François Remy

The radiative lifetime of the C 3Πu state of N2

New measurements of the radiative lifetime of the C 3Πu state of N2 have been made using the single photon delayed‐coincidence technique. No significant variation of the lifetime with v′ having been found the proposed value is τ = (39.2±3.9)ns. This is in good agreement with published values that we consider as the more reliable ones following the criteria discussed in this paper.

The radiative lifetime of the B2Σ+u state of N+2: A new measurement and a discussion of previous results

Abstract The lifetime of the B 2 Σ + u state of N + 2 has been measured by observing the decay of intensity of the (0-0) band under widely different experimental conditions. The proposed value is τ =(61.5±1.1) ns. The discrepancies among the published values determined by fluorescence decay are probably due to false background estimations in the least-squares fit treatment of data.

Low resolution VUV absorption spectrum of boron monoxide

The absorption spectrum of BO has been recorded between 2400 and 300 Å on the SA61 beam line of SUPERACO in Orsay. A new electronic transition has been observed and vibrationally analysed. Nine Rydberg states have been observed and classified into Rydberg series giving two ionization limits at 12.849eV for the X 1Σ+ ionic state and at 13.117eV for the A 1II state of BO+. Two ionization limits have been observed at 754 and 374 Å. The first of these corresponds to the B 1Σ+ state and the last one to the C 1Σ+ state of BO+. The new results are compared with the ab initio calculations of Karna and Grein concerning BO and BO+. The agreement is satisfactory.

Experimental determination of the radiative lifetime of the 0, 1, 2, 3 vibrational levels of the B2Σ+ state in CO+

Abstract By observing the decay of intensity of vibrational bands of the B2Σ+ - X2Σ+ and B2Σ+ - A2Πi systems, the lifetimes of the 0, 1, 2, 3 vibrational levels of the B2Σ+ state of CO+ has been measured. The values are respectively τ=(56.8±1.3), (61.6±0.9), (66.9±2.2) and (70.5±2.9) ns. The variation of the function Re(r) cannot be obtained from the lifetime values of the B2Σ+ state.

Radiative Lifetimes of Electronic States in Diatomic Species : A Compilation of Experimental Values and a Discussion of “Limits of Error”

Abstract This is a compilation (up to the end of December 1981) of the lifetime of electronic states in diatomic species experimentally determined mainly by the phase-shift and exponential decay techniques. The meaning of “limits of error” in such measurements is discussed.

Time Resolved Spectroscopy of a Pulsed Discharge Through Water Vapor: Observation of Emissions from the C2σ+ State of OH

Abstract the (0–9) C2σ+ - A2σ+ band of OH and a complex emission located around 1850 A are both observed as a function of time in a pulsed discharge through water vapor. The results are discussed in the light of Felenboks interpretation of the origin of the 1850 A emission.

THE VUV ABSORPTION-SPECTRUM OF THE SIF FREE-RADICAL

Abstract The absorption spectrum of SiF has been observed down to the LiF absorption limit. Rydberg series nsσ npσ , and npπ have been observed up to n = 15, as well as two superexcited states.

Rydberg states of PN

Abstract The absorption spectrum of PN has been observed after the pyrolysis of P 3 N 5 by using the synchrotron radiation of SUPERACO in Orsay (France). Sixteen new states have been observed up to 1050 A and classified into five Rydberg series ( nsσ , npπ , npσ , ndπ , ndσ ) converging to 11.83 ± 0.02 eV, in perfect agreement with the photoelectron value.