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
260.1983 69.3540 0.0166 14.3599 130.2724 0.5544809 11.534 TRIG_00261132
Foreground time interval of the image:
-1.920 19.080 (delta_t = 21.000 [sec])
Background time interval of the image:
-83.419 -1.920 (delta_t = 81.499 [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 2.048000
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 2.048000
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 2.048000
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 -1.920 sec. to 19.080 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.80522 ( -0.216196 0.225975 )
Norm@50keV : 1.70559E-03 ( -0.000234389 0.00022747 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.52 using 59 PHA bins.
# Reduced chi-squared = 1.044 for 57 degrees of freedom
# Null hypothesis probability = 3.839680e-01
Photon flux (15-150 keV) in 21 sec: 0.235504 ( -0.0265501 0.0265638 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.29673e-07 ( -4.53909e-08 4.64123e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -1.920 sec. to 19.080 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.02358 ( )
Epeak [keV] : 10.2558 ( )
Norm@50keV : 1.32003E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.46 using 59 PHA bins.
# Reduced chi-squared = 1.062 for 56 degrees of freedom
# Null hypothesis probability = 3.508177e-01
Photon flux (15-150 keV) in 21 sec: 0.235544 ( -0.026644 0.026461 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.28717e-07 ( -4.61538e-08 4.66158e-08 ) ergs/cm2
Band function
Time interval is from -1.920 sec. to 19.080 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.45434 ( 1.44687 1.44687 )
beta : -1.80533 ( 1.80605 0.216742 )
Epeak [keV] : 21.0277 ( -26.7141 -26.7141 )
Norm@50keV : 3.83320E-03 ( -0.00222524 0.308323 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.52 using 59 PHA bins.
# Reduced chi-squared = 1.082 for 55 degrees of freedom
# Null hypothesis probability = 3.145291e-01
Photon flux (15-150 keV) in 21 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] : 11.5602 (-1.8683 2.27422)
R^2/D10^2 : 6.21607E-02 (-0.0296088 0.0570661)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 88.53 using 59 PHA bins.
# Reduced chi-squared = 1.553 for 57 degrees of freedom
# Null hypothesis probability = 4.705147e-03
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.675e-08 8.274e-09
25- 50 1.106e-07 1.901e-08
50-150 8.661e-08 2.449e-08
15-150 2.340e-07 3.871e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 103.352 (-37.4701 93.5228)
Norm : 1.02578 (-0.153177 0.191533)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 61.58 using 59 PHA bins.
# Reduced chi-squared = 1.080 for 57 degrees of freedom
# Null hypothesis probability = 3.156279e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.630e-08 9.230e-09
25- 50 9.799e-08 1.415e-08
50-150 1.618e-07 7.296e-08
15-150 3.160e-07 8.358e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 4.62048 (-1.22147 1.60676)
R1^2/D10^2 : 1.48065 (-1.03512 4.58671)
kT2 [keV] : 20.7566 (-4.74305 8.37602)
R2^2/D10^2 : 6.17217E-03 (-0.00430204 0.0097074)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.55 using 59 PHA bins.
# Reduced chi-squared = 1.065 for 55 degrees of freedom
# Null hypothesis probability = 3.464803e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 6.515e-08 3.299e-08
25- 50 8.327e-08 3.131e-08
50-150 1.743e-07 9.015e-08
15-150 3.228e-07 1.428e-07
Peak spectrum fit
Power-law model
Time interval is from 1.080 sec. to 2.080 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 1.99615 ( -0.399458 0.462777 )
Norm@50keV : 4.12314E-03 ( -0.00120373 0.00112288 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.30 using 59 PHA bins.
# Reduced chi-squared = 1.128 for 57 degrees of freedom
# Null hypothesis probability = 2.363403e-01
Photon flux (15-150 keV) in 1 sec: 0.617380 ( -0.124168 0.124172 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.8015e-08 ( -9.8406e-09 1.03591e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 1.080 sec. to 2.080 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.06071 ( -1.4962 0.0533208 )
Epeak [keV] : 32.2053 ( )
Norm@50keV : 3.72323E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.24 using 59 PHA bins.
# Reduced chi-squared = 1.147 for 56 degrees of freedom
# Null hypothesis probability = 2.100890e-01
Photon flux (15-150 keV) in 1 sec: 0.617408 ( -0.124528 0.123661 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.77837e-08 ( -1.00845e-08 1.04412e-08 ) ergs/cm2
Band function
Time interval is from 1.080 sec. to 2.080 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.54266 ( 1.54572 1.54572 )
beta : -1.98274 ( 1.98775 0.391372 )
Epeak [keV] : 16.0552 ( -12.2041 -12.2041 )
Norm@50keV : 1.07922E-02 ( -0.011563 6.90778 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.31 using 59 PHA bins.
# Reduced chi-squared = 1.169 for 55 degrees of freedom
# Null hypothesis probability = 1.828664e-01
Photon flux (15-150 keV) in 1 sec: ( ) ph/cm2/s
Energy fluence (15-150 keV) : 3.6985e-08 ( -3.6978e-08 -3.6985e-08 ) ergs/cm2
Single BB
Spectral model blackbody:
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 10.5180 (-2.8375 3.40507)
R^2/D10^2 : 0.231544 (-0.148572 0.516743)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 73.21 using 59 PHA bins.
# Reduced chi-squared = 1.284 for 57 degrees of freedom
# Null hypothesis probability = 7.278470e-02
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.297e-09 2.564e-09
25- 50 1.412e-08 5.464e-09
50-150 8.514e-09 4.712e-09
15-150 2.793e-08 1.109e-08
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 70.8232 (-34.9998 122.386)
Norm : 3.00106 (-0.805853 1.34072)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 65.28 using 59 PHA bins.
# Reduced chi-squared = 1.145 for 57 degrees of freedom
# Null hypothesis probability = 2.112100e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 7.709e-09 2.250e-09
25- 50 1.230e-08 4.015e-09
50-150 1.594e-08 1.214e-08
15-150 3.595e-08 1.577e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 3.44608 (-2.64592 2.36269)
R1^2/D10^2 : 15.4864 (-14.0134 2.33038e+07)
kT2 [keV] : 15.8477 (-4.96315 10.6636)
R2^2/D10^2 : 4.17122E-02 (-0.0345255 0.135778)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.35 using 59 PHA bins.
# Reduced chi-squared = 1.152 for 55 degrees of freedom
# Null hypothesis probability = 2.056126e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 8.688e-09 4.947e-09
25- 50 1.056e-08 5.900e-09
50-150 1.585e-08 1.011e-08
15-150 3.510e-08 1.815e-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: 1.80522 ( -0.216196 0.225975 )
Norm@50keV : 1.70559E-03 ( -0.000234389 0.00022747 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.52 using 59 PHA bins.
# Reduced chi-squared = 1.044 for 57 degrees of freedom
# Null hypothesis probability = 3.839680e-01
Photon flux (15-150 keV) in 21 sec: 0.235504 ( -0.0265501 0.0265638 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.29673e-07 ( -4.53909e-08 4.64123e-08 ) ergs/cm2
Cutoff power-law model
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 2.02358 ( )
Epeak [keV] : 10.2558 ( )
Norm@50keV : 1.32003E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.46 using 59 PHA bins.
# Reduced chi-squared = 1.062 for 56 degrees of freedom
# Null hypothesis probability = 3.508177e-01
Photon flux (15-150 keV) in 21 sec: 0.235544 ( -0.026644 0.026461 ) ph/cm2/s
Energy fluence (15-150 keV) : 3.28717e-07 ( -4.61538e-08 4.66158e-08 ) ergs/cm2
Band function
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -1.45434 ( 1.44687 1.44687 )
beta : -1.80533 ( 1.80605 0.216742 )
Epeak [keV] : 21.0277 ( -26.7141 -26.7141 )
Norm@50keV : 3.83320E-03 ( -0.00222524 0.308323 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 59.52 using 59 PHA bins.
# Reduced chi-squared = 1.082 for 55 degrees of freedom
# Null hypothesis probability = 3.145291e-01
Photon flux (15-150 keV) in 21 sec: ( ) 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) = 9.30e-08
S(50-100 keV) = 1.06e-07
T90 vs. Hardness ratio plot
T90 = 18 sec.
Hardness ratio (energy fluence ratio) = 1.13978
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 0.921388
Count Ratio (50-100 keV) / (15-25 keV) = 0.585549
Mask shadow pattern
IMX = -1.654912484241922E-01, IMY = -1.953310178599256E-01
TIME vs. PHA plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 2.048000
TIME vs. DetID plot around the trigger time
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 2.048000
100 us light curve (15-350 keV)
Blue+Cyan dotted lines: Time interval of the scaled map
From 0.000000 to 2.048000
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:
-83.419410 -1.920000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.5487 35.1735 8.2 26.1 16.2 -0.1373 -1.4 11.1 Her X-1
268.3083 -1.4102 4.9 58.6 -17.7 -1.2849 -2.4 4.4 SW J1753.5-0127
288.7639 10.9047 2.3 46.9 -44.0 1.3527 5.1 3.2 GRS 1915+105
299.5749 35.2194 0.6 26.8 -73.1 2.3115 18.4 1.3 Cyg X-1
308.0962 40.9716 1.6 26.0 -93.0 0.8575 7.3 1.3 Cyg X-3
326.1791 38.3286 79.1 37.4 -109.1 0.0314 0.1 0.5 Cyg X-2
263.1134 24.1479 2.2 34.0 -5.4 0.5564 5.3 ------ UNKNOWN
256.8077 4.3892 1.9 54.6 -3.0 1.6922 6.1 ------ UNKNOWN
296.7772 46.3833 2.2 16.4 -86.3 0.4752 5.2 ------ UNKNOWN
308.0457 37.7277 1.8 28.4 -88.4 0.8713 6.5 ------ UNKNOWN
Pre-slew background subtracted image of 15-350 keV band
Time interval of the image:
-1.920000 19.080000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.5912 35.1657 0.0 26.1 16.2 0.0386 0.7 12.5 Her X-1
268.3580 -1.4132 4.3 58.6 -17.8 0.7737 2.7 2.4 SW J1753.5-0127
288.6975 10.9400 13.7 46.9 -43.9 -0.1256 -0.8 5.9 GRS 1915+105
299.8442 35.1953 0.0 26.9 -73.5 0.1381 2.1 12.5 Cyg X-1
308.0075 40.8333 11.7 26.0 -92.7 0.0675 1.0 8.5 Cyg X-3
326.2367 38.4778 5.8 37.3 -109.3 0.2282 2.0 9.9 Cyg X-2
260.2003 69.3543 1.0 14.4 130.3 0.5531 11.5 ------ UNKNOWN
277.4047 13.6497 2.6 43.2 -28.7 0.3676 4.4 ------ UNKNOWN
Post-slew image of 15-350 keV band
Time interval of the image:
66.380600 962.131100
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
254.6279 35.3615 5.7 34.1 -12.7 -0.8979 -2.0 8.4 Her X-1
299.6074 35.2056 0.8 40.3 -74.1 21.0199 15.2 0.9 Cyg X-1
308.0207 40.9678 3.2 37.6 -87.3 5.5022 3.5 4.2 Cyg X-3
46.0435 49.7755 3.2 58.3 -175.6 10.6944 3.6 ------ UNKNOWN
23.7887 57.4179 2.6 46.9 -162.9 3.3471 4.4 ------ UNKNOWN
259.9962 17.9218 2.9 51.4 -20.6 4.1150 4.0 ------ UNKNOWN
300.3505 38.4930 4.2 37.5 -76.8 2.9960 2.7 ------ UNKNOWN
Plot creation:
Sun May 31 10:52:32 EDT 2015