Abstract
The detection of high-energy astrophysical neutrinos and ultra-high-energy cosmic rays (UHECRs) provides a new way to explore sources of cosmic rays. One of the highest energy neutrino events detected by IceCube, tagged as IC35, is close to the UHECR anisotropy region detected by Pierre Auger Observatory. The nearby starburst (SB) galaxy, NGC 4945, is close to this anisotropic region and inside the mean angular error of the IC35 event. Considering the hypernovae contribution located in the SB region of NGC 4945, which can accelerate protons up to $\ensuremath{\sim}{10}^{17}\text{ }\text{ }\mathrm{eV}$ and inject them into the interstellar medium, we investigate the origin of this event around this starburst galaxy. We show that the interaction of these protons with the SB region's gas density could explain Fermi-LAT gamma-ray and radio observations if the magnetic field's strength in the SB region is the order of $\ensuremath{\sim}\mathrm{mG}$. Our estimated PeV neutrino events, in ten years, for this source is approximately 0.01 ($4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$) if a proton spectral index of 2.4 (2.7) is considered, which would demonstrate that IC35 is not produced in the central region of this SB galaxy. Additionally, we consider the superwind region of NGC 4945 and show that protons can hardly be accelerated in it up to UHECRs.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.