T-Tauri star
(TTS)
(type of variable pre-main-sequence star)
A T-Tauri star (TTS) is a type of variable star
showing substantial irregular day-to-day variation,
and often showing certain specific emission lines
(H-alpha,
Ca II,
Fe,
O I,
Si II)
and often a lithium absorption line.
They are judged to be very young (pre-main-sequence) dwarfs of about
2.5 solar masses or less. They often have protoplanetary disks
and often are in the vicinity of molecular clouds.
They often have strong stellar winds and/or jets,
both ascribed to accretion from the disk.
Their energy/luminosity is presumed to be from
gravitation (Kelvin-Helmholtz mechanism)
rather than fusion, the latter not yet triggered.
They generally have a short rotation period in the range of 1-12 days.
Some subtypes:
- CTTS (classical T-Tauri star) extensive disk indicated by strong (broad) emission lines.
- WTTS (weak-line T-Tauri star) weak or non-existent signs of a disk.
- NTTS (naked T-Tauri star) sometimes used synonymously with WTTS, but the two terms are sometimes used to distinguish between "weak" and "non-existent".
The name comes from T Tauri, a star first discerned to have
these characteristics, which serves as a prototype/example.
(star type,variable,stellar evolution)
Further reading:
https://en.wikipedia.org/wiki/T_Tauri_star
http://www.astro.sunysb.edu/fwalter/TMP/ss2.ppt.pdf
https://astronomy.swin.edu.au/cosmos/t/T+Tauri+Stars
http://hyperphysics.phy-astr.gsu.edu/hbase/Starlog/ttauri.html
https://phys.org/news/2016-06-t-tauri-stars.html
https://ui.adsabs.harvard.edu/abs/1945ApJ...102..168J/abstract
Referenced by pages:
DM Tau
DQ Tau
emission-line object
emission-line star
GG Tau
Herbig AeBe star (HAeBe)
HL Tau
Lick Observatory Calcium Line Survey (LkCl)
PDS 70
Pico dos Dias Survey (PDS)
pre-main-sequence star (PMS)
protoplanetary disk (PPD)
protostar
rare designator prefixes
RXJ1615
stellar age determination
stellar association
stellar evolution
T association
T Tauri
T-type star (T)
TW Hydrae (TW Hya)
TW Hydrae association (TWA)
variable star
Index