Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Radiative lifetimes and alignment depolarization cross sections for YbI and II by the Hanle effect in a flowing helium system

Frederick H. K. Rambow, L. D. Schearer

Published Aug 1, 1976• 34 citations
Publisher

Abstract

The radiative lifetimes of the 17992-,25068-,28857-, 37414-, 40564-, and 44017-${\mathrm{cm}}^{\ensuremath{-}1}$ neutral levels and the 30392-${\mathrm{cm}}^{\ensuremath{-}1}$ ion level of Yb have been measured by the Hanle method in a fast-flowing He system. The lifetimes (in units of ${10}^{\ensuremath{-}9}$ sec) were found to be 820(20), 5.12(0.12), 14.4(0.4), 77.4(6.0), 9.32(0.6), 39.1(3.5), and 5.8(0.6), respectively. In a flowing system with He as a buffer gas the alignment depolarization cross sections with Yb were obtained and are reported here for the first time. They are (in units of ${10}^{\ensuremath{-}15}$ ${\mathrm{cm}}^{2}$) 5.0(1.0), 5.9(1.0), 5.9(1.2), 17.9(2.0), 28.2(3.0), 5.16(4.0), and 7.2(2.5), respectively.

DOI
10.1103/physreva.14.738

Related papers

6pP2 levels of ionized barium: Lifetimes and depolarization cross sections

F. M. Kelly, M. S. Mathur

The Hanle effect and its variation with density has been used to determine the depolarization cross section for collisions between the $^{2}P_{\frac{3}{2}}$ barium ions and neutral atoms. An extrapolation of the data to zero density gives a value of the average lifetime $\ensuremath{\tau}=6.22$ ns for the $6p^{2}P_{\frac{3}{2}}$ level. A further experiment gives $\ensuremath{\tau}=7.55$ ns for the $6p^{2}P_{\frac{1}{2}}$ level.

Physical Review A•Nov 1, 1978•7 citations

Radiative Lifetime of the First P322 State of Ionized Calcium and Magnesium by the Hanle Effect

W. W. Smith, Alan C. Gallagher

The lifetime of the ${\mathrm{Ca}}^{+}$ $4^{2}P_{\frac{3}{2}}$ state and that of the ${\mathrm{Mg}}^{+}$ $3^{2}P_{\frac{3}{2}}$ state have been measured by the Hanle-effect method with optical excitation from the ground states of the ions. The lifetimes are, respectively, (6.72\ifmmode\pm\else\textpm\fi{}0.20)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}9}$ and (3.67\ifmmode\pm\else\textpm\fi{}0.18)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}9}$ sec. The ions were produced by introducing traces of calcium or magnesium into an argon discharge. "Alignment" depolarization cross sections $\ensuremath{\sigma}$ were obtained for the collisional depolarization of the following states of calcium and magnesium due to collisions with argon: $\ensuremath{\sigma}(\mathrm{Ca} 4^{1}P_{1} \mathrm{state})=(1.9\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}14}{\mathrm{cm}}^{2};$ $\ensuremath{\sigma}({\mathrm{Ca}}^{+} 4^{2}P_{\frac{3}{2}} \mathrm{state})=(1.4\ifmmode\pm\else\textpm\fi{}0.2)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}14}{\mathrm{cm}}^{2};$ $\ensuremath{\sigma}(\mathrm{Mg} 3^{1}P_{1} \mathrm{state})=(1.9\ifmmode\pm\else\textpm\fi{}0.3){10}^{\ensuremath{-}14}{\mathrm{cm}}^{2};$ $\ensuremath{\sigma}({\mathrm{Mg}}^{+} 3^{2}P_{\frac{3}{2}} \mathrm{state})=(1.3\ifmmode\pm\else\textpm\fi{}0.25)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}14}{\mathrm{cm}}^{2}.$The magnitudes of these cross sections are in accord with the theories of Byron and Foley and of Omont; we give a discussion of the extension of these theories to include ion-atom collisions.

Physical Review•May 6, 1966•136 citations

Lifetimes and Cross-Sections of Laser Levels of Xenon Measured by Hanle Effect

Takanori Suzuki, Kōichi Shimoda

Hanle effect studies using circularly polarized laser beam and linearly polarized laser beam were carried out. Lifetimes, orientation and alignment destruction cross sections were measured for the 5 d 33 , 6 p 22 and 6 p 01 excited levels of xenon. The observed ratio of orientational cross section to alignment cross section for Xe–Xe scattering was 1.1±0.4 for the 5 d 33 level, and 0.55±0.2 for the 6 p 22 level. The ratio for Xe–He scattering was 0.8±0.2 for the 5 d 33 level and 0.6±0.2 for the 6 p 22 level. They are compared with those calculated by Wang and Tomlinson. The observed radiative lifetime was 520±30 ns for the 5 d 33 level, 35±2 ns for the 6 p 22 level and 37±4 ns for the 6 p 01 level. The decay rate of the 5 d 33 level observed in the coherence transfer with spontaneous emission is consistent with the width of the Mania signal.

Journal of the Physical Society of Japan•Jul 15, 1977•11 citations

Messung der Relaxation der Ausrichtung elektronenstoßangeregter Heliumzustände unter dem Einfluß von Eigenstößen und Kaskaden / Influence of Collisions and Cascades on the Measurement of Alignment Relaxation of Helium States Excited by Electron Impact

W. Schöck

Abstract Influence Using impact excitation, the measurement of alignment relaxation rates of atomic states is influenced by cascading transitions. The two methods for measuring the collisional depolarization, the Hanle-effect and the direct measurement of the polarization of the emitted radiation, were investigated theoretically and compared. The results were checked by measuring the depolarization of helium states excited by electron impact. The depolarization cross sections of the 3,4,5 3P-states were determined from Hanle-effect measurements as 1.8(4), 3.9(5), and 5.6(6) · 10-14 cm2 respectively.

Zeitschrift für Naturforschung A•Dec 1, 1972•3 citations

Oscillator Strengths of Ca II, Sr II, and Ba II

Alan C. Gallagher

The lifetimes of the $5p^{2}P_{\frac{3}{2}}$ and $5p^{2}P_{\frac{1}{2}}$ states of ${\mathrm{Sr}}^{+}$ and the $6p^{2}P_{\frac{3}{2}}$ and $6p^{2}P_{\frac{1}{2}}$ states of ${\mathrm{Ba}}^{+}$ have been measured by the Hanle-effect technique with optical excitation from the ion ground state. (The lifetimes of the ${\mathrm{Mg}}^{+}$ $3p^{2}P_{\frac{3}{2}}$ and ${\mathrm{Ca}}^{+}$ $4p^{2}P_{\frac{3}{2}}$ states were obtained by the same technique and reported previously.) These ${\mathrm{Ca}}^{+}$, ${\mathrm{Sr}}^{+}$, and ${\mathrm{Ba}}^{+}$ states each decay to a $^{2}D_{\frac{3}{2},\frac{5}{2}}$ doublet as well as to the ground $^{2}S_{\frac{1}{2}}$ state, and the branching ratios for these transitions have been measured. The ions were produced by introducing traces of the atomic vapor into an argon discharge. Consequently, the cross sections for collisional depolarization of these $^{2}P_{J}$ states due to collisions with argon were also obtained from the measurements. The experimental results are given in Tables I and II. A discussion of the ion-atom collisional depolarization cross sections is included.

Physical Review•May 5, 1967•217 citations

The density dependence of the Hanle effect in the resonance line of atomic magnesium

F. M. Kelly, M. S. Mathur

The Hanle width and hence the lifetime of the first excited 1P1 level of neutral magnesium have been measured over a wide range of densities. The natural lifetime of the 3s3p1P1 level is 2.00 ns. The depolarization cross section for collisions with the ground level neutral atom has been measured and [Formula: see text].

Canadian Journal of Physics•Nov 1, 1978•13 citations
The radiative lifetimes of the 17992-,25068-,28857-, 37414-, 40564-, and 44017-cm\ensuremath−1{\mathrm{cm}}^{\ensuremath{-}1}cm\ensuremath−1 neutral levels and the 30392-cm\ensuremath−1{\mathrm{cm}}^{\ensuremath{-}1}cm\ensuremath−1 ion level of Yb have been measured by the Hanle method in a fast-flowing He system. The lifetimes (in units of 10\ensuremath−9{10}^{\ensuremath{-}9}10\ensuremath−9 sec) were found to be 820(20), 5.12(0.12), 14.4(0.4), 77.4(6.0), 9.32(0.6), 39.1(3.5), and 5.8(0.6), respectively. In a flowing system with He as a buffer gas the alignment depolarization cross sections with Yb were obtained and are reported here for the first time. They are (in units of 10\ensuremath−15{10}^{\ensuremath{-}15}10\ensuremath−15 cm2{\mathrm{cm}}^{2}cm2) 5.0(1.0), 5.9(1.0), 5.9(1.2), 17.9(2.0), 28.2(3.0), 5.16(4.0), and 7.2(2.5), respectively.
The Hanle effect and its variation with density has been used to determine the depolarization cross section for collisions between the 2P32^{2}P_{\frac{3}{2}}2P23​​ barium ions and neutral atoms. An extrapolation of the data to zero density gives a value of the average lifetime $\ensuremath{\tau}=6.22$ ns for the 6p2P326p^{2}P_{\frac{3}{2}}6p2P23​​ level. A further experiment gives $\ensuremath{\tau}=7.55$ ns for the 6p2P126p^{2}P_{\frac{1}{2}}6p2P21​​ level.
The lifetime of the Ca+{\mathrm{Ca}}^{+}Ca+ 42P324^{2}P_{\frac{3}{2}}42P23​​ state and that of the Mg+{\mathrm{Mg}}^{+}Mg+ 32P323^{2}P_{\frac{3}{2}}32P23​​ state have been measured by the Hanle-effect method with optical excitation from the ground states of the ions. The lifetimes are, respectively, (6.72\ifmmode\pm\else\textpm\fi{}0.20)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}9}$ and (3.67\ifmmode\pm\else\textpm\fi{}0.18)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}9}$ sec. The ions were produced by introducing traces of calcium or magnesium into an argon discharge. "Alignment" depolarization cross sections $\ensuremath{\sigma}$ were obtained for the collisional depolarization of the following states of calcium and magnesium due to collisions with argon: $\ensuremath{\sigma}(\mathrm{Ca} 4^{1}P_{1} \mathrm{state})=(1.9\ifmmode\pm\else\textpm\fi{}0.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}14}{\mathrm{cm}}^{2};$ $\ensuremath{\sigma}({\mathrm{Ca}}^{+} 4^{2}P_{\frac{3}{2}} \mathrm{state})=(1.4\ifmmode\pm\else\textpm\fi{}0.2)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}14}{\mathrm{cm}}^{2};$ $\ensuremath{\sigma}(\mathrm{Mg} 3^{1}P_{1} \mathrm{state})=(1.9\ifmmode\pm\else\textpm\fi{}0.3){10}^{\ensuremath{-}14}{\mathrm{cm}}^{2};$ $\ensuremath{\sigma}({\mathrm{Mg}}^{+} 3^{2}P_{\frac{3}{2}} \mathrm{state})=(1.3\ifmmode\pm\else\textpm\fi{}0.25)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}14}{\mathrm{cm}}^{2}.$The magnitudes of these cross sections are in accord with the theories of Byron and Foley and of Omont; we give a discussion of the extension of these theories to include ion-atom collisions.
Hanle effect studies using circularly polarized laser beam and linearly polarized laser beam were carried out. Lifetimes, orientation and alignment destruction cross sections were measured for the 5 d 33 , 6 p 22 and 6 p 01 excited levels of xenon. The observed ratio of orientational cross section to alignment cross section for Xe–Xe scattering was 1.1±0.4 for the 5 d 33 level, and 0.55±0.2 for the 6 p 22 level. The ratio for Xe–He scattering was 0.8±0.2 for the 5 d 33 level and 0.6±0.2 for the 6 p 22 level. They are compared with those calculated by Wang and Tomlinson. The observed radiative lifetime was 520±30 ns for the 5 d 33 level, 35±2 ns for the 6 p 22 level and 37±4 ns for the 6 p 01 level. The decay rate of the 5 d 33 level observed in the coherence transfer with spontaneous emission is consistent with the width of the Mania signal.
Abstract Influence Using impact excitation, the measurement of alignment relaxation rates of atomic states is influenced by cascading transitions. The two methods for measuring the collisional depolarization, the Hanle-effect and the direct measurement of the polarization of the emitted radiation, were investigated theoretically and compared. The results were checked by measuring the depolarization of helium states excited by electron impact. The depolarization cross sections of the 3,4,5 3P-states were determined from Hanle-effect measurements as 1.8(4), 3.9(5), and 5.6(6) · 10-14 cm2 respectively.
The lifetimes of the 5p2P325p^{2}P_{\frac{3}{2}}5p2P23​​ and 5p2P125p^{2}P_{\frac{1}{2}}5p2P21​​ states of Sr+{\mathrm{Sr}}^{+}Sr+ and the 6p2P326p^{2}P_{\frac{3}{2}}6p2P23​​ and 6p2P126p^{2}P_{\frac{1}{2}}6p2P21​​ states of Ba+{\mathrm{Ba}}^{+}Ba+ have been measured by the Hanle-effect technique with optical excitation from the ion ground state. (The lifetimes of the Mg+{\mathrm{Mg}}^{+}Mg+ 3p2P323p^{2}P_{\frac{3}{2}}3p2P23​​ and Ca+{\mathrm{Ca}}^{+}Ca+ 4p2P324p^{2}P_{\frac{3}{2}}4p2P23​​ states were obtained by the same technique and reported previously.) These Ca+{\mathrm{Ca}}^{+}Ca+, Sr+{\mathrm{Sr}}^{+}Sr+, and Ba+{\mathrm{Ba}}^{+}Ba+ states each decay to a 2D32,52^{2}D_{\frac{3}{2},\frac{5}{2}}2D23​,25​​ doublet as well as to the ground 2S12^{2}S_{\frac{1}{2}}2S21​​ state, and the branching ratios for these transitions have been measured. The ions were produced by introducing traces of the atomic vapor into an argon discharge. Consequently, the cross sections for collisional depolarization of these 2PJ^{2}P_{J}2PJ​ states due to collisions with argon were also obtained from the measurements. The experimental results are given in Tables I and II. A discussion of the ion-atom collisional depolarization cross sections is included.