Is High Primordial Deuterium Consistent With Galactic Evolution?

نویسندگان

  • Monica Tosi
  • Francesca Matteucci
  • Cristina Chiappini
چکیده

Galactic destruction of primordial deuterium is inevitably linked through star formation to the chemical evolution of the Galaxy. The relatively high present gas content and low metallicity suggest only modest D-destruction. In concert with deuterium abundances derived from solar system and/or interstellar observations this suggests a primordial deuterium abundance in possible conflict with data from some high-redshift, low-metallicity QSO absorbers. We have explored a variety of chemical evolution models including infall of processed material and early, supernovae-driven winds with the aim of identifying models with large D-destruction which are consistent with the observations of stellar-produced heavy elements. When such models are confronted with data we reconfirm that only modest destruction of deuterium (less than a factor of 3) is permitted. When combined with solar system and interstellar data these results favor the low deuterium abundances derived for the QSO absorbers observed by Tytler et al. (1996) and by Burles & Tytler (1996). Subject headings: Galaxy: evolution abundances

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تاریخ انتشار 1997