GRB050505: 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: Wed Jan 22 22:08:33 EST 2014
             Host Name: batevent1
   Current Working Dir: /local/data/batevent/batevent_reproc/trigger117504
======================================================================

  Trigger: 00117504      Segment: 000

  BAT Trigger Time: 137028140.608   [s; MET]
      Trigger Stop: 137028142.656   [s; MET]
               UTC: 2005-05-05T23:22:21.098760    [includes UTCF correction] 
       Where From?: TDRSS position message

  BAT 
    RA: 141.781927347682   Dec: 30.2552283992829  [deg; J2000]

     Catalogged Source?: NO
     Point Source?:      YES
     GRB Indicated?:     YES    [ by BAT flight software ]
     Image S/N Ratio:    10
     Image Trigger?:     NO
     Rate S/N Ratio:     15.4596248337403  [ if not an image trigger ]
     Image S/N Ratio:    10

  Analysis Position:   [ source = BAT ]
    RA: 141.781927347682   Dec: 30.2552283992829  [deg; J2000]

  Refined Position:   [ source = BAT pre-slew burst ]
    RA: 141.757260913215   Dec: 30.2668789959081  [deg; J2000]  
        { 09h 27m 01.7s , +30d 16' 00.8" }
         +/- 1.30574510164845 [arcmin] (estimated 90% radius based on SNR)
         +/- 0.371102249786264 [arcmin] (formal 1-sigma fit error)
    SNR: 20.7781258503818
 
  Angular difference between the analysis and refined position is 1.456968 arcmin
 
  Partial Coding Fraction: 0.2480469    [ including projection effects ]

  Duration
     T90: 58.852000027895 +/- 6.83979532780525
        Measured from: -8.64400002360344
                   to: 50.2080000042915     [s; relative to TRIGTIME]
     T50: 26.9120000004768 +/- 5.93884163816196
        Measured from: -0.763999998569489
                   to: 26.1480000019073     [s; relative to TRIGTIME]



  Fluence
     Peak Flux  (peak 1 second)
        Measured from: 1.01999998092651     
                   to: 2.01999998092651     [s; relative to TRIGTIME]
     Total Fluence        
        Measured from: -10.0640000104904     
                   to: 52.5079999864101     [s; relative to TRIGTIME]
     
             Band 1     Band 2     Band 3     Band 4
              15-25      25-50     50-100    100-350     keV
 Total     0.691584   1.323308   1.069492   0.337626
           0.080931   0.084672   0.073827   0.060864 [error]
 Peak      0.021365   0.082422   0.083801   0.030057
           0.010418   0.011807   0.010660   0.008530 [error]

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

======================================================================
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100   62.572  -10.064   52.508
T90    58.852   -8.644   50.208
T50    26.912   -0.764   26.148
Peak    1.000    1.020    2.020
 
 
====== 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      -1.395    -0.118      0.119       -           -               -         4.12e-03     -2.88e-04          2.88e-04      42.840   57
CPL     -0.968    -0.465      0.533      131.948     -45.516      -131.948      6.55e-03     -2.52e-03          4.92e-03      40.510   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      -1.083     -0.241     0.257       -           -               -         1.59e-02     -2.53e-03          2.49e-03      62.810   57
CPL     -0.318     -0.862     1.183      132.810     -47.987      -132.810      3.36e-02     -1.90e-02          6.44e-02      60.900   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   2.99e-07  5.85e-07  8.89e-07  2.94e-06  2.49e-06  4.71e-06   erg/cm2
      90%_error_low -3.92e-08 -4.79e-08 -7.14e-08 -4.85e-07 -1.81e-07 -5.34e-07   erg/cm2
      90%_error_hi   4.09e-08  4.75e-08  7.10e-08  5.46e-07  1.81e-07  5.80e-07   erg/cm2
Peak flux       PL   4.38e-01  5.66e-01  5.34e-01  8.91e-01  1.84e+00  2.43e+00   ph/cm2/s
      90%_error_low -1.33e-01 -1.16e-01 -8.14e-02 -2.48e-01 -3.04e-01 -3.64e-01   ph/cm2/s
      90%_error_hi   1.49e-01  1.15e-01  8.11e-02  3.02e-01  3.08e-01  3.66e-01   ph/cm2/s
 
Fluence        CPL   2.73e-07  6.07e-07  9.29e-07  1.72e-06  2.45e-06  3.52e-06   erg/cm2
      90%_error_low -4.77e-08 -5.44e-08 -8.42e-08 -7.30e-07 -1.91e-07 -7.38e-07   erg/cm2
      90%_error_hi   4.93e-08  5.57e-08  8.57e-08  1.36e-06  1.90e-07  1.89e-06   erg/cm2
Peak flux      CPL   3.52e-01  5.83e-01  5.92e-01  4.98e-01  1.79e+00  2.02e+00   ph/cm2/s
      90%_error_low -1.55e-01 -1.29e-01 -1.07e-01 -2.47e-01 -3.07e-01 -4.09e-01   ph/cm2/s
      90%_error_hi   1.79e-01  1.29e-01  1.11e-01  5.15e-01  3.12e-01  5.94e-01   ph/cm2/s
 
======================================================================

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
  141.7573    30.2669   0.0093    49.3359  -157.1464         3.6471222     20.778 TRIG_00117504                 
 
Foreground time interval of the image:
-10.064  52.508 (delta_t =  62.572 [sec])
Background time interval of the image:
-299.608 -10.064 (delta_t = 289.544 [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  -10.064 sec. to   52.508 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.3954     ( -0.117582   0.118879 )
Norm@50keV  : 4.12095E-03    ( -0.000288181   0.000288095 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          42.84 using 59 PHA bins.
# Reduced chi-squared =         0.7516 for     57 degrees of freedom 
# Null hypothesis probability =   9.179366e-01
 
Photon flux (15-150 keV)    in 62.57 sec: 0.501342 ( -0.038179  0.038332 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.49417e-06 ( -1.8069e-07  1.81151e-07 ) ergs/cm2
 

Cutoff power-law model

Time interval is from  -10.064 sec. to   52.508 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.96813     ( -0.464942   0.533439 )
Epeak [keV] : 131.948      ( -45.5184 -131.951 )
Norm@50keV  : 6.54761E-03    ( -0.00251792   0.00491842 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          40.51 using 59 PHA bins.
# Reduced chi-squared =         0.7233 for     56 degrees of freedom 
# Null hypothesis probability =   9.407968e-01
 
Photon flux (15-150 keV)    in 62.57 sec: 0.492335 ( -0.039426  0.039567 ) ph/cm2/s
Energy fluence (15-150 keV)             : 2.44786e-06 ( -1.91197e-07  1.89908e-07 ) ergs/cm2
 

1-s peak spectrum fit

Power-law model

Time interval is from    1.020 sec. to    2.020 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.08262     ( -0.240541   0.256801 )
Norm@50keV  : 1.58648E-02    ( -0.00252936   0.00249335 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          62.81 using 59 PHA bins.
# Reduced chi-squared =          1.102 for     57 degrees of freedom 
# Null hypothesis probability =   2.781050e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.83725 ( -0.3044  0.30782 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.66821e-07 ( -2.51927e-08  2.52094e-08 ) ergs/cm2
 

Cutoff power-law model

Time interval is from    1.020 sec. to    2.020 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.318488     ( -0.862179   1.18328 )
Epeak [keV] : 132.810      ( -47.9811 -132.804 )
Norm@50keV  : 3.35970E-02    ( -0.0190387   0.0644174 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          60.90 using 59 PHA bins.
# Reduced chi-squared =          1.088 for     56 degrees of freedom 
# Null hypothesis probability =   3.040004e-01
 
Photon flux (15-150 keV)    in 1 sec: 1.79136 ( -0.30744  0.31207 ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.64596e-07 ( -2.5783e-08  2.56388e-08 ) ergs/cm2
 

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = 58.852 sec.
Hardness ratio (energy fluence ratio) = 1.52058303201

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

S(15-50 keV)  = 8.833336e-07
S(50-150 keV) = 1.6108378e-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 = -1.072701464266677E+00, IMY = 4.521030627170247E-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:
-299.608000 -10.064000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.4853  35.3526   67.0  40.4    8.8   0.0420   0.2    1.5	Her X-1                       
239.2187  10.8309    2.0  45.0   50.3   3.9238   5.9 ------	UNKNOWN                       
273.5117  35.9419    2.4  53.7   -1.9   2.3215   4.7 ------	UNKNOWN                       
232.5301  47.5448    2.7  21.6   -7.2   0.6693   4.3 ------	UNKNOWN                       
141.6258  71.9028    3.5  41.0  -98.0   3.1860   3.3 ------	UNKNOWN                       

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

Time interval of the image:
-10.064000 52.508000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
254.3034  35.4339    4.2  40.2    8.8   0.3249   2.7    9.3	Her X-1                       
239.9916  10.8440    2.7  45.5   49.5   1.3854   4.2 ------	UNKNOWN                       
223.9101  10.4371    2.7  37.2   70.0   0.8383   4.3 ------	UNKNOWN                       
152.9402  13.8082    2.1  51.3  177.7   1.0706   5.5 ------	UNKNOWN                       
219.0630  42.7800    2.2  12.1   10.0   0.3556   5.2 ------	UNKNOWN                       
166.5135  28.4189    2.1  32.2 -177.9   0.4686   5.5 ------	UNKNOWN                       
141.7573  30.2669    0.6  49.3 -157.1   3.6467  20.8 ------	UNKNOWN                       
276.6008  67.2314    3.6  45.4  -42.1   0.5876   3.2 ------	UNKNOWN                       

Post-slew image of 15-350 keV band

Time interval of the image: