The $\gamma$-ray Emission of Star-Forming Galaxies

Understand

A majority of the $\gamma$-ray emission from star-forming galaxies is generated by the interaction of high-energy cosmic rays with the interstellar gas and radiation fields.

• Star-forming galaxies are expected to contribute to both the extragalactic $\gamma$-ray background and the IceCube astrophysical neutrino flux.
• Using roughly 10\,years of $\gamma$-ray data taken by the {\it Fermi} Large Area Telescope, in this study we constrain the $\gamma$-ray properties of star-forming galaxies.
• We report the detection of 11 bona-fide $\gamma$-ray emitting galaxies and 2 candidates.