Open AccessHelium pre‐enrichment in the first stars
Author(s) -
Chuzhoy Leonid
Publication year - 2006
Publication title -
monthly notices of the royal astronomical society: letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.067
H-Index - 122
eISSN - 1745-3933
pISSN - 1745-3925
DOI - 10.1111/j.1745-3933.2006.00173.x
Subject(s) - globular cluster , physics , helium , stars , astrophysics , homogeneous , diffusion , horizontal branch , radiation pressure , astronomy , atomic physics , statistical physics , thermodynamics
We show that element diffusion can produce large fluctuations in the initial helium abundance of stars. Diffusion time‐scale, which in stellar cores is much larger than the Hubble time, can fall below 10 8 yr in the neutral gas clouds of stellar mass, dominated by collisionless dark matter or with dynamically important radiation or magnetic pressure. Helium diffusion may therefore explain the recent observations of globular clusters, which are inconsistent with initially homogeneous helium distribution.