The Isotopic Composition of Cosmic Ray

نویسندگان

  • R.
  • MEWALDT
  • R. E. VOGT
چکیده

We report new high resolution measurements of the elemental and isotopic composition of galactic cosmic ray B, C, N, and 0 nuclei with ~ 30 to ~ 130 MeV nucleon-•. These observations place limits on the isotopic composition of the cosmic ray source and restrict possible models of cosmic ray origin and propagation. In particular, we find that N is significantly depleted in the cosmic ray source with respect to the solar system and local interstellar medium, a result inconsistent with models in which a majority of cosmic rays are accelerated interstellar medium material. Subject headings: cosmic rays: abundancescosmic rays: general

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

Isotopic composition of cosmic-ray sources

We use the GALPROP code and the Advanced Composition Explorer (ACE) data to derive the cosmic ray (CR) isotopic composition at the sources. The composition is derived for two propagation models, diffusive reacceleration and plain diffusion. We show that the compositions derived assuming these two propagation models are different. We also compare the isotopic composition at the sources with the ...

متن کامل

The Isotopic Composition of the Anomalous Low-energy Cosmic Rays

We present new observations of the isotopic composition of low-energy He, C, N, 0, and Ne nuclei. The observations cover the energy interval from ,...., 5 to 30 MeV per nucleon, the energy range where the "anomalous cosmic ray" fluxes of He, N, 0, and Ne have been observed. We compare the isotopic composition of the anomalous cosmic rays with that of higher-energy galactic cosmic rays in an eff...

متن کامل

MAST: a mass spectrometer telescope for studies of the isotopic composition of solar, anomalous, and galactic cosmic ray nuclei

The Mass Spectrometer Telescope (MAST) on SAMPEX is designed to provide high resolution measurements of the isotopic composition of energetic nuclei from He to Ni (Z = 2 to 28) over the energy range from -10 to several hundred MeV/nuc. During large solar flares MAST will measure the isotopic abundances of solar energetic particles to determine directly the composition of the solar corona, while...

متن کامل

Cosmic-ray Sources and Source Composition

Present data on cosmic-ray elemental and isotopic relative abundances are shown to be unable to distinguish between various models of cosmic-ray sources and their composition. For example, the model of freshly nucleosynthesized material from supernova explosions as the cosmic-ray source is unable to account for some measured, key cosmic-ray elemental abundances. This and two other models are ev...

متن کامل

The P, S, Ar, and Ca isotopic composition of the galactic cosmic ray source

Galactic cosmic ray (GCR) measurements of the phosphorus, sulfur, argon, and calcium isotopes made by the Cosmic Ray Isotope Spectrometer (CRIS) aboard NASA’s Advanced Composition Explorer are reported over the energy range from ∼100 to ∼400 MeV/nucleon. The propagation of cosmic rays through the Galaxy and heliosphere is modeled to determine isotopic source abundance ratios P/S , S/S , Ar/Ar ,...

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 2009