GRB080506: 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: Sat May  9 10:50:04 EDT 2015
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/batevent_reproc/trigger311159
======================================================================

  Trigger: 00311159      Segment: 000

  BAT Trigger Time: 231788784   [s; MET]
      Trigger Stop: 231788848   [s; MET]
               UTC: 2008-05-06T17:46:21.229360    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 329.434621981101   Dec: 39.002344120271  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.18
     Image Trigger?:     YES
     Rate S/N Ratio:     0  [ if not an image trigger ]
     Image S/N Ratio:    7.18

  Analysis Position:   [ source = BAT ]
    RA: 329.434621981101   Dec: 39.002344120271  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 329.468268910384   Dec: 38.9425027233463  [deg; J2000]  
        { 21h 57m 52.4s , +38d 56' 33.0" }
         +/- 2.51853198798169 [arcmin] (estimated 90% radius based on SNR)
         +/- 1.64418024243542 [arcmin] (formal 1-sigma fit error)
    SNR: 8.12925157751559
 
  Angular difference between the analysis and refined position is 3.918544 arcmin
 
  Partial Coding Fraction: 0.609375    [ including projection effects ]

  Duration
     T90: 152.199999988079 +/- 14.1792185809744
        Measured from: 31.6800000071526
                   to: 183.879999995232     [s; relative to TRIGTIME]
     T50: 103.260000020266 +/- 55.6425332669049
        Measured from: 57.891999989748
                   to: 161.152000010014     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 134.476000010967     
                   to: 135.476000010967     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: 19.0679999887943     
                   to: 188.819999992847     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.796603   0.815389   0.545655   0.272380
           0.073489   0.076898   0.069162   0.063980 [error]
 Peak      0.014923   0.018028   0.007202   0.009874
           0.004875   0.005140   0.004712   0.004291 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  169.752   19.068  188.820
T90   152.200   31.680  183.880
T50   103.260   57.892  161.152
Peak    1.000  134.476  135.476
 
 
====== 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      -1.754    -0.188      0.182       -           -               -         8.28e-04     -9.52e-05          9.32e-05      47.990   57
CPL     -1.758    -0.183      0.189     9999.360    -9999.350      -9999.360      8.27e-04     -4.73e-04          6.64e-04      48.000   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      -1.809     -0.782     0.655       -           -               -         2.48e-03     -1.15e-03          1.04e-03      39.030   57
CPL     -1.816     -0.978     2.462     9999.320      N/A           N/A         2.47e-03        N/A               N/A         39.030   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   2.28e-07  3.59e-07  4.26e-07  9.81e-07  1.30e-06  1.99e-06   erg/cm2
      90%_error_low -3.38e-08 -3.49e-08 -6.68e-08 -2.83e-07 -1.53e-07 -3.53e-07   erg/cm2
      90%_error_hi   3.48e-08  3.49e-08  6.74e-08  3.54e-07  1.56e-07  4.11e-07   erg/cm2
Peak flux       PL   1.37e-01  1.15e-01  6.58e-02  5.57e-02  3.43e-01  3.74e-01   ph/cm2/s
      90%_error_low -6.46e-02 -3.87e-02 -3.72e-02 -5.57e-02 -1.14e-01 -1.30e-01   ph/cm2/s
      90%_error_hi   6.87e-02  3.84e-02  3.90e-02  9.16e-02  1.14e-01  1.36e-01   ph/cm2/s
 
Fluence        CPL   2.29e-07  3.58e-07  4.26e-07  9.97e-07  1.30e-06  2.04e-06   erg/cm2
      90%_error_low    N/A    -3.37e-08    N/A       N/A    -1.95e-07 -8.11e-07   erg/cm2
      90%_error_hi     N/A     4.59e-08    N/A       N/A     1.26e-07  1.88e-07   erg/cm2
Peak flux      CPL   1.40e-01  1.14e-01  6.43e-02  5.13e-02  3.45e-01  3.76e-01   ph/cm2/s
      90%_error_low -6.72e-02 -1.14e-01 -3.59e-02 -3.12e-02 -1.17e-01 -1.40e-01   ph/cm2/s
      90%_error_hi   6.81e-02  3.96e-02  4.07e-02  9.87e-02  1.11e-01  1.24e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  329.4683    38.9425   0.0238    37.5577   -19.3829         0.8498448      8.129 TRIG_00311159                 
 
Foreground time interval of the image:
 19.068  73.301 (delta_t =  54.233 [sec])
Background time interval of the image:
-134.699  19.068 (delta_t = 153.767 [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   19.068 sec. to  188.820 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.75394     ( -0.187789   0.182115 )
Norm@50keV  : 8.28453E-04    ( -9.52265e-05   9.32488e-05 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          47.99 using 59 PHA bins.
# Reduced chi-squared =         0.8420 for     57 degrees of freedom 
# Null hypothesis probability =   7.964764e-01
 
Photon flux (15-150 keV)    in 169.8 sec: 0.112189 ( -0.010957  0.010962 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.29792e-06 ( -1.53177e-07  1.56125e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   19.068 sec. to  188.820 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.75838     ( -0.185292   0.186744 )
Epeak [keV] : 9999.36      ( -9999.35 -9999.36 )
Norm@50keV  : 8.27057E-04    ( -0.00047421   0.000662309 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          48.00 using 59 PHA bins.
# Reduced chi-squared =         0.8571 for     56 degrees of freedom 
# Null hypothesis probability =   7.677883e-01
 
Photon flux (15-150 keV)    in 169.8 sec: 0.112322 ( -0.01133  0.010925 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.30454e-06 ( -1.95346e-07  1.25794e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from  134.476 sec. to  135.476 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.80886     ( -0.781919   0.654681 )
Norm@50keV  : 2.47943E-03    ( -0.00114964   0.00103648 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          39.03 using 59 PHA bins.
# Reduced chi-squared =         0.6847 for     57 degrees of freedom 
# Null hypothesis probability =   9.669598e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.342858 ( -0.114237  0.114298 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.28223e-08 ( -9.72355e-09  1.06403e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  134.476 sec. to  135.476 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.59923     ( -0.194113   3.24611 )
Epeak [keV] : 197.577      (   )
Norm@50keV  : 9.50716E-04    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          38.43 using 59 PHA bins.
# Reduced chi-squared =         0.6863 for     56 degrees of freedom 
# Null hypothesis probability =   9.648113e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.345247 ( -0.117001  0.11078 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.78242e-08 ( -1.12637e-08  9.66677e-09 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 152.2 sec.
Hardness ratio (energy fluence ratio) = 1.18598747649

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

S(15-50 keV)  = 5.871543e-07
S(50-150 keV) = 7.107677e-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 = 7.253459036448802E-01, IMY = 2.551906428780563E-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:
-134.699400 19.068000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.5357  35.3556    6.6  37.8   85.7   0.7962   1.8    3.9	Her X-1                       
299.5909  35.2016    0.4  34.3   21.8   5.2225  28.4    0.0	Cyg X-1                       
308.1012  40.9598    4.0  30.0    7.2   0.4592   2.9    0.6	Cyg X-3                       
326.1496  38.3203   93.4  37.1  -15.1   0.0238   0.1    1.0	Cyg X-2                       
196.9199  42.0037    3.2  51.3  148.6   2.4599   3.7 ------	UNKNOWN                       
200.3035  47.9683    2.2  45.0  149.7   1.9320   5.1 ------	UNKNOWN                       
345.3588  24.2441    2.8  56.3  -28.7   3.3018   4.2 ------	UNKNOWN                       

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

Time interval of the image:
19.068000 73.300590
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.4685  35.4021    6.1  37.8   85.8  -0.5559  -1.9    3.6	Her X-1                       
299.4850  35.1010   21.1  34.4   22.0  -0.0620  -0.5    7.9	Cyg X-1                       
307.9951  40.8275    7.1  30.1    7.5  -0.1579  -1.6    9.1	Cyg X-3                       
326.1352  38.1658    5.9  37.2  -14.9   0.2190   1.9    9.5	Cyg X-2                       
317.1369  17.5014    2.3  54.7    4.4   1.8245   4.9 ------	UNKNOWN                       
329.4684  38.9425    1.4  37.6  -19.4   0.8501   8.1 ------	UNKNOWN                       
344.6690  25.2718    2.0  55.1  -28.4   2.1605   5.9 ------	UNKNOWN                       
  1.2886  47.0889    2.0  41.6  -57.7   1.1717   5.9 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
129.300600 543.105500
841.000000 903.053700
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.5910  35.1975    0.3  24.0   94.5  17.6210  44.5    0.2	Cyg X-1                       
308.1175  40.9075    2.6  16.4  107.7   1.3751   4.5    2.7	Cyg X-3                       
326.3671  38.1876   76.6   2.5   76.6   0.0496   0.2   12.2	Cyg X-2                       
260.4367  53.8677    2.5  47.7  136.2   6.1531   4.6 ------	UNKNOWN                       
307.6600  62.2980    2.6  26.8  161.7   1.6027   4.4 ------	UNKNOWN                       
329.4581  39.0433    2.1   0.1 -155.6   1.8660   5.3 ------	UNKNOWN                       
  3.8828  40.5261    5.1  26.4 -100.2   0.9469   2.3 ------	UNKNOWN                       
 38.7971  66.0090    3.5  46.7 -144.2   2.1990   3.3 ------	UNKNOWN