Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

About scattering length

  1. Mar 26, 2015 #1


    User Avatar

    Hi all,
    I am reading some materials on the scattering. There is simple model to consider atom as a rigid body but with radius replaced by the so-called scattering length. I didn't learn the scattering theory systematically but my understanding on the scattering length is the minimum separation between two atoms when the scatter or interaction becomes significant. I do some research on some typical atoms like sodium. But what confusing me is the article gives 2 scattering length labeled as ##a_{1,-1}## and ##a_{2,2}##, which both are in some unit of ##a_0##. So why there are two different scattering length? Is ##a_0## the bohr radius?
  2. jcsd
  3. Mar 27, 2015 #2


    User Avatar
    Science Advisor
    Gold Member
    2017 Award

    As any physically relevant quantity on scattering, the scattering length is a parameter derived from the S-matrix. It characterizes low-energy (long-wavelength) scattering on a short-ranged potential. For first details, see the pretty good Wikipedia article:
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook