Radio galaxies and magnetic fields in A514

¹ Dipartimento di Astronomia, Univ. Bologna, Via Ranzani 1, 40127 Bologna, Italy
² Istituto di Radioastronomia -CNR, via Gobetti 101, 40129 Bologna, Italy
³ National Radio Astronomy Observatory, Socorro, NM 87801, USA
⁴ Dipartimento di Fisica, Univ. Bologna, Via B. Pichat 6/2, 40127 Bologna, Italy

Corresponding author: F. Govoni, fgovoni@ira.bo.cnr.it

Received: 12 June 2001
Accepted: 21 September 2001

Abstract

A514 contains six extended and polarized radio sources located at various projected distances from the cluster center. Here we present a detailed study of these six radio sources in total intensity and polarization using the Very Large Array at 3.6 and 6 cm. Since the radio sources sample different lines of sight across the cluster, an analysis of the Faraday Rotation Measures (RMs) provides information on the strength and the structure of the cluster magnetic field. These sources show a decreasing Faraday Rotation Measure with increasing distance from the cluster center. We estimate the strength of the magnetic field to be ~3-7 μG in the cluster center. From the RM structure across the stronger and more extended sources we estimate the coherence length of the magnetic field to be about 9 kpc at the cluster center.