Gamma-ray emission from classical novae

The main mechanisms through which classical novae can emit gamma-rays are reviewed. Gamma-ray emission has its origin on the disintegration of some short- and medium-lived radioactive nuclei, like 13N, 18F, 7Be and 22Na. As a result of the disintegration of these nuclei, the emission has two components: lines (511, 478 and 1275 keV) and continuum (between 20-30 keV and 511 keV). The detection of gamma-rays from novae would provide important diagnostics of the explosion mechanism and, specially, a direct insight of the nucleosynthesis processes: the 7Be and 22Na lines at 478 and 1275 keV directly reflect the amount of these nuclei in the ejecta, whereas the 511 keV line and the continuum reflect both the amount of 18F and 13N) and the dynamical properties of the expanding nova envelope. The unsuccessful, to date, attempts to detect gamma-rays from novae are also reviewed, together with the prospects for future detectability