Magnetic Field Structure in Relativistic Jets Helen Jermak, Carole Mundell, Iain Steele, Richard Harrison, Shiho Kobayashi, Elina Lindfors, Kari Nilsson and Ulisses Barres de Almeida EPJ Web of Conferences, 61 (2013) 03005 Published online: 09 December 2013 DOI: 10.1051/epjconf/20136103005