Ponente
Descripción
Extreme high-synchrotron peaked blazars (EHSPs), defined by
synchrotron peak frequencies exceeding 10^{17} Hz, represent a particularly elusive and energetic subclass of blazars. Their spectral properties challenge standard emission models and offer valuable constraints on particle acceleration processes in relativistic jets. In this work, we present a systematic study of 124 gamma-ray blazars selected for high synchrotron peaks and low variability. Using multi-wavelength data from Swift-UVOT/XRT, Fermi-LAT, and archival observations via the SSDC SED Builder, we model their spectral energy distributions with a one-zone synchrotron/synchrotron-self-Compton framework. We identify 66 new EHSP candidates, significantly enlarging the known sample. A clear correlation emerges between synchrotron peak frequency and the magnetic-to-kinetic energy density ratio, with the most extreme EHSPs approaching equipartition. This indicates that as the synchrotron peak shifts to higher frequencies, the energy stored in the magnetic field
becomes comparable to that of the radiating electrons, pointing to a more balanced and energetically efficient jet configuration in the most extreme sources. We also confirm that the synchrotron peak frequency is inversely correlated with Compton dominance, consistent with expectations from the blazar sequence. Finally, we assess detectability with CTAO and identify up to nine EHSPs that could be detected at >5σ in
20-hour exposures, supporting targeted follow-up by next-generation TeV observatories.
