Quasiparticle picture for the de Haas-van Alphen effect

Physical argumen s are given for the quasiparticle behavior observed in the de Hass-van Alphen effect. An upper limit to the maximum deviation from quasiparticle behavior which may be observed is given and the asymptotic behavior as $T\to 0$ is derived. These results indicate why the deviations from quasiparticle behavior might appear small, even for large magnetic fields. Misinterpretations of earlier work are clarified and an application of the picture to experiments on nearly ferromagnetic palladium-nickel alloys is made.