Absolute doubly differential cross sections for ejection of secondary electrons from gases by electron impact. II. 100-500-eV electrons on neon, argon, molecular hydrogen, and molecular nitrogen

Journal Article · Wed Mar 01 04:00:00 EST 1978 · Phys. Rev., A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.17.843· OSTI ID:7276569

DuBois, R D; Rudd, M E

Absolute doubly differential cross sections for secondary electron production by electron impact have been measured for static gas targets of neon, argon, hydrogen, and nitrogen. Electron impact energies were from 100 to 500 eV. An electrostatic analyzer was used to analyze secondary electrons with energies between 4 eV and the primary electron energy minus the first ionization potential of the target. Angles of emission were 10/sup 0/ to 150/sup 0/. The present data agree well with the data of Opal, Beaty, and Peterson at 90/sup 0/ but, as was observed previously for helium, the agreement becomes increasingly poorer for larger and smaller angles. This angular disagreement, which is independent of target gas and impact energy, is approximately given by a + (1-a) sin theta, where a = 0.10 +- 0.12. Previously we compared the experimental data of Opal, Beaty, and Peterson with calculations by Manson for helium and obtained a similar correction but with a = 0.53. Recent Born-approximation calculations of Manson are compared with our 500-eV argon data. The calculations reproduce the angular distributions of the measured cross sections quite well for small secondary-electron energies. For intermediate energies the agreement is still quite good near the momentum-conservation peak but poorer for large scattering angles.

• Research Organization: Behlen Laboratory of Physics, University of Nebraska, Lincoln, Nebraska 68588
• OSTI ID: 7276569
• Journal Information: Phys. Rev., A; (United States), Journal Name: Phys. Rev., A; (United States) Vol. 17:3; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ARGON
ATOM COLLISIONS
COLLISIONS
CROSS SECTIONS
CRYOGENIC FLUIDS
DIFFERENTIAL CROSS SECTIONS
ELECTRON COLLISIONS
ELECTRON-ATOM COLLISIONS
ELECTRON-MOLECULE COLLISIONS
ELEMENTS
FLUIDS
HYDROGEN
IONIZATION
MOLECULE COLLISIONS
NEON
NITROGEN
NONMETALS
RARE GASES