Accession Number:

ADA142161

Title:

Measurement of Lifetimes of the Vibrational Levels of the B State of N2.

Descriptive Note:

Final rept. 1 Apr 82-30 Sep 83,

Corporate Author:

HARVARD UNIV CAMBRIDGE MASS DEPT OF PHYSICS

Personal Author(s):

• Pipkin,F. M.

Report Date:

1984-01-21

Pagination or Media Count:

39.0

Abstract:

This report summarizes two series of investigations of molecular nitrogen. In the first series of experiments the lifetimes of selected levels of the B 3 pi g state of N2 were measured. A chopped cw dye laser beam was employed to excite selected levels of the B 3 pi g state of N2 in a beam of molecules in the A 3 sigma u metastable state. Laser induced fluorescence was observed from the vibrational levels nu 5 through nu 12, and a photomultiplier was used in conjunction with a microcomputer system to measure the time dependence of the decay light. The lifetimes which were measured to an accuracy of 3 showed a smooth decline from 5.8 microsec for nu 5 to 4.11 microsec for nu 12. No dependence on rotational level was observed. In the second series of experiments an attempt was made to produce a beam of metastable N2 molecules in the a 1 sigma g state, use a dye laser to excite them to the c4o1 pi u and c5o1 sigma u metastable states, and observe the fluorescent radiation. Author

Descriptors:

• *VIBRATION
• *LIFE EXPECTANCY(SERVICE LIFE)
• *MOLECULAR STATES
• *NITROGEN
• TIME DEPENDENCE
• LASER INDUCED FLUORESCENCE
• EXCITATION
• LIGHT
• MOLECULAR BEAMS
• DYE LASERS
• ROTATION
• DECAY
• METASTABLE STATE

Subject Categories:

• Nuclear Physics and Elementary Particle Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE