Role of long-lived N-2(X-1 Sigma(+)(g), upsilon) molecules and N-2(A(3)Sigma(+)(u)) and N-2(a'(1)Sigma(-)(u)) states in the light emissions of an N-2 afterglow

• Type: Article in International Scientific Journal
• Date: 2001

Authors

Loureiro, J (Author) Other; P. A . Sá (Author) FEUP; Guerra, V (Author) Other

Journal

Title: Journal of Physics D: Applied Physics

Vol. 34 No. 12

Pages: 1769-1778

ISSN: 0022-3727

Publisher: Institute of Physics Publishing

Indexing

ISI Web of Knowledge - 50 Citations

Scopus - 56 Citations

Other information

Authenticus ID: P-000-V6G

DOI: 10.1088/0022-3727/34/12/303

Abstract (EN): The enhancement of N-2(B (3) Pi (g)) and N-2(+)(B (2) Sigma (+)(u)) states, responsible by the emission bands for the 1(+) and 1(-) systems of N-2, in the short-lived afterglow of a flowing N-2 microwave discharge at omega/(2 pi) = 433 MHz is investigated by modelling. It is shown that pronounced maxima for both emissions are obtained downstream from the discharge by assuming the formation of N-2(A (3) Sigma (+)(u)) and N-2(a' (1) Sigma (-)(u)) states by collisions of N-2 (X (1) Sigma (+)(g), upsilon) molecules in highly vibrational levels with N(S-4) atoms. Other channels that can also produce the emissions are investigated as well, but the common factor in all of them is the role played by the vibrationally excited N-2(X,upsilon) molecules in levels > 35. During the relaxation process a pumping-up effect for the vibrational quanta at the higher vth levels occurs as a result of near-resonant V-V energy-exchange collisions, that produces a rise in the observed peaks for the N-2 electronic states in the flowing afterglow.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10