摘要
High resolution (R^40,000) and high signal-to-noise ratio (】150) spectra of two solar twins, HD146233 and HD195034, are obtained with the Coude Echelle Spectrograph at the 2.16 m telescope of the National Astronomical Observatories of Chinese Academy of Sciences (Xinglong, China). Based on the detailed spectrum match, comparisons of chemical composition and chromospheric activity, HD146233 and HD195034 are confirmed that they are similar to the Sun except for lithium abundance, which is higher than the solar value. Moreover, among nine solar twin candidates (including HD146233 and HD195034) found in the previous works, we have picked out six good solar twin candidates based on newly-derived homogenous parameters, and collected their colors in the Johnson/Cousins, Tycho, 2MASS and Strmgren system from the literature. The average color are (B-V)⊙=0.644 mag, (V-Ic)⊙=0.707 mag, (BT-VT)⊙=0.725 mag, (J-H)⊙=0.288 mag, (H-K)⊙=0.066 mag, (v-y)⊙=1.028 mag, (v-b)⊙=0.619 mag, (u-v)⊙=0.954 mag and (b-y)⊙=0.409 mag, which represent the solar colors with higher precision than previous works.
High resolution (R^40,000) and high signal-to-noise ratio (>150) spectra of two solar twins, HD146233 and HD195034, are obtained with the Coude Echelle Spectrograph at the 2.16 m telescope of the National Astronomical Observatories of Chinese Academy of Sciences (Xinglong, China). Based on the detailed spectrum match, comparisons of chemical composition and chromospheric activity, HD146233 and HD195034 are confirmed that they are similar to the Sun except for lithium abundance, which is higher than the solar value. Moreover, among nine solar twin candidates (including HD146233 and HD195034) found in the previous works, we have picked out six good solar twin candidates based on newly-derived homogenous parameters, and collected their colors in the Johnson/Cousins, Tycho, 2MASS and Strmgren system from the literature. The average color are (B-V)⊙=0.644 mag, (V-Ic)⊙=0.707 mag, (BT-VT)⊙=0.725 mag, (J-H)⊙=0.288 mag, (H-K)⊙=0.066 mag, (v-y)⊙=1.028 mag, (v-b)⊙=0.619 mag, (u-v)⊙=0.954 mag and (b-y)⊙=0.409 mag, which represent the solar colors with higher precision than previous works.
基金
supported by the National Natural Science Foundation of China (Grant Nos. 10821061 and 10673015)
the National Basic Research Program of China (Grant No. 2007CB815103/815403)
the National High Technology Research and Development Program of China (Grant No. 2006AA01A120)
