Question

what is "Unmodified Line" mean in the Compton Effect?

Answer 1

http://prola.aps.org/abstract/PR/v27/i6/p687_1
http://adsabs.harvard.edu/abs/1926PhRv...27..119W

Answer 2

it's purchase..,

Answer 3

can you give me a description of this unmodified line you speak of?

Answer 4

ok...,

"The unmodified line, in compton effect, is due to the scattering by the whole atom; if electron mass is replaced by the mass of the atom, the shift in the wavelange is very small..."

overall, i got it, but I'm still a little bit confused about what this unmodified line??

Answer 5

have idea?

Answer 6

checking my textbook, i've never seen them use the word "unmodified" before.

Answer 7

take a look

Answer 8

Oh. I got it.

Answer 9

I will use expression 1-18 because it is easier to work with.

We are dealing with quantum physics, so photons have momentum.

During compton scattering, if the incoming photon knocks onto an loosely bound electron, then there will be quite a big recoil on the electron's part, because the mass it small. So, there will be a rather observable change in wavelength of the photon after collision. In fact, the resultant wavelength is longer. This is the modified line the book mentions.

However, when the photon collides with the inner and more strongly bound electron, or hitting the nucleus directly, the whole atom recoils. But due to the large mass of the nucleus, the recoil is very small, and thus there is very little change in wavelength. This is what the book refers to when it mentioned unmodified line.

Kudos to you for being able to read a book off the computer screen.