raymond_1984#
T. D. Raymond, N. Böwering, C.-Y. Kuo and J. W. Keto, “Two-photon laser spectroscopy of xenon collision pairs”, Phys. Rev. A 29, 721-734 (1984)
Source record · Catalogue · Review register
Source kind: measurement
Recorded technique: Two-photon excitation of xenon 5p5 6p[1/2]0, 6p[3/2]2 and 6p[5/2]2 (1 to 10 000 Torr) by a nitrogen-laser-pumped dye laser (Coumarin 500; 0.08 A FWHM, or 500 MHz with an intracavity etalon; the UV width after doubling estimated as half the visible’s), doubled in LFM to 245-260 nm, under 100 W, 3 ns, highly linearly polarised, focused to about 15 um (1-60 MW/cm2) and refocused back on itself (counter-propagating beams); the laser power on a calibrated photodiode shot by shot. Fluorescence detected in the near infrared (6p -> 6s, NBS-traceable lamp calibration) and in the VUV at 173 nm (excimers, 1000-2800 Torr), the latter calibrated against the calculated Rayleigh scattering of xenon, d sigma / d Omega = 6 x 10^-26 cm2 (pp. 722-725).
Materials in structured entries: None recorded.
Dataset quantities: None recorded.
Contents: 0 datasets; 0 formulas.
Curation notes#
Phys. Rev. A 29(2), 721-734 (February 1984) = PDF pages 1-14 (journal page = PDF page + 720); a scan with a text layer. Identity checked against the first page (PHYSICAL REVIEW A VOLUME 29, NUMBER 2, FEBRUARY 1984; received 13 June 1983; University of Texas at Austin) on 2026-10-08. Every number below was read on the rendered pages (pp. 725-726) and Table I’s image.
NOTHING IS TAKEN AS DATA. Table I (p. 726), ‘Estimated and measured two-photon coefficients alpha as defined by Eq. (2)’, in cm4/J^2, for 6p[1/2]0, 6p[3/2]2, 6p[5/2]2: single-path estimates through 6s[3/2]1 (100, 73, 12), 5d[3/2]1 (43, 7.7, 19) and 7s[3/2]1 (92, 4.2, 17); Pindzola et al.’s Dirac-Fock length and velocity for 6p[1/2]0 (210, 58.9); experiments: Chen et al. (96, 6p[1/2]0 column), Gornik et al. (108, 12, 61), this work (43 +- 20, 4.5 +- 2, 22 +- 11; VUV detection at 1000-2800 Torr, ‘Final accuracy ... +-50%’; the infrared detection at a few Torr gave values ‘an order of magnitude smaller’). The measured ratios 6p[1/2]0 : 6p[5/2]2 : 6p[3/2]2 are given as ‘8:4:1’, +-15 % (the table’s 43 : 22 : 4.5 is 9.6 : 4.9 : 1). Why not taken: (a) the unit, cm4/J^2 (a rate per intensity squared), is not one that two_photon_excitation_cross_section (TC-872) holds; it becomes cm4 only per level, times (hbar omega)^2; (b) alpha is defined by the rate on resonance, R(0) = 6 alpha I^2 g(0) for two counter-propagating beams of intensity I (Eq. 1a), with g(0) = [pi / (2 ln 2)]^(1/2) [1 / Delta omega_1 + 1 / (Delta omega_d^2 + Delta omega_1^2)^(1/2)] for a broad laser (Eq. 1b) and 4 / gamma_e for a broad level (Eq. 1c). Eq. (1c) is 2 pi times the peak of a unit-area Lorentzian of FWHM gamma_e in angular frequency (a profile of unit area in ordinary frequency); Eq. (1b)’s Gaussian terms are 1.505 / Delta omega_1 where a unit-area profile of the two-photon spectrum (FWHM sqrt(2) Delta omega_1) has 0.664 / Delta omega_1 in angular frequency or 4.17 / Delta omega_1 in ordinary frequency; and the Doppler-free and Doppler-broadened parts are weighted equally where the 4 I1 I2 and I1^2 + I2^2 of the text would weight them 2 : 1. So frequency_variable cannot be stated for alpha, and alpha (hbar omega)^2 is not the frequency-integrated cross section in a stated convention; (c) the photon statistics of the multimode pulsed dye laser are not discussed. Table II (difference potentials C5, C6 and the quasistatic fits) and Table III (collisional branching fractions at 100 Torr): no quantity.
FINDING: kroll_1990 (TC-890). Its Table I lists this paper (Ref. 9) as sigma_tot G2(0) = 2.7, 0.28 and 1.3 x 10^-35 cm4 (‘50%’) for 2p5, 2p6, 2p9. These are alpha (hbar omega)^2 with this paper’s 43, 4.5 and 22 cm4/J^2 at 249.63, 252.48 and 256.01 nm (2.72, 0.279, 1.32 x 10^-35): right as arithmetic, but they treat g(0) of Eq. (1b) as a unit-area profile in angular frequency, which it is not as printed (above), and they enter a G2(0)-uncorrected column, which the paper neither states nor excludes. Kroll and Bischel’s Ref. 8 (Gornik) and Ref. 10 (Chen) rows are this table’s experimental rows converted the same way (108, 12, 61 -> 6.84, 0.743, 3.67; 96 -> 6.08 x 10^-35 at 249.63 nm), and its Pindzola range ‘4-13’ for 2p5 is 58.9 and 210 cm4/J^2 converted (3.73 and 13.3 x 10^-35).
FINDING: the Chen row. Table I’s caption: ‘The experimentally measured values of Chen et al. (Ref. 14) and Gornik et al. (Ref. 5) are inferred from their measured transition rates ... The laser bandwidth for the experiment by Chen was assumed to be 0.01 A.’ chen_1980 prints R ~ 2 x 10^-9 I^2 (I in W/cm2) for its Fig. 3, ‘at 252.6 nm’ (the 6p[3/2]2 resonance), with a laser of 0.4 A FWHM. The same group’s later accounts of that measurement put it at 2496 A, the 6p[1/2]0 resonance: Pindzola, Payne and Garrett (Phys. Rev. A 24, 3115 (1981), pindzola_1981b) quote ‘W = 2.4 x 10^-23 I^2’ (I in erg/cm2 s, i.e. 2.4 x 10^-9 in W/cm2) for 6p[1/2]0 and a laser width ‘between 0.05 and 0.01 A’ (their Table II uses 0.05 and 0.10 A, which reproduce its 2.73 and 5.46 x 10^-12 cm4/erg2 with G = (8 ln 2 / pi)^(1/2) / Delta_L: the text’s 0.01 is a slip for 0.10); Payne et al. (Adv. At. Mol. Phys. 17, 229 (1981), payne_1982) give K = 2 x 10^-9 s-1 W-2 cm4 at 2496 A and ‘between 0.05 and 0.1 A’. This table’s column follows them, and its 0.01 A may come from Pindzola et al.’s slip. The 96 is reproduced, within 1.5 %, as (R / I^2) / g with R / I^2 = 2 x 10^-9, a 0.01 A Gaussian laser and xenon’s two-photon Doppler width (0.086 cm-1) in a unit-area profile in angular frequency (bokor_1980’s form): 97.4 at 249.63 nm, 95.3 at 252.48 nm; so the reproduction does not decide the level. With the 0.08 A of Payne et al. the same step gives 730 cm4/J2 (alpha (hbar omega)^2 = 4.6 x 10^-34 cm4), with chen_1980’s 0.4 A about 2 x 10^-33 cm4: the row’s 96 rests on the narrowest assumed width. The Gornik row is not reproduced (gornik_1981’s notes): it corresponds to g = 9.1 x 10^-11 s at 1.8 MW/cm2 for all three levels.
CHECKED: the Dirac-Fock row. Pindzola, Payne and Garrett’s Table II prints 2.10 x 10^-12 (length) and 5.89 x 10^-13 cm4/erg2 (velocity) for 6p[1/2]0: this table’s 210 and 58.9 cm4/J2 are those numbers in J. But their alpha is defined by W = alpha I^2 G(omega) with G = (8 ln 2 / pi)^(1/2) / Delta_L at resonance (a Gaussian laser, no Doppler term), not by this paper’s Eqs. (1a, 1b): the rows of the table are in different conventions. The Rayleigh cross section is printed ‘d sigma / d Omega = 6 x 10^-26 cm^-2’ (p. 725): cm2 is meant.
TWO-PHOTON DATA CITED, NOT IN THE LIBRARY: R. T. Hawkins, H. Egger, J. Bokor and C. K. Rhodes, Appl. Phys. Lett. 36, 391 (1980); N. Böwering, C.-Y. Kuo, T. D. Raymond and J. W. Keto, in Spectral Line Shapes (de Gruyter, Berlin, 1983), Vol. 2, p. 927 (the authors’ earlier line-shape work on these levels); W. Gornik, E. Matthias and D. Schmidt, J. Phys. B 15, 3413 (1982) (with gornik_1981, the paper’s Ref. 5). The paper’s Ref. 15 (Pindzola, Payne and Garrett) is curated as pindzola_1981b.
Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.
Datasets#
No datasets are recorded.
Formulas#
No formulas are recorded.
Corrections#
No dataset errata are recorded in this source record.
Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the review register for the checks and decisions.