600 963.088200
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.4298 -40.5661    6.7  37.3 -130.2   1.8780   1.7    4.6	Vela X-1                      
170.3387 -60.5974    1.3   9.0 -106.2   5.6563   9.0    1.7	Cen X-3                       
186.5948 -62.7530    2.5   5.1  -44.0   2.8742   4.6    2.0	GX 301-2                      
256.0749 -37.8181    2.9  49.1   29.3   8.0685   4.0    4.5	4U 1700-377                   
256.2808 -36.3399    4.8  50.5   28.6  -5.7154  -2.4    9.0	GX 349+2                      
264.8957 -44.3833    8.4  46.7   41.5   2.8578   1.4    7.7	4U 1735-44                    
 75.1935 -43.0105    2.5  56.9  174.0  20.2859   4.5 ------	UNKNOWN                       
103.3524 -53.8024    3.4  38.1 -171.9   2.8848   3.4 ------	UNKNOWN                       
201.4434 -42.9766    2.7  26.6  -31.2   2.6587   4.3 ------	UNKNOWN                       
214.2925 -12.5569    3.4  58.8  -25.9  13.5663   3.4 ------	UNKNOWN                       
145.2991 -30.7025    3.6  43.1 -112.6   9.6636   3.2 ------	UNKNOWN