Determination of betatron tunes, Twiss parameters and sum and difference coupling coefficients with an AC dipole

The control of the mechanical and dynamic aperture of the LHC requires a tight control of linear optics parameters such as the tune, the beta-functions and the linear coupling resonance driving terms. This report presents a non-standard measurement method of these parameters based on a transverse excitation of the beam in "AC-dipole" mode, that is at one or several frequencies close to but outside the eigenfrequency spectrum of the beam. After having derived the general expression of the beam response in four dimensions, the measurement protocol and different possible hardware configurations will be described and simulation results obtained for the LHC will be presented.