Comment on ``Activation Gaps and Mass Enhancement of Composite   Fermions''
  In a recent Letter (Phys. Rev. Lett. 81, 4200 (1998)) Park and Jain presented results of gap calculations for polarized states at \nu=1/3, 2/5, 3/7 and 4/9. They computed the effects on the gaps due the finite width of the interfacial wave function (wf). In this Comment, it is shown that the reduction of the gaps due to the finite width of the wf is overestimated by about a factor of two. The agreement between theoretical and experimental gap values cannot be taken seriously, but results from an incorrect determination of the width parameter. 
Rudolf H. Morf (Paul Scherrer Institute, Villigen, Switzerland)