GRB080810: 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 Jan 19 23:21:37 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger319584
======================================================================

  Trigger: 00319584      Segment: 000

  BAT Trigger Time: 240066615.296   [s; MET]
      Trigger Stop: 240066616.32   [s; MET]
               UTC: 2008-08-10T13:10:12.287980    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 356.779571156542   Dec: 0.319715625427062  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.59
     Image Trigger?:     NO
     Rate S/N Ratio:     14.7309198626562  [ if not an image trigger ]
     Image S/N Ratio:    7.59

  Analysis Position:   [ source = BAT ]
    RA: 356.779571156542   Dec: 0.319715625427062  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 356.78300404361   Dec: 0.312256406462367  [deg; J2000]  
        { 23h 47m 07.9s , +00d 18' 44.1" }
         +/- 1.1690293015403 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.594737582105186 [arcmin] (formal 1-sigma fit error)
    SNR: 24.3346416899719
 
  Angular difference between the analysis and refined position is 0.492674 arcmin
 
  Partial Coding Fraction: 0.6875    [ including projection effects ]

  Duration
     T90: 107.668000012636 +/- 3.47154376061863
        Measured from: -6.22400000691414
                   to: 101.444000005722     [s; relative to TRIGTIME]
     T50: 38.9480000138283 +/- 2.52967428011403
        Measured from: 10.447999984026
                   to: 49.3959999978542     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 24.6800000071526     
                   to: 25.6800000071526     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -20.4959999918938     
                   to: 106.491999983788     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.844654   2.445282   2.153071   0.800968
           0.065791   0.069537   0.063197   0.058147 [error]
 Peak      0.063743   0.087361   0.076435   0.027669
           0.006959   0.007607   0.007309   0.006267 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  126.988  -20.496  106.492
T90   107.668   -6.224  101.444
T50    38.948   10.448   49.396
Peak    1.000   24.680   25.680
 
 
====== 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      -1.270    -0.065      0.065       -           -               -         3.67e-03     -1.16e-04          1.16e-04      61.170   57
CPL     -1.265    -0.067      0.064     9999.350    -9999.350      -9999.350      3.69e-03     -1.16e-04          4.33e-04      61.380   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      -1.236     -0.170     0.170       -           -               -         1.68e-02     -1.51e-03          1.51e-03      60.020   57
CPL     -1.230     -0.174     0.271     9999.360    -9999.360      -9999.360      1.69e-02     -1.34e-02          -9.97e-03      60.040   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   4.80e-07  1.02e-06  1.68e-06  6.34e-06  4.64e-06  9.52e-06   erg/cm2
      90%_error_low -3.32e-08 -3.95e-08 -6.50e-08 -5.81e-07 -1.60e-07 -6.11e-07   erg/cm2
      90%_error_hi   3.41e-08  3.93e-08  6.48e-08  6.24e-07  1.61e-07  6.47e-07   erg/cm2
Peak flux       PL   5.37e-01  6.32e-01  5.37e-01  7.73e-01  1.98e+00  2.48e+00   ph/cm2/s
      90%_error_low -9.11e-02 -6.48e-02 -6.10e-02 -1.76e-01 -1.79e-01 -2.41e-01   ph/cm2/s
      90%_error_hi   9.59e-02  6.38e-02  6.01e-02  2.07e-01  1.80e-01  2.48e-01   ph/cm2/s
 
Fluence        CPL   4.80e-07  1.01e-06  1.66e-06  6.40e-06  4.68e-06  9.08e-06   erg/cm2
      90%_error_low -3.32e-08 -3.39e-08 -4.30e-08 -1.11e-06 -2.01e-07 -2.24e-07   erg/cm2
      90%_error_hi   3.41e-08  4.50e-08  8.71e-08  7.92e-07  1.21e-07  1.01e-06   erg/cm2
Peak flux      CPL   5.37e-01  6.32e-01  5.37e-01  8.40e-01  1.98e+00  2.49e+00   ph/cm2/s
      90%_error_low     N/A   -6.48e-02 -6.09e-02     N/A   -1.79e-01 -3.31e-01   ph/cm2/s
      90%_error_hi      N/A    6.52e-02  6.03e-02     N/A    1.79e-01  2.16e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  356.7830     0.3123   0.0079    20.4484    63.9740         1.9488337     24.335 TRIG_00319584                 
 
Foreground time interval of the image:
-20.496  12.005 (delta_t =  32.501 [sec])
Background time interval of the image:
-239.296 -20.496 (delta_t = 218.800 [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  -20.496 sec. to  106.492 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.27     ( -0.0647763   0.0650173 )
Norm@50keV  : 3.66994E-03    ( -0.000115863   0.000115819 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.17 using 59 PHA bins.
# Reduced chi-squared =          1.073 for     57 degrees of freedom 
# Null hypothesis probability =   3.286188e-01
 
Photon flux (15-150 keV)    in 127 sec: 0.435510 ( -0.014836  0.014921 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.64091e-06 ( -1.60439e-07  1.60997e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -20.496 sec. to  106.492 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.26481     ( -0.0663852   0.0642971 )
Epeak [keV] : 9999.35      ( -9999.36 -9999.36 )
Norm@50keV  : 3.68524E-03    ( -0.000115857   0.000433316 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          61.38 using 59 PHA bins.
# Reduced chi-squared =          1.096 for     56 degrees of freedom 
# Null hypothesis probability =   2.892792e-01
 
Photon flux (15-150 keV)    in 127 sec: 0.435387 ( -0.01486  0.014899 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.67933e-06 ( -2.00919e-07  1.20589e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   24.680 sec. to   25.680 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.23648     ( -0.169763   0.170409 )
Norm@50keV  : 1.67943E-02    ( -0.00151453   0.00151155 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          60.02 using 59 PHA bins.
# Reduced chi-squared =          1.053 for     57 degrees of freedom 
# Null hypothesis probability =   3.669285e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.98204 ( -0.17926  0.17952 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.68702e-07 ( -1.77566e-08  1.79875e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   24.680 sec. to   25.680 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.10816     ( -0.173403   0.271026 )
Epeak [keV] : 39.6177      ( -9999.36 -9999.36 )
Norm@50keV  : 5.23895E-03    ( -0.00184635   0.00158911 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.97 using 59 PHA bins.
# Reduced chi-squared =          1.053 for     56 degrees of freedom 
# Null hypothesis probability =   3.676036e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.98162 ( -0.17932  0.17944 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.08177e-08 ( -1.8745e-08  1.68249e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 107.668 sec.
Hardness ratio (energy fluence ratio) = 1.65867067648

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

S(15-50 keV)  = 1.4954565e-06
S(50-150 keV) = 3.14544e-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 = 1.636026670224270E-01, IMY = -3.350496201258050E-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:
-239.296000 -20.496000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
308.0956  40.9530    7.6  49.6  177.2   0.7097   1.5    0.7	Cyg X-3                       
326.1064  38.2214    4.2  35.5  178.3   0.6165   2.7    6.8	Cyg X-2                       
298.3003  41.6244    2.7  57.0  177.3   4.9412   4.3 ------	UNKNOWN                       
299.7602  56.0420    3.2  57.7 -165.5   3.1562   3.6 ------	UNKNOWN                       
 40.0868  37.7223    2.6  37.6  -76.1   2.2549   4.5 ------	UNKNOWN                       
 47.4341  33.8875    2.7  42.7  -68.4   3.8220   4.3 ------	UNKNOWN                       
 35.6286  51.6138    4.5  41.1  -98.0   2.6470   2.7 ------	UNKNOWN                       
 35.5568  51.9695    5.3  41.3  -98.5   2.5599   2.7 ------	UNKNOWN                       

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

Time interval of the image:
-20.496000 12.004600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
308.0741  41.0581    7.4  49.6  177.4   0.2529   1.6    6.5	Cyg X-3                       
326.2455  38.3776    3.6  35.5  178.7   0.2829   3.2    4.8	Cyg X-2                       
356.7830   0.3122    0.5  20.4   64.0   1.9491  24.3  193.9	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
64.004600 482.834000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
326.1689  38.3152  100.2  47.3  172.6   0.4311   0.1    0.4	Cyg X-2                       
319.9531  24.1376    2.3  42.9  152.1  17.9640   5.1 ------	UNKNOWN                       
  0.1368 -31.7760    2.6  32.2   20.2   7.6153   4.4 ------	UNKNOWN                       
353.8194 -21.6099    3.0  22.1   32.9   5.7089   3.9 ------	UNKNOWN                       
340.1769  54.5879    2.9  56.0 -166.0  20.8807   4.0 ------	UNKNOWN                       
 35.4886  15.1323    3.0  41.0  -87.5  21.4450   3.9 ------	UNKNOWN