Bpow - Broken Power Law
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- | There are four free parameters that are allowed to vary when using Bpow to fit the non-thermal portion of a spectrum. In practice, a[1], the negative power law index below the break energy is set to -1.5 and fixed. | + | There are four free parameters that are allowed to vary when using Bpow to fit the non-thermal portion of a spectrum. In practice, a[1], the negative power law index below the break energy is set to -1.5 and fixed. |
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+ | [[Image:bpow.jpg|center|thumb|600px|A broken power law fit to the count flux spectrum (top panel) and the photon flux spectrum (bottom panel)]] | ||
[[Category:Software]] | [[Category:Software]] |
Revision as of 19:22, 14 July 2009
Contents |
Broken Power Law
Introduction
The broken power law component models the non-thermal portion of the spectrum for a selected time interval during a flare. It fits the spectrum above approximately 25keV with a broken power law, normalized to the value of the count flux at 50keV.
Parameters
- a[0] - normalization at epivot
- a[1] - negative power law index below break
- a[2] - break energy (keV)
- a[3] - negative power law index above break
Fitting with Bpow
There are four free parameters that are allowed to vary when using Bpow to fit the non-thermal portion of a spectrum. In practice, a[1], the negative power law index below the break energy is set to -1.5 and fixed.