Astronomy   View all facts   Glossary   Help

physical object > natural object > celestial body > star > giant > heavy-metal star

heavy-metal star
subject			fact

heavy-metal star	has definition A class of peculiar giant that includes the Ba II stars and the S stars.
	is a kind of giant
giant	has luminosity class III
star	has star surface temperature
	has spectral type
	has V magnitude
	has B magnitude
	has U magnitude
	has position on celestial sphere from the point of view of Earth
	has parallax from the point of view of Earth's orbit
	has proper motion
	has radiation at surface which is diffused out from the hotter core
	has energy source gravitational contraction and or fusion
	has energy production which takes place primarily within the core
	has surface density which depends on luminosity class
	has surface temperature greater than 1000 Kelvin
	has apparent magnitude
	has absolute magnitude
	has age
	has catalog star catalog
	has material hydrogen, helium
	has velocity determined from proper motion and radial velocity
	has mass greater than 0.08 the sun's mass
celestial body	has spectra
physical object	has location or center of gravity
	has angular momentum
	has momentum
	has temperature
	has volume
	has extent

Kinds of heavy-metal star :

• barium star (1 kind, 8 facts) (Ba star, Ba II star) - Late type giants (G2 to K4) with a very strong BaII 4554 line. Main sequence stars with strong BaII lines have also been discovered recently., Peculiar low-velocity, strong lined red-giant stars of spectral types G, K, and M, with abnormally large abundances of heavy s-process (but not r-process) elements. They are usually regarded as old disk stars of ~ 1-2 M_sun.
• S star (1 kind, 8 facts) - Red-giant stars of spectral type S are similar to M stars except that the dominant oxides are those of the metals of the fifth period (Zr, Y, etc.) instead of the third (Ti, Sc, V). They also have strong CN bands and contain spectral lines of lithium and technetium. Pure S stars are those in which ZrO bands are very strong and TiO bands are either absent or only barely detectable. Almost all S stars are LPVs. (S1,0. The number following the comma is an abundance parameter.) Hopkins, J. 1976 Glossary of Astronomy and Astrophysics, University of Chicago Press, Late type giants (K5 to M) showing distinct bands of ZrO. Jaschek, C., Jaschek, M. 1995 The Behavior of Chemical Elements in Stars, Cambridge University Press, Red-giant star of spectral type S are similar to M stars except that the dominant oxides are those of the metals of the fifth period (Zr, Y, etc.) instead of the third (Ti, Sc, V). They also have strong CN bands and contain spectral lines of lithium and technetium. Pure S stars are those in which ZrO bands are very strong and TiO bands are either absent or only barely detectable. Almost all S stars are LPVs. (S1,0. The number following the comma is an abundance parameter.), Late type giant (K5 to M) showing distinct bands of ZrO.

Next giant: HR 4247    Up: giant    Previous giant: Gamma Sagittae