Analysis of influence of buffer gas admixtures on laser generation conditions in noble gas ion lasers

Time-Resolved Investigation of the Molecular Chemiluminescence SrI(A2∏1/2,3,2,B2∑+→X2∑+) and the Atomic Resonance Fluorescence Sr(53P1→51S0) Following The Pulsed Dye Laser Generation Of Sr(53PJ) in the Presence of CF3I

Laser Chemistry ◽

10.1155/1995/98207 ◽

1995 ◽

Vol 16 (2) ◽

pp. 121-138 ◽

Cited By ~ 5

Author(s):

S. Antrobus ◽

D. Husain ◽

Jie Lei ◽

F. Castaño ◽

M. N. Sanchez Rayo

Keyword(s):

Ground State ◽

Branching Ratio ◽

Atomic Emission ◽

Electronic Energy ◽

Dye Laser ◽

Pulsed Dye Laser ◽

Laser Generation ◽

Buffer Gas ◽

Resonance Fluorescence ◽

Time Resolved

A time-resolved investigation is presented of the electronic energy distribution in SrI following the collision of the optically metastable strontium atom, Sr [5s5p(3PJ)], with the molecule CF3I. Sr[5s5p(3PJ)], 1.807 eV above its 5s2(1S0) electronic ground state, was generated by pulsed dye-laser excitation of ground state strontium vapour to the Sr(53P1) state at , λ =689.3 nm {Sr(53P1←51S0)} at elevated temperature (840 K) in the presence of excess helium buffer gas in which rapid Boltzmann equilibration within the 53PJ spin-orbit manifold takes place. Time resolved atomic emission from Sr(53P1→51S0) at the resonance transition and the molecular chemiluminescence from SrI(A2∏1,2,3/2,B2∑+→X2∑+) resulting from reaction of the excited atom with CF3I were recorded and shown to be exponential in character. SrI in the A2∏1/2,3/2 (172.5, 175.4 kJ mol-1) and B2∑+ (177.3 kJ mol-1) states are energetically accessible on collision by direct-I-atomic abstraction between Sr(3P) and CF3I. The first-order decay coefficients for the atomic and molecular emissions are found to be equal under identical conditions and hence SrI(A2∏1/2,3/2, B2∑+) are shown to arise from direct I- atom abstraction reactions. The molecular systems recorded were SrI (A2∏1/2→X2∑+, Δv=0, λ=694 nm), SrI(A2∏3/2→X2∑+, Δv=0, λ=677 nm) and SrI(B2∑+→X2∑+) (Δv=0, λ=674 nm), dominated by the Δv=0 sequences on account of Franck-Condon considerations. The combination of integrated m61ecular and atomic intensity measurements yields estimates of the branching ratios into the specific electronic states, A1/2, A3/2 and B, arising from Sr(53PJ)+CF3I which are found to be as follows: A1/2,1.2 × 10-2; A3/2, 6.7 × 10-3; B, 5.1 × 10-3 yielding ∑SrI(A1/2+A3/2+B)=2.4 × 10-2. As only the X, A and B states SrI are accessible on reaction, assuming that the removal of Sr(53PJ) occurs totally by chemical removal, this yields an upper limit for the branching ratio into the ground state of ca. 98%. The present results are compared with previous time-resolved measurements on excited states of strontium halides that we have reported on various halogenated species resulting from reactions of Sr(53PJ), together with analogous chemiluminescence studies on Sr(3PJ) and Ca(43PJ) from molecular beam measurements.

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Disorientation of Cs(62P1/2) atoms, induced in collisions with noble gases

Canadian Journal of Physics ◽

10.1139/p76-085 ◽

1976 ◽

Vol 54 (7) ◽

pp. 748-752 ◽

Cited By ~ 4

Author(s):

B. Niewitecka ◽

L. Krause

Keyword(s):

Cross Sections ◽

Noble Gas ◽

Zero Magnetic Field ◽

Zero Field ◽

Buffer Gas ◽

Resonance Fluorescence ◽

Circularly Polarized ◽

Low Field ◽

Good Agreement ◽

Gas Pressures

The disorientation of 62P1/2 cesium atoms, induced in collisions with noble gas atoms in their ground states, was systematically investigated by monitoring the depolarization of cesium resonance fluorescence in relation to noble gas pressures. The Cs atoms, contained together with a buffer gas in a fluorescence cell and located in zero magnetic field, were excited and oriented by irradiation with circularly polarized 8943 Å resonance radiation, and the resonance fluorescence, emitted in an approximately backward direction, was analyzed with respect to circular polarization. The experiments yielded the following disorientation cross sections which have been corrected for the effects of nuclear spin: Cs–He: 4.9 ± 0.7 Å2; Cs–Ne: 2.1 ± 0.3 Å2; Cs–Ar: 5.6 ± 0.8 Å2; Cs–Kr: 5.8 ± 0.9 Å2; Cs–Xe: 6.3 ± 0.9 Å2. The results are in good agreement with most of the available zero-field and low-field data.

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On the excitation mechanism of hollow cathode CW noble gas mixture ion lasers

Acta Physica Academiae Scientiarum Hungaricae ◽

10.1007/bf03159428 ◽

1979 ◽

Vol 46 (3) ◽

pp. 167-175 ◽

Cited By ~ 4

Author(s):

M. Jánossy ◽

P. Tuovinen

Keyword(s):

Hollow Cathode ◽

Noble Gas ◽

Gas Mixture ◽

Excitation Mechanism ◽

Ion Lasers

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Experimental Study on the Effect of Different Noble Gas Admixtures on the Gas Temperature of Oxygen Plasma

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-2005-0104 ◽

2005 ◽

Vol 8 (1) ◽

Cited By ~ 3

Author(s):

K. Naoi ◽

T. Sakamoto ◽

H. Matsuura ◽

H. Akatsuka

Keyword(s):

Oxygen Plasma ◽

Rotational Temperature ◽

Noble Gas ◽

Optical Emission ◽

Radiative Transition ◽

Band Spectrum ◽

Gas Temperature ◽

Inner Diameter ◽

Discharge Pressure ◽

Gas Admixtures

AbstractWe measured rotational temperature of oxygen plasma by optical emission spectroscopy (OES) in order to examine approximate value of its gas temperature. We generated microwave discharge oxygen plasma in a cylindrical quartz tube whose inner diameter 26 mm with its discharge pressure 0.5 - 2.0 Torr. We measured the band spectrum of radiative transition A

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