The polarized target of the Spin Muon Collaboration at CERN was used for de
ep inelastic muon scattering experiments during 1993-1996 with a polarized
muon beam to investigate the spin structure of the nucleon. Most of the exp
eriments were carried out with longitudinal target polarization and 190 GeV
muons, and some were done with transverse polarization and 100 GeV muons.
Protons as well as deuterons were polarized by dynamic nuclear polarization
(DNP) in three kinds of solid materials - butanol, ammonia, and deuterated
butanol - with maximum degrees of polarization of 94%, 91% and 60%, respec
tively. Considerable attention was paid to the accuracies of the NMR polari
zation measurements and their analyses, the accuracies achieved were betwee
n 2.0% and 3.2%. The SMC target system with two cells of opposite polarizat
ions, each cell 65 cm long and 5 cm in diameter, constitutes the largest po
larized target system ever built and facilitates accurate spin asymmetry me
asurements. The design considerations, construction and performance of the
target are reviewed, (C) 1999 Elsevier Science B.V. All rights reserved.