The Cygnus Bubble's ultra-high-energy gamma-ray emission above 400 TeV is physically more consistent with a microquasar halo around Cygnus X-3 than with the Cygnus OB2 star-forming region.
Cygnus X-3: A variable petaelectronvolt gamma-ray source
7 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
We report the discovery of variable $\gamma$-rays up to petaelectronvolt from Cygnus X-3, an iconic X-ray binary. The $\gamma$-ray signal was detected with a statistical significance of approximately 10 $\sigma$ by the Large High Altitude Air Shower Observatory (LHAASO). Its intrinsic spectral energy distribution (SED), extending from 0.06 to 3.7 PeV, shows a pronounced rise toward 1 PeV after accounting for absorption by the cosmic microwave background radiation. We find variability on month-long timescales at a significance of $8.6 \sigma$, coinciding with a high state of the GeV gamma-ray flux detected by the Fermi-LAT. This,together with a 3.2$\sigma$ evidence for orbital modulation, suggests that the PeV $\gamma$-rays originate within, or in close proximity to, the binary system itself. The observed energy spectrum and temporal modulation can be naturally explained by $\gamma$-ray production through photomeson processes in the innermost region of the relativistic jet, where protons need to be accelerated to tens of PeV energies.
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background 2representative citing papers
Derives series solution for two-zone cosmic-ray diffusion and finds local-source probability at 10 TeV rises from 0.4% to 1.7-2.2% but remains model-dependent.
17-year Fermi-LAT observations detect GeV excesses in SS 433's W50 nebula whose spectra and positions suggest acceleration of cosmic-ray protons in microquasar outflows, potentially the first such evidence.
GRB 221009A exhibits a TeV spectral downturn explained by neutron-induced synchrotron photons as a prompt emission echo, while intergalactic cascades are suppressed for typical filament magnetic fields above 1 nG.
The GeV emission zone in Cygnus X-3 is too large and magnetized too weakly to accelerate protons to PeV energies, so the PeV gamma rays must originate from a more compact inner region with rapid magnetic field dissipation.
A review of extreme gamma-ray transients defined as catastrophic events or extreme particle acceleration regimes, covering diagnostics, instruments, and source classes.
citing papers explorer
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Microquasar Cygnus X-3 as the PeVatron powering the Cygnus Bubble
The Cygnus Bubble's ultra-high-energy gamma-ray emission above 400 TeV is physically more consistent with a microquasar halo around Cygnus X-3 than with the Cygnus OB2 star-forming region.
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On the Contribution of Local Sources to the Galactic Cosmic-Ray Spectrum: An Exact Series Solution for Two-Zone Diffusion
Derives series solution for two-zone cosmic-ray diffusion and finds local-source probability at 10 TeV rises from 0.4% to 1.7-2.2% but remains model-dependent.
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GeV emission around SS 433 with 17 years Fermi-LAT observation
17-year Fermi-LAT observations detect GeV excesses in SS 433's W50 nebula whose spectra and positions suggest acceleration of cosmic-ray protons in microquasar outflows, potentially the first such evidence.
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Multi-TeV $\gamma$-ray candidates from GRB 221009A: a downturn in the intrinsic $\gamma$-ray spectrum, an echo of the prompt emission phase, and intergalactic electromagnetic cascades
GRB 221009A exhibits a TeV spectral downturn explained by neutron-induced synchrotron photons as a prompt emission echo, while intergalactic cascades are suppressed for typical filament magnetic fields above 1 nG.
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Constraining the PeV gamma-ray emission zone of Cygnus X-3 with contemporaneous GeV timing and spectral observations
The GeV emission zone in Cygnus X-3 is too large and magnetized too weakly to accelerate protons to PeV energies, so the PeV gamma rays must originate from a more compact inner region with rapid magnetic field dissipation.
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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.
- Suppressed diffusion and gamma-ray emission from the Cygnus bubble