相关论文: Circumstellar rings, flat and flaring discs

The radial profiles of stars in disc galaxies are observed to be either purely exponential (Type-I), truncated (Type-II) or anti-truncated (Type-III) exponentials. Controlled formation simulations of isolated galaxies can reproduce all of…

I review theoretical models of star formation and how they apply across the stellar mass spectrum. Several distinct theories are under active study for massive star formation, especially Turbulent Core Accretion, Competitive Accretion and…

We find the forms of the transfer equations for polarized cyclotron radiation in the atmospheres of compact stars, which are simple enough to allow practical implementation and still preserve all important physical effects. We take into…

We present a study of the stellar populations and gas physical conditions in Circumnuclear Star Forming Regions (CNSFRs) based on spectrophotometric data, including the 7000 angstroms to 1 micron spectral range, which is of great interest…

We use a suite of high resolution molecular cloud simulations carried out with the moving mesh code Arepo to explore the nature of star-forming filaments. The simulated filaments are identified and categorised from column density maps in…

We present emission line polarimetry data and modelling relevant to the circumstellar geometry and kinematics around pre-main sequence stars. For a sample of both Herbig Ae/Be stars and T Tauri stars, we find that most show polarization…

A question central to understanding the origin of our solar system is: how do planets form in circumstellar disks around young stars? Because of the complex nature of the physical processes involved, multi-wavelength observations of large…

Using the largest sample of narrow emission line galaxies available so far, we show that their spectral characteristics are correlated with different physical parameters, like the chemical abundances, the morphologies, the masses of the…

In the outskirts of nearby spiral galaxies, star formation is observed in extremely low gas surface densities. Star formation in these regions, where the interstellar medium is dominated by diffuse atomic hydrogen, is difficult to explain…

For much of human history we have wondered how our solar system formed, and whether there are any other planets like ours around other stars. Only in the last 20 years have we had direct evidence for the existence of exoplanets, with the…

The recent detection of planets around very low mass stars raises the question of the formation, composition and potential habitability of these objects. We use planetary system formation models to infer the properties, in particular their…

In this paper, I review how optical spectro-interferometry has become a particularly well suited technique to study the close environment of young stars, by spatially resolving both their IR continuum and line emission regions. I summarize…

We have analyzed the emission line properties in the integrated spectra of 15 normal spiral galaxies. We show that very clear trends appear when plotting relevant emission line ratios or equivalent widths as a function of galaxy spectral…

We have computed the time evolution of bolometric, far-infrared, Halpha line, ultraviolet (both intrinsic and escaping the star forming region) and the nonthermal radio continuum luminosities for continuous and constant star formation. The…

The study of warm molecular gas in the inner region (<10 AU) of circumstellar disks around young stars is of significant importance to understand how planets are forming. This inner zone of disks can now be explored in unprecedented detail…

Star clusters form in dense, hierarchically collapsing gas clouds. Bulk kinetic energy is transformed to turbulence with stars forming from cores fed by filaments. In the most compact regions, stellar feedback is least effective in removing…

This review covers the properties of disks around pre-main--sequence stars. It is at this time in the evolution that planets form, and it is important to understand the properties of these disks to understand planet formation. I discuss…

Using the large emission line galaxy sample from the Sloan Digital Sky Survey we show that Star forming galaxies, Seyferts, and low-ionization nuclear emission-line regions (LINERs) form clearly separated branches on the standard optical…

Newly formed stars are often observed to possess circumstellar disks, from which mass continues to be accreted onto the star and fed into outflowing jets, and which eventually may evolve into dusty debris disks and planetary systems. Recent…

In star forming regions, we can observe different evolutionary stages of various objects and phenomena such as molecular clouds, protostellar jets and outflows, circumstellar disks, and protostars. However, it is difficult to directly…