Related Experiment Video
Updated: Jun 10, 2026

Visualization of Low-Level Gamma Radiation Sources Using a Low-Cost, High-Sensitivity, Omnidirectional Compton Camera
Published on: January 30, 2020
Gamma-ray emission concurrent with the nova in the symbiotic binary V407 Cygni
1, A A Abdo, M Ackermann
1Space Science Division, Naval Research Laboratory, Washington, DC 20375, USA.
Abstract:
Novae are thermonuclear explosions on a white dwarf surface fueled by mass accreted from a companion star. Current physical models posit that shocked expanding gas from the nova shell can produce x-ray emission, but emission at higher energies has not been widely expected. Here, we report the Fermi Large Area Telescope detection of variable gamma-ray emission (0.1 to 10 billion electron volts) from the recently detected optical nova of the symbiotic star V407 Cygni. We propose that the material of the nova shell interacts with the dense ambient medium of the red giant primary and that particles can be accelerated effectively to produce pi(0) decay gamma-rays from proton-proton interactions. Emission involving inverse Compton scattering of the red giant radiation is also considered and is not ruled out.
Related Concept Videos
Emission Spectra
X-ray Imaging
Atomic Emission Spectroscopy: Interference
Atomic Emission Spectroscopy: Overview
Types of Radioactivity
Alpha (α) decay is the emission of an α particle from the nucleus. For example, polonium-210 undergoes α decay:
Atomic Emission Spectroscopy: Instrumentation

