Book contents
- Frontmatter
- Contents
- Preface
- Names and addresses of participants
- Conference photograph
- Spiral waves in Saturn's rings
- Structure of the Uranian rings
- Planetary rings: theory
- Simulations of light scattering in planetary rings
- Accretion discs around young stellar objects and the proto-Sun
- The β Pictoris disc: a planetary rather than a protoplanetary one
- Optical polarimetry and thermal imaging of the disc around β Pictoris
- Observations of discs around protostars and young stars
- VLA observations of ammonia toward molecular outflow sources
- Derivation of the physical properties of molecular discs by an MEM method
- Masers associated with discs around young stars
- The nature of polarisation discs around young stars
- The correlation between the main parameters of the interstellar gas (including Salpeter's spectrum of masses) as a result of the development of turbulent Rossby waves
- Discs in cataclysmic variables and X-ray binaries
- A disc instability model for soft X-ray transients containing black holes
- X-ray variability from the accretion disc of NGC 5548
- Viscously heated coronae and winds around accretion discs
- Optical emission line profiles of symbiotic stars
- The effect of formation of Fell in winds confined to discs for luminous stars
- Observational evidence for accretion discs in active galactic nuclei
- The fuelling of active galactic nuclei by non-axisymmetric instabilities
- The circum-nuclear disc in the Galactic centre
- Non-axisymmetric instabilities in thin self-gravitating differentially rotating gaseous discs
- Non-linear evolution of non-axisymmetric perturbations in thin self-gravitating gaseous discs
- Eccentric gravitational instabilities in nearly Keplerian discs
- Gravity mode instabilities in accretion tori
- The stability of viscous supersonic shear flows – critical Reynolds numbers and their implications for accretion discs
- Asymptotic analysis of overstable convective modes of uniformly rotating stars
- Polytropic models in very rapid rotation
- Distribution and kinematics of gas in galaxy discs
- Are the smallest galaxies optically invisible?
- Can we understand the constancy of rotation curves?
- How well do we know the surface density of the Galactic disc?
- On the heating of the Galactic disc
- The bulge-disc interaction in galactic centres
- Dynamics of the large-scale disc in NGC 1068
- The flow of gas in barred galaxies
- The warped dust lane in A1029-459
- Structure and evolution of dissipative non-planar galactic discs
- Non-axisymmetric magnetic fields in turbulent gas discs
- Non-axisymmetric disturbances in galactic discs
- Spiral instabilities in N-body simulations
- Long-lived spiral waves in N-body simulations
- Overstable modes in stellar disc systems
- Galactic seismological approach to the spiral galaxy NGC 3198
- Characteristics of bars from 3-D simulations
- Spirals and bars in linear theory
- Stellar hydrodynamical solutions for Eddington discs
- Theory of gradient instabilities of the gaseous Galactic disc and rotating shallow water
- Stability criteria for gravitating discs
- Stability of two-component galactic discs
- The smoothed particle hydrodynamics of galactic discs
- Tidal triggering of active disc galaxies by rich clusters
- The formation of spiral arms in early stages of galaxy interaction
- Formation of leading spiral arms in retrograde galaxy encounters
- The influence of galaxy interactions on stellar bars
- Disc galaxies – work in progress in Gothenburg
- Motion of a satellite in a disc potential
- Observer's summary
- Common processes and problems in disc dynamics
- Citation index
- Index of authors
- Subject index
Accretion discs around young stellar objects and the proto-Sun
Published online by Cambridge University Press: 06 July 2010
- Frontmatter
- Contents
- Preface
- Names and addresses of participants
- Conference photograph
- Spiral waves in Saturn's rings
- Structure of the Uranian rings
- Planetary rings: theory
- Simulations of light scattering in planetary rings
- Accretion discs around young stellar objects and the proto-Sun
- The β Pictoris disc: a planetary rather than a protoplanetary one
- Optical polarimetry and thermal imaging of the disc around β Pictoris
- Observations of discs around protostars and young stars
- VLA observations of ammonia toward molecular outflow sources
- Derivation of the physical properties of molecular discs by an MEM method
- Masers associated with discs around young stars
- The nature of polarisation discs around young stars
- The correlation between the main parameters of the interstellar gas (including Salpeter's spectrum of masses) as a result of the development of turbulent Rossby waves
- Discs in cataclysmic variables and X-ray binaries
- A disc instability model for soft X-ray transients containing black holes
- X-ray variability from the accretion disc of NGC 5548
- Viscously heated coronae and winds around accretion discs
- Optical emission line profiles of symbiotic stars
- The effect of formation of Fell in winds confined to discs for luminous stars
- Observational evidence for accretion discs in active galactic nuclei
- The fuelling of active galactic nuclei by non-axisymmetric instabilities
- The circum-nuclear disc in the Galactic centre
- Non-axisymmetric instabilities in thin self-gravitating differentially rotating gaseous discs
- Non-linear evolution of non-axisymmetric perturbations in thin self-gravitating gaseous discs
- Eccentric gravitational instabilities in nearly Keplerian discs
- Gravity mode instabilities in accretion tori
- The stability of viscous supersonic shear flows – critical Reynolds numbers and their implications for accretion discs
- Asymptotic analysis of overstable convective modes of uniformly rotating stars
- Polytropic models in very rapid rotation
- Distribution and kinematics of gas in galaxy discs
- Are the smallest galaxies optically invisible?
- Can we understand the constancy of rotation curves?
- How well do we know the surface density of the Galactic disc?
- On the heating of the Galactic disc
- The bulge-disc interaction in galactic centres
- Dynamics of the large-scale disc in NGC 1068
- The flow of gas in barred galaxies
- The warped dust lane in A1029-459
- Structure and evolution of dissipative non-planar galactic discs
- Non-axisymmetric magnetic fields in turbulent gas discs
- Non-axisymmetric disturbances in galactic discs
- Spiral instabilities in N-body simulations
- Long-lived spiral waves in N-body simulations
- Overstable modes in stellar disc systems
- Galactic seismological approach to the spiral galaxy NGC 3198
- Characteristics of bars from 3-D simulations
- Spirals and bars in linear theory
- Stellar hydrodynamical solutions for Eddington discs
- Theory of gradient instabilities of the gaseous Galactic disc and rotating shallow water
- Stability criteria for gravitating discs
- Stability of two-component galactic discs
- The smoothed particle hydrodynamics of galactic discs
- Tidal triggering of active disc galaxies by rich clusters
- The formation of spiral arms in early stages of galaxy interaction
- Formation of leading spiral arms in retrograde galaxy encounters
- The influence of galaxy interactions on stellar bars
- Disc galaxies – work in progress in Gothenburg
- Motion of a satellite in a disc potential
- Observer's summary
- Common processes and problems in disc dynamics
- Citation index
- Index of authors
- Subject index
Summary
Abstract Observed infrared and ultraviolet excesses have widely been interpreted as signatures for accretion discs around young stellar objects. Analyses of the observed properties of these discs are important for the investigation of star formation as well as the dynamics of the protoplanetary disc out of which the solar system was formed. Accretion disc theories suggest that evolution of protoplanetary discs is determined by the efficiency of angular momentum transport. During the formation stages, the disc dynamics are regulated by mixing of infalling material and disc gas. In the outermost regions of the disc, self-gravity may promote the growth of non-axisymmetric perturbations which can transfer angular momentum outwards. After infall has ceased, convectively driven turbulence can redistribute angular momentum with an evolutionary time-scale of the order 105−6 yr. Convection in protoplanetary discs may eventually be stabilized by surface heating as the disc material is depleted. Once the grains in the disc have settled to the midplane region, the disc can neither generate its own energy through viscous dissipation nor reflect radiation from the central star. Consequently, the infrared excess vanishes and the young stellar objects become “naked T Tauri stars.” Protoplanetary formation modifies the structure and evolution of the disc when giant protoplanets acquire sufficient mass to truncate the disc. In this case, a protoplanet's tidal torque opens up a gap in disc. Gap formation also leads to the termination of protoplanetary growth by accretion. The condition for a proto-Jupiter to acquire its present mass implies that the viscous evolution time-scale for the disc is of the order 105−6 yr which is comparable to the age of typical T Tauri stars with circumstellar protoplanetary discs.
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- Dynamics of Astrophysical Discs , pp. 27 - 42Publisher: Cambridge University PressPrint publication year: 1989
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