A possible blazar spectral irregularity case caused by photon--axionlike-particle oscillations

Abstract

We report detection of a line-like feature in the $\gamma$-ray spectrum of the blazar B0516$-$621, for which the data obtained with the Large Area Telescope onboard {\it Fermi Gamma-Ray Space Telescope (Fermi)} are analyzed. The feature is at $\sim$7\,GeV and different analyses are conducted to check its real presence. We determine that it has a significance of 2.5--3.0$\sigma$, and cautiously note the presence of possible systematics in the data which could reduce the significance. This putative feature is too narrow to be explained with radiation processes generally considered for jet emission of blazars. Instead, it could be a signal due to the oscillations between photons and axion-like particles (ALPs) in the source's jet. We investigate this possibility by fitting the spectrum with the photon-ALP oscillation model, and find that the parameter space of ALP mass $m_a\le 10^{-8}$\,eV and the coupling constant (between photons and ALPs) $g_{a\gamma }$=1.16--1.48$\times 10^{-10}$\,GeV${}^{-1}$ can provide a fit to the line-like feature, while the magnetic field at the emission site of $\gamma$-rays is fixed at 0.7\,G. The ranges for $m_a$ and $g_{a\gamma }$ are in tension with those previously obtained from several experiments or methods, but on the other hand in line with some of the others. This spectral-feature case and its possible indication for ALP existence could be checked from similar studies of other blazar systems and also suggest a direction of effort for building future high-energy facilities that would have high sensitivities and spectral resolutions for searching for similar features.

arXiv comment13 pages, 8 figures, to appear in JCAP

References in corpus (28)

• Fermi Large Area Telescope Fourth Source Catalog
• Fermi Large Area Telescope Second Source Catalog
• The Spectral Energy Distribution of Fermi bright blazars
• The Low-Energy Frontier of Particle Physics
• New CAST Limit on the Axion-Photon Interaction
• Revisiting the SN1987A gamma-ray limit on ultralight axion-like particles
• The Fourth Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope
• Evidence for a new light spin-zero boson from cosmological gamma-ray propagation?
• Search for Spectral Irregularities due to Photon-Axionlike-Particle Oscillations With the Fermi Large Area Telescope
• Spectroscopy of Broad Line Blazars from 1LAC
• Detecting Axion-Like Particles With Gamma Ray Telescopes
• A New Bound on Axion-Like Particles
• Hardening of TeV gamma spectrum of AGNs in galaxy clusters by conversions of photons into axion-like particles
• On the jet properties of the gamma-ray loud active galactic nuclei
• Axion-Like Particles, Cosmic Magnetic Fields and Gamma-Ray Astrophysics
• Effects of Axion-Photon Mixing on Gamma-Ray Spectra from Magnetized Astrophysical Sources
• Axion-Like Particles and Recent Observations of the Cosmic Infrared Background Radiation
• On detecting oscillations of gamma rays into axion-like particles in turbulent and coherent magnetic fields
• The curvature of spectral energy distribution of blazars
• On the Relevance of Sharp Gamma-Ray Features for Indirect Dark Matter Searches
• Photons to axion-like particles conversion in Active Galactic Nuclei
• Analytical Solution of Magnetically Dominated Astrophysical Jets and Winds: Jet Launching, Acceleration, and Collimation
• Study of the variable broadband emission of Markarian 501 during the most extreme Swift X-ray activity
• Gamma-ray spectral modulations of Galactic pulsars caused by photon-ALPs mixing
• Searching for spectral oscillations due to photon-axionlike particle conversion using the Fermi-LAT observations of bright supernova remnants
• Relevance of jet magnetic field structure for blazar axionlike particle searches
• Determination of pseudo-Goldstone boson-photon coupling by the differential time delay of pulsar signals
• Hints of an axion-like particle mixing in the GeV gamma-ray blazar data?

Cited by in corpus (8)

• Searching for Axion-Like Particles with the Blazar Observations of MAGIC and Fermi-LAT
• On the origin and the detection of characteristic axion wiggles in photon spectra
• Photon-ALP oscillations inducing modifications to photon polarization
• Photon-ALP interaction as a measure of initial photon polarization
• Searching for Axion-Like Particles from Core-Collapse Supernovae with Fermi LAT's Low Energy Technique
• Axion-like Particle Effects on Photon Polarization in High-Energy Astrophysics
• X-ray polarimetric features of Gamma-ray Bursts across varied redshifts and hints for Axion-Like-Particles
• A GeV Gamma-Ray Spectral Excess in the Fermi Blazar 4FGL J0136.5+3906