Electron impact excitation of H2 - Rydberg band systems and the benchmark dissociative cross section for H Lyman-alpha

Journal Article · Sun Sep 01 00:00:00 EDT 1985 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/163493· OSTI ID:5611475

Shemansky, D E; Hall, D T; Ajello, J M

The cross sections sigma R 1 (2p) for excitation of H Ly-alpha emission produced by electron impact on H2 is reexamined. A more accurate estimate for sigma R 1 (2p) is obtained based on Born approximation estimates of the H2 Rydberg system cross sections using measured relative excitation functions. The obtained value is (8.18 + or -1.2) x 10 to the -18th sq cm at 100 eV, a factor of 0.69 below the value universally applied to cross section measurements over the past decade. Cross sections for the H2 Rydberg systems fixed in magnitude by the Born approximation have also been obtained using experimentally determined excitation functions. Accurate analytic expressions for these cross sections allow the direct calculation of rate coefficients. 30 references.

• Research Organization: Arizona Univ., Tucson; California Institute of Technology, Pasadena
• OSTI ID: 5611475
• Journal Information: Astrophys. J.; (United States), Vol. 296
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ELECTRON-MOLECULE COLLISIONS
EXCITATION
HYDROGEN
LYMAN LINES
RYDBERG STATES
ULTRAVIOLET SPECTRA
COLLISIONS
ELECTRON COLLISIONS
ELEMENTS
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITED STATES
MOLECULE COLLISIONS
NONMETALS
SPECTRA
640304* - Atomic
Molecular & Chemical Physics- Collision Phenomena