activity
19952000
collaborators

11 papers

astro-ph2000

LiBeB, O and Fe Evolution: Refractory Element and Cosmic Ray Transport Delays

R. Ramaty, B. Kozlovsky, R. E. Lingenfelter

Employing a Monte-Carlo based evolutionary code, we show that the delay of Fe deposition relative to O, due to the incorporation of supernova ejecta refractories in high velocity g…

astro-ph2000

LiBeB Evolution: Three Models

R. Ramaty, R. E. Lingenfelter, B. Kozlovsky

We consider the three principal LiBeB evolutionary models, CRI in which the cosmic-ray source at all epochs of Galactic evolution is the average ISM, CRI+LECR in which metal enrich…

astro-ph1999

Nonthermal X-Rays from the Galactic Ridge: a Tracer of Low Energy Cosmic Rays ?

V. Tatischeff, R. Ramaty, A. Valinia

A distinct low energy cosmic-ray component has been proposed to explain the essentially constant Be/Fe ratio at low metallicities. Atomic collisions of such low energy ions produce…

astro-ph1999

Spallogenic Light Elements and Cosmic-Ray Origin

R. Ramaty, R. E. Lingenfelter

Using a Monte Carlo code which incorporates the delayed mixing into the ISM of supernovae nucleosynthetic yields and ejecta kinetic energies (including events with very large energ…

astro-ph1998

Solar Flares: Gamma Rays

Reuven Ramaty, Natalie Mandzhavidze

We briefly review the theory of gamma ray production in solar flares and present the highlights of the observations and their implications. Specifically: (i) the gamma ray data sho…

astro-ph1998

Early Galactic Li, Be and B: Implications on Cosmic Ray Origin

Reuven Ramaty, Richard Lingenfelter

Be abundances of old, low metallicity halo stars have major implications on cosmic-ray origin, requiring acceleration out of fresh supernova ejecta. The observed, essentially const…