Pith. sign in

REVIEW 16 cited by

Evidence for strong extragalactic magnetic fields from Fermi observations of TeV blazars

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 1006.3504 v1 pith:2TA63Z5X submitted 2010-06-17 astro-ph.HE

Evidence for strong extragalactic magnetic fields from Fermi observations of TeV blazars

classification astro-ph.HE
keywords fieldsmagneticboundintergalacticgamma-raylambdalowermedium
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
0 comments
read the original abstract

Magnetic fields in galaxies are produced via the amplification of seed magnetic fields of unknown nature. The seed fields, which might exist in their initial form in the intergalactic medium, were never detected. We report a lower bound $B\ge 3\times 10^{-16}$~gauss on the strength of intergalactic magnetic fields, which stems from the nonobservation of GeV gamma-ray emission from electromagnetic cascade initiated by tera-electron volt gamma-ray in intergalactic medium. The bound improves as $\lambda_B^{-1/2}$ if magnetic field correlation length, $\lambda_B$, is much smaller than a megaparsec. This lower bound constrains models for the origin of cosmic magnetic fields.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 16 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Primordial Black Holes from Vector-Induced Curvature Perturbations Sourced by Primordial Magnetic Fields

    gr-qc 2026-06 unverdicted novelty 7.0

    Vector modes from primordial magnetic fields remain constant in a kination epoch and source second-order curvature perturbations scaling as P_R(k) ∝ k^{-5}, sufficient for PBH dark matter abundance in a Ratra-type mag...

  2. Energy spectrum of magnetic fields from electroweak symmetry breaking

    hep-ph 2026-04 unverdicted novelty 7.0

    An analytic energy spectrum for magnetic fields from electroweak symmetry breaking is obtained from random inhomogeneous Higgs configurations and validated with continuous-field simulations.

  3. Self-Consistent Parker Bound on Magnetic Monopoles

    hep-ph 2026-05 unverdicted novelty 6.0

    A self-consistent Parker bound on magnetic monopoles is derived using the galactic mean-field dynamo eigenmode and turbulent field seeding and acceleration, producing modified flux limits at low and intermediate masse...

  4. JWST Constraints on Primordial Magnetic Fields

    astro-ph.CO 2026-04 unverdicted novelty 6.0

    JWST UV luminosity function calibration of reionization history bounds primordial magnetic fields to √<B²> < 0.27 nG (n_B=-2) and < 0.18 nG (n_B=2) at 95% CL by ruling out double reionization at z≈24.

  5. Line-of-sight magnetic-field propagation effects on axion-like particle constraints from GRB 221009A

    hep-ph 2026-06 unverdicted novelty 5.0

    Intergalactic magnetic field strength, coherence scale, and stochastic properties significantly alter ALP exclusion contours from GRB 221009A, while host-galaxy and Milky Way fields cause only mild changes.

  6. Revisiting constraints on primordial vector modes and implications for sourced magnetic fields and observed $EB$ power spectrum

    astro-ph.CO 2026-05 unverdicted novelty 5.0

    Updated constraints on neutrino-sustained primordial vector modes imply magnetic fields too weak to seed observations and cannot reproduce the EB power spectrum while satisfying parity-even limits.

  7. Primordial Magnetogenesis and Gravitational Waves from ALP-assisted Phase Transition

    hep-ph 2026-04 unverdicted novelty 5.0

    ALP-assisted first-order phase transitions can explain observed intergalactic magnetic fields and produce detectable gravitational waves, linking cosmology with particle physics searches.

  8. Suppressed Magnetogenesis from Ultralight Dark Matter due to Finite Conductivity

    astro-ph.CO 2026-04 unverdicted novelty 5.0

    Finite conductivity of the plasma suppresses parametric resonance amplification of electromagnetic fields from ultralight pseudoscalar dark matter, making it impossible to generate magnetic fields of sufficient streng...

  9. Revisiting constraints on magnetogenesis from baryon asymmetry

    hep-ph 2025-09 unverdicted novelty 5.0

    Maximally helical primordial U(1)_Y magnetic fields can generate both intergalactic magnetic fields and baryon asymmetry; non-helical fields may work if Higgs dynamics compensate helicity loss to ≲10^{-9-10} precision...

  10. Primordial black holes and magnetic fields in conformal neutrino mass models

    hep-ph 2025-05 unverdicted novelty 5.0

    Conformal U(1)' seesaw models produce PBHs contributing to dark matter and helical magnetic fields at seesaw scales of 10^4-10^11 GeV, with observable GW, microlensing, and Hawking signals at LISA, Roman, and future g...

  11. An SKA-Low RM Grid for constraining the origin of cosmic magnetism

    astro-ph.CO 2026-06 unverdicted novelty 4.0

    Models predict SKA-Low will deliver an RM grid of over 50,000 sources in a 10,000 deg² survey at ~0.05 rad/m² precision, at least 10x denser than current m-λ grids.

  12. Gravitational Waves from Post-Inflationary Magnetism: Direct and Scalar-Induced Contributions

    astro-ph.CO 2026-05 unverdicted novelty 4.0

    In a post-inflationary magnetogenesis scenario with time-dependent gauge couplings, magnetic anisotropic stress dominates peak GW amplitude while scalar-induced terms matter on larger scales, both showing f^3 infrared...

  13. Primordial magnetic fields in the light of upcoming post-EoR Lyman-$\alpha$ and 21-cm observations

    astro-ph.CO 2026-04 unverdicted novelty 4.0

    Forecasts show DESI-like and SKA1-Mid observations could constrain primordial magnetic field amplitude and spectral index to roughly 10% precision via 21cm auto-spectrum and Lyα-21cm cross-spectrum.

  14. Study of Flat Spectrum Radio Quasars and BL Lacertae Objects as Sources of Diffusive Ultra High-Energy Cosmic Rays

    astro-ph.HE 2025-11 unverdicted novelty 4.0

    BL Lacs remain consistent with UHECR observations while FSRQs are disfavoured by anisotropy and source density mismatches after propagation modeling.

  15. On the contribution of galaxies to the magnetic field in cosmic voids

    astro-ph.CO 2025-10 unverdicted novelty 4.0

    Superposition of static galactic magnetic dipoles is screened by intergalactic plasma and cannot account for lower bounds on magnetic fields in cosmic voids from blazar gamma-ray data.

  16. High-Redshift Signatures from the Cosmic Dawn and the Epoch of Reionization

    astro-ph.CO 2026-06 unverdicted novelty 2.0

    A review chapter summarizing theoretical 21-cm signatures from Cosmic Dawn and Reionization and their detectability with SKA-Low.