  The aim of this paper is to determine quantum master and filter equations for
systems coupled to continuous-mode single photon fields. The system and field
are described using a quantum stochastic unitary model, where the
continuous-mode single photon state for the field is determined by a wavepacket
pulse shape. The master equation is derived from this model and is given in
terms of a system of coupled equations. The output field carries information
about the system from the scattered photon, and is continuously monitored. The
quantum filter is determined with the aid of an embedding of the system into a
larger system, and is given by a system of coupled stochastic differential
equations. An example is provided to illustrate the main results.
