  Using the Onsager-Machlup functional integral approach, we obtain the work
distribution function and the distribution of the dissipated heat of a Brownian
particle subjected to a confining harmonic potential and an oscillatory driving
force. In the long time limit, the width of the work distribution function
initially increases with the frequency of the driving force and finally
saturates to a fixed value for large values of the angular frequency. Using the
results from the work distribution part, we next obtain the distribution of the
dissipated heat for the equilibrium initial condition. Using the method of
steepest descent, we obtain a Gaussian distribution for small fluctuations in
the large time limit. The distribution function, for a fixed time has been
obtained numerically. It is shown that the heat distribution, in general, does
not satisfy the transient fluctuation theorem.
