Related papers: Variability in the Assembly of Protostellar System…
The early evolution of protostellar disks with metallicities in the $Z=1.0-0.01~Z_\odot$ range was studied with a particular emphasis on the strength of gravitational instability and the nature of protostellar accretion in low-metallicity…
The study of protoplanetary disc evolution and planet formation has mainly concentrated on solar (and low) mass stars since they host the majority of the confirmed exoplanets. Nevertheless, the numerous planets found orbiting stars up to…
Since the 1990's, protoplanetary disks and planetary disks have been intensively observed from the optical to the millimetre wavelength and many models have been developed to investigate their gas and dust properties and dynamics. These…
This tutorial is an introduction to observational studies of dust transport and evolution in protoplanetary disks. Spatially resolved observations of disks at multiple wavelengths can allow to infer the distribution of various dust grains…
Over the past decade, advancement of observational capabilities, specifically the Atacama Large Millimeter/submillimeter Array (ALMA) and SPHERE instrument, alongside theoretical innovations like pebble accretion, have reshaped our…
Variable accretion in young stellar objects reveals itself photometrically and spectroscopically over a continuum of timescales and amplitudes. Most dramatic are the large outbursts (e.g., FU Ori, V1647 Ori, and EX Lup type events), but…
A detailed understanding of the physics of star and planet formation requires study of individual objects as well as statistical assessment of global properties and evolutionary trends. Observational investigations of circumstellar material…
We perform calculations of our one-dimensional, two-zone disk model to study the long-term evolution of the circumstellar disk. In particular, we adopt published photoevaporation prescriptions and examine whether the photoevaporative loss…
The formation and evolution of the circumstellar disk in unmagnetized molecular clouds is investigated using three-dimensional hydrodynamic simulations from the prestellar core until the end of the main accretion phase. In collapsing…
Dust constitutes only about one percent of the mass of circumstellar disks, yet it is of crucial importance for the modeling of planet formation, disk chemistry, radiative transfer and observations. The initial growth of dust from…
Mass accretion onto (proto-)stars at high accretion rates > 10^-4 M_sun/yr is expected in massive star formation. We study the evolution of massive protostars at such high rates by numerically solving the stellar structure equations. In…
The origin of disks surrounding young stars has direct implications for our understanding of the formation of planetary systems. In the interstellar clouds from which star form, angular momentum is regulated by magnetic fields, preventing…
Using zoom-simulations carried out with the adaptive mesh-refinement code RAMSES with a dynamic range of up to $2^{27} \approx 1.34 \times 10^8$ we investigate the accretion profiles around six stars embedded in different environments…
We investigate the formation of protoplanetary disks around nine solar mass stars formed in the context of a (40 pc)$^3$ Giant Molecular Cloud model, using RAMSES adaptive-mesh refinement simulations extending over a scale range of about 4…
The radial drift and diffusion of dust particles in protoplanetary disks affect both the opacity and temperature of such disks as well as the location and timing of planetesimal formation. In this paper, we present results of numerical…
The disks that orbit young stars are the essential conduits and reservoirs of material for star and planet formation. Their structures, meaning the spatial variations of the disk physical conditions, reflect the underlying mechanisms that…
Context. Protoplanetary discs are the birthplaces of planets. Recent studies highlight the role of stellar mass sampling in determining disc lifetimes from the observed fraction of stars with discs. Low-mass stars tend to host longer-lived…
We present a theoretical model for primordial star formation. First we describe the structure of the initial gas cores as virialized, quasi-hydrostatic objects in accord with recent high resolution numerical studies. The accretion rate can…
Identifying the processes that determine strength, duration and variability of protostellar mass growth is a fundamental ingredient of any theory of star formation. I discuss protostellar mass accretion rates dM/dt from numerical models…
In the standard picture for low-mass star formation, a dense molecular cloud undergoes gravitational collapse to form a protostellar system consisting of a new central star, a circumstellar disk, and a surrounding envelope of remaining…