ELFT HÍRADÓ

[Zoltan Mate <mate AT atomki.mta.hu>]

Az MTA Atommagkutató Intézetének előadótermében
(Debrecen, Bem tér 18/c. 12. ép. III. em.)
2013. január 10-én, csütörtökön 11:00-kor


                     Thomas Rauscher
                  (University of Basel)

                  The p-Nucleus Puzzle

címmel előadást tart.

Az előadás előtt 10:30-tól tea, vendégeket szívesen látunk.


                                           Máté Zoltán


KIvonat:

The origin of the intermediate and heavy elements beyond Fe has been a
long-standing, important question in astronomy and astrophysics. The
neutron capture s- and r-processes synthesize the bulk of those nuclei.
While AGB and massive stars were found to contribute to the s-process,
the site of the r-process still remains unknown. Moreover, a number of
naturally occurring, proton-rich isotopes (the p-nuclei) cannot be made
in the s- and r-processes. Although their natural abundances are tiny
compared to isotopes produced in neutron-capture nucleosynthesis, their
production is even more problematic. The long-time favored process,
photodisintegration of material in the O/Ne-shell of a massive star
during its final core-collapse supernova explosion, fails to produce the
required amounts of p-nuclei in several mass ranges. Several alternative
sites have been proposed but so far no conclusive evidence has been
found to favor one or the other. Further important uncertainties stem
from the reaction rates used in the modeling of the thermonuclear
burning. This raises the interesting question whether improved nuclear
physics may (fully or partially) cure the current model deficiences.
Investigations in astrophysical and nuclear models, together with
various "observational" information (obtained from stellar spectra,
meteoritic inclusions, and nuclear experiments) comprise the pieces
which have to be put together to solve the puzzle of the origin of the
p-nuclei. It is an excellent example for the multifaceted,
interdisciplinary approaches required to understand nucleosynthesis.