How to perfectly fit exp. data with 5 gaussians


Please read tips for efficient and successful posting and posting code

_ROOT Version:5.34
_Platform:Ubuntu 18.04


My experimental data theoretically consists of 5 gaussians(some of the gaussian peak may be not clear),I want to draw the multi-gaussian-fit specturm and each single gaussina fit function on the same figure.
My code worked well with 3-guassian-fit,but the 5-gaussian-fit did not get reliable result.
Can anyone give a tutorial about multi-gaussian-fit ?Here is the raw data file(100000 events).
data1.txt (770.6 KB)
Thanks a million!

You can use this one if you know the position of peak, modify the amp (amplitude)accordingly:

Thanks a lot, It did work. But the fitting result is not good enough, when the peaks have much overlap.