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Petrosky, V. E.

Publications and source records attributed to Petrosky, V. E..

Continuum ionization transition probabilities of atomic oxygen

The technique of photoelectron spectroscopy was employed in the investigation. Atomic oxygen was produced in a microwave discharge operating at a power of 40 W and at a pressure of approximately 20 mtorr. The photoelectron spectrum of the oxygen with and without the discharge is shown. The atomic states can be clearly seen. In connection with the measurement of the probability for transitions into the various ionic states, the analyzer collection efficiency was determined as a function of electron energy.

Samson, J. A. R.↗

Partially autoionizing states of atomic oxygen

Certain Rydberg states and an intershell transition of atomic oxygen were shown to partially autoionize, and to produce emission spectra competitive with autoionization. These states are forbidden to autoionize on the basis of LS coupling; but they were observed both in emission spectroscopy and in photoelectron spectroscopy. The results explain an unidentified structure in the 584 Angstrom He I atomic O spectrum observed by previous investigators.

Samson, J. A. R.↗

Continuum ionization transition probabilities of atomic oxygen

The technique of photoelectron spectroscopy was used to obtain the relative continuum transition probabilities of atomic oxygen at 584 A for transitions from 3P ground state into the 4S, D2, and P2 states of the ion. Transition probability ratios for the D2 and P2 states relative to the S4 state of the ion are 1.57 + or - 0.14 and 0.82 + or - 0.07, respectively. In addition, transitions from excited O2(a 1 Delta g) state into the O2(+)(2 Phi u and 2 Delta g) were observed. The adiabatic ionization potential of O2(+)(2 Delta g) was measured as 18.803 + or - 0.006 eV.

Samson, J. R.↗

Partially autoionizing states of atomic oxygen

The Rydberg states 3d' (3Po)2,1,0 and 3s'' (3Po)2,1,0 and the inner shell transition 2s 2p5 (3Po)2,1,0, which are forbidden to autoionize on the basis of LS coupling, were observed in emission spectroscopy and in autoionization spectra produced in the photoelectron spectrum of atomic oxygen.

Samson, J. A. R.↗