A Multiwavelength Spectral and Polarimetric Study of the Jet of 3C 264

TL;DR

This study provides a detailed multiband spectral and polarimetric analysis of the 3C 264 jet, revealing spectral curvature, magnetic field structure, and X-ray emission mechanisms, offering insights into jet physics and particle acceleration.

Contribution

It offers the first comprehensive multiwavelength spectral and polarimetric analysis of 3C 264's jet, highlighting spectral curvature, magnetic field complexity, and synchrotron X-ray emission mechanisms.

Findings

Spectral curvature from near-IR to UV indicates velocity/magnetic field gradients.

Magnetic field structure is smooth but shows complex features linked to spectral changes.

X-ray emission is confirmed to be synchrotron in origin.

Abstract

We present a comprehensive multiband spectral and polarimetric study of the jet of 3C 264 (NGC 3862). Included in this study are three HST optical and ultraviolet polarimetry data sets, along with new and archival VLA radio imaging and polarimetry, a re-analysis of numerous HST broadband data sets from the near infrared to the far ultraviolet, and a Chandra ACIS-S observation. We investigate similarities and differences between optical and radio polarimetry, in both degree of polarization and projected magnetic field direction. We also examine the broadband spectral energy distribution of both the nucleus and jet of 3C 264, from the radio through the X-rays. From this we place constraints on the physics of the 3C 264 system, the jet and its dynamics. We find significant curvature of the spectrum from the near-IR to ultraviolet, and synchrotron breaks steeper than 0.5, a situation also encountered in the jet of M87. This likely indicates velocity and/or magnetic field gradients and more efficient particle acceleration localized in the faster/higher magnetic field parts of the flow. The magnetic field structure of the 3C 264 jet is remarkably smooth; however, we do find complex magnetic field structure that is correlated with changes in the optical spectrum. We find that the X-ray emission is due to the synchrotron process; we model the jet spectrum and discuss mechanisms for accelerating particles to the needed energies, together with implications for the orientation of the jet under a possible spine-sheath model.