A common solution of two cosmic puzzles

Shlomo Dado,Arnon Dar

doi:10.1088/1742-6596/718/6/062010

Abstract

We show that the properties of the background of astronomical neutrinos above 30 TeV, which was discovered with IceCube, are those expected from the all sky high-energy gamma-ray background radiation (GBR), which was measured below 2 TeV with Fermi-LAT, if both backgrounds were formed by the decay of mesons produced in hadronic collisions of the high energy cosmic rays (CRs) with diffuse matter in/near the CR sources.

Highlights

The high energy gamma ray background radiation (GBR) was first discovered 36 years ago with the SAS-2 satellite[1] and was later studied in detail with the Compton Gamma Ray Observatory[2] (CGRO) and more recently with the Fermi gamma ray satellite[3]
We show that the very high energy neutrino background radiation (NBR) discovered[1] with IceCube is that expected from the GBR observed with Fermi-large area telescope (LAT) at much lower energies[3], if both were produced by hadronic collisions of cosmic rays accelerated in relativistic jets with matter inside these jets, which are launched mostly in supernovae explosions of type Ic that produce the long duration gamma ray bursts[10,11] (GRBs), and by active galactic nuclei (AGN)
The highly relativistic jets launched in core collapse SN explosions of type Ic that produce long duration GRBs and by AGN accelerate through the Fermi mechanism[12] the swept in ionized matter in front of them[10,11] to cosmic ray energies with a power-law spectrum[12] dn/dE ∝ E−2. These cosmic rays escape the jets by diffusion in the turbulent magnetic fields inside the jets

Summary

A Common Solution of Two Cosmic Puzzles

The origin of the high energy gamma-ray background, which was measured with the large area telescope (LAT) aboard the Fermi satellite at energy below 820 GeV, and of the diffuse cosmic background of neutrinos, which was observed at much higher energies with the IceCube detector deep under the south pole ice, are among the current unsolved major cosmic puzzles. We show that their properties indicate a common origin: the decay of mesons produced in collisions of cosmic rays accelerated in relativistic jets with matter inside these jets. Their properties are those expected if the the highly relativistic jets are those emitted mainly in core collapse supernovae of type Ic, and by Active Galactic nuclei. PACS numbers: 98.70.Sa, 98.70.Vc, 98.70.Rz, 98.38.Mz arXiv:1411.2533v3 [astro-ph.HE] 20 May 2015

INTRODUCTION

HADRONIC PRODUCTION OF HIGH ENERGY GAMMA RAYS AND NEUTRINOS

ARE THE NBR AND GBR RELATED?

CONCLUSIONS

Photo mesons cannot produce the observed extragalactic γ-ray bacground

Upper bounds on the ENB