Supernova connection of unidentified ultra high energy gamma-ray source LHAASO J2108+5157

Abstract

We present a simple phenomenological model of hadronic interaction between protons accelerated in an old supernova remnant (SNR) and cold protons situated within the associated molecular clouds (MCs). The accelerated protons from the old SNR escaped the SNR shock front, and got injected into the MCs at an earlier time, producing ultra high energy gamma-rays and neutrinos through inelastic proton-proton interaction. We also take into account the acceleration and subsequent escape of electrons from the SNR shock front. The escaped electrons produce gamma-rays through various radiative cooling mechanisms, after getting injected into the MCs. We use the model discussed in this letter to explain the multiwavelength (MWL) spectral energy distribution (SED) of unidentified Galactic ultra high energy gamma-ray source LHAASO J2108+5157. We also discuss the feasibility of applying this model in other cases as well. Future observations can test the viability of the model discussed in this letter, which will in turn confirm that the SNRs can, in fact, accelerate particles up to PeV energies.

6 pages, 2 figures, 1 table; accepted for publication in Monthly Notices of the Royal Astronomical Society Letters (MNRASL)

References in corpus (12)

• IceCube-Gen2: The Window to the Extreme Universe
• Physical properties of molecular clouds for the entire Milky Way disk
• Parametrization of gamma-ray production cross-sections for pp interactions in a broad proton energy range from the kinematic threshold to PeV energies
• A radiation transfer model for the Milky-Way: I. Radiation fields and application to High Energy Astrophysics
• Gamma rays from molecular clouds
• Unified model for the gamma-ray emission of supernova remnants
• Discovery of the Ultra-high energy gamma-ray source LHAASO J2108+5157
• Evidence that Ultra-High-Energy Gamma Rays are a Universal Feature Near Powerful Pulsars
• Discovery of a new $\gamma$-ray source LHAASO J0341+5258 with emission up to 200TeV
• Revealing a peculiar supernova remnant G106.3+2.7 as a petaelectronvolt proton accelerator with X-ray observations
• Ultra-high Energy Gamma-rays from Past Explosions in our Galaxy
• LHAASO J2226+6057 as a pulsar wind nebula

Cited by in corpus (5)

• Evidence for a gamma-ray molecular target in the enigmatic PeVatron candidate LHAASO J2108+5157
• Dissecting the emission from LHAASO J0341+5258: implications for future multi-wavelength observations
• VERITAS and HAWC observations of unidentified source LHAASO J2108+5157
• Are Kronberger 80 and/or Kronberger 82 regions PeVatron candidates for LHAASO J2108+5157?
• Investigating the emission signatures of pulsar halo candidate HESS J1813-126