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arXiv · 2506.18500

Towards a TeV blazar sequence and its physical interpretation

I. Viale·E. Prandini·C. Righi·F. Bovolon·N. Sahakyan
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Abstract

Blazars, a highly energetic subclass of jetted active galactic nuclei, show a broad band spectral energy distribution (SED) with two bumps, resulting from non-thermal jet emission. In 1998, an anticorrelation between the SED luminosity and the peaks frequency was found, later confirmed in 2017, called the blazar sequence. Its origin is still unclear. This work is part of a broader effort aiming at giving a physical interpretation to the blazar sequence, by modeling the sources emission in a Synchrotron Self Compton framework, concentrating only on TeV-detected blazars of BL Lac type. Unlike the original sequence, sources were binned by synchrotron peak frequency. The SED of one representative source is modeled for each bin, using data from average activity state to ensure consistency. Here, we focus on the study of one of the selected representative sources, PKS 2155-304, a high-energy-peaked BL Lac, showing the performed data selection and preliminary modeling results.

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I. Viale, E. Prandini, C. Righi, F. Bovolon, N. Sahakyan. 2025-06-23. Towards a TeV blazar sequence and its physical interpretation. https://arxiv.org/abs/2506.18500

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