GRB180718A

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 Ver: batgrbproduct v2.46
    Process Start Time: Wed Jul 18 16:04:59 EDT 2018
             Host Name: bat1
   Current Working Dir: /local/data/bat1/alien/Swift_3rdBATcatalog/event/ground_detect_bursts/scripts
======================================================================

  Trigger: 00848489      Segment: 000

  BAT Trigger Time: 553571885.816
               UTC: 20180718T01:57:44.530   [includes UTCF correction]
       Where From?: Ground analysis (best_duration.txt)
  NOTE: BAT trigger time for ground-detected burst is the T100 start time.
 
  Analysis Position:   [ source = GCN ]
    RA: 336.0186   Dec: 2.7898 
 
  Refined Position:   [ source = BAT pre-slew image ]
    RA: 336.019   Dec: 2.7898  [deg; J2000]
        { 22h 24m 04.6s , +02d 47' 23.3" }
        +/- 3.00825676649 [arcmin] (estimated 90% radius based on SNR)
    SNR: 6.30765882123
 
 
  Angular difference between the analysis and refined position is 0.023972 arcmin
 
  Partial Coding Fraction: 0.25    [ including projection effects ]

  Duration
     T90: 0.0839999914169312 +/- 0.0233238752907961
        Measured from: 0.00800002
                   to: 0.092     [s; relative to TRIGTIME]
     T50: 0.0519999265670776 +/- 0.0256125023115591
        Measured from: 0.016
                   to: 0.068     [s; relative to TRIGTIME]
 
 
====== Table of the duration information =============================
 
        Value   tstart    tstop
T100    0.100    0.000    0.100
T90     0.084    0.008    0.092
T50     0.052    0.016    0.068
Peak    1.000   -0.448    0.552
 
 
====== 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      -4.657    -0.832      0.679       -           -               -         1.07e-03     -7.19e-04          6.92e-04      82.090   57
CPL     -1.000     N/A        N/A          80.000      N/A           N/A         2.10e-04        N/A               N/A         88.450   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      -1.757     -0.549     0.492       -           -               -         7.25e-03     -2.57e-03          2.48e-03      58.080   57
CPL     -0.689     -1.491     4.886       53.933     -49.518       -53.933      2.90e-02     -2.90e-02          3.35e+01      57.300   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   2.94e-09  8.58e-10  1.36e-10  2.48e-11  3.95e-09  3.96e-09   erg/cm2
      90%_error_low -1.98e-09 -5.11e-10 -9.80e-11 -2.09e-11 -2.52e-09 -2.52e-09   erg/cm2
      90%_error_hi   2.00e-09  5.11e-10  9.75e-11  2.97e-11  2.52e-09  2.52e-09   erg/cm2
Peak flux       PL   3.82e-01  3.31e-01  1.96e-01  1.74e-01  9.83e-01  1.08e+00   ph/cm2/s
      90%_error_low -1.65e-01 -1.04e-01 -8.45e-02 -1.10e-01 -3.09e-01 -3.41e-01   ph/cm2/s
      90%_error_hi   1.81e-01  1.04e-01  8.49e-02  1.78e-01  3.10e-01  3.43e-01   ph/cm2/s
 
Fluence        CPL   2.32e-09  1.10e-08  2.34e-09  1.94e-12  1.56e-08  1.56e-08   erg/cm2
      90%_error_low -1.55e-09 -4.70e-09    N/A    -1.73e-12 -5.04e-09 -4.98e-09   erg/cm2
      90%_error_hi   3.97e-09  4.66e-09    N/A     4.10e-12  5.94e-09  6.03e-09   erg/cm2
Peak flux      CPL   3.43e-01  3.78e-01  2.02e-01  5.32e-02  9.62e-01  9.75e-01   ph/cm2/s
      90%_error_low -1.86e-01 -1.34e-01 -2.02e-01 -5.32e-02 -3.15e-01 -3.26e-01   ph/cm2/s
      90%_error_hi   1.97e-01  1.61e-01  1.04e-01  1.79e-01  3.13e-01  3.82e-01   ph/cm2/s
 
======================================================================

Special notes of this burst

Image

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

#   RAcent    DECcent   POSerr    Theta     Phi              Peak Cts       SNR   Name
    336.019   2.790     0.000     34.670    69.207           0.079          6.308 TRIG_00848489
 
Image time interval: 0.065 to 2.273 [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    0.100 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -4.6565     ( -0.833737   0.676788 )
Norm@50keV  : 1.07159E-03    ( -0.000719191   0.000691525 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          82.09 using 59 PHA bins.
# Reduced chi-squared =          1.440 for     57 degrees of freedom 
# Null hypothesis probability =   1.642924e-02
 
Photon flux (15-150 keV)    in 0.1 sec: 1.19595 ( -0.785305  0.78978 ) ph/cm2/s
Energy fluence (15-150 keV)             : 3.94903e-09 ( -2.51948e-09  2.51674e-09 ) ergs/cm2

Cutoff power-law model

Time interval is from    0.000 sec. to    0.100 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1     (       )
Epeak [keV] : 80.0000      (   )
Norm@50keV  : 2.09740E-04    (     )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          88.45 using 59 PHA bins.
# Reduced chi-squared =          1.580 for     56 degrees of freedom 
# Null hypothesis probability =   3.697836e-03
 
Photon flux (15-150 keV)    in 0.1 sec:  (    ) ph/cm2/s
Energy fluence (15-150 keV)             : 1.56236e-08 ( -5.04008e-09  5.94341e-09 ) ergs/cm2

1-s peak spectrum fit

Power-law model

Time interval is from   -0.448 sec. to    0.552 sec.
 
Spectral model in power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -1.75694     ( -0.549084   0.492331 )
Norm@50keV  : 7.25453E-03    ( -0.00257286   0.00247763 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          58.08 using 59 PHA bins.
# Reduced chi-squared =          1.019 for     57 degrees of freedom 
# Null hypothesis probability =   4.353983e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.983499 ( -0.309243  0.309631 ) ph/cm2/s
Energy fluence (15-150 keV)             : 6.69268e-08 ( -2.34958e-08  2.42701e-08 ) ergs/cm2

Cutoff power-law model

Time interval is from   -0.448 sec. to    0.552 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters  : value       lower 90%   higher 90%
Photon index: -0.688847     ( -1.49091   4.88613 )
Epeak [keV] : 53.9330      ( -49.5157 -53.9309 )
Norm@50keV  : 2.89871E-02    ( -0.0289904   33.5399 )
------------------------------------------------------------
#Fit statistic : Chi-Squared =          57.30 using 59 PHA bins.
# Reduced chi-squared =          1.023 for     56 degrees of freedom 
# Null hypothesis probability =   4.268534e-01
 
Photon flux (15-150 keV)    in 1 sec: 0.962432 ( -0.314628  0.313218 ) ph/cm2/s
Energy fluence (15-150 keV)             : 5.60544e-08 ( -5.41312e-08  2.39474e-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.

Spacecraft aspect plot

Bright source in the event data image

Event data image of 15-350 keV band

Time interval of the image:
0.065000 2.272600
 
# RAcent  DECcent POSerr Theta    Phi  PeakCts   SNR AngSep     Name
#  [deg]    [deg]    ['] [deg]  [deg]                   [']
299.6383  35.2947    5.0  47.9  140.8   0.1763   2.3    6.1	Cyg X-1                       
308.0524  40.9637   52.2  40.6  147.7   0.0076   0.2    2.7	Cyg X-3                       
326.1921  38.3167  331.0  26.6  144.0   0.0007   0.0    1.0	Cyg X-2                       
285.8998  64.6886    2.4  54.5  179.5   0.3288   4.8 ------	UNKNOWN                       
 16.0325  73.6841    2.2  43.8 -143.2   0.1692   5.2 ------	UNKNOWN

Webpage updated on:
Sat Aug 11 22:42:30 EDT 2018

Analysis Summary

Notes:

Image

Pre-slew 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

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