GRB080727C: 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 23:42:13 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger318170
======================================================================

  Trigger: 00318170      Segment: 000

  BAT Trigger Time: 238892858.368   [s; MET]
      Trigger Stop: 238892859.392   [s; MET]
               UTC: 2008-07-27T23:07:35.394100    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 32.6448768441636   Dec: 64.1515714708512  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    7.95
     Image Trigger?:     NO
     Rate S/N Ratio:     13.3416640641263  [ if not an image trigger ]
     Image S/N Ratio:    7.95

  Analysis Position:   [ source = BAT ]
    RA: 32.6448768441636   Dec: 64.1515714708512  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 32.639747754007   Dec: 64.1300985461938  [deg; J2000]  
        { 02h 10m 33.5s , +64d 07' 48.4" }
         +/- 0.769389733470983 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.292686512664784 [arcmin] (formal 1-sigma fit error)
    SNR: 44.2350373901105
 
  Angular difference between the analysis and refined position is 1.295349 arcmin
 
  Partial Coding Fraction: 0.7734375    [ including projection effects ]

  Duration
     T90: 77.363999992609 +/- 7.03936359051065
        Measured from: 1.68000000715256
                   to: 79.0439999997616     [s; relative to TRIGTIME]
     T50: 23.3200000226498 +/- 1.43458984090877
        Measured from: 14.9799999892712
                   to: 38.3000000119209     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 15.2319999933243     
                   to: 16.2319999933243     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -3.30000001192093     
                   to: 110.247999995947     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     1.650692   2.958452   2.611177   0.606654
           0.057142   0.061597   0.056963   0.050429 [error]
 Peak      0.057938   0.103691   0.110149   0.022878
           0.006335   0.007377   0.007079   0.005600 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100  113.548   -3.300  110.248
T90    77.364    1.680   79.044
T50    23.320   14.980   38.300
Peak    1.000   15.232   16.232
 
 
====== 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: CPL)
 
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      -1.221    -0.047      0.047       -           -               -         4.74e-03     -1.21e-04          1.21e-04      68.620   57
CPL     -0.864    -0.188      0.197      178.906     -43.874       129.495      6.85e-03     -1.18e-03          1.49e-03      57.750   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      -1.050     -0.120     0.122       -           -               -         1.99e-02     -1.44e-03          1.44e-03      77.440   57
CPL     -0.251     -0.513     0.587      121.347     -29.721       112.133      4.64e-02     -1.91e-02          3.76e-02      69.910   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   5.29e-07  1.15e-06  1.98e-06  7.85e-06  5.43e-06  1.15e-05   erg/cm2
      90%_error_low -2.78e-08 -3.56e-08 -5.84e-08 -5.29e-07 -1.48e-07 -5.58e-07   erg/cm2
      90%_error_hi   2.84e-08  3.55e-08  5.83e-08  5.56e-07  1.48e-07  5.81e-07   erg/cm2
Peak flux       PL   5.32e-01  7.01e-01  6.77e-01  1.17e+00  2.30e+00  3.08e+00   ph/cm2/s
      90%_error_low -7.26e-02 -6.08e-02 -5.52e-02 -1.88e-01 -1.69e-01 -2.45e-01   ph/cm2/s
      90%_error_hi   7.60e-02  6.03e-02  5.49e-02  2.09e-01  1.69e-01  2.50e-01   ph/cm2/s
 
Fluence        CPL   4.84e-07  1.18e-06  2.04e-06  4.93e-06  5.30e-06  8.64e-06   erg/cm2
      90%_error_low -3.55e-08 -3.85e-08 -6.72e-08 -1.00e-06 -1.63e-07 -1.01e-06   erg/cm2
      90%_error_hi   3.61e-08  3.87e-08  6.77e-08  1.32e-06  1.63e-07  1.31e-06   erg/cm2
Peak flux      CPL   4.41e-01  7.39e-01  7.39e-01  5.60e-01  2.23e+00  2.48e+00   ph/cm2/s
      90%_error_low -8.99e-02 -6.91e-02 -6.82e-02 -1.95e-01 -1.75e-01 -2.65e-01   ph/cm2/s
      90%_error_hi   9.34e-02  7.01e-02  6.96e-02  3.20e-01  1.75e-01  3.49e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
   32.6397    64.1301   0.0044    20.2392   -64.6463         2.7711897     44.235 TRIG_00318170                 
 
Foreground time interval of the image:
 -3.300  18.533 (delta_t =  21.833 [sec])
Background time interval of the image:
-239.368  -3.300 (delta_t = 236.068 [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   -3.300 sec. to  110.248 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.22108     ( -0.0471193   0.0473229 )
Norm@50keV  : 4.74126E-03    ( -0.000120603   0.000120567 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          68.62 using 59 PHA bins.
# Reduced chi-squared =          1.204 for     57 degrees of freedom 
# Null hypothesis probability =   1.392519e-01
 
Photon flux (15-150 keV)    in 113.5 sec: 0.558237 ( -0.015126  0.015154 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.42821e-06 ( -1.47817e-07  1.4822e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   -3.300 sec. to  110.248 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.864335     ( -0.188406   0.197146 )
Epeak [keV] : 178.906      ( -43.8744 129.495 )
Norm@50keV  : 6.85075E-03    ( -0.00117952   0.00149286 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.75 using 59 PHA bins.
# Reduced chi-squared =          1.031 for     56 degrees of freedom 
# Null hypothesis probability =   4.104455e-01
 
Photon flux (15-150 keV)    in 113.5 sec: 0.545702 ( -0.016364  0.016392 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.30232e-06 ( -1.63237e-07  1.62749e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from   15.232 sec. to   16.232 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.04968     ( -0.120358   0.121956 )
Norm@50keV  : 1.98789E-02    ( -0.00144378   0.00144335 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          77.44 using 59 PHA bins.
# Reduced chi-squared =          1.359 for     57 degrees of freedom 
# Null hypothesis probability =   3.717234e-02
 
Photon flux (15-150 keV)    in 1 sec: 2.29589 ( -0.16929  0.16943 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.1132e-07 ( -1.70168e-08  1.71294e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from   15.232 sec. to   16.232 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.251374     ( -0.513449   0.587278 )
Epeak [keV] : 121.347      ( -29.7206 112.134 )
Norm@50keV  : 4.64149E-02    ( -0.0190896   0.0376419 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          69.91 using 59 PHA bins.
# Reduced chi-squared =          1.248 for     56 degrees of freedom 
# Null hypothesis probability =   1.001374e-01
 
Photon flux (15-150 keV)    in 1 sec: 2.23144 ( -0.17494  0.17471 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.77251e-08 ( -1.4564e-08  8.01952e-09 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 77.364 sec.
Hardness ratio (energy fluence ratio) = 1.73508220055

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

S(15-50 keV)  = 1.661286e-06
S(50-150 keV) = 3.641032e-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 = 1.578814225197023E-01, IMY = 3.331922850841051E-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:
-239.368000 -3.300000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.5857  35.1879    0.7  40.7  135.9   8.7618  17.4    0.9	Cyg X-1                       
308.1612  40.9372    4.2  32.0  133.4   0.8160   2.8    2.5	Cyg X-3                       
326.0996  38.2689    3.9  26.0  106.9   0.8061   2.9    4.6	Cyg X-2                       
285.6341  33.0528    2.3  49.6  146.9   4.3002   4.9 ------	UNKNOWN                       
323.3445  31.6332    2.4  32.9  104.6   1.7250   4.9 ------	UNKNOWN                       
106.4056  73.0572    4.3  41.1  -98.2   3.1772   2.7 ------	UNKNOWN                       

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

Time interval of the image:
-3.300000 18.532610
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.4654  35.0703    4.4  40.9  135.9   0.3782   2.6   10.0	Cyg X-1                       
308.3157  40.8133   11.3  32.0  133.1  -0.0909  -1.0   12.5	Cyg X-3                       
326.3772  38.4336    0.0  25.7  106.6  -0.1144  -1.5   11.8	Cyg X-2                       
 37.4393  41.9851    3.0  33.2  -22.3   0.2569   3.8 ------	UNKNOWN                       
 32.6397  64.1301    0.3  20.2  -64.6   2.7713  44.2 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image:
61.532600 362.774100
420.632000 482.693600
600.632000 662.724100
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
270.1649  59.0226    3.4  49.4  158.2   2.8548   3.4 ------	UNKNOWN                       
 32.7203  64.1684    1.9   0.0 -105.4   1.5542   6.0 ------	UNKNOWN                       
 39.2630  44.4543    1.9  20.0   -0.8   1.3837   6.0 ------	UNKNOWN                       
 74.7641  19.5421    3.1  52.7  -39.5   4.3553   3.7 ------	UNKNOWN