Open AccessOn the photodissociation of H 2 by the first stars
Author(s) -
Glover S. C. O.,
Brand P. W. J. L.
Publication year - 2001
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2001.03993.x
Subject(s) - physics , photodissociation , stars , protogalaxy , astrophysics , star formation , universe , astronomy , photochemistry , lenticular galaxy , chemistry
The first star formation in the Universe is expected to take place within small protogalaxies, in which the gas is cooled by molecular hydrogen. However, if massive stars form within these protogalaxies, they may suppress further star formation by photodissociating the H 2 . We examine the importance of this effect by estimating the time‐scale on which significant H 2 is destroyed. We show that photodissociation is significant in the least massive protogalaxies, but becomes less so as the protogalactic mass increases. We also examine the effects of photodissociation on dense clumps of gas within the protogalaxy. We find that while collapse will be inhibited in low‐density clumps, denser ones may survive to form stars.