GRB080524

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 GROUND-DETECTED GRB DATA PROCESSING REPORT                 
    Process Script: hand-made scripts that follow steps in batgrbproduct
                    but without using TDRSS info
    Process Start Time: Tue Sep 30 00:02:25 EDT 2014
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/ground_detect_bursts/scripts
==========================================================================
 
  BAT Trigger Time: 233295182.4
               UTC: 2008-05-24T04:12:59.587   [includes UTCF correction]
       Where From?: Ground analysis (best_duration.txt)
  NOTE: BAT trigger time for ground-detected burst is the T100 start time.
 
  Refined Position:   [ source = BAT pre-slew image ]
    RA: 268.517430044   Dec: 80.1371445641  [deg; J2000]
        { 17h 54m 04.2s , +80d 08' 13.7" }
        +/- 2.44321909466 [arcmin] (estimated 90% radius based on SNR)
    SNR: 8.49069377304
 
 
  Angular difference between the analysis and refined position is Usage: arcmin
 
  Partial Coding Fraction: 5.000000e-01    [ including projection effects ]
 
  Duration
     T90: 6.40000000596046 +/- 1.6
        Measured from: 0
                   to: 6.4     [s; relative to TRIGTIME]
     T50: 3.20000001788139 +/- 1.6
        Measured from: 1.6
                   to: 4.8     [s; relative to TRIGTIME]
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    6.400    0.000    6.400
T90     6.400    0.000    6.400
T50     3.200    1.600    4.800
Peak    1.000    1.900    2.900
 
 
====== 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      -0.898    -0.324      0.355       -           -               -         3.46e-03     -6.86e-04          6.69e-04      37.660   57
CPL     -0.568    -0.623      1.586      257.085    -257.085      -257.085      4.80e-03     -1.94e-03          1.66e-02      37.460   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      -1.152     -0.564     0.626       -           -               -         4.98e-03     -1.67e-03          1.67e-03      57.910   57
CPL     -0.640     -7.989     2.118      136.592    -136.592      -136.592      8.95e-03        N/A               N/A         57.710   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   1.61e-08  4.30e-08  9.22e-08  5.14e-07  2.49e-07  6.65e-07   erg/cm2
      90%_error_low -6.23e-09 -1.09e-08 -1.77e-08 -1.97e-07 -4.72e-08 -2.07e-07   erg/cm2
      90%_error_hi   7.28e-09  1.06e-08  1.75e-08  2.81e-07  4.74e-08  2.80e-07   erg/cm2
Peak flux       PL   1.47e-01  1.82e-01  1.64e-01  2.56e-01  5.81e-01  7.49e-01   ph/cm2/s
      90%_error_low -8.52e-02 -7.56e-02 -6.10e-02 -1.52e-01 -2.01e-01 -2.52e-01   ph/cm2/s
      90%_error_hi   1.06e-01  7.27e-02  5.98e-02  2.63e-01  2.03e-01  2.70e-01   ph/cm2/s
 
Fluence        CPL   1.47e-08  4.37e-08  9.57e-08  3.39e-07  2.45e-07  4.93e-07   erg/cm2
      90%_error_low -7.54e-09 -1.14e-08 -2.03e-08 -2.57e-07 -5.10e-08 -2.59e-07   erg/cm2
      90%_error_hi   8.32e-09  1.18e-08  2.22e-08  3.56e-07  4.88e-08  3.36e-07   erg/cm2
Peak flux      CPL   1.34e-01  1.91e-01  1.72e-01  1.44e-01  5.71e-01  6.40e-01   ph/cm2/s
      90%_error_low -9.23e-02 -8.22e-02 -3.71e-02 -1.44e-01 -2.02e-01 -2.61e-01   ph/cm2/s
      90%_error_hi   1.14e-01  9.38e-02  7.15e-02  1.74e-01  2.07e-01  3.60e-01   ph/cm2/s
 
======================================================================

Special notes of this burst

Image

15.0-350.0 keV image (Event data)

#RAcent DECcent POSerr Theta  Phi  Peak_Cts  SNR Name
268.517 80.137 0.022 41.494 -18.433 0.425 8.491 TRIG_00312277
 
Image time interval: -2.400 to 7.704 [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.

Best duration plot

Full-time range; 1 s binning

Bokeh Plot

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    0.000 sec. to    6.400 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.897674     ( -0.324156   0.354728 )
Norm@50keV  : 3.45723E-03    ( -0.000685694   0.00066892 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          37.66 using 59 PHA bins.
# Reduced chi-squared =         0.6607 for     57 degrees of freedom 
# Null hypothesis probability =   9.775304e-01
 
Photon flux (15-150 keV)    in 6.4 sec: 0.396802 ( -0.077354  0.078226 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.48565e-07 ( -4.71788e-08  4.74269e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    0.000 sec. to    6.400 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.567929     ( -0.623423   1.58537 )
Epeak [keV] : 257.085      ( -257.184 -257.184 )
Norm@50keV  : 4.79529E-03    ( -0.00194084   0.0166458 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          37.46 using 59 PHA bins.
# Reduced chi-squared =         0.6689 for     56 degrees of freedom 
# Null hypothesis probability =   9.731465e-01
 
Photon flux (15-150 keV)    in 6.4 sec: 0.391368 ( -0.079572  0.080557 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.44963e-07 ( -5.1017e-08  4.87551e-08 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from    1.900 sec. to    2.900 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.152     ( -0.564083   0.6256 )
Norm@50keV  : 4.98253E-03    ( -0.00167336   0.00166525 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.91 using 59 PHA bins.
# Reduced chi-squared =          1.016 for     57 degrees of freedom 
# Null hypothesis probability =   4.414658e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.581208 ( -0.200776  0.20318 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.12661e-08 ( -1.8156e-08  1.8562e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    1.900 sec. to    2.900 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.639791     ( -7.9888   2.11907 )
Epeak [keV] : 136.592      ( -136.662 -136.662 )
Norm@50keV  : 8.95392E-03    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.71 using 59 PHA bins.
# Reduced chi-squared =          1.030 for     56 degrees of freedom 
# Null hypothesis probability =   4.119009e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.570641 ( -0.201967  0.206682 ) ph/cm2/s
Energy fluence (15-150 keV)             : 4.92527e-08 ( -2.12468e-08  1.98556e-08 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 6.4 sec.
Hardness ratio (energy fluence ratio) = 2.14698966233

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

S(15-50 keV)  = 5.907519e-08
S(50-150 keV) = 1.8949146e-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 = 0.839154243097, IMY = 0.279685046939

Spacecraft aspect plot

Bright source in the event data image

Event data image of 15-350 keV band

Time interval of the image:
-2.400000 7.703800
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
214.4896  70.0161    2.6  28.8   -0.6   0.1599   4.5 ------	UNKNOWN                       
134.4576  19.1232    2.3  40.6 -164.8   0.2052   5.0 ------	UNKNOWN                       
268.5176  80.1371    1.4  41.5  -18.4   0.4247   8.5 ------	UNKNOWN                       
318.0468  68.8613    2.7  57.8  -21.7   0.7443   4.3 ------	UNKNOWN                       
 75.0291  68.0752    2.7  43.4  -65.9   0.5324   4.3 ------	UNKNOWN

Webpage updated on:
Sun Jun 21 01:18:00 EDT 2015

Analysis Summary

Notes:

Image

15.0-350.0 keV image (Event data)

Light Curves

Best duration plot

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:

Time averaged spectrum fit using the average DRM

Power-law model

Cutoff power-law model

1-s peak spectrum fit

Power-law model

Cutoff power-law model

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

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

Mask shadow pattern

Spacecraft aspect plot

Bright source in the event data image

Event data image of 15-350 keV band

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