Physical origin of very-high-energy gamma rays from the low-luminosity active galactic nucleus NGC 4278 and implications for neutrino observations

Abstract

Relativistic jets in active galactic nuclei (AGNs) are known to accelerate particles to extreme energies, yet the physical origin of very-high-energy (VHE) emission from low-luminosity (LL) AGNs remains unclear. NGC 4278, a nearby LL AGN, has recently been identified as a VHE source following detections by LHAASO. In this work, we present a multiwavelength and multimessenger analysis to investigate the origin of this emission. Swift X-Ray Telescope monitoring reveals a quasi-quiescent state characterized by the low X-ray flux. Modeling the broadband spectral energy distribution with the leptohadronic code AMES, we find that a standard one-zone synchrotron self-Compton model underpredicts the VHE flux, unless a relatively high Doppler factor ($\delta \gtrsim 6$) is invoked. Alternatively, an external inverse-Compton (EIC) scenario-scattering seed photons from a radiatively inefficient accretion flow-provides a good description of the broadband emission with modest jet power and Doppler factor. We further explore neutrino production within a leptohadronic framework. The EIC model in the quasi-quiescent state yields the largest predicted number of muon neutrinos, reaching $N_{{\nu }_{\mu }}\sim 0.001$ over 15 yr of IceCube observations (assuming that 0.1\% of the Eddington luminosity is converted into high-energy protons). Future multimessenger observations are essential to unveil the details of the high-energy processes of NGC 4278.

arXiv comment10 pages, 8 figures, 5 tables, Published in The Astrophysical Journal

References in corpus (55)

• emcee: The MCMC Hammer
• The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
• Nuclear Activity in Nearby Galaxies
• Neutrino emission from the direction of the blazar TXS 0506+056 prior to the IceCube-170922A alert
• Calibration of X-ray absorption in our Galaxy
• Leptonic and Hadronic Modeling of Fermi-Detected Blazars
• Nonthermal Electrons in Radiatively Inefficient Accretion Flow Models of Sagittarius A*
• Incremental Fermi Large Area Telescope Fourth Source Catalog
• Evidence for neutrino emission from the nearby active galaxy NGC 1068
• A relationship between AGN jet power and radio power
• CRATES: An All-Sky Survey of Flat-Spectrum Radio Sources
• Time-integrated Neutrino Source Searches with 10 years of IceCube Data
• The Spectral Energy Distributions of Low-Luminosity Active Galactic Nuclei
• The Cosmic Lens All-Sky Survey: I. Source selection and observations
• An Accurate Flux Density Scale from 1 to 50 GHz
• Sub-milliarcsecond Imaging of Quasars and Active Galactic Nuclei. IV. Fine Scale Structure
• Magnetic acceleration of relativistic AGN jets
• Hidden Cosmic-Ray Accelerators as an Origin of TeV-PeV Cosmic Neutrinos
• Diffuse Neutrino Intensity from the Inner Jets of Active Galactic Nuclei: Impacts of External Photon Fields and the Blazar Sequence
• A Multimessenger Picture of the Flaring Blazar TXS 0506+056: implications for High-Energy Neutrino Emission and Cosmic Ray Acceleration
• Radio Sources in Low-Luminosity Active Galactic Nuclei.IV. Radio Luminosity Function, Importance of Jet Power, and Radio Properties of the Complete Palomar Sample
• Spectral Models of Advection-Dominated Accretion Flows with Winds
• The First LHAASO Catalog of Gamma-Ray Sources
• Blazars as Ultra-High-Energy Cosmic-Ray Sources: Implications for TeV Gamma-Ray Observations
• TeV BL Lac objects at the dawn of the Fermi era
• Relativistic Shocks: Particle Acceleration and Magnetization
• Methods for point source analysis in high energy neutrino telescopes
• Techniques and Review of Absolute Flux Calibration from the Ultraviolet to the Mid-Infrared
• MOJAVE - XIV. Shapes and opening angles of AGN jets
• An X-ray view of 82 LINERs with Chandra and XMM-Newton data
• Photohadronic origin of $\gamma$-ray BL Lac emission: implications for IceCube neutrinos
• Spectral Models for Low-luminosity Active Galactic Nuclei in LINERs: The Role of Advection-dominated Accretion and Jets
• Radiation Mechanisms and Physical Properties of GeV-TeV BL Lac Objects
• Innermost collimation structure of the M87 jet down to ~ten Schwarzschild radii
• Variable Gamma-ray Emission Induced by Ultra-High Energy Neutral Beams: Application to 4C +21.35
• The time-dependent one-zone hadronic model - First principles
• Hidden Hearts of Neutrino Active Galaxies
• On the direct correlation between gamma-rays and PeV neutrinos from blazars
• The HST view of LINERs nuclei: evidence for a dual population?
• Hot self-similar relativistic MHD flows
• Causal connection in parsec-scale relativistic jets: results from the MOJAVE VLBI survey
• A survey of polarization in the JVAS/CLASS flat-spectrum radio source surveys: I. The data and catalogue production
• The two sided parsec scale structure of the Low Luminosity Active Galactic Nucleus in NGC 4278
• A Neutral Beam Model for High-Energy Neutrino Emission from the Blazar TXS 0506+056
• Multi-messenger tests of cosmic-ray acceleration in radiatively inefficient accretion flows
• Soft gamma rays from low accreting supermassive black holes and connection to energetic neutrinos
• Hadronic High-energy Emission from Magnetically Arrested Disks in Radio Galaxies
• X-ray and multiwavelength view of NGC 4278. A LINER-Seyfert connection?
• Revealing the Production Mechanism of High-Energy Neutrinos from NGC 1068
• AGN activity and the misaligned hot ISM in the compact radio elliptical NGC4278
• Discovery of Very-high-energy Gamma-ray Emissions from the Low Luminosity AGN NGC 4278 by LHAASO
• Nuclear and electromagnetic cascades induced by ultrahigh-energy cosmic rays in radio galaxies: implications for Centaurus A
• The ultraviolet flare at the center of the elliptical galaxy NGC 4278
• Multiple Emission Regions in Jets of Low Luminosity Active Galactic Nucleus in NGC 4278
• Insights from leptohadronic modelling of the brightest blazar flare