Related papers: Modelling the H Lyman lines in evolved late-type s…
I describe recent progress in terms of 3D hydrodynamical model atmospheres and 3D line formation and their applications to stellar abundance analyses of late-type stars. Such 3D studies remove the free parameters inherent in classical 1D…
Uncertainties in the radial distribution of galaxies, $\boldsymbol{n}(\boldsymbol{z})$, are one of the major contributions to the error budget of early Stage-IV galaxy survey analyses of weak gravitational lensing, galaxy clustering and…
We describe the addition of Lyman-alpha resonant line transfer to our dust continuum radiation transfer code SKIRT, verifying our implementation with published results for spherical problems and using some self-designed three-dimensional…
In this paper, we provide a physical model for the origin of variations in the shapes and bump strengths of dust attenuation laws in galaxies by combining a large suite of cosmological "zoom-in" galaxy formation simulations with 3D Monte…
A numerical code for solving various Lyman alpha (Lya) radiative transfer (RT) problems is presented. The code is suitable for an arbitrary, three-dimensional distribution of Lya emissivity, gas temperature, density, and velocity field.…
Hydrogen recombination lines (HRLs) are valuable diagnostics of the physical conditions in ionized regions around high-mass stars. Understanding their broadening mechanisms and intensity trends can provide insights into the densities,…
Present grids of stellar atmosphere models are the workhorses in interpreting stellar observations, and determining their fundamental parameters. These models rely on greatly simplified models of convection, however, lending less predictive…
Realistic stellar atmospheric models of two typical metal-poor giant stars in Omega Centauri that include a chromosphere influence the formation of optical lines of Oxygen I: the forbidden lines (630nm, 636nm) and the infrared triplet…
The Lyman-alpha emission line is the strongest feature in the spectrum of most high redshift galaxies, and is typically observed as being highly asymmetric due to galactic outflows. Quantifying this asymmetry is challenging. Here, we…
In the course of our ongoing search for serendipitous high-redshift Lyman alpha (LyA) Emissionin deep archival Keck spectra, we discovered two very high equivalent width (W_{obs} ~ 450A, 2-sigma) LyA emission line candidates at z ~3 in a…
We perform non-LTE calculations of lithium in late-type stars for a wide range of stellar parameters, including quantum mechanical cross-sections for collisions with neutral hydrogen and the negative hydrogen ion. Non-LTE abundance…
Stellar models with masses ranging from 0.5 to $1.3~M_\odot$ were constructed in order to compare to young cluster observations of Li and of rotation velocities. The amount of Li depletion in cool stars is sensitive to the amount of…
We calculate models of extended stellar atmospheres with a temperature in the range of 12000-40000K and a mass loss rate of $10^{-6}-10^{-4} M_{\odot}$ yr$^{-1}$. A large number of objects with emission spectra, such as luminous blue…
We present our analysis of UV attenuation by internal dust of a large sample (N=906 galaxies) of Lyman Break Galaxies (LBGs). Using spectral energy distributions (SEDs) from the P\'EGASE galaxy spectral evolution model we apply dust…
We highlight and discuss the importance of accounting for nebular emission in the SEDs of high redshift galaxies, as lines and continuum emission can contribute significantly or subtly to broad-band photometry. Physical parameters such as…
With the Multi Unit Spectroscopic Explorer (MUSE), it is now possible to detect spatially extended Lyman alpha emission from individual faint (M_UV ~ -18) galaxies at redshifts, 3 < z < 6, tracing gas out to circum-galactic scales…
Models of radiation transport in stellar atmospheres are the hinge of modern astrophysics. Our knowledge of stars, stellar populations, and galaxies is only as good as the theoretical models, which are used for the interpretation of their…
We revised the treatment of interstellar dust in the KOSMA-\tau\ PDR model code to achieve a consistent description of the dust-related physics in the code. The detailed knowledge of the dust properties is then used to compute the dust…
I provide an overview about star-forming galaxies at high redshift and their physical properties. Starting from the populations of Ly-$\alpha$ emitters and Lyman break galaxies, I summarize their common features and distinction. Then I…
We provide a brief overview of the modelling of the atmospheres of red giant stars with the 3D radiation-hydrodynamics code CO5BOLD. We emphasize aspects where 3D modelling provides additional insight beyond standard hydrostatic 1D models,…