The Ginzburg-Landau theory of superconductivity is examined in the case of
a special geometry of the sample, the infinite cylinder. We restrict to axi
ally symmetric solutions and consider models with and without vortices. Fir
st putting the Ginzburg-Landau parameter kappa formally equal to infinity,
the existence of a minimizer of this reduced Ginzburg-Landau energy is prov
ed. Then asymptotic behaviour for large kappa of minimizers of the full Gin
zburg-Landau energy is analyzed and different convergence results are obtai
ned. Our main result states that, when kappa is large, the minimum of the e
nergy is reached when there are about kappa vortices at the center of the c
ylinder. Numerical computations illustrate the various behaviours. (C) Else
vier, Paris.