The structure and kinematics of the HH 444 photoionized jet in the σ Orionis region L. López-Martín, A. C. Raga, J. A. López and J. Meaburn A&A, 371 3 (2001) 1118-1122 Published online: 15 June 2001 DOI: 10.1051/0004-6361:20010373