The Ai and A 2 transitions, which delineate the A\ phase of superfluid 3 He, are measured in magnetic fields up to 3 T over a wide range of pressures. At zero pressure the A\-A 2 splitting is found to be smaller than at melting pressure by a factor of 5. Strong-coupling effects are similarly smaller by an order of magnitude.

We present experimental evidence for / : wave pair interactions in superfluid 3 He-A These interactions cause the frequency of the clapping mode to be significantly reduced relative to the value expected in a pure axial state, at temperatures arbitrarily close to T c . We find that the predicted /wave transition temperature in the absence of/>wave pairing is 0.2-0.3 times the observed T c .