A Modified Synchrotron Model for Knots in the M87 Jet

TL;DR

This paper introduces a modified synchrotron model that explains the broadband spectra of knots in the M87 jet by considering multiple particle acceleration sources, predicting spectral breaks and providing insights into jet properties.

Contribution

The paper presents a novel synchrotron model incorporating multiple acceleration sources to explain the spectral features of M87 jet knots, including spectral breaks and fluxes.

Findings

Model successfully explains radio to X-ray fluxes of knots

Predicts two spectral break frequencies in the knots

Suggests certain knots are unlikely TeV emission sources

Abstract

For explaining the broadband spectral shape of knots in the M87 jet from radio through optical to X-ray, we propose a modified synchrotron model that considers the integrated effect of particle injection from different acceleration sources in the thin acceleration region. This results in two break frequencies at two sides of which the spectral index of knots in the M87 jet changes. We discuss the possible implications of these results for the physical properties in the M87 jet. The observed flux of the knots in the M87 jet from radio to X-ray can be satisfactorily explained by the model, and the predicted spectra from ultraviolet to X-ray could be further tested by future observations. The model implies that the knots D, E, F, A, B, and C1 are unlikely to be the candidate for the TeV emission recently detected in M87.