Jet Power Estimates of FSRQs PKS 1441+25 and Ton 599 from Broadband SED Modeling

TL;DR

This study models the broadband spectral energy distributions of two FSRQs to estimate jet powers, finding that models with intrinsic curvature yield consistent power estimates, highlighting differences from HBLs.

Contribution

It introduces a comparative analysis of particle distribution models for FSRQ jet power estimation, emphasizing the insensitivity to spectral curvature in these sources.

Findings

Jet power estimates are consistent across models with intrinsic curvature.

FSRQ jet powers are less sensitive to particle distribution assumptions than HBLs.

External Compton processes dominate FSRQ emission, affecting spectral curvature dependence.

Abstract

Flat-Spectrum Radio Quasars (FSRQs) are among the most energetic and powerful active galactic nuclei, often exhibiting jet powers comparable to or exceeding the Eddington luminosity. In this work, we performed broadband spectral energy distribution (SED) modeling of two FSRQs PKS 1441+25 and Ton 599, using Swift-XRT/UVOT, NuSTAR, Fermi-LAT and VERITAS observations during 2015 and 2021, respectively. We considered four particle distribution models: a broken power law, a log-parabola, and two energy-dependent models in which either the diffusion or acceleration timescale depends on energy. Our results show that the jet power estimates derived from models with intrinsic curvature, such as the log-parabola and energy-dependent models, are of the same order as those obtained with a broken power-law distribution. This contrasts with the case of High Synchrotron Peaked Blazars (HBLs), where the power estimates can differ by nearly two orders of magnitude between models. We attribute this difference to the lower electron break energies typically observed in FSRQs. Consequently, our findings suggest that, unlike in HBLs, the estimated jet powers in FSRQs are relatively insensitive to the assumed particle energy distribution, reflecting the dominance of external Compton processes and weaker dependence on spectral curvature.