Structure and Evolution of Stars Lecture 4
2a2
m1
r1
r2
2a1
Centre of Mass
m2
ions in the spectroscopic binary Herbig Ae star RS Cha
not osof ae,
lar saennised dif1). not ul72; nal in-
Table 4.1. Parameters of Alecian et al., 2005, [2] Clausen & Nordstrom, 1980. Parameter M/M! R/R! T eff [K] log(L/L! ) log(g) [cm s−2 ] v sin i [km s−1 ] Porb [d] i [deg] [Fe/H]
RS Cha. References: Ribas et al., 2000,
Primary Secondary 1.89±0.01 1.87±0.01 2.15±0.06 1.87±0.01 7638±76 7228±72 1.15±0.09 1.13±0.09 4.05±0.06 3.96±0.06 64±6 70±6 1.67 83.4±0.3 0.17±0.01
[1] [3]
References [1] [1] [2] 4 L = 4π R2 σ T eff g = MG/R2 [1] [1] [3] [1]
Table 2. Log of the observations at Mt John Observatory, NZ, in Jan 2006. (1) and (2) Julian date (mean observation)
NASA
Kepler Mission
R C Smith 1983 L ∝ L!
!
M M!
"2.3
L ∝ L!
!
M M!
"4
Mass-Luminosity relation for B-type eclipsing binaries. Filled circles: primary components; open circles: secondary components.
Yakut et al. 2007
log
!
L L!
"
= 3.724 log
!
M M!
"
+ 0.162
Mass-Luminosity relation for 190 stars in 95 detached binary systems whose radii and masses are known to better than 3%
L ∝ M 3.5
Torres et al. 2010
15 September 2011
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