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diskpbb: accretion disk, power-law dependence for T(r)

A multiple blackbody disk model where local disk temperature T(r) is proportional to $r^{-p}$, where $p$ is a free parameter. The standard disk model, diskbb, is recovered if $p = 0.75$. If radial advection is important then $p < 0.75$. See the discussion and examples in, e.g., Mineshige et al. (1994); Hirano et al. (1995); Watarai et al. (2000); Kubota and Makishima (2004); Kubota et al. (2005).

par1 Tin, temperature at inner disk radius (keV)
par2 p, exponent of the radial dependence of the disk temperature
norm $(R_{in}/D_{10})^2 \cos\theta$, where where $R_{in}$ is “an apparent” inner disk radius in km, $D_{10}$ the distance to the source in units of 10 kpc, and $\theta$ the angle of the disk ($\theta
= 0$ is face-on). On the correction factor between the apparent inner disk radius and the realistic radius, see e.g., Kubota et al. (1998).