CNN emulator for decaying magnetic field fast-cooling synchrotron spectra is trained on synthetic data and used in Bayesian fits to GRB 231020A, favoring the decaying-field model over the standard version.
Unsteady Outflow Models for Cosmological Gamma-Ray Bursts
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
The 'event' that triggers a gamma ray burst cannot last for more than a few seconds. This is, however, long compared with the dynamical timescale of a compact stellar-mass object ($\sim 10^{-3}$ seconds). Energy is assumed to be released as an outflow with high mean lorentz factor $\Gamma$. But a compact stellar-mass collapse or merger is, realistically, likely to generate a mass (or energy) flux that is unsteady on some timescales in the range $10^{-3}$ - 10 seconds. If $\Gamma$ fluctuates by a factor of $\sim 2$ around its mean value, relative motions within the outflowing material will themselves (in the comoving frame) be relativistic, and can give rise to internal shocks. For $\Gamma \sim 10^2$, the resultant dissipation occurs outside the 'photosphere' and can convert a substantial fraction of the overall outflow energy into non-thermal radiation. This suggests a mechanism for cosmological bursts that demands less extreme assumptions (in respect of $\Gamma$-values, freedom from baryonic contamination, etc) than earlier proposals.
years
2026 4representative citing papers
Realistic GRB parameters weaken previous ALP cooling bounds, but ALP-induced secondary fireballs in GRBs could still be probed via isotropic X-ray emission from future telescopes.
Time lags between energy bands serve as proxies for spectral evolution in GRBs, with positive lags tracing prompt emission softening and negative lags indicating a new delayed high-energy component.
GRB 250424A afterglow shows simultaneous shallow decay in X-ray and optical bands modeled as continuous energy injection (q≈0.34) into a forward shock in constant-density medium, with E_K,iso ≈5.5×10^52 erg and no clear supernova component.
citing papers explorer
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Modeling Gamma-Ray Burst Spectra with Convolutional Neural Networks: Fast-Cooling Synchrotron Emission in a Decaying Magnetic Field
CNN emulator for decaying magnetic field fast-cooling synchrotron spectra is trained on synthetic data and used in Bayesian fits to GRB 231020A, favoring the decaying-field model over the standard version.
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Reappraisal of the Constraints on Heavy Axion-like Particles from Gamma-Ray Bursts
Realistic GRB parameters weaken previous ALP cooling bounds, but ALP-induced secondary fireballs in GRBs could still be probed via isotropic X-ray emission from future telescopes.
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Time lags as proxy of spectral evolution in gamma-ray bursts
Time lags between energy bands serve as proxies for spectral evolution in GRBs, with positive lags tracing prompt emission softening and negative lags indicating a new delayed high-energy component.
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GRB 250424A: A Case Study of Energy Injection with Multiwavelength Observations
GRB 250424A afterglow shows simultaneous shallow decay in X-ray and optical bands modeled as continuous energy injection (q≈0.34) into a forward shock in constant-density medium, with E_K,iso ≈5.5×10^52 erg and no clear supernova component.