Special notes of this burst
Image
15.0-350.0 keV image (Event data)
#RAcent DECcent POSerr Theta Phi Peak_Cts SNR Name
30.958 -16.946 0.027 44.822 45.812 0.322 7.038 TRIG_00376211
Image time interval: 0.000 to 0.960 [sec]
Lightcurves
Notes:
- 1) 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.
- 2) 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 (for the best duration plot, slew times are marked by green arrows).
- 3) For lightcurves in unit of count rate, time of each bin is in the middle of the bin.
Best duration plot
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) For long bursts, a spectral fit of 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.
- 4) For short bursts (T90<1sec), the specrtum is also fit with Blackbody, OTTB, and Double Blackbody.
Time averaged spectrum fit using the pre-slew DRM
Power-law model
Time interval is from 0.000 sec. to 0.960 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.592714 ( -0.544973 0.454056 )
Norm@50keV : 2.02170E-02 ( -0.00621943 0.00558269 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.71 using 59 PHA bins.
# Reduced chi-squared = 0.9774 for 57 degrees of freedom
# Null hypothesis probability = 5.234674e-01
Photon flux (15-150 keV) in 0.96 sec: 2.36254 ( -0.60184 0.605409 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.49063e-07 ( -5.91625e-08 5.90842e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.000 sec. to 0.960 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.598043 ( -0.829426 0.903775 )
Epeak [keV] : 9999.35 ( -9999.36 -9999.36 )
Norm@50keV : 2.04875E-02 ( -0.00580796 0.0285543 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.74 using 59 PHA bins.
# Reduced chi-squared = 0.9953 for 56 degrees of freedom
# Null hypothesis probability = 4.848219e-01
Photon flux (15-150 keV) in 0.96 sec: 2.38011 ( -0.61576 0.58834 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.49502e-07 ( -5.95411e-08 5.80963e-08 ) ergs/cm2
Band function
Time interval is from 0.000 sec. to 0.960 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : -0.787338 ( 0.787338 0.787338 )
beta : -0.592689 ( -0.453622 0.545093 )
Epeak [keV] : 16.9701 ( -16.9701 -16.9701 )
Norm@50keV : 2.87179E-02 ( -0.0140812 236477 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 55.71 using 59 PHA bins.
# Reduced chi-squared = 1.013 for 55 degrees of freedom
# Null hypothesis probability = 4.477958e-01
Photon flux (15-150 keV) in 0.96 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] : 36.9741 (-12.1604 37.4035)
R^2/D10^2 : 2.07775E-02 (-0.0207302 0.0430526)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 60.17 using 59 PHA bins.
# Reduced chi-squared = 1.056 for 57 degrees of freedom
# Null hypothesis probability = 3.618275e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 3.719e-09 2.226e-09
25- 50 2.476e-08 1.511e-08
50-150 2.140e-07 1.273e-07
15-150 2.425e-07 1.325e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 9.45602 (-2.5012 2.50106)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 68.14 using 59 PHA bins.
# Reduced chi-squared = 1.195 for 57 degrees of freedom
# Null hypothesis probability = 1.482722e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.260e-08 1.375e-08
25- 50 4.348e-08 2.658e-08
50-150 9.535e-08 5.693e-08
15-150 1.614e-07 9.734e-08
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.00307 (-3.28224 3.61143)
R1^2/D10^2 : 0.914743 (-0.813953 7.69173)
kT2 [keV] : 176.791 (-176.599 -176.599)
R2^2/D10^2 : 8.53671E-04 (-0.000351795 0.019999)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 53.98 using 59 PHA bins.
# Reduced chi-squared = 0.9814 for 55 degrees of freedom
# Null hypothesis probability = 5.137585e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.478e-08 8.866e-09
25- 50 3.728e-08 2.035e-08
50-150 1.961e-07 5.434e-08
15-150 2.482e-07 6.994e-08
Peak spectrum fit
Power-law model
Time interval is from -0.244 sec. to 0.756 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.832574 ( -0.451085 0.403544 )
Norm@50keV : 2.17172E-02 ( -0.00534911 0.00511521 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.77 using 59 PHA bins.
# Reduced chi-squared = 1.031 for 57 degrees of freedom
# Null hypothesis probability = 4.104526e-01
Photon flux (15-150 keV) in 1 sec: 2.49371 ( -0.584943 0.588968 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.50377e-07 ( -5.84147e-08 5.87157e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -0.244 sec. to 0.756 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: 0.799649 ( -1.26953 0.42633 )
Epeak [keV] : 9987.04 ( -9999.35 -9999.35 )
Norm@50keV : 2.25563E-02 ( -0.00487193 0.0449167 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.87 using 59 PHA bins.
# Reduced chi-squared = 1.051 for 56 degrees of freedom
# Null hypothesis probability = 3.710118e-01
Photon flux (15-150 keV) in 1 sec: 2.50369 ( -0.59616 0.57882 ) ph/cm2/s
Energy fluence (15-150 keV) : 2.50509e-07 ( -5.828e-08 5.8155e-08 ) ergs/cm2
Band function
Time interval is from -0.244 sec. to 0.756 sec.
Spectral model in the Band function:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
alpha : 5.00000 ( -5 -5 )
beta : -0.958749 ( -0.528885 0.503118 )
Epeak [keV] : 33.4241 ( -33.4238 43.8672 )
Norm@50keV : 255.568 ( -55.9715 4.44669e+06 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.03 using 59 PHA bins.
# Reduced chi-squared = 1.055 for 55 degrees of freedom
# Null hypothesis probability = 3.643915e-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] : 28.0339 (-8.28226 15.9844)
R^2/D10^2 : 4.41843E-02 (-0.031397 0.0820026)
(R is the radius in km and D10 is the distance to the source in units of 10 kpc)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 64.24 using 59 PHA bins.
# Reduced chi-squared = 1.127 for 57 degrees of freedom
# Null hypothesis probability = 2.379542e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 5.658e-09 2.972e-09
25- 50 3.390e-08 1.615e-08
50-150 1.927e-07 1.023e-07
15-150 2.322e-07 1.091e-07
Thermal bremsstrahlung (OTTB)
Spectral model: thermal bremsstrahlung
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT [keV] : 200.000 ( )
Norm : 10.1508 (-2.43708 2.4369)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 67.44 using 59 PHA bins.
# Reduced chi-squared = 1.183 for 57 degrees of freedom
# Null hypothesis probability = 1.621533e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 2.527e-08 1.508e-08
25- 50 4.862e-08 2.843e-08
50-150 1.066e-07 6.380e-08
15-150 1.805e-07 1.088e-07
Double BB
Spectral model: bbodyrad<1> + bbodyrad<2>
------------------------------------------------------------
Parameters : value Lower 90% Upper 90%
kT1 [keV] : 9.03792 (-3.36972 8.34988)
R1^2/D10^2 : 1.01971 (-0.844017 3.76908)
kT2 [keV] : 76.3116 (-76.6853 -76.6854)
R2^2/D10^2 : 3.01366E-03 (-0.00239286 0.0217298)
------------------------------------------------------------
#Fit statistic : Chi-Squared = 56.73 using 59 PHA bins.
# Reduced chi-squared = 1.031 for 55 degrees of freedom
# Null hypothesis probability = 4.103207e-01
Energy Fluence 90% Error
[keV] [erg/cm2] [erg/cm2]
15- 25 1.761e-08 1.072e-08
25- 50 4.534e-08 2.665e-08
50-150 1.931e-07 1.084e-07
15-150 2.561e-07 1.390e-07
S(25-50 keV) vs. S(50-100 keV) plot
S(25-50 keV) = 3.44e-08
S(50-100 keV) = 9.13e-08
T90 vs. Hardness ratio plot
T90 = 0.64 sec.
Hardness ratio (energy fluence ratio) = 2.65407
Color vs. Color plot
Count Ratio (25-50 keV) / (15-25 keV) = 1.88
Count Ratio (50-100 keV) / (15-25 keV) = 1.98
Mask shadow pattern
IMX = 0.692688935943, IMY = -0.712609536878
TIME vs. PHA plot around the beginning of event data (event_start to event_start+0.64s)
TIME vs. DetID plot around the beginning of event data (event_start to event_start+0.64s)
100 us light curve (15-350 keV; (event_start to event_start+0.64s)
Spacecraft aspect plot
Bright source in the event data image
Event data image of 15-350 keV band
Time interval of the image:
-2.560000 7.350000
# RAcent DECcent POSerr Theta Phi PeakCts SNR AngSep Name
# [deg] [deg] ['] [deg] [deg] [']
135.6950 -40.5227 4.9 49.9 -167.0 0.1799 2.4 7.8 Vela X-1
30.9539 -16.9875 2.7 44.8 45.8 0.5087 4.2 ------ UNKNOWN
130.2664 -26.7020 2.5 57.1 177.3 0.8499 4.5 ------ UNKNOWN
346.0384 -28.0000 2.2 58.4 -7.0 1.0290 5.3 ------ UNKNOWN
317.4998 -65.7885 3.1 45.2 -58.4 0.4955 3.8 ------ UNKNOWN
Webpage updated on:
Wed Jul 15 00:18:50 EDT 2015