Axions produced in supernovae generate a diffuse gamma-ray signal through conversion in magnetic fields, yielding competitive constraints on the axion-photon coupling from COMPTEL, EGRET, and Fermi-LAT data plus forecasts for future MeV telescopes.
hub Mixed citations
The spectrum of isotropic diffuse gamma-ray emission between 100 MeV and 820 GeV
Mixed citation behavior. Most common role is background (67%).
abstract
The {\gamma}-ray sky can be decomposed into individually detected sources, diffuse emission attributed to the interactions of Galactic cosmic rays with gas and radiation fields, and a residual all-sky emission component commonly called the isotropic diffuse {\gamma}-ray background (IGRB). The IGRB comprises all extragalactic emissions too faint or too diffuse to be resolved in a given survey, as well as any residual Galactic foregrounds that are approximately isotropic. The first IGRB measurement with the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi) used 10 months of sky-survey data and considered an energy range between 200 MeV and 100 GeV. Improvements in event selection and characterization of cosmic-ray backgrounds, better understanding of the diffuse Galactic emission, and a longer data accumulation of 50 months, allow for a refinement and extension of the IGRB measurement with the LAT, now covering the energy range from 100 MeV to 820 GeV. The IGRB spectrum shows a significant high-energy cutoff feature, and can be well described over nearly four decades in energy by a power law with exponential cutoff having a spectral index of $2.32\pm0.02$ and a break energy of $(279\pm52)$ GeV using our baseline diffuse Galactic emission model. The total intensity attributed to the IGRB is $(7.2\pm0.6) \times 10^{-6}$ cm$^{-2}$ s$^{-1}$ sr$^{-1}$ above 100 MeV, with an additional $+15$%/$-30$% systematic uncertainty due to the Galactic diffuse foregrounds.
hub tools
citation-role summary
citation-polarity summary
representative citing papers
The cosmologically integrated neutrino emission from supermassive black hole coronae in Seyfert galaxies can account for the sub-PeV diffuse extragalactic neutrino flux observed by IceCube.
Non-thermal production via late-decaying reheatons can achieve the observed dark matter density for sexaquarks by controlling branching fractions and coalescence probabilities, unlike thermal freeze-out which underproduces them by many orders of magnitude.
Supernova models yield coupling limits g_a ≲ 0.9×10^{-10} and g_φ ≲ 0.4×10^{-10} for masses above 100 keV from gamma-ray observations, plus stronger trapping-regime limits from explosion energy, that are difficult to reconcile with a muon g-2 explanation.
A proton spectrum with index -3.1 interacting with 0.3 keV X-rays via the Delta resonance reproduces the observed 30 TeV neutrino break and limits the accompanying gamma-ray cascade contribution to ~10% of the isotropic background at 3 GeV.
Calculations indicate AMEGO-X could detect PBH transits within 0.1 AU while HAWC and LHAASO could observe explosions out to 0.1-0.5 pc, with future events at ~1000 AU potentially producing measurable electromagnetic signals unlike the 2023 KM3NeT neutrino candidate.
The KM3NeT neutrino event may be a primordial neutrino from relic particle decay or annihilation near recombination, yielding a narrow spectral peak that evades broad power-law constraints from other telescopes.
Sets upper limits on primordial black hole dark matter fraction using extragalactic gamma-ray background, claiming these are the tightest indirect constraints for the mass range.
Minimal UHECR flux models from the Telescope Array predict cosmogenic neutrino fluxes consistent with the KM3-230213A event at the 2σ level.
Updated compilation shows PBHs are tightly constrained across 55 orders of magnitude in mass, ruling out dominant dark matter contributions except in narrow windows, with many limits carrying observational uncertainties.
A Comptonization model of AGN coronae combined with Monte-Carlo photopion production and cosmological evolution can account for IceCube's ~100 TeV and sub-PeV neutrinos using only photohadronic processes.
A review of extreme gamma-ray transients defined as catastrophic events or extreme particle acceleration regimes, covering diagnostics, instruments, and source classes.
Recent high and ultrahigh energy neutrino detections open a new observational window to the universe by revealing sources and processes inaccessible via photons.
Reviews IceCube neutrino results, models Galactic plane flux from cosmic ray interactions with the interstellar medium, and discusses prospects for identifying PeVatrons via LHAASO sources.
citing papers explorer
-
Lights, Camera, Axion: Tracing Axions from Supernovae in the Diffuse $\gamma$-ray Sky
Axions produced in supernovae generate a diffuse gamma-ray signal through conversion in magnetic fields, yielding competitive constraints on the axion-photon coupling from COMPTEL, EGRET, and Fermi-LAT data plus forecasts for future MeV telescopes.
-
Particle Acceleration, Coronal Neutrino Production, and the Diffuse Extragalactic Neutrino Background from Supermassive Black Holes
The cosmologically integrated neutrino emission from supermassive black hole coronae in Seyfert galaxies can account for the sub-PeV diffuse extragalactic neutrino flux observed by IceCube.
-
Non-Thermal Production of Sexaquark Dark Matter
Non-thermal production via late-decaying reheatons can achieve the observed dark matter density for sexaquarks by controlling branching fractions and coalescence probabilities, unlike thermal freeze-out which underproduces them by many orders of magnitude.
-
Muonic Boson Limits: Supernova Redux
Supernova models yield coupling limits g_a ≲ 0.9×10^{-10} and g_φ ≲ 0.4×10^{-10} for masses above 100 keV from gamma-ray observations, plus stronger trapping-regime limits from explosion energy, that are difficult to reconcile with a muon g-2 explanation.
-
The Delta Resonance in the Neutrino Sky
A proton spectrum with index -3.1 interacting with 0.3 keV X-rays via the Delta resonance reproduces the observed 30 TeV neutrino break and limits the accompanying gamma-ray cascade contribution to ~10% of the isotropic background at 3 GeV.
-
Electromagnetic Signatures From Primordial Black Holes in the Solar System
Calculations indicate AMEGO-X could detect PBH transits within 0.1 AU while HAWC and LHAASO could observe explosions out to 0.1-0.5 pc, with future events at ~1000 AU potentially producing measurable electromagnetic signals unlike the 2023 KM3NeT neutrino candidate.
-
The KM3NeT event: a primordial high energy neutrino?
The KM3NeT neutrino event may be a primordial neutrino from relic particle decay or annihilation near recombination, yielding a narrow spectral peak that evades broad power-law constraints from other telescopes.
-
Limits on primordial black holes from the extragalactic gamma-ray background; current status and future projections
Sets upper limits on primordial black hole dark matter fraction using extragalactic gamma-ray background, claiming these are the tightest indirect constraints for the mass range.
-
Ultra-high energy event KM3-230213A as a cosmogenic neutrino in light of minimal UHECR flux models
Minimal UHECR flux models from the Telescope Array predict cosmogenic neutrino fluxes consistent with the KM3-230213A event at the 2σ level.
-
TeV to PeV neutrinos from AGN coronae
A Comptonization model of AGN coronae combined with Monte-Carlo photopion production and cosmological evolution can account for IceCube's ~100 TeV and sub-PeV neutrinos using only photohadronic processes.
-
Extreme Transients in Gamma Rays
A review of extreme gamma-ray transients defined as catastrophic events or extreme particle acceleration regimes, covering diagnostics, instruments, and source classes.
-
Particle Astrophysics with High and Ultrahigh Energy Neutrinos
Recent high and ultrahigh energy neutrino detections open a new observational window to the universe by revealing sources and processes inaccessible via photons.
-
IceCube Results and Perspective for Neutrinos from LHAASO Sources
Reviews IceCube neutrino results, models Galactic plane flux from cosmic ray interactions with the interstellar medium, and discusses prospects for identifying PeVatrons via LHAASO sources.