PWN

class gammapy.astro.source.PWN(pulsar=<gammapy.astro.source.pulsar.Pulsar object>, snr=<gammapy.astro.source.snr.SNRTrueloveMcKee object>, eta_e=0.999, eta_B=0.001, morphology='Gaussian2D', age=None)

Bases: object

Simple pulsar wind nebula (PWN) evolution model.

Parameters:

pulsar : Pulsar

Pulsar model instance.

snr : SNRTrueloveMcKee

SNR model instance

eta_e : float

Fraction of energy going into electrons.

eta_B : float

Fraction of energy going into magnetic fields.

age : Quantity

Age of the PWN.

morphology : str

Morphology model of the PWN

Methods Summary

luminosity_tev([t, fraction])	Simple luminosity evolution model.
magnetic_field([t])	Estimate of the magnetic field inside the PWN.
radius([t])	Radius of the PWN at age t.

Methods Documentation

luminosity_tev(t=None, fraction=0.1)

Simple luminosity evolution model.

Assumes that the luminosity is just a fraction of the total energy content of the pulsar. No cooling is considered and therefore the estimate is very bad.

Parameters:

t : Quantity

Time after birth of the SNR.

magnetic_field(t=None)

Estimate of the magnetic field inside the PWN.

By assuming that a certain fraction of the spin down energy is converted to magnetic field energy an estimation of the magnetic field can be derived.

Parameters:

t : Quantity

Time after birth of the SNR.

radius(t=None)

Radius of the PWN at age t.

Reference: http://adsabs.harvard.edu/abs/2006ARA%26A..44…17G (Formula 8).

Parameters:

t : Quantity

Time after birth of the SNR.

Notes

During the free expansion phase the radius of the PWN evolves like:

\[R_{PWN}(t) = 1.44\text{pc}\left(\frac{E_{SN}^3\dot{E}_0^2} {M_{ej}^5}\right)^{1/10}t^{6/5}\]

After the collision with the reverse shock of the SNR, the radius is assumed to be constant (See radius_reverse_shock)