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Electron/neutron scatter

  1. Jun 4, 2009 #1
    Question: Does the dimensionless quantity derived from the constants below have any physical meaning?

    6.6524585580E-29 = Thomson cross section in SI units
    2.1001941382E-16 = neutron Compton wavelength / 2pi inSI units
    1508.215132 = (Thomson cross section) * (neutron Compton wavelength / 2pi)^-2

    Regards,
    Krakers
     
  2. jcsd
  3. Jun 4, 2009 #2

    malawi_glenn

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    Can you argue why it should have a meaning?
     
  4. Jun 4, 2009 #3

    clem

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    No......................
     
  5. Jun 4, 2009 #4
    Maybe because:
    [tex]\frac{55+150 \pi+1867 \pi^2}{4 \pi} = 1508.215132...[/tex]

    ;)
     
  6. Jun 4, 2009 #5

    clem

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    Now I get it. Do you have software that does that for you?
     
  7. Jun 5, 2009 #6
  8. Jun 5, 2009 #7
    The Thomson cross section (= 8 pi r02/3 = 0.66 barns) is the low energy limit of the total Compton cross section (photon scattering on free electrons). r0 is the classical electron radius (2.828 fermi).
     
  9. Jun 8, 2009 #8
    The dimensionless quantity above is equal to [tex]\frac{8\pi}{3} (\alpha \frac{m_n}{m_e} )^2[/tex].
     
  10. Jun 9, 2009 #9
    Thank you all for your time and the gift of your knowledge.

    Regards,
    Krakers
     
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