GRB080121

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 00:03:30 EDT 2014
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/ground_detect_bursts/scripts
==========================================================================
 
  BAT Trigger Time: 222643798.08
               UTC: 2008-01-21T21:29:55.561   [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: 137.257457051   Dec: 41.8392508673  [deg; J2000]
        { 09h 09m 01.8s , +41d 50' 21.3" }
        +/- 2.4791111952 [arcmin] (estimated 90% radius based on SNR)
    SNR: 8.31563059263
 
 
  Angular difference between the analysis and refined position is Usage: arcmin
 
  Partial Coding Fraction: 6.328125e-01    [ including projection effects ]
 
  Duration (found by FRED-model fit)
     T90: 0.32 +/- N/A
        Measured from: 0.048
                   to: 0.368     [s; relative to TRIGTIME]
     T50: 0.128 +/- N/A
        Measured from: 0.128
                   to: 0.256
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    0.496    0.000    0.496
T90     0.320    0.048    0.368
T50     0.128    0.128    0.256
Peak    1.000   -0.281    0.719
 
 
====== 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: 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      -1.614    -0.471      0.446       -           -               -         7.17e-03     -2.06e-03          1.98e-03      72.330   57
CPL     -1.325    -1.072      1.772      107.717    -107.717      -107.717      1.02e-02     -1.02e-02          7.44e-02      72.190   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      -2.224     -0.513     0.433       -           -               -         4.06e-03     -1.48e-03          1.47e-03      69.530   57
CPL     -1.225     -0.891     3.709       27.151      N/A           N/A         1.80e-02        N/A               N/A         68.530   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   5.05e-09  8.66e-09  1.13e-08  3.00e-08  3.32e-08  5.50e-08   erg/cm2
      90%_error_low -1.89e-09 -2.21e-09 -4.22e-09 -1.77e-08 -9.91e-09 -2.28e-08   erg/cm2
      90%_error_hi   2.02e-09  2.20e-09  4.28e-09  3.00e-08  1.03e-08  3.28e-08   erg/cm2
Peak flux       PL   3.37e-01  2.22e-01  9.49e-02  5.57e-02  6.81e-01  7.09e-01   ph/cm2/s
      90%_error_low -9.51e-02 -5.72e-02 -4.21e-02 -3.53e-02 -1.61e-01 -1.72e-01   ph/cm2/s
      90%_error_hi   9.73e-02  5.57e-02  4.74e-02  6.19e-02  1.61e-01  1.75e-01   ph/cm2/s
 
Fluence        CPL   4.87e-09  9.00e-09  1.14e-08  1.81e-08  3.23e-08  4.34e-08   erg/cm2
      90%_error_low -2.17e-09 -2.49e-09 -4.53e-09    N/A    -1.04e-08 -2.06e-08   erg/cm2
      90%_error_hi   2.08e-09  2.79e-09  4.62e-09    N/A     1.09e-08  2.05e-08   erg/cm2
Peak flux      CPL   3.28e-01  2.49e-01  8.14e-02  1.15e-02  6.68e-01  6.70e-01   ph/cm2/s
      90%_error_low -1.02e-01     N/A   -8.14e-02 -1.15e-02 -1.59e-01     N/A     ph/cm2/s
      90%_error_hi   1.02e-01     N/A    5.67e-02  9.60e-02  1.61e-01     N/A     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
137.257 41.839 0.023 21.440 104.585 0.074 8.316 TRIG_00301491
 
Image time interval: 0.000 to 0.496 [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    0.496 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.61352     ( -0.471167   0.445655 )
Norm@50keV  : 7.16685E-03    ( -0.00205888   0.00198082 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          72.33 using 59 PHA bins.
# Reduced chi-squared =          1.269 for     57 degrees of freedom 
# Null hypothesis probability =   8.301247e-02
 
Photon flux (15-150 keV)    in 0.496 sec: 0.924904 ( -0.234769  0.234866 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.31957e-08 ( -9.91201e-09  1.03266e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from    0.000 sec. to    0.496 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.32463     ( -1.08854   1.75574 )
Epeak [keV] : 107.717      ( -106.31 -106.31 )
Norm@50keV  : 1.02344E-02    ( -0.0104487   0.0742308 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          72.19 using 59 PHA bins.
# Reduced chi-squared =          1.289 for     56 degrees of freedom 
# Null hypothesis probability =   7.145672e-02
 
Photon flux (15-150 keV)    in 0.496 sec: 0.915259 ( -0.238509  0.238301 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.23088e-08 ( -1.04342e-08  1.09188e-08 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from   -0.281 sec. to    0.719 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -2.22389     ( -0.513459   0.433013 )
Norm@50keV  : 4.06087E-03    ( -0.00148074   0.00146514 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          69.53 using 59 PHA bins.
# Reduced chi-squared =          1.220 for     57 degrees of freedom 
# Null hypothesis probability =   1.233666e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.680923 ( -0.16071  0.161032 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.83239e-08 ( -1.15174e-08  1.25471e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   -0.281 sec. to    0.719 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.22529     ( -0.890758   3.70891 )
Epeak [keV] : 27.1507      (   )
Norm@50keV  : 1.80182E-02    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          68.53 using 59 PHA bins.
# Reduced chi-squared =          1.224 for     56 degrees of freedom 
# Null hypothesis probability =   1.215481e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.667914 ( -0.158528  0.160745 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.42492e-08 ( -1.14353e-08  1.408e-08 ) ergs/cm2

Time-resolved spectra

Distribution

T90 vs. Hardness ratio plot

T90                                   = N/A sec.
Hardness ratio (energy fluence ratio) = N/A

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

S(15-50 keV)  = N/A
S(50-150 keV) = N/A

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 = -0.0988866503755, IMY = -0.380037565843

Spacecraft aspect plot

Bright source in the event data image

Event data image of 15-350 keV band

Time interval of the image:
0.000000 0.496000
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
137.2574  41.8393    1.4  21.4  104.6   0.0741   8.3 ------	UNKNOWN                       
200.9319  11.3494    2.0  53.6   -4.7   0.1372   5.9 ------	UNKNOWN

Webpage updated on:
Sun Jun 21 01:28:06 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