Effective field theory approach for the M1 properties of A=2 and 3 nuclei

The magnetic moments of 2H, 3He and 3H as well as the thermal neutron capture rate on the proton are calculated using heavy baryon chiral perturbation theory à la Weinberg. The M1 operators have been derived up to N3LO. The nuclear matrix elements are evaluated with the use of wave functions obtained by carrying out variational Monte Carlo calculations for a realistic nuclear Hamiltonian involving high-precision phenomenological potentials like Argonne Av18 and Urbana IX tri-nucleon interactions. We discuss the potential- and cutoff-dependence of the results.