  We present calculations of Majorana edge modes in cylindrical nanowires of a
semiconductor material with proximity-induced superconductivity. We consider a
Rashba field along the transverse direction and an applied magnetic field in
arbitrary orientation. Our analysis is based on exact numerical
diagonalizations for the finite cylinder and on the complex band structure for
the semi-infinite one. Orbital effects are responsible for a strong anisotropy
of the critical field for which the effective gap vanishes. Robust Majorana
modes are induced by the parallel field component and we find regimes with more
than one Majorana mode on the same edge. Experimentally, they would manifest as
a specific sequence of zero-bias conductances as a function of magnetic field.
In the finite cylinder, a degradation of the Majorana modes due to interference
of the two edges leads to oscillating non zero energies for large enough
fields.
