GRB170526A: 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: Wed Jun 21 15:49:43 EDT 2017
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger754549
======================================================================

  Trigger: 00754549      Segment: 000

  BAT Trigger Time: 517498528.064   [s; MET]
      Trigger Stop: 517498533.568   [s; MET]
               UTC: 2017-05-26T13:35:08.944680    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 4.7079606442867   Dec: 1.23959674361896  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    6.86
     Image Trigger?:     NO
     Rate S/N Ratio:     8.88819441731559  [ if not an image trigger ]
     Image S/N Ratio:    6.86

  Analysis Position:   [ source = BAT ]
    RA: 4.7079606442867   Dec: 1.23959674361896  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 4.72206259301582   Dec: 1.26388451149915  [deg; J2000]  
        { 00h 18m 53.3s , +01d 15' 50.0" }
         +/- 2.28072571444758 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.20631337243499 [arcmin] (formal 1-sigma fit error)
    SNR: 9.36667471572096
 
  Angular difference between the analysis and refined position is 1.684992 arcmin
 
  Partial Coding Fraction: 0.9453125    [ including projection effects ]

  Duration
     T90: 8.31199997663498 +/- 2.44560012871808
        Measured from: 0.163999974727631
                   to: 8.47599995136261     [s; relative to TRIGTIME]
     T50: 3.77199989557266 +/- 1.805454017922
        Measured from: 1.77200001478195
                   to: 5.54399991035461     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 1.53200000524521     
                   to: 2.53200000524521     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -0.0720000267028809     
                   to: 8.71599996089935     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.085131   0.071122   0.087485   0.017796
           0.016827   0.017383   0.015037   0.012617 [error]
 Peak      0.021345   0.008570   0.020577   0.004346
           0.005770   0.006147   0.005220   0.004244 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    8.788   -0.072    8.716
T90     8.312    0.164    8.476
T50     3.772    1.772    5.544
Peak    1.000    1.532    2.532
 
 
====== 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      -1.118    -0.385      0.408       -           -               -         1.99e-03     -3.73e-04          3.70e-04      62.240   57
CPL     -1.148    -0.355      0.448     9999.360    -9999.360      -9999.360      2.00e-03     -3.72e-04          -2.00e-03      62.290   56
 
 
=== 1-s peak 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      -1.552     -0.782     0.679       -           -               -         3.26e-03     -1.32e-03          1.16e-03      73.690   57
CPL     -1.545     -1.956     1.132     9999.360      N/A           N/A         3.27e-03        N/A               N/A         73.700   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   1.56e-08  3.63e-08  6.69e-08  2.95e-07  1.82e-07  4.14e-07   erg/cm2
      90%_error_low -6.19e-09 -8.91e-09 -1.53e-08 -1.35e-07 -3.77e-08 -1.45e-07   erg/cm2
      90%_error_hi   7.04e-09  8.28e-09  1.45e-08  2.08e-07  3.80e-08  2.09e-07   erg/cm2
Peak flux       PL   1.41e-01  1.37e-01  9.38e-02  1.00e-01  4.12e-01  4.73e-01   ph/cm2/s
      90%_error_low -1.41e-01 -4.88e-02 -4.87e-02 -7.56e-02 -1.37e-01 -1.62e-01   ph/cm2/s
      90%_error_hi   8.64e-02  4.65e-02  4.47e-02  1.44e-01  1.37e-01  1.68e-01   ph/cm2/s
 
Fluence        CPL   1.57e-08  3.64e-08  6.68e-08  3.05e-07  1.81e-07  4.00e-07   erg/cm2
      90%_error_low    N/A    -9.43e-09 -1.52e-08 -1.97e-07 -3.75e-08 -1.54e-07   erg/cm2
      90%_error_hi     N/A     8.48e-09  1.47e-08  2.40e-07  3.81e-08  2.19e-07   erg/cm2
Peak flux      CPL   1.30e-01  1.01e-01  5.46e-02  5.12e-02  3.05e-01  3.36e-01   ph/cm2/s
      90%_error_low -1.30e-01 -1.01e-01 -5.46e-02 -5.12e-02 -3.05e-01 -3.36e-01   ph/cm2/s
      90%_error_hi   9.13e-02  5.07e-02  2.14e-02  2.60e-02  1.47e-01  1.42e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
    4.7221     1.2639   0.0204    18.2118   158.3171         0.2992216      9.367 TRIG_00754549                 
 
Foreground time interval of the image:
 -0.072   8.716 (delta_t =   8.788 [sec])
Background time interval of the image:
-277.163 -259.056 (delta_t =  18.107 [sec])
-239.064  -0.072 (delta_t = 238.992 [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   -0.072 sec. to    8.716 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.11795     ( -0.385241   0.408326 )
Norm@50keV  : 1.98798E-03    ( -0.000373191   0.000370257 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          62.24 using 59 PHA bins.
# Reduced chi-squared =          1.092 for     57 degrees of freedom 
# Null hypothesis probability =   2.951490e-01
 
Photon flux (15-150 keV)    in 8.788 sec: 0.231007 ( -0.045264  0.045361 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.81648e-07 ( -3.77217e-08  3.79509e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -0.072 sec. to    8.716 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.11557     ( -0.357498   0.445559 )
Epeak [keV] : 1.00000E+04      ( -10000 -10000 )
Norm@50keV  : 1.99848E-03    ( -0.000370089   -0.00199847 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          62.27 using 59 PHA bins.
# Reduced chi-squared =          1.112 for     56 degrees of freedom 
# Null hypothesis probability =   2.631191e-01
 
Photon flux (15-150 keV)    in 8.788 sec: 0.231079 ( -0.045398  0.045233 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.81355e-07 ( -3.75285e-08  3.80969e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    1.532 sec. to    2.532 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.5517     ( -0.781783   0.678913 )
Norm@50keV  : 3.25643E-03    ( -0.00132059   0.00115707 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          73.69 using 59 PHA bins.
# Reduced chi-squared =          1.293 for     57 degrees of freedom 
# Null hypothesis probability =   6.761998e-02
 
Photon flux (15-150 keV)    in 1 sec: 0.412464 ( -0.136939  0.136811 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.06507e-08 ( -1.25536e-08  1.28203e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    1.532 sec. to    2.532 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.23821     ( -1.2632   1.82496 )
Epeak [keV] : 87.3210      (   )
Norm@50keV  : 1.45389E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          73.02 using 59 PHA bins.
# Reduced chi-squared =          1.304 for     56 degrees of freedom 
# Null hypothesis probability =   6.290808e-02
 
Photon flux (15-150 keV)    in 1 sec: 0.305212 ( -0.305212  0.14707 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.01398e-08 ( 0  0 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 8.312 sec.
Hardness ratio (energy fluence ratio) = 1.84314701395

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

S(15-50 keV)  = 5.189957e-08
S(50-150 keV) = 1.2974864e-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 = -3.057317270385411E-01, IMY = -1.215600449943498E-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:
-277.163400 -259.056300
-239.064000 -0.072000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 25.0810 -46.5115    2.4  40.2   39.8   2.0787   4.9 ------	UNKNOWN                       
 54.3741   3.2196    2.9  34.5  -61.5   1.3960   3.9 ------	UNKNOWN                       
 14.2269  46.3874    2.5  53.2 -142.2   5.1190   4.6 ------	UNKNOWN                       

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

Time interval of the image:
-0.072000 8.716000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
 23.1889 -55.1164    1.7  48.7   42.4   1.0306   6.9 ------	UNKNOWN                       
 65.3402 -46.0765    2.5  54.8    7.7   0.6213   4.6 ------	UNKNOWN                       
  4.7220   1.2639    1.2  18.2  158.3   0.2992   9.4  293.3	UNKNOWN                       
  2.9551  33.5832    2.2  43.6 -158.4   0.2999   5.4 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
107.436590 495.436590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
326.1119  38.2641   10.8  51.2  165.0   1.1068   1.1    4.5	Cyg X-2                       
333.2171 -24.9891    2.2  40.2   71.2   5.7406   5.2 ------	UNKNOWN                       
341.9700 -40.3856    3.8  46.5   47.9   3.8518   3.1 ------	UNKNOWN                       
  6.4733 -46.8274    3.1  48.1   22.4   2.8331   3.7 ------	UNKNOWN                       
 12.8568 -21.4299    2.9  24.0    5.1   1.0949   3.9 ------	UNKNOWN                       
 40.0580  13.7204    2.9  37.1  -87.4   3.5061   4.0 ------	UNKNOWN