相关论文: Peter Pan Discs: finding Neverland's parameters

The extreme outer regions of disk galaxies, lying at or beyond the classical optical radius defined by R25, present an opportunity to study star formation and chemical evolution under unique physical conditions, possibly reminscent of those…

We explore how measurements of protoplanetary disc masses and accretion rates provided by surveys of star forming regions can be analysed via the dimensionless accretion parameter, which we define as the product of the accretion rate and…

Self-gravitating protostellar discs are unstable to fragmentation if the gas can cool on a time scale that is short compared to the orbital period. We use a combination of hydrodynamic simulations and N-body orbit integrations to study the…

The formation of gas-giant planets within the lifetime of a protoplanetary disk is challenging especially far from a star. A promising model for the rapid formation of giant-planet cores is pebble accretion in which gas drag during…

Recent observations have unveiled a population of pulsars with spin periods of a few minutes to hours that lie beyond the traditional ``death line.'' If they originate from neutron stars (NSs), the existence of such ultra-long period…

The dispersal of the circumstellar discs of dust and gas surrounding young low- mass stars has important implications for the formation of planetary systems. Photo- evaporation from energetic radiation from the central object is thought to…

This manuscript investigates the impact of key dust evolution parameters on dust retention and trapping in protoplanetary discs. Using models with and without pressure bumps, combined with radiative transfer simulations, images of the dust…

Keplerian accretion discs around massive black holes (MBHs) are gravitationally unstable beyond a few hundredths of parsec and should collapse to form stars. Indeed an accretion/star formation episode took place a few millions years ago in…

Disc fragmentation provides an important mechanism for producing low mass stars in prestellar cores. Here, we describe Smoothed Particle Hydrodynamics simulations which show how populations of prestellar cores evolve into stars. We find the…

Young accreting planetary-mass objects are thought to draw material from a circumplanetary disk (CPD) composed of gas and dust. While the gas within the disk is expected to disperse within the first million years, strong accretion has…

We use time-dependent, one-dimensional disc models to investigate the evolution of protostellar discs that form through the collapse of molecular cloud cores and in which the primary transport mechanism is self-gravity. We assume that these…

Aims: We investigate the evolution of protoplanetary discs (PPDs hereafter) with magnetically driven disc winds and viscous heating. Methods: We consider an initially massive disc with ~0.1 Msun to track the evolution from the early stage…

(Abridged) We consider the properties of protoplanetary discs that are undergoing inside-out clearing by photoevaporation. In particular, we aim to characterise the conditions under which a protoplanetary disc may undergo `thermal…

Several planets have recently been discovered around old metal-poor stars, implying that these planets are also old, formed in the early Universe. The canonical theory suggests that the conditions for their formation could not have existed…

Protostars grow in mass by accreting material through their discs, and this accretion is initially their main source of luminosity. The resulting radiative feedback heats the environments of young protostars, and may thereby suppress…

Measured disk masses seem to be too low to form the observed population of planetary systems. In this context, we develop a population synthesis code in the pebble accretion scenario, to analyse the disk mass dependence on planet formation…

Many theoretical studies have shown that external photoevaporation from massive stars can severely truncate, or destroy altogether, the gaseous protoplanetary discs around young stars. In tandem, several observational studies report a…

I attempt to summarize our knowledge of planet formation in evolving protoplanetary discs. I first review the physics of disc evolution and dispersal. For most of the disc lifetime evolution is driven by accretion and photoevaporation, and…

Observations of massive stars within the central parsec of the Galaxy show that, while most stars orbit within a well-defined disc, a significant fraction have large eccentricities and / or inclinations with respect to the disc plane. Here,…

Investigations of stellar encounters in cluster environments have demonstrated their potential influence on the mass and angular momentum of protoplanetary discs around young stars. In this study it is investigated in how far the initial…