Stellar Evolution in AGN Disks

geometrically thin disks in AGN

We suggest that magnetic fields in the accretion disks of AGN reach into the coronae above and have a profound effect on the mass flow rate in the corona. This strongly affects the location where the accretion flow changes from a geometrically thin disk to a pure vertically extended coronal or advection-dominated accretion flow (ADAF). We show that this can explain the different disk truncation...

Evolution of Dusty Disks in Nearby Young Stellar Groups

Given their proximity and age differences, nearby groups of young stars are valuable laboratories for investigations of disk evolution and diversity. The estimated 10-Myr age of groups like the TW Hydrae Association provides a strong constraint on disk evolution timescales and fills a significant gap in the age sequence between 1-Myr-old T Tauri stars in molecular clouds and 50-Myr-old nearby o...

Truncations in stellar disks

Stellar disks in edge-on spiral galaxies have been known to have –at least in some cases– rather sharp edges or truncations (van der Kruit 1979). These are obvious when examining isophote maps in which the outer isophotes in the radial direction come suddenly much closer together (see Fig. 1). The reality of the truncations can also be inferred from the fact that the fainter isophotes of bright...

Evolution of Agn and Stellar Formation through Radio Surveys

The change in the slope of the radio source counts suggests the emergence of a new population of radio galaxies at mJy and sub-mJy levels. Our understanding of such faint radio sources has advanced over the last decade through increasingly sensitive radio surveys and follow-up works at optical wavelength. The sub–mJy population seems to include both star forming galaxies and classical (AGN-powe...

Young Stellar Disks as the Sites of Planetary Evolution