  We report detailed investigation of quantum oscillations in Sr3Ru2O7,
observed inductively (the de Haas-van Alphen effect) and thermally (the
magnetocaloric effect). Working at fields from 3 T to 18 T allowed us to
straddle the metamagnetic transition region and probe the low- and high-field
Fermi liquids. The observed frequencies are strongly field-dependent in the
vicinity of the metamagnetic transition, and there is evidence for magnetic
breakdown. We also present the results of a comprehensive rotation study. The
most surprising result concerns the field dependence of the measured
quasiparticle masses. Contrary to conclusions previously drawn by some of us as
a result of a study performed with a much poorer signal to noise ratio, none of
the five Fermi surface branches for which we have good field-dependent data
gives evidence for a strong field dependence of the mass. The implications of
these experimental findings are discussed.
