GRB180115A: 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 Feb  2 15:57:14 EST 2018
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger805318
======================================================================

  Trigger: 00805318      Segment: 000

  BAT Trigger Time: 537682584   [s; MET]
      Trigger Stop: 537682648   [s; MET]
               UTC: 2018-01-15T04:16:03.681260    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 12.0731321155951   Dec: -15.607820379834  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.76
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    7.76

  Analysis Position:   [ source = BAT ]
    RA: 12.0731321155951   Dec: -15.607820379834  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 12.0411370989957   Dec: -15.6309153967405  [deg; J2000]  
        { 00h 48m 09.9s , -15d 37' 51.3" }
         +/- 1.82636961627224 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.666851678109654 [arcmin] (formal 1-sigma fit error)
    SNR: 12.8653105791742
 
  Angular difference between the analysis and refined position is 2.310468 arcmin
 
  Partial Coding Fraction: 0.5703125    [ including projection effects ]

  Duration
     T90: 39.1440000534058 +/- 2.99202276282143
        Measured from: 27.7359999418259
                   to: 66.8799999952316     [s; relative to TRIGTIME]
     T50: 30.7239998579025 +/- 2.9044407717326
        Measured from: 33.6640000343323
                   to: 64.3879998922348     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 30.7519999742508     
                   to: 31.7519999742508     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 26.4919999837875     
                   to: 70.2519999742508     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.366802   0.509069   0.271206   0.080877
           0.048754   0.050951   0.044841   0.039628 [error]
 Peak      0.022419   0.026975   0.016515   0.010412
           0.007436   0.007575   0.006594   0.005809 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   43.760   26.492   70.252
T90    39.144   27.736   66.880
T50    30.724   33.664   64.388
Peak    1.000   30.752   31.752
 
 
====== 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      -1.676    -0.222      0.216       -           -               -         1.86e-03     -2.46e-04          2.41e-04      38.150   57
CPL     -1.679    -0.219      0.222     9999.340    -9999.330      -9999.340      1.86e-03     -1.12e-03          1.21e-03      38.160   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      -1.451     -0.628     0.660       -           -               -         4.68e-03     -1.54e-03          1.47e-03      45.020   57
CPL     -1.478     -0.929     1.049     9999.360      N/A           N/A         4.67e-03        N/A               N/A         45.030   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   1.23e-07  2.03e-07  2.54e-07  6.31e-07  7.56e-07  1.21e-06   erg/cm2
      90%_error_low -2.25e-08 -2.38e-08 -4.55e-08 -2.08e-07 -1.05e-07 -2.54e-07   erg/cm2
      90%_error_hi   2.33e-08  2.37e-08  4.56e-08  2.69e-07  1.07e-07  3.03e-07   erg/cm2
Peak flux       PL   1.84e-01  1.90e-01  1.39e-01  1.64e-01  5.77e-01  6.77e-01   ph/cm2/s
      90%_error_low -9.97e-02 -6.78e-02 -5.87e-02 -1.08e-01 -1.81e-01 -2.13e-01   ph/cm2/s
      90%_error_hi   1.12e-01  6.28e-02  5.64e-02  2.08e-01  1.81e-01  2.21e-01   ph/cm2/s
 
Fluence        CPL   1.24e-07  2.00e-07  2.53e-07  7.66e-07  7.68e-07  1.23e-06   erg/cm2
      90%_error_low    N/A       N/A       N/A    -5.43e-07 -1.00e-07 -4.56e-07   erg/cm2
      90%_error_hi     N/A       N/A       N/A     -1.48e-09  9.48e-08  1.19e-07   erg/cm2
Peak flux      CPL   1.59e-01  1.19e-01  6.15e-02  5.45e-02  3.62e-01  3.94e-01   ph/cm2/s
      90%_error_low     N/A   -1.19e-01 -6.15e-02 -5.45e-02 -3.62e-01 -3.94e-01   ph/cm2/s
      90%_error_hi      N/A    9.61e-02  3.45e-02  2.02e-02  2.39e-01  2.39e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
   12.0411   -15.6309   0.0151    27.1706   129.7090         1.3003228     12.865 TRIG_00805318                 
 
Foreground time interval of the image:
 26.492  70.252 (delta_t =  43.760 [sec])
Background time interval of the image:
-239.000  26.492 (delta_t = 265.492 [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   26.492 sec. to   70.252 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.67581     ( -0.222503   0.216082 )
Norm@50keV  : 1.86171E-03    ( -0.000246289   0.000240831 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          38.15 using 59 PHA bins.
# Reduced chi-squared =         0.6693 for     57 degrees of freedom 
# Null hypothesis probability =   9.741041e-01
 
Photon flux (15-150 keV)    in 43.76 sec: 0.245212 ( -0.028803  0.028822 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.55941e-07 ( -1.05126e-07  1.07032e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   26.492 sec. to   70.252 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.17498     ( -0.219217   0.221928 )
Epeak [keV] : 67.1008      ( -9999.35 -9999.36 )
Norm@50keV  : 9.99663E-04    ( -0.000257501   0.00206501 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          37.14 using 59 PHA bins.
# Reduced chi-squared =         0.6632 for     56 degrees of freedom 
# Null hypothesis probability =   9.755061e-01
 
Photon flux (15-150 keV)    in 43.76 sec: 0.246240 ( -0.033371  0.031542 ) ph/cm2/s
Energy fluence (15-150 keV)             : 7.67835e-07 ( -1.00141e-07  9.48205e-08 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   30.752 sec. to   31.752 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.45062     ( -0.628233   0.660115 )
Norm@50keV  : 4.68021E-03    ( -0.00153661   0.001473 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          45.02 using 59 PHA bins.
# Reduced chi-squared =         0.7898 for     57 degrees of freedom 
# Null hypothesis probability =   8.746242e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.576869 ( -0.180961  0.181271 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.47878e-08 ( -1.58684e-08  1.64571e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   30.752 sec. to   31.752 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.32047     ( -0.0869349   1.89113 )
Epeak [keV] : 112.899      (   )
Norm@50keV  : 1.61519E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          44.69 using 59 PHA bins.
# Reduced chi-squared =         0.7981 for     56 degrees of freedom 
# Null hypothesis probability =   8.612568e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.362052 ( -0.362052  0.239345 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.45872e-08 ( -1.58953e-08  1.612e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 39.144 sec.
Hardness ratio (energy fluence ratio) = 1.25198728179

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

S(15-50 keV)  = 3.252906e-07
S(50-150 keV) = 4.306483e-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 = -3.279303985073420E-01, IMY = -3.948671973416092E-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:
-239.000000 26.492000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
308.2272  40.9705   14.9  57.8  -19.0  -0.9239  -0.8    5.4	Cyg X-3                       
326.1733  38.3261  169.2  47.2   -7.3  -0.0290  -0.1    0.3	Cyg X-2                       
 31.0663 -33.7262    3.1  50.3  145.4   4.4743   3.7 ------	UNKNOWN                       
  8.5263  34.2240    3.5  44.3   40.9   1.9852   3.3 ------	UNKNOWN                       
 12.0725 -58.2973    2.4  56.9  179.0   6.9890   4.8 ------	UNKNOWN                       

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

Time interval of the image:
26.492000 70.252000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
308.0839  41.1176   12.3  58.0  -19.0   0.3313   0.9   10.0	Cyg X-3                       
326.1511  38.1768    3.9  47.1   -7.4   0.4052   2.9    8.7	Cyg X-2                       
 12.0411 -15.6309    0.9  27.2  129.7   1.3003  12.9 ------	UNKNOWN                       
349.1009  -8.9912    2.2   4.7  163.3   0.3643   5.1 ------	UNKNOWN                       
337.8263 -26.6844    2.6  23.3 -145.2   0.3383   4.5 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
120.300600 963.063300
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
  9.1666  18.2737    2.9  34.0   12.7   2.3765   4.1 ------	UNKNOWN                       
  7.0444   7.8145    3.0  23.9    5.3   1.7856   3.8 ------	UNKNOWN                       
 52.3585 -65.8613    3.4  56.9  179.2  12.8533   3.4 ------	UNKNOWN                       
340.1721  24.5630    4.1  50.8  -20.7   3.2007   2.8 ------	UNKNOWN                       
331.5894 -51.1205    3.0  48.0 -129.1  10.9133   3.9 ------	UNKNOWN