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OATS-DAUT SEMINAR
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Speaker: Francesca Primas (ESO, Garching b. Munchen)
Title: No dispersion and a plateau: what is going on with the easiest of the light elements ?
Date: Friday, June 4th, 2010
Time: 12:00
Venue: Villa Bazzoni
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Abstract:
Knowledge of lithium, beryllium, and boron abundances in stars of the
Galactic halo and disk plays a major role in our understanding of Big
Bang nucleosynthesis, cosmic-ray physics, and stellar interiors. Be9 and
B10 are expected to be "easy", since they are believed to originate entirely
from spallation reactions in the interstellar medium between alpha-particles
and protons and heavy nuclei like carbon, nitrogen, and oxygen.
However, they are both observationally challenging, with their main resonant
doublets falling respectively at 313 nm and at 250 nm. The advent of 8-10m
class telescopes equipped with highly sensitive (in the near-UV/blue) spectrographs
has opened up a new era of Be abundance studies. GHRS and then STIS on board
of HST have allowed detailed chemical studies below the atmospheric cut-off. Here,
I will review and discuss the most interesting results of recent observational campaigns
in terms of formation and evolution of these two light elements.
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contact: Paolo Molaro (OATS)