activity
19972019
most citedDiagnostics of irradiated dense gas in galaxy nuclei. II. A grid of XDR and PDR models

390 citations · 2.4k across the 41 of their papers we have counts for

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Showing 2005 · astro-phShow all

6 papers · 2 filters

astro-ph2005

Lyman Alpha Radiation From Collapsing Protogalaxies II: Observational Evidence for Gas Infall

Mark Dijkstra, Zoltan Haiman, Marco Spaans

We model the spectra and surface brightness distributions for the Lyman alpha (Lya) radiation expected from protogalaxies that are caught in the early stages of their assembly. We…

astro-ph2005

Lyman Alpha Radiation From Collapsing Protogalaxies I: Characteristics of the Emergent Spectrum

Mark Dijkstra, Zoltan Haiman, Marco Spaans

We present Monte Carlo calculations of Lyman alpha (Lya) radiative transfer through collapsing gas clouds, representing proto-galaxies that are caught in the process of their assem…

astro-ph2005

Gravoturbulent Star Formation: Effects of the Equation of State on Stellar Masses

R. S. Klessen, M. Spaans, A. -K. Jappsen

Stars form by gravoturbulent fragmentation of interstellar gas clouds. The supersonic turbulence ubiquitously observed in Galactic molecular gas generates strong density fluctuatio…

astro-ph2005

The excitation of water in the S140 photon dominated region

D. R. Poelman, M. Spaans

We consider the excitation of water in the Photon Dominated Region (PDR). With the use of a three-dimensional escape probability method we compute the level populations of ortho- a…

astro-ph2005

Diagnostics of irradiated gas in galaxy nuclei. I: A Far-ultraviolet and X-ray dominated region code

Rowin Meijerink, Marco Spaans

We present a far-ultraviolet (PDR) and an X-ray dominated region (XDR) code. We include and discuss thermal and chemical processes that pertain to irradiated gas. An elaborate chem…

astro-ph2005

The Impact of Gravitational Redshift on Systemic Water Maser Emission in NGC 4258

M. Spaans

NGC 4258 is well known for its 22 GHz water maser features that appear to reside in a thin Keplerian disk orbiting at R_0=0.13 pc. The influence of gravitational redshift on the le…