HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.

Search:

[Advanced Search]



Self-irradiated funnel

NOTE: This model is now in the Xspec release and this page is superceded by the Xspec manual

The multiblackbody "Self-IrRdaiated Funnel" model is designed to model optically-thick outflow-dominated accretion. The basic idea is simple: you just assume a lot of matter, angular momentum and energy emerges in a limited volume. Momentum conservation leads to non-sphericity of the flow that has subsequently conical (funnel-like) shape. The model calculates temperature distribution at the funnel walls (taking into account irradiation by iterative process) and the outer photosphere. We also assume that inside the cone there is a deep pseudo-photosphere. Relativistic boosts are taken into account for high velocities. For a comprehensive description of the physical model, see: Abolmasov, P., Karpov, S. and Kotani, T. PASJ, 61, 2, 213.

par1 = tin, inner temperature (at the inner, inside-the-funnel photosphere).
par2 = rin, inner (inside-the-funnel photosphere) radius in "spherisation radius" units (the latter is defined as 3 Κ Mdot / Ωf c).
par3 = rout, outer photosphere radius in "spherisation radius" units.
par4 = theta, half-opening angle of the cone.
par5 = incl, inclination angle of the funnel. Affects mainly self-occultation and relativistic boost effects.
par6 = valpha, velocity law exponent, v goes as rvalpha.
par7 = gamma, adiabate index. It affects the inner, hotter parts of the flow, therefore we set is to 4/3 by default.
par8 = mdot, mass ejection rate in Eddington (critical) units.
par9 = irrad, number of iterations for irradiation.

The source code file required is sirf.cpp with the parameter information in lmodel_sirf.dat.

Keith Arnaud, Lab. for High Energy Astrophysics, NASA/Goddard Space Flight Center

Xspec Xspec Home Page

HEASARC Home | Observatories | Archive | Calibration | Software | Tools | Students/Teachers/Public
Last modified: Tuesday, 14-Feb-2023 16:42:01 EST

HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.