The solar disk at high energies

Abstract

High energy cosmic rays "illuminate" the Sun and produce an image that could be observed in up to five different channels: a cosmic ray shadow (whose energy dependence has been studied by HAWC); a gamma ray flux (observed at $E\le 200$ GeV by Fermi-LAT); a muon shadow (detected by ANTARES and IceCube); a neutron flux (undetected, as there are no hadronic calorimeters in space); and a flux of high energy neutrinos. Since these signals are correlated, the ones already observed can be used to reduce the uncertainty in the still undetected ones. Here we define a simple set up that uses the Fermi-LAT and HAWC observations to imply very definite fluxes of neutrons and neutrinos from the solar disk. In particular, we provide a fit of the neutrino flux at 10 GeV-10 TeV that includes its dependence on the zenith angle and on the period of the solar cycle. This flux represents a neutrino floor in indirect dark matter searches. We show that in some benchmark models the current bounds on the dark matter-nucleon cross section push the solar signal below this neutrino floor.

14 pages, fits and Fig. 8 corrected, results unchanged

References in corpus (5)

• Dark Matter Search Results from the Complete Exposure of the PICO-60 C${}_3$F${}_8$ Bubble Chamber
• Fermi-LAT Observations of Two Gamma-Ray Emission Components from the Quiescent Sun
• Gamma-ray emission from the solar halo and disk: a study with EGRET data
• High energy neutrinos from the Sun
• Neutrino events within muon bundles at neutrino telescopes

Cited by in corpus (5)

• The TeV Sun Rises: Discovery of Gamma rays from the Quiescent Sun with HAWC
• Small-Scale Magnetic Fields are Critical to Shaping Solar Gamma-Ray Emission
• Role of magnetic arcades in explaining the puzzle of the gamma-ray emission from the solar disk
• First Observations of Solar Halo Gamma Rays Over a Full Solar Cycle
• Angular Distribution of Gamma Rays Produced in Proton-Proton Collisions