Cosmic rays, γ-rays, and neutrinos in the starburst nuclei of Arp 220

@article{YoastHull2015CosmicR,
  title={Cosmic rays, $\gamma$-rays, and neutrinos in the starburst nuclei of Arp 220},
  author={Tova M. Yoast-Hull and John S. Gallagher and Ellen G. Zweibel},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2015},
  volume={453},
  pages={222-228}
}
The cores of Arp 220, the closest ultra-luminous infrared starburst galaxy, provide an opportunity to study interactions of cosmic rays under extreme conditions. In this paper, we model the populations of cosmic rays produced by supernovae in the central molecular zones of both starburst nuclei. We find that ~65 - 100% of cosmic rays are absorbed in these regions due to their huge molecular gas contents, and thus, the nuclei of Arp 220 nearly complete proton calorimeters. As the cosmic ray… 

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