太阳大气锂丰度的衰减

太阳大气锂的丰度７Ｌｉ／Ｈ＝１０－１１（按原子数计）。或［７Ｌｉ］＝ｌｏｇ（７Ｌｉ／Ｈ）＋１２＝１０．它比太阳系原始星云和银河系星际介质钾的丰度要低约两个数量级．因此太阳在它形成之后，其大气锂必定经受了严重衰减．然而年轻的银河疏散星团（如昂星团和英仙ａ星团）中有效温度高于５５００ Ｋ的主序星，其锂丰度都基本是正常的，井末呈现明显的衰减．这充分说明，太阳型恒星锂的衰减主要发生在主序阶段，而非在主序前的演化阶段． 在恒星中，７Ｌｉ是通过核反应７Ｌｉ（ｐ，ａ）４Ｈｅ，而毁坏．上述反应在Ｔ≥ ２．５×１０…

Lithium Depletion in the Solar Atmospere

Using a complete non-local convection theory, we carried out the theoretical calculations of 7Li depletion of the solar convective envelope models with different convective parameters c1 and C2, and got a model of the solar convection zone consistent with the observed 7Li abundance and the depth of the solar convection zone determined by helioseismic techniques. The overshooting distance of effective non-local convective mixing of 7Li is very extensive, which is about 1.07 Hp or 0.09 R. However, the super-radiation temperature zone is much narrower, and it is only 0.20 Hp or 0.01GR.