  We present a microscopic theory of the collective modes of a ``smooth'' edge
of a quantum Hall system, showing under what conditions these modes can be
described as a set of independent bosons. We then calculate the electronic
spectral function in an independent-boson model - a procedure that reduces to
standard bosonization in the limit of ``sharp'' edge. The I-V tunneling
characteristics deduced from this model exhibit, for low voltage, a power law
behavior, with exponents that differ significantly from those of the sharp edge
model.

Condensed Matter