  The evolution of the magnetic excitation spectrum of the unconventional
superconductor CeCoIn$_{5}$ was studied by inelastic neutron scattering as a
function of magnetic field applied in the [1, -1, 0] direction. The spin
resonance characteristic of the superconducting states was observed up to about
$H_{c2}$/2 : it is still centered at (1/2, 1/2, 1/2) when the magnetic field
increases while its characteristic energy decreases and its lineshape
substantially broadens.
