Particle Acceleration and Cosmic-Ray Origin in the Galaxy

TL;DR

This paper reviews recent gamma-ray observations of supernova remnants, providing evidence for electron and proton acceleration, and discusses their implications for understanding the origin of galactic cosmic rays.

Contribution

It presents new observational evidence from CANGAROO supporting supernova remnants as sources of galactic cosmic rays and details particle acceleration mechanisms.

Findings

Detection of TeV gamma-ray emissions from SNRs

Evidence of electron and proton acceleration in SNRs

Implications for cosmic-ray origin in the galaxy

Abstract

In 1990's Very High Energy Gamma-ray Astrophysics has dramatically advanced due to the Imaging Air \v{C}erenkov Telescopes(IACTs). After the first detection of TeV gamma-ray emission from the Crab nebula in 1989, several type of TeV gamma-ray sources, Active Galactic Nuclei(AGN), young pulsar, and SuperNova Remnant(SNR), have been detected. In those discoveries, recent detections of both synchrotron X-rays and TeV gamma-ray emissions from several SNRs are very significant. SNR has been widely believed to be an unique candidate of galactic cosmic-ray origin since the beginning of cosmic-ray physics, whereas little observational evidences have been reported so far. Those are expected to be a clue of not only the galactic cosmic-ray origin but also the understanding of the particle acceleration due to a diffusive shock. Here I present the recent results obtained by our group, CANGAROO, about the evidences of electron and proton acceleration in SNRs.