I have to fit a gaussian curve convoluted with an expoential tail to the attached data. For the curve i have the below equation but it does not produce the desired shape. The attached image shows the curve shape I am aiming to achieve using these values and curve equation the exponential section dominates such that the gaussian component cannot even be seen. How would i go about getting the desired curve shape?
where a is a place holder for the decay constant (it may be the issue if it is a very incorrect guess but i am unsure) and o is teh standard deviation of the data.