Hello, i hope i posted this in the correct forum! When measuring coherence of a HeNe laser using a Michelson interferometer, there are key points along the moving interferometer arm where coherence is highest. The distance between each of these peaks corresponds with the length of the laser cavity. Based on your knowledge of gas laser fundamentals, why is this the case? I can't find anything online to answer this question and was hoping someone here might know. Thank you for helping, it means a lot!