Note: The procedures described in this subsection are under testing. Comments are welcome for improvement.
Based on Dulk (1985)'s approximation model, the relation between
the physical variables of emitting region and the emission can be
derived.
(a) From Physical Variables to Emission
Inputs; electron temperature (K), line-of-site component
of magnetic field (G), and volume emission measure (cm)
Outputs; flux density (SFU), circular polarization degree:
IDL> dulk_frfr,te,b_loc,vem,freq,fi,rc CR
If the size of emitting source (by solid angle in unit of sterad) is given
additionally, optical depth is also obtained
IDL> dulk_frfr,te,b_loc,vem,freq,fi,rc,omega,tau CR
(b) From Emission to Physical Variables
Inputs; I-component (RL) and V-component (RL) of flux density (SFU):
Outputs; line-of-sight component of magnetic field (G),
where is volume emission measure, is electron temperature:
IDL> norh_frfr_inv,fi,fv,b_los,vem_over_sqrtte CR
If one of or is assumed, the other is derived:
IDL> norh_frfr_inv,fi,fv,b_los,tein,vem,/assumete CR
IDL> norh_frfr_inv,fi,fv,b_los,vemin,te,/assumevem CR
Adding to this, if the size of emission source is given
(as surface angle. Unit is sterad), optical thickness is derived
IDL> norh_frfr_inv,fi,fv,b_los,tein,vem,/assumete,omega,tau CR
IDL> norh_frfr_inv,fi,fv,b_los,vemin,te,/assumevem,omega,tau CR