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
49.6971 -46.3883 0.0062 22.2086 -78.8115 2.0703434 30.925 TRIG_00111529
Foreground time interval of the image:
-0.620 29.716 (delta_t = 30.336 [sec])
Background time interval of the image:
-299.608 -0.620 (delta_t = 298.988 [sec])
Lightcurves
Notes:
- 1) The mask-weighted light curves are using the flight position.
- 2) Multiple plots of different time binning/intervals are shown to cover all scenarios of short/long GRBs, rate/image triggers, and real/false positives.
- 3) For all the mask-weighted lightcurves, the y-axis units are counts/sec/det where a det is 0.4 x 0.4 = 0.16 sq cm.
- 4) The verticle lines correspond to following: green dotted lines are T50 interval, black dotted lines are T90 interval, blue solid line(s) is a spacecraft slew start time, and orange solid line(s) is a spacecraft slew end time.
- 5) Time of each bin is in the middle of the bin.
1 s binning
From T0-310 s to T0+310 s
From T100_start - 20 s to T100_end + 30 s
Full time interval
64 ms binning
Full time interval
From T100_start to T100_end
From T0-5 sec to T0+5 sec
16 ms binning
From T100_start-5 s to T100_start+5 s
8 ms binning
From T100_start-3 s to T100_start+3 s
2 ms binning
From T100_start-1 s to T100_start+1 s
SN=5 or 10 sec. binning (whichever binning is satisfied first)
SN=5 or 10 sec. binning (T < 200 sec)
Quad-rate summed light curves (from T0-300s to T0+1000s)
Spectral Evolution
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 -0.620 sec. to 29.716 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.88812 ( -0.0909042 0.0925067 )
Norm@50keV : 4.09445E-03 ( -0.000230425 0.000228579 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.18 using 59 PHA bins.
# Reduced chi-squared = 1.073 for 57 degrees of freedom
# Null hypothesis probability = 3.282111e-01
Photon flux (15-150 keV) in 30.34 sec: 0.584655 ( -0.0287639 0.0287938 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14201e-06 ( -6.35265e-08 6.41096e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.620 sec. to 29.716 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.03216 ( -0.451011 0.407449 )
Epeak [keV] : 49.2346 ( -5.90641 9.4415 )
Norm@50keV : 1.21698E-02 ( -0.00485666 0.009379 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.93 using 59 PHA bins.
# Reduced chi-squared = 0.8380 for 56 degrees of freedom
# Null hypothesis probability = 8.008275e-01
Photon flux (15-150 keV) in 30.34 sec: 0.557858 ( -0.030965 0.031039 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.04442e-06 ( -7.35957e-08 7.5847e-08 ) ergs/cm2
Band function
Time interval is from -0.620 sec. to 29.716 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.03193 ( -0.370381 0.433407 )
beta : -10.0000 ( 10 1.77636e-15 )
Epeak [keV] : 49.2255 ( -5.9025 9.43185 )
Norm@50keV : 1.21722E-02 ( -0.0048599 0.00938317 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.93 using 59 PHA bins.
# Reduced chi-squared = 0.8532 for 55 degrees of freedom
# Null hypothesis probability = 7.723355e-01
Photon flux (15-150 keV) in 30.34 sec: 0.558633 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 11.0085 (-0.629848 0.671565)
R^2/D10^2 : 0.187185 (-0.0377861 0.0471632)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 104.35 using 59 PHA bins.
# Reduced chi-squared = 1.8307 for 57 degrees of freedom
# Null hypothesis probability = 1.320117e-04
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.438e-07 1.204e-08
25- 50 4.071e-07 2.078e-08
50-150 2.788e-07 3.606e-08
15-150 8.297e-07 4.688e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 80.6714 (-12.4901 16.4361)
Norm : 2.72278 (-0.205426 0.22753)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 48.01 using 59 PHA bins.
# Reduced chi-squared = 0.8422 for 57 degrees of freedom
# Null hypothesis probability = 7.961177e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.145e-07 1.478e-08
25- 50 3.538e-07 1.654e-08
50-150 5.022e-07 6.053e-08
15-150 1.070e-06 7.024e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.48931 (-1.01335 1.06518)
R1^2/D10^2 : 0.883055 (-0.334872 0.653487)
kT2 [keV] : 19.3321 (-3.05249 4.66454)
R2^2/D10^2 : 1.50669E-02 (-0.00884715 0.0162106)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 43.46 using 59 PHA bins.
# Reduced chi-squared = 0.7901 for 55 degrees of freedom
# Null hypothesis probability = 8.695011e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.997e-07 5.470e-08
25- 50 3.583e-07 7.788e-08
50-150 4.721e-07 2.088e-07
15-150 1.030e-06 2.966e-07
Peak spectrum fit
Power-law model
Time interval is from 28.580 sec. to 29.580 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.64235 ( -0.0978626 0.0992584 )
Norm@50keV : 2.48139E-02 ( -0.00153675 0.00152783 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 72.04 using 59 PHA bins.
# Reduced chi-squared = 1.264 for 57 degrees of freedom
# Null hypothesis probability = 8.656552e-02
Photon flux (15-150 keV) in 1 sec: 3.23196 ( -0.188473 0.18858 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.30959e-07 ( -1.52161e-08 1.53242e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 28.580 sec. to 29.580 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.805755 ( -0.462061 0.418565 )
Epeak [keV] : 67.2495 ( -10.1553 22.4428 )
Norm@50keV : 6.87665E-02 ( -0.0269682 0.0507474 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.29 using 59 PHA bins.
# Reduced chi-squared = 1.059 for 56 degrees of freedom
# Null hypothesis probability = 3.564918e-01
Photon flux (15-150 keV) in 1 sec: 3.12569 ( -0.19509 0.19517 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.16194e-07 ( -1.6615e-08 1.6838e-08 ) ergs/cm2
Band function
Time interval is from 28.580 sec. to 29.580 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.805706 ( -0.334712 0.535564 )
beta : -10.0000 ( 10 1.06581e-13 )
Epeak [keV] : 67.2365 ( -8.7993 22.4386 )
Norm@50keV : 6.87683E-02 ( -0.0269732 0.0508306 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.29 using 59 PHA bins.
# Reduced chi-squared = 1.078 for 55 degrees of freedom
# Null hypothesis probability = 3.219727e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 13.2333 (-0.916496 0.98619)
R^2/D10^2 : 0.566471 (-0.129368 0.167264)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 105.29 using 59 PHA bins.
# Reduced chi-squared = 1.8472 for 57 degrees of freedom
# Null hypothesis probability = 1.046514e-04
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.103e-08 2.250e-09
25- 50 7.382e-08 5.300e-09
50-150 8.258e-08 1.096e-08
15-150 1.774e-07 1.230e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 143.427 ( )
Norm : 13.5160 (-0.876861 1.03626)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.70 using 59 PHA bins.
# Reduced chi-squared = 1.100 for 57 degrees of freedom
# Null hypothesis probability = 2.812929e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.469e-08 2.955e-09
25- 50 6.394e-08 7.350e-09
50-150 1.242e-07 4.139e-08
15-150 2.228e-07 5.035e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 6.66038 (-1.23547 1.41651)
R1^2/D10^2 : 3.82134 (-1.72783 3.80248)
kT2 [keV] : 20.9562 (-3.09331 4.85785)
R2^2/D10^2 : 8.08031E-02 (-0.0461167 0.0747997)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.16 using 59 PHA bins.
# Reduced chi-squared = 1.021 for 55 degrees of freedom
# Null hypothesis probability = 4.313107e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.250e-08 8.580e-09
25- 50 6.645e-08 1.342e-08
50-150 1.172e-07 3.494e-08
15-150 2.161e-07 5.795e-08
Pre-slew spectrum (Pre-slew PHA with pre-slew DRM)
Power-law model
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.88812 ( -0.0909042 0.0925067 )
Norm@50keV : 4.09445E-03 ( -0.000230425 0.000228579 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.18 using 59 PHA bins.
# Reduced chi-squared = 1.073 for 57 degrees of freedom
# Null hypothesis probability = 3.282111e-01
Photon flux (15-150 keV) in 30.34 sec: 0.584655 ( -0.0287639 0.0287938 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.14201e-06 ( -6.35265e-08 6.41096e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.03216 ( -0.451011 0.407449 )
Epeak [keV] : 49.2346 ( -5.90641 9.4415 )
Norm@50keV : 1.21698E-02 ( -0.00485666 0.009379 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.93 using 59 PHA bins.
# Reduced chi-squared = 0.8380 for 56 degrees of freedom
# Null hypothesis probability = 8.008275e-01
Photon flux (15-150 keV) in 30.34 sec: 0.557858 ( -0.030965 0.031039 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.04442e-06 ( -7.35957e-08 7.5847e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.03193 ( -0.370381 0.433407 )
beta : -10.0000 ( 10 5.32907e-15 )
Epeak [keV] : 49.2255 ( -5.9025 9.43185 )
Norm@50keV : 1.21722E-02 ( -0.0048599 0.00938317 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 46.93 using 59 PHA bins.
# Reduced chi-squared = 0.8532 for 55 degrees of freedom
# Null hypothesis probability = 7.723355e-01
Photon flux (15-150 keV) in 30.34 sec: 0.558633 ( ) ph/cm2/s
Energy fluence (15-150 keV) : 0 ( 0 0 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 3.32e-07
S(50-100 keV) = 3.59e-07
T90 vs. Hardness ratio plot
T90 = 16.1240000128746 sec.
Hardness ratio (energy fluence ratio) = 1.08133
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.24884
Count Ratio (50-100 keV) / (15-25 keV) = 0.652201
Mask shadow pattern
IMX = 7.921960456349829E-02, IMY = 4.005086390093962E-01
TIME vs. PHA plot around the trigger time
TIME vs. DetID plot around the trigger time
100 us light curve (15-350 keV)
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 -0.620000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5424 -40.5595 0.9 38.1 81.6 7.5343 12.6 0.7 Vela X-1
170.3066 -60.6232 34.1 42.1 127.3 0.2147 0.3 0.3 Cen X-3
186.5540 -62.7816 2.4 46.5 136.8 3.7866 4.8 2.9 GX 301-2
63.8756 -12.6890 2.3 47.0 -29.3 1.8503 5.1 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-0.620000 29.716000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.5420 -40.5869 5.6 38.1 81.6 -0.3632 -2.1 2.0 Vela X-1
170.0651 -60.5847 17.0 42.1 127.1 -0.1256 -0.7 7.7 Cen X-3
186.7491 -62.7819 27.6 46.6 136.9 0.0974 0.4 2.6 GX 301-2
49.6972 -46.3883 0.4 22.2 -78.8 2.0700 30.9 ------ UNKNOWN
41.9572 -41.8623 2.0 29.3 -80.3 0.4443 5.7 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
Plot creation:
Sun May 31 17:19:35 EDT 2015