Strong gravitational lensing of blazar gamma-radiation and intergalactic magnetic fields
arXiv:2311.01207 · doi:10.1088/1674-1137/ad0b6a
Abstract
The influence of intergalactic magnetic fields on the strong gravitational lensing of blazar secondary gamma radiation is discussed. Currently, two cases of strong gravitational lensing of blazar gamma-radiation are known, where radiation is deflected by galaxies on the line of sight between the blazars and the Earth. The magnetic field can affect the movements of electron-positron pairs generated by primary radiation, and thereby change the directions of secondary gamma radiation. It modifies the equation of the gravitational lens and leads to the dependence of the observed signal in the secondary gamma radiation on the energy of photons and on the magnetic field. Accordingly, it is possible in principle to estimate the intergalactic magnetic fields from the time delay of signals, from the angular position of images (for future high-resolution gamma-ray telescopes) or from the shape of the observed energy spectrum. This method is demonstrated by the example of the blazar B0218+357. In this case however it is not possible to obtain useful constraints due to the large distances to the blazar and the lens galaxy. The result is only a lower limit on the magnetic field G, which is weaker than other existing constraints. But the future discoveries of lensed blazars may provide more favourable opportunities for measuring the magnetic fields, especially with the help of new generation of gamma-ray telescopes such as e-ASTROGAM, GECAM, and SVOM as well as future gamma-ray telescopes with high angular resolution, ~0.1''.
arXiv comment8 pages, 2 figures, to be published in Chinese Physics C
References in corpus (28)
- Cosmological Magnetic Fields: Their Generation, Evolution and Observation
- Lower limit on the strength and filling factor of extragalactic magnetic fields
- Evidence for Gamma-Ray Halos Around Active Galactic Nuclei and the First Measurement of Intergalactic Magnetic Fields
- Constraints on the Intergalactic Magnetic Field with Gamma-Ray Observations of Blazars
- The toes of the ultra high energy cosmic ray spectrum
- Evidence for GeV Pair Halos around Low Redshift Blazars
- Gamma-ray induced cascades and magnetic fields in intergalactic medium
- Lensing of ultra-high energy cosmic rays in turbulent magnetic fields
- The Hubble constant from gravitational lens CLASS B0218+357 using the Advanced Camera for Surveys
- Determination of the Point-Spread Function for the Fermi Large Area Telescope from On-orbit Data and Limits on Pair Halos of Active Galactic Nuclei
- Models for the lens and source of B0218+357 - A LensClean approach to determine H0
- The Galactic magnetic field as spectrograph for ultra-high energy cosmic rays
- On detecting oscillations of gamma rays into axion-like particles in turbulent and coherent magnetic fields
- Gamma-ray flaring activity from the gravitationally lensed blazar PKS 1830-211 observed by Fermi LAT
- A method of measurement of extragalactic magnetic fields by TeV gamma ray telescopes
- Fermi-LAT Detection of Gravitational Lens Delayed Gamma-ray Flares from Blazar B0218+357
- No evidence for gamma-ray halos around active galactic nuclei resulting from intergalactic magnetic fields
- First evidence for a gravitational lensing-induced echo in gamma rays with Fermi LAT
- Blazar halos as probe for extragalactic magnetic fields and maximal acceleration energy
- The Structure of the Strongly Lensed Gamma-ray Source B2 0218+35
- UHECR observations and lensing in the magnetic field of the Virgo cluster
- Resolving the High Energy Universe with Strong Gravitational Lensing: The Case of PKS 1830-211
- A revised lens time delay for JVAS B0218+357 from a reanalysis of VLA monitoring data
- Strong gravitational lensing as a tool to investigate the structure of jets at high energies
- Towards discrimination between galactic and intergalactic axion-photon mixing
- Prospects for future very high-energy gamma-ray sky survey: impact of secondary gamma rays
- How gravitational lensing helps gamma-ray photons avoid absorption
- Cosmic Magnetic Lenses