Diffuse Galactic gamma-rays: constraining cosmic-ray origin and propagation

Abstract

We have developed a model which aims to reproduce observational data of many kinds related to cosmic-ray (CR) origin and propagation: direct measurements of nuclei, antiprotons, electrons and positrons, gamma-rays, and synchrotron radiation. Our main results include evaluation of diffusion/convection and reacceleration models, estimates of the halo size, calculations of the interstellar positron and antiproton spectra, evaluation of alternative hypotheses of nucleon and electron interstellar spectra, and computation of the Galactic diffuse gamma-ray emission. Recently our CR propagation code has been generalized to include fragmentation networks of arbitrary complexity. The code can now provide an alternative to leaky-box calculations for full isotopic abundance calculations and has the advantage of including the spatial dimension which is essential for radioactive nuclei. Preliminary predictions for sub-Fe/Fe, 10Be/9Be and 26Al/27Al are presented in anticipation of new experimental isotopic data. We show that combining information from classical CR studies with gamma-ray and other data leads to tighter constraints on CR origin and propagation.

8 pages, 9 ps-figures. Talk given at the Int. Conf. on "Astrophysical Dynamics" (Evora, April 14-16, 1999). To appear in Astrophys. & Space Sci., D. Berry, D. Breitschwerdt, A. da Costa, J. Dyson (eds). More details can be found at http://www.gamma.mpe-garching.mpg.de/~aws/aws.html

References in corpus (1)

• Positrons from particle dark-matter annihilation in the Galactic halo: propagation Green's functions

Cited by in corpus (9)

• Secondary antiprotons and propagation of cosmic rays in the Galaxy and heliosphere
• High-Energy Gamma Rays from the Milky Way: Three-Dimensional Spatial Models for the Cosmic-Ray and Radiation Field Densities in the Interstellar Medium
• The Three-Dimensional Spatial Distribution of Interstellar Gas in the Milky Way: Implications for Cosmic Rays and High-Energy Gamma-Ray Emissions
• Spectrum and Morphology of the Two Brightest Milagro Sources in the Cygnus Region: MGRO J2019+37 and MGRO J2031+41
• Implications of current nuclear cross sections on secondary cosmic rays with the upcoming DRAGON2 code
• MGGPOD: a Monte Carlo Suite for Modeling Instrumental Line and Continuum Backgrounds in Gamma-Ray Astronomy
• Markov chain Monte Carlo analyses of the flux ratios of B, Be and Li with the DRAGON2 code
• FLUKA cross sections for cosmic-ray interactions with the DRAGON2 code
• Cross-Correlation of the Extragalactic Gamma-ray Background with Luminous Red Galaxies