Function to fit the light transmitted from a cavity

[kelly0303]

Hello! I measured the light transmitted from a bow-tie cavity (while scanning the cavity length) and the peak obtained while scanning has the shape in the figure below. It is basically a combination of a Lorentzian, with an exponential decay on the right side and some oscillations on top. What function should I use to fit this? Thank you!

 

[Haborix]

There should be a reason for fitting something to curve (unless you just want a pretty smooth line, then just use interpolation). For example, when parameters in the fitting function correspond to physically meaningful parameters. Do you know of any theoretical calculations of the quantity you are plotting? If so, I would plot to the function from that calculation. I'm not very familiar with these devices, so I can't be much help beyond that.