|Author||Rubin, K. ♦ Perel, J. ♦ Bederson, B.|
|Source||United States Department of Energy Office of Scientific and Technical Information|
|Subject Keyword||PHYSICS ♦ ANGULAR DISTRIBUTION ♦ ATOMS ♦ BEAMS ♦ CROSS SECTIONS ♦ DIAGRAMS ♦ ELECTRON BEAMS ♦ ENERGY ♦ ENERGY RANGE ♦ FILTERS ♦ MAGNETIC FIELDS ♦ MEASURED VALUES ♦ OPTICAL SYSTEMS ♦ POLARIZATION ♦ POTASSIUM ♦ RECOILS ♦ SCATTERING ♦ VELOCITY|
|Abstract||An atom beam recoil technique was used to determine the total, Q, differential, sigma ( theta ), and differential exchange, sigma /sub e/, cross sections for the scattering of low-energy electrons by potassium. The method consists of observing the angular distribution of atoms scattered from a potassium atom beam which was cross fired by an electron beam. Relative values of sigma ( theta ) are then obtained by transforming to electron scattering angles. An inhomogeneous magnet and collimating channel are used as a velocity filter for the atom beam. Curves representing the variation of sigma ( theta ) with theta between approximately 15 ction prod- and 60 ction prod- are presented for various electron energies between 0.6 and 9.0 ev. The magnet also serves to polarize the beam. Relative values of sigma /sub e/( theta ) were determined by observing the amount of depolarization of the beam in the scattering region, using a second inhomogeneous magnet as an analyzer. Over the observed range of angles, exchange accounts for approximately one third of the scattering. Bounds on the total exchange cross section, Q/sub e/, are also tabulated for energies between 0.5 and 4.0 ev. The bounds on Q/sub e/ at 0.5 volt are 0.8 x 10/sup -14/ cm/sup 2/ <Q/sub e/ < 1.6 x 10/sup -14/ cm/sup 2/. (auth)|
|Learning Resource Type||Article|
|Publisher Department||New York Univ.|
|Organization||New York Univ.|
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