The magnetic precursor of L1448-mm: excitation differences between ion and neutral fluids J. F. Roberts, I. Jiménez-Serra, J. Martín-Pintado, S. Viti, A. Rodríguez-Franco, A. Faure and J. Tennyson A&A, 513 (2010) A64 Published online: 30 April 2010 DOI: 10.1051/0004-6361/200913086