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
133.4917 13.4875 0.0158 35.5498 74.6875 3.0274022 12.226 TRIG_00451191
Foreground time interval of the image:
13.656 40.888 (delta_t = 27.232 [sec])
Background time interval of the image:
-1.699 13.656 (delta_t = 15.355 [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
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 80.000000
8 ms binning
From T100_start-3 s to T100_start+3 s
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 80.000000
2 ms binning
From T100_start-1 s to T100_start+1 s
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 80.000000
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 13.656 sec. to 40.888 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.53709 ( -0.13488 0.135966 )
Norm@50keV : 6.95965E-03 ( -0.000579898 0.00057673 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.01 using 59 PHA bins.
# Reduced chi-squared = 1.158 for 57 degrees of freedom
# Null hypothesis probability = 1.936363e-01
Photon flux (15-150 keV) in 27.23 sec: 0.877796 ( -0.07077 0.0708308 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.78742e-06 ( -1.61723e-07 1.63332e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from 13.656 sec. to 40.888 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.775524 ( -0.669351 0.570913 )
Epeak [keV] : 74.7489 ( -17.0333 81.6631 )
Norm@50keV : 1.77865E-02 ( -0.00884151 0.0224979 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.58 using 59 PHA bins.
# Reduced chi-squared = 1.082 for 56 degrees of freedom
# Null hypothesis probability = 3.141741e-01
Photon flux (15-150 keV) in 27.23 sec: 0.850876 ( -0.073685 0.07362 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.66338e-06 ( -1.85766e-07 1.87879e-07 ) ergs/cm2
Band function
Time interval is from 13.656 sec. to 40.888 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.61518 ( -4.68408 -4.61518 )
beta : -1.81891 ( -0.209483 0.191213 )
Epeak [keV] : 30.1603 ( -3.58716 3.47301 )
Norm@50keV : 141.362 ( -11.0889 585.88 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.15 using 59 PHA bins.
# Reduced chi-squared = 1.003 for 55 degrees of freedom
# Null hypothesis probability = 4.690062e-01
Photon flux (15-150 keV) in 27.23 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.70732e-06 ( -1.70713e-06 -1.675e-07 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 13.2701 (-1.25756 1.42839)
R^2/D10^2 : 0.153710 (-0.0473264 0.0665171)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 82.60 using 59 PHA bins.
# Reduced chi-squared = 1.449 for 57 degrees of freedom
# Null hypothesis probability = 1.496462e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.562e-07 2.309e-08
25- 50 5.501e-07 5.323e-08
50-150 6.197e-07 1.072e-07
15-150 1.326e-06 1.390e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 189.224 (-64.1566 -189.224)
Norm : 3.60261 (-0.292914 0.320952)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.36 using 59 PHA bins.
# Reduced chi-squared = 1.094 for 57 degrees of freedom
# Null hypothesis probability = 2.913480e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.459e-07 7.859e-08
25- 50 4.701e-07 2.141e-07
50-150 1.013e-06 5.306e-07
15-150 1.729e-06 8.711e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 8.49253 (-1.81089 1.92213)
R1^2/D10^2 : 0.533154 (-0.240934 0.541669)
kT2 [keV] : 29.8136 (-9.13519 30.6249)
R2^2/D10^2 : 5.86094E-03 (-0.00513958 0.0174762)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.33 using 59 PHA bins.
# Reduced chi-squared = 1.024 for 55 degrees of freedom
# Null hypothesis probability = 4.250706e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.195e-07 5.852e-08
25- 50 5.190e-07 1.474e-07
50-150 9.843e-07 4.617e-07
15-150 1.723e-06 6.346e-07
Peak spectrum fit
Power-law model
Time interval is from 19.004 sec. to 20.004 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.19580 ( -0.307796 0.296178 )
Norm@50keV : 1.75705E-02 ( -0.00312695 0.00312367 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.46 using 59 PHA bins.
# Reduced chi-squared = 1.166 for 57 degrees of freedom
# Null hypothesis probability = 1.831840e-01
Photon flux (15-150 keV) in 1 sec: 2.06120 ( -0.378948 0.380125 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.78471e-07 ( -3.43776e-08 3.46891e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 19.004 sec. to 20.004 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.753989 ( -1.40042 0.684624 )
Epeak [keV] : 154.775 ( -154.784 -154.784 )
Norm@50keV : 2.83412E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.00 using 59 PHA bins.
# Reduced chi-squared = 1.179 for 56 degrees of freedom
# Null hypothesis probability = 1.694589e-01
Photon flux (15-150 keV) in 1 sec: 2.03037 ( -0.39046 0.38838 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.74891e-07 ( -3.5939e-08 3.5985e-08 ) ergs/cm2
Band function
Time interval is from 19.004 sec. to 20.004 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.753773 ( -0.477763 1.17263 )
beta : -10.00000 ( 10 20 )
Epeak [keV] : 154.658 ( -68.9328 -154.658 )
Norm@50keV : 2.83507E-02 ( -0.0134948 0.0851841 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.00 using 59 PHA bins.
# Reduced chi-squared = 1.200 for 55 degrees of freedom
# Null hypothesis probability = 1.471027e-01
Photon flux (15-150 keV) in 1 sec: 2.06418 ( ) 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] : 20.2405 (-4.05342 5.51954)
R^2/D10^2 : 9.25326E-02 (-0.0507111 0.102493)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 71.09 using 59 PHA bins.
# Reduced chi-squared = 1.247 for 57 degrees of freedom
# Null hypothesis probability = 9.925337e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.273e-09 2.768e-09
25- 50 3.651e-08 1.229e-08
50-150 1.111e-07 3.610e-08
15-150 1.548e-07 5.092e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 8.57953 (-1.55816 1.55802)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 70.07 using 59 PHA bins.
# Reduced chi-squared = 1.229 for 57 degrees of freedom
# Null hypothesis probability = 1.144914e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.137e-08 1.231e-08
25- 50 4.112e-08 2.383e-08
50-150 9.017e-08 5.230e-08
15-150 1.527e-07 8.680e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 5.56681 (-2.10242 3.92415)
R1^2/D10^2 : 3.69872 (-3.18776 11.7829)
kT2 [keV] : 26.0393 (-6.48295 13.2886)
R2^2/D10^2 : 3.63459E-02 (-0.0266678 0.0468515)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.04 using 59 PHA bins.
# Reduced chi-squared = 1.164 for 55 degrees of freedom
# Null hypothesis probability = 1.891068e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.775e-08 1.047e-08
25- 50 3.569e-08 1.854e-08
50-150 1.218e-07 6.935e-08
15-150 1.753e-07 9.400e-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: 1.53709 ( -0.13488 0.135966 )
Norm@50keV : 6.95965E-03 ( -0.000579898 0.00057673 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 66.01 using 59 PHA bins.
# Reduced chi-squared = 1.158 for 57 degrees of freedom
# Null hypothesis probability = 1.936363e-01
Photon flux (15-150 keV) in 27.23 sec: 0.877796 ( -0.07077 0.0708308 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.78742e-06 ( -1.61723e-07 1.63332e-07 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.775524 ( -0.669351 0.570913 )
Epeak [keV] : 74.7489 ( -17.0333 81.6631 )
Norm@50keV : 1.77865E-02 ( -0.00884151 0.0224979 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.58 using 59 PHA bins.
# Reduced chi-squared = 1.082 for 56 degrees of freedom
# Null hypothesis probability = 3.141741e-01
Photon flux (15-150 keV) in 27.23 sec: 0.850876 ( -0.073685 0.07362 ) ph/cm2/s
Energy fluence (15-150 keV) : 1.66338e-06 ( -1.85766e-07 1.87879e-07 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 4.61518 ( -4.68408 -4.61518 )
beta : -1.81891 ( -0.209483 0.191213 )
Epeak [keV] : 30.1603 ( -3.58716 3.47301 )
Norm@50keV : 141.362 ( -11.0889 585.88 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.15 using 59 PHA bins.
# Reduced chi-squared = 1.003 for 55 degrees of freedom
# Null hypothesis probability = 4.690062e-01
Photon flux (15-150 keV) in 27.23 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 1.70732e-06 ( -1.70713e-06 -1.675e-07 ) ergs/cm2
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 4.50e-07
S(50-100 keV) = 6.20e-07
T90 vs. Hardness ratio plot
T90 = 24 sec.
Hardness ratio (energy fluence ratio) = 1.37778
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.63937
Count Ratio (50-100 keV) / (15-25 keV) = 1.06176
Mask shadow pattern
IMX = 1.887154681936289E-01, IMY = -6.892353721042619E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 80.000000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 80.000000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 80.000000
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:
-1.699410 13.656000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
83.6096 21.9944 0.9 21.5 -40.0 0.5682 12.6 1.8 Crab
121.9490 -43.4837 2.1 53.8 158.6 1.3828 5.5 ------ UNKNOWN
106.2725 41.8442 2.3 36.7 9.8 0.3152 5.1 ------ UNKNOWN
97.9609 -37.6260 2.1 43.5 -179.9 0.3768 5.4 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
13.656000 40.888000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
83.7084 22.1563 7.5 21.5 -39.5 0.1487 1.5 9.5 Crab
133.4917 13.4875 0.9 35.5 74.7 3.0278 12.2 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
Plot creation:
Sat May 30 22:31:51 EDT 2015