Astrophysics (Index)About

circumstellar disk

(disk)
(disk or ring shaped accumulation of matter around a star)

A circumstellar disk (in context, just disk) is matter, typically in a ring, collected around a star. It can be composed of gas, dust, planetesimals, or a combination, in orbit around the star. The term protoplanetary disk is often used for the typical case: such a disk around a young star, which constitutes the raw material of future planets. The main asteroid belt around the Sun represents a kind of sparse circumstellar disk.

Excess infrared from a star is evidence of a disk, indicating thermal radiation for something large and cooler than the star. When the disk can be resolved, the material making up the disk and how it varies by radius can be determined from this EMR, which is affected by the dust grain size: the emission of grains is inefficient for wavelengths long in comparison to the grain's diameter.

The term circumbinary disk refers to a circumstellar disk that surrounds both members of a binary star. Under some cases (e.g., some configurations with a third companion), the disk can be tilted substantially from the axis of the stars and the orbit of the binary companion. The terms polar alignment and polar disk refer to a disk that is perpendicular to the orbital plane of the binary companions.

Older stars can also have circumstellar disks, such as debris disks.


(disk type,object type,stars)
Further reading:
https://en.wikipedia.org/wiki/Circumstellar_disk
https://dictionary.obspm.fr/index.php?showAll=1&formSearchTextfield=circumstellar+disk
https://ui.adsabs.harvard.edu/abs/2011MNRAS.413.2767M/abstract
https://ui.adsabs.harvard.edu/abs/2009IAUS..258..111M/abstract

Referenced by pages:
AGN accretion
amateur astronomy
axisymmetric
barrier
Be star
circumplanetary disk
cold mass accretion (CMA)
Coriolis force
corotation resonance
corotation torque
dead zone
debris disk
disk
DM Tau
epicycle
extra-solar planet
GG Tau
gravitational instability (GI)
Hall effect
heating
infrared excess (IRX)
Kepler radius
Keplerian disk
LDN 1527 (L1527)
libration
Lindblad resonance
Lindblad torque
Lyot coronagraph (CLC)
mass transport
Maxwell-Boltzmann distribution
nebular hypothesis
planet formation
planetary system
Poynting-Robertson effect
protoplanetary disk (PPD)
radiation pressure
Roche limit
Rossby number (Ro)
shell star (sh)
spiral arm
spiral density wave
sublimation
surface density (Σ)
thin disk
transitional disk
young stellar object (YSO)

Index