$JetCurry$ I. Reconstructing Three-Dimensional Jet Geometry from Two-Dimensional Images

TL;DR

This paper introduces JetCurry, a novel algorithm that reconstructs the three-dimensional geometry of AGN jets from two-dimensional images using advanced numerical optimization techniques, aiding in understanding jet structures and magnetic fields.

Contribution

The paper presents JetCurry, a new method combining MCMC and BFGS algorithms to visualize 3-D jet structures from 2-D images, specifically applied to the M87 jet.

Findings

3-D visualization of M87 jet's knot D region aligns with expected magnetic field structures.

JetCurry effectively decomposes 2-D images into 3-D geometries.

Broad consistency with theoretical models of jet magnetic fields.

Abstract

We present a three-dimensional (3-D) visualization of jet geometry using numerical methods based on a Markov Chain Monte Carlo (MCMC) and limited memory Broyden-Fletcher-Goldfarb-Shanno (BFGS) optimized algorithm. Our aim is to visualize the 3-D geometry of an active galactic nucleus (AGN) jet using observations, which are inherently two-dimensional (2-D) images. Many AGN jets display complex structures that include hotspots and bends. The structure of these bends in the jet's frame may appear quite different than what we see in the sky frame, where it is transformed by our particular viewing geometry. The knowledge of the intrinsic structure will be helpful in understanding the appearance of the magnetic field and hence emission and particle acceleration processes over the length of the jet. We present the $JetCurry$ algorithm to visualize the jet's 3-D geometry from its 2-D image. We discuss the underlying geometrical framework and outline the method used to decompose the 2-D image. We report the results of our 3-D visualization of the jet of M87, using the test case of the knot D region. Our 3-D visualization is broadly consistent with the expected double helical magnetic field structure of the knot D region of the jet. We also discuss the next steps in the development of the $JetCurry$ algorithm.