关于氘的原初丰度

A Study on the Primordial Abundance of Deuterium

本文用均匀的化学演化模型讨论了银河系中氘和氦３的丰度演化．发现当采用大质量恒星占比例较低的初始质量函数，并考虑到气体内落的影响，原初氘丰度ｙ２ｐ～（２－３）×１０－５，将能与太阳系附近的实测相洽．这结果大体与类星体吸收云中氘丰度实测的低值相一致，而吸收云中测得的氘丰度的高值却与星系化学演化模型不一致．此外讨论了这结果可能给大爆炸核合成理论的检验带来的问题．

The chemical evolution of D and He3 in the Galaxy is considered by using homogeneously evolving models. It is shown that only if Scalo's initial mass function is adopted and the gas infall is taken into consideration, the models with y 2p < (2-3)×10 -5 as initial condition can evolve to reproduce the observed abundance of D and He3 in the solar neighborhood. Our result accords with the low values of D abundance recently observed in QSO absorption spectrum but not with the high values. Possible problems with the Big Bang nucleosynthesis implied by this result are discussed.