标题： 具有薄氢包层的DA白矮星的形成 显示英文标题

标题： The formation of DA white dwarfs with thin hydrogen envelopes

摘要： 我们研究了氦核DA型白矮星的形成和演化，它们的前身天体在离开AGB（渐近巨星分支）阶段后不久经历了一次晚期热脉冲（LTP）。为此，我们计算了一个初始质量为2.7倍太阳质量的恒星从零年龄主序阶段到白矮星阶段的完整演化过程。我们发现，在LTP后的演化过程中，大部分AGB残留物中的氢富材料被燃烧殆尽，因此，在进入白矮星冷却序列时，剩余的氢包层质量仅为10⁻⁶倍太阳质量，这一结果与某些ZZ Ceti型恒星的星震学推断一致。 显示英文摘要

摘要： We study the formation and evolution of DA white dwarfs, the progenitors of which have experienced a late thermal pulse (LTP) shortly after the departure from the thermally pulsing AGB. To this end, we compute the complete evolution of an initially 2.7 Mo star all the way from the zero-age main sequence to the white dwarf stage. We find that most of the original H-rich material of the post-AGB remnant is burnt during the post-LTP evolution, with the result that, at entering its white dwarf cooling track, the remaining H envelope becomes 10^-6 Mo in agreement with asteroseismological inferences for some ZZ Ceti stars.