On the definition of width in Doppler broadening problems.

AI Thread Summary
The discussion centers on confusion regarding the definition of "Doppler width" in the context of Doppler broadening problems. Participants express uncertainty about which formula to apply, noting that frequencies have various width definitions due to their distribution. A standard notion for Doppler width is questioned, with the suggestion that the appropriate formula may depend on the specific context of the problem. One participant confirms using a referenced formula but still does not arrive at the correct answer. The conversation highlights the need for clarity on Doppler width definitions and their application in different scenarios.
Isomorphism
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The following question has stumped me. I am not getting the answer marked. Instead I am getting option a). I have produced my attempt below.

Also I have no idea which formula to use when the question says Doppler width. Since frequencies form a distribution, there are multiple notions of width. Is there a standard notion for the term Doppler width in broadening problems?

IMG_0823.JPG


Thanks
 
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Isomorphism said:
The following question has stumped me. I am not getting the answer marked. Instead I am getting option a). I have produced my attempt below.

Also I have no idea which formula to use when the question says Doppler width. Since frequencies form a distribution, there are multiple notions of width. Is there a standard notion for the term Doppler width in broadening problems?
You use the one most appropriate to the context.
Have you seen: http://hyperphysics.phy-astr.gsu.edu/hbase/atomic/broaden.html
 
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Simon Bridge said:
You use the one most appropriate to the context.
Have you seen: http://hyperphysics.phy-astr.gsu.edu/hbase/atomic/broaden.html

Yes I have. I have used that formula on the left side of my workout. The answer is not there among the options.
 
I see what you mean. It will have to depend on the course the test was for.
 
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