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What is the problem with He-3We consider the galactic evolutionary history of He-3 in models which deplete deuterium by as much as a factor of 2 to approximately 15 from its primordial value to its present-day observed value in the interstellar medium (ISM). We show that when He-3 production in low-mass stars (1-3 solar mass) is included over the history of the galaxy, He-3 is greatly overproduced and exceeds the inferred solar values and the abundances determined in galactic H II regions. Furthermore, the ISM abundances show a disturbing dispersion which is difficult to understand from the point of view of standard chemical evolution models. In principle, resolution of the problem may lie in either (1) the calculated He-3 production in low-mass stars; (2) the observations of the He-3 abundance; or (3) an observational bias twoard regions of depleted He-3. Since He-3 observations in planetary nebula support the calculated He-3 production in low-mass stars, option (1) is unlikely. We will argue for option (3) since the He-3 interstellar observations are indeed made in regions dominated by massive stars in which He-3 is destroyed. In conclusion, we note that the problem with He-3 seems to be galactic and not cosmological.
Document ID
19950064061
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Olive, Keith A.
(University of Minnesota, Minneapolis, Minnesota United States)
Rood, Robert T.
(University of Virginia Virginia, United States)
Schramm, David N.
(University of Chicago, Chicago, Illinois United States)
Truran, James
(University of Chicago, Chicago, Illinois United States)
Vangioni-Flam, Elisabeth
(Institut d'Astrophysique de Paris Paris, France)
Date Acquired
August 17, 2013
Publication Date
May 10, 1995
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 444
Issue: 2
ISSN: 0004-637X
Subject Category
Astrophysics
Report/Patent Number
ISSN: 0004-637X
Accession Number
95A95660
Funding Number(s)
CONTRACT_GRANT: NSF AST-91-21169
CONTRACT_GRANT: DE-FG02-94ER-40823
CONTRACT_GRANT: NAGW-2381
Distribution Limits
Public
Copyright
Other

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