GRB160625A: 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: Fri Jul 15 14:18:29 EDT 2016
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger701503
======================================================================

  Trigger: 00701503      Segment: 000

  BAT Trigger Time: 488587247.936   [s; MET]
      Trigger Stop: 488587248.96   [s; MET]
               UTC: 2016-06-25T22:40:31.466540    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 176.936915418812   Dec: -65.1138111609725  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    8.86
     Image Trigger?:     NO
     Rate S/N Ratio:     15.3622914957372  [ if not an image trigger ]
     Image S/N Ratio:    8.86

  Analysis Position:   [ source = BAT ]
    RA: 176.936915418812   Dec: -65.1138111609725  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 176.938977169425   Dec: -65.1419065043362  [deg; J2000]  
        { 11h 47m 45.4s , -65d 08' 30.9" }
         +/- 0.798197129754722 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.195796794885138 [arcmin] (formal 1-sigma fit error)
    SNR: 41.9721296814664
 
  Angular difference between the analysis and refined position is 1.686523 arcmin
 
  Partial Coding Fraction: 0.5703125    [ including projection effects ]

  Duration
     T90: 53.9199999570847 +/- 3.0991353106272
        Measured from: -9.33200001716614
                   to: 44.5879999399185     [s; relative to TRIGTIME]
     T50: 31.9519999027252 +/- 0.792131237689915
        Measured from: 2.45600003004074
                   to: 34.407999932766     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 35.0720000267029     
                   to: 36.0720000267029     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -15.0360000133514     
                   to: 47.4120000004768     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     2.276958   2.376192   1.161156   0.254559
           0.060521   0.062318   0.053674   0.045919 [error]
 Peak      0.116273   0.134631   0.070410   0.016241
           0.009058   0.009409   0.007885   0.005802 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   62.448  -15.036   47.412
T90    53.920   -9.332   44.588
T50    31.952    2.456   34.408
Peak    1.000   35.072   36.072
 
 
====== 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      -2.086    -0.075      0.074       -           -               -         5.70e-03     -2.35e-04          2.33e-04      37.660   57
CPL     -1.917    -0.175      0.309       22.709     -20.968        27.225      7.01e-03        N/A               N/A         36.670   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      -1.970     -0.151     0.146       -           -               -         2.03e-02     -1.97e-03          1.94e-03      53.890   57
CPL     -1.633     -0.552     0.639       47.654      N/A           N/A         3.14e-02        N/A               N/A         52.850   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   7.91e-07  1.02e-06  9.60e-07  1.60e-06  3.31e-06  4.37e-06   erg/cm2
      90%_error_low -4.84e-08 -3.68e-08 -5.55e-08 -1.88e-07 -1.26e-07 -2.37e-07   erg/cm2
      90%_error_hi   4.95e-08  3.68e-08  5.57e-08  2.05e-07  1.26e-07  2.48e-07   erg/cm2
Peak flux       PL   1.31e+00  1.00e+00  5.12e-01  3.75e-01  3.00e+00  3.20e+00   ph/cm2/s
      90%_error_low -1.58e-01 -8.14e-02 -6.48e-02 -8.45e-02 -2.47e-01 -2.60e-01   ph/cm2/s
      90%_error_hi   1.63e-01  8.14e-02  6.49e-02  9.80e-02  2.47e-01  2.60e-01   ph/cm2/s
 
Fluence        CPL    N/A      N/A      N/A      N/A      N/A      N/A      erg/cm2
      90%_error_low -4.84e-08 -3.68e-08 -5.55e-08 -1.88e-07 -1.26e-07 -2.37e-07   erg/cm2
      90%_error_hi   4.95e-08  3.68e-08  5.57e-08  2.05e-07  1.26e-07  2.48e-07   erg/cm2
Peak flux      CPL   1.27e+00  1.04e+00  5.15e-01  2.39e-01  2.97e+00  3.06e+00   ph/cm2/s
      90%_error_low -1.79e-01 -1.04e-01 -6.91e-02 -1.28e-01 -2.54e-01 -2.95e-01   ph/cm2/s
      90%_error_hi   1.81e-01  1.08e-01  6.90e-02  1.71e-01  2.54e-01  3.50e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  176.9390   -65.1419   0.0046    32.6557    26.2261         6.2026132     41.972 TRIG_00701503                 
 
Foreground time interval of the image:
-15.036  47.412 (delta_t =  62.448 [sec])
Background time interval of the image:
-223.635 -15.036 (delta_t = 208.599 [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  -15.036 sec. to   47.412 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.08572     ( -0.0749813   0.0738729 )
Norm@50keV  : 5.70478E-03    ( -0.000234604   0.000232899 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          37.66 using 59 PHA bins.
# Reduced chi-squared =         0.6607 for     57 degrees of freedom 
# Null hypothesis probability =   9.775503e-01
 
Photon flux (15-150 keV)    in 62.45 sec: 0.891310 ( -0.034842  0.034995 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.30623e-06 ( -1.25676e-07  1.26208e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -15.036 sec. to   47.412 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.91665     ( -0.17478   0.308917 )
Epeak [keV] : 22.7086      ( -20.9684 27.2246 )
Norm@50keV  : 7.00540E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          36.67 using 59 PHA bins.
# Reduced chi-squared =         0.6548 for     56 degrees of freedom 
# Null hypothesis probability =   9.787289e-01
 
Photon flux (15-150 keV)    in 62.45 sec: 0.879768 ( -0.039735  0.037141 ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   35.072 sec. to   36.072 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.97037     ( -0.151224   0.145685 )
Norm@50keV  : 2.02823E-02    ( -0.00197016   0.00193653 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          53.89 using 59 PHA bins.
# Reduced chi-squared =         0.9455 for     57 degrees of freedom 
# Null hypothesis probability =   5.923430e-01
 
Photon flux (15-150 keV)    in 1 sec: 3.00186 ( -0.24693  0.24711 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.86819e-07 ( -1.72994e-08  1.74865e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   35.072 sec. to   36.072 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.63316     ( -0.55225   0.638772 )
Epeak [keV] : 47.6538      (   )
Norm@50keV  : 3.13839E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          52.85 using 59 PHA bins.
# Reduced chi-squared =         0.9437 for     56 degrees of freedom 
# Null hypothesis probability =   5.949192e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.96580 ( -0.25431  0.25412 ) ph/cm2/s
Energy fluence (15-150 keV)             : 0 ( 0  0 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 53.92 sec.
Hardness ratio (energy fluence ratio) = 0.942344944792

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

S(15-50 keV)  = 1.8100019e-06
S(50-150 keV) = 1.4962523e-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 = 5.749219583029950E-01, IMY = -2.832223970030819E-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:
-223.635410 -15.036000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.6279 -40.5209    4.4  39.0  -32.7   0.7680   2.6    5.0	Vela X-1                      
170.5794 -60.6355    6.4  34.2   16.9   0.4394   1.8    7.8	Cen X-3                       
186.6440 -62.7894    3.7  37.1   29.6   0.9524   3.1    1.2	GX 301-2                      
 38.3719 -29.7494    2.7  47.4 -160.9   1.6146   4.2 ------	UNKNOWN                       
 37.1204 -21.0731    3.2  55.9 -158.6   3.4513   3.6 ------	UNKNOWN                       

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

Time interval of the image:
-15.036000 47.412000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
135.5975 -40.3913    0.0  39.2  -32.8  -0.1867  -1.2   10.3	Vela X-1                      
170.6001 -60.6056    7.7  34.3   16.9  -0.2163  -1.5    8.4	Cen X-3                       
186.5725 -62.7819    7.5  37.1   29.5  -0.2734  -1.5    2.4	GX 301-2                      
298.8094 -68.0625    2.4  40.7   96.2   2.2284   4.7 ------	UNKNOWN                       
184.5102 -47.8549    2.0  49.3   16.7   1.6375   5.8 ------	UNKNOWN                       
176.9390 -65.1419    0.3  32.7   26.2   6.2028  42.0 ------	UNKNOWN                       
 16.5637 -45.1538    2.6  40.8  167.0   0.8387   4.5 ------	UNKNOWN                       
101.1241 -66.0845    2.8   7.0  -31.1   0.4001   4.1 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image: