UDF program for gaussian distribution in space, time and both
 

I'm a beginner in ANSYS Fluent. I don't have any experience in udf programming for a 3D-model (Transient). I need to create a UDF for gaussian distribution in the following:-
1) space domain,
2) time domain,
3) Space and time domain.
The problem is of pulsed beam having delta t = 0.5 msec, T = 40 msec, Peak power = 90 kW, Avg Power = 1125 W, Duty cycle = 1.25%.

I tried to go through various udf programs but I'm unable to understand them with respect to my specific problem.

Kindly help me out.

Thanks!