On Solar System and Cosmic Rays Nucleosynthesis and Spallation Processes

نویسنده

  • Stepan G. Mashnik
چکیده

A brief survey of nuclide abundances in the solar-system and in cosmic rays and of the believed mechanisms of their synthesis is given. The role of spallation processes in nucleosynthesis is discussed. A short review of recent measurements, compilations, calculations, and evaluations of spallation cross sections relevant to nuclear astrophysics is given as well. It is shown that in some past astrophysical simulations, old experimental nuclear data and theoretical cross sections that are in poor agreement with recent measurements and calculations were used. New astrophysical simulations using recently measured and reliably calculated nuclear cross sections, further researches in obtaining better cross sections, and production of evaluated spallation cross sections libraries for astrophysics are suggested. Subject headings: Nucleosynthesis, abundances — nuclear reactions, spallation cross sections, data libraries

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Applications of Abundance Data and Requirements for Cosmochemical Modeling

Understanding the evolution of the universe from Big Bang to its present state requires an understanding of the evolution of the abundances of the elements and isotopes in galaxies, stars, the interstellar medium, the Sun and the heliosphere, planets and meteorites. Processes that change the state of the universe include Big Bang nucleosynthesis, star formation and stellar nucleosynthesis, gala...

متن کامل

Testing Spallation Processes with Beryllium and Boron

The nucleosynthesis of Be and B by spallation processes provides unique insight into the origin of cosmic rays. Namely, different spallation schemes predict sharply different trends for the growth of LiBeB abundances with respect to oxygen. “Primary” mechanisms predict BeB ∝ O, and are well motivated by the data if O/Fe is constant at low metallicity. In contrast, “secondary” mechanisms predict...

متن کامل

Implications of a new temperature scale for halo dwarfs on LiBeB and chemical evolution

Big bang nucleosynthesis (BBN) and the cosmic baryon density from cosmic microwave background anisotropies together predict a primordial Li abundance a factor of 2–3 higher than that observed in galactic halo dwarf stars. A recent analysis of Li observations in halo stars, using significantly higher surface temperature for these stars, found a higher Li plateau abundance. These results go a lon...

متن کامل

Spatial Origin of Galactic Cosmic Rays in Diffusion Models : I - Standard sources in the Galactic disk

The propagation of Galactic Cosmic Ray nuclei having energies between 100 MeV/nuc and several PeV/nuc is strongly believed to be of diffusive nature. The particles emitted by a source located at a given position in the disk do not pervade the whole Galaxy, but are rather confined to a smaller region whose spatial extension is related to the height of the diffusive halo, the Galactic wind and th...

متن کامل

The Revival of Galactic Cosmic Ray Nucleosynthesis?

Because of the roughly linear correlation between Be/H and Fe/H in low metallicity halo stars, it has been argued that a “primary” component in the nucleosynthesis of Be must be present in addition to the “secondary” component from standard Galactic cosmic ray nucleosynthesis. In this paper we critically re-evaluate the evidence for the primary versus secondary character of Li, Be, and B evolut...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2000