papers

Publications (9)

astro-ph.GA2024

Luminosity distance and extinction by submicrometer-sized grains

Ralf Siebenmorgen, Frank Heymann, Rolf Chini

The distance to the stars is a fundamental parameter, which is determined via two primary methods - parallax and luminosity. While the parallax is a direct trigonometric method, th…

astro-ph.GA2015

Self-consistent 2-phase AGN torus models: SED library for observers

Ralf Siebenmorgen, Frank Heymann, Andreas Efstathiou

We assume that dust near active galactic nuclei (AGN) is distributed in a torus-like geometry, which may be described by a clumpy medium or a homogeneous disk or as a combination o…

astro-ph.SR2012

Shadows, gaps, and ring-like structures in protoplanetary disks

Ralf Siebenmorgen, Frank Heymann

We study the structure of passively heated disks around T Tauri and Herbig Ae stars, and present a vectorized Monte Carlo dust radiative transfer model of protoplanetary disks. The…

astro-ph.SR2012

PAH in three dimensional Monte Carlo radiativtive transfer

Ralf Siebenmorgen, Frank Heymann, Endrik Krügel

We present a Monte Carlo (MC) radiative transfer code for complex three dimensional dust distributions and include transiently heated PAH. The correctness of the code is confirmed…

astro-ph.SR2012

PAHs in protoplanetary disks: emission and X-ray destruction

Ralf Siebenmorgen, Frank Heymann

We study the PAH emission from protoplanetary disks. First, we discuss the dependence of the PAH band ratios on the hardness of the absorbed photons and the temperature of the star…

astro-ph.CO2011

The processing of radiation by dust in galaxies

Ralf Siebenmorgen, Frank Heymann

Optical/UV photons and even harder radiation components in galaxies are absorbed and scattered by dust and re-emitted at infrared wavelengths. For a better understanding of the obs…