Mon. Not. R. Astron. Soc., 356, 859-871 (2005/January-3)
Spine-sheath polarization structures in four active galactic nuclei jets.
PUSHKAREV A.B., GABUZDA D.C., VETUKHNOVSKAYA Y.N. and YAKIMOV V.E.
Abstract (from CDS):
We present the results of multifrequency (15 + 8 + 5GHz) polarization Very Long Baseline Array (VLBA) observations of the three BL Lacertae objects 0745+241, 1418+546 and 1652+398 together with 5-GHz VLBI Space Observatory Programme (VSOP) observations of 1418+546 and 1.6- and 5-GHz VSOP observations of the blazar 1055+018. The jets of all these sources have polarization structure transverse to the jet axis, with the polarization E vectors aligned with the jet along the jet spine and `sheaths' of orthogonal E vectors at one or both edges of the jet. The presence of polarization aligned with the jet near the `spine' may indicate that the jets are associated with helical B fields that propogate outward with the jet flow; the presence of orthogonal polarization near the edges of the jet may likewise be a consequence of a helical jet B field, or may be owing to an interaction with the ambient medium on parsec scales. We have tentatively detected interknot polarization in 1055+018 with E aligned with the local jet direction, consistent with the possibility that the jet of this source is associated with a helical B field.
magnetic fields - polarization - BL Lacertae objects: general
P.860 : 1419+546 is a misprint for 1418+546.