VLBA18A-075

Probing the polarized innermost structure of the relativistic jet of 4C+01.28

Abstract

We want to probe the polarized fine structure of the nuclear region of the blazar 4C+01.28 (B1055+018, J1058+015) by combining (granted) 1.3-mm EHT+ALMA observations with 3mm and 7mm HSA observations. 4C +01.28 has a mm flux density over 3 Jy, highly variable up to high energies (it shows even gamma-variability down to 3-hr time scales). Recent GMVA 3-mm results show a compact polarized core with a faint relativistic jet. At cm-wavelengths, its polarized structure consists of a two-component structure, with an inner spine with a transverse B-field and a distinct boundary layer (the sheath) with a longitudinal B field. We aim for deep polarization images of the stratified jet at scales of 200uas to 30uas resolution, probing uniquely whether the spine-sheath structure extends to jet base and testing, on scales of 1200 R_s, the different MHD jet formation models: Blandford-Payne, where the jet is anchored to magnetized rotating disks, should result in an edge-brightened polarisation up to the base of the jet; or Blandford-Znajek, where the jet is driven by the BH spin, result in a more compact footprint of the jet, which implies a higher opacity and a smaller polarisation degree.

Investigators

Name	Institution
Michael Kreter	Würzburg, Universität
Shep Doeleman	Haystack Observatory
Sera Markoff	Amsterdam, Universiteit van
Remo Tilanus	Arizona, University of
Roberto Angioni	Max-Planck-Institut für Radioastronomie
Ivan Marti-Vidal	València, Universitat de
Ruben Herrero-Illana	European Southern Observatory
Jose Guirado	València, Universitat de
Juan-Maria Marcaide	València, Universitat de
Miguel Perez-Torres	Andalucía, Instituto de Astrofísica de
Rebecca Azulay	València, Universitat de
Anne-Kathrin Baczko	Max-Planck-Institut für Radioastronomie; Chalmers University Of Technology
Tony Zensus	National Radio Astronomy Observatory; Max-Planck-Institut für Radioastronomie
Jose L. Gomez	Andalucía, Instituto de Astrofísica de
Svetlana Jorstad	Boston University
Alan Marscher	Boston University
Matthias Kadler	Würzburg, Universität
Thomas Krichbaum	Max-Planck-Institut für Radioastronomie
Eduardo Ros	Max-Planck-Institut für Radioastronomie; València, Universitat de
Antonio Alberdi *	Andalucía, Instituto de Astrofísica de
GBT Operator	Green Bank Observatory

* indicates the PI