共查询到20条相似文献,搜索用时 453 毫秒
1.
A. M. Frolov 《JETP Letters》2012,96(8):491-492
The hyperfine structure splittings are determined for the lowest bound state in the positron-helium ion e +[3He(23 S)] and e +[4He(23 S)]. In particular, it has been found that the three hyperfine structure splittings—5824.3986, 76 466.5308, and 5824.4019 MHz—can be observed for the e +[3He(23 S)] ion. In the e +[4He(23 S)] ion, only one hyperfine structure splitting 82963.0427 MHz can be observed. All these values can be measured in modern experiments. 相似文献
2.
G.D. Watkins 《Solid State Communications》1975,17(10):1205-1207
The S = 1 EPR spectrum for a tin-vacancy pair in silicon reveals easily detected isotope shifts in the fine structure splitting D for the various nuclear isotopes of tin (σD/D = + 1.0 × 10?4 per unit mass) as well as well as those for the six near neighbor silicon atoms (σD/D = ?0.67 × 10?4 per unit mass). These are attributed to the different vibrational amplitudes vs isotopic mass. 相似文献
3.
S. Hörbäck Ann -Marie Pendrill Leslie Pendrill M. Pettersson 《Zeitschrift für Physik A Hadrons and Nuclei》1984,318(3):285-290
Doppler-free two-photon laser spectroscopic measurements in the deep red spectral region have been performed on the transition 42 S 1/2→42 D J in the naturally abundant isotopes 39 and 41 of atomic potassium. The 4D level isotope shift, ?81±12 MHz was obtained by combining the current results with data from Rydberg-state spectroscopy. Many-body perturbation theoretical calculations of the specific mass shift in the measured state are also presented. With the use of Brueckner orbitals the value ?70 MHz was obtained in substantial agreement with the experimental result. 相似文献
4.
R. Bayer J. Kowalski R. Neumann S. Noehte H. Suhr K. Winkler G. zu Putlitz 《Zeitschrift für Physik A Hadrons and Nuclei》1979,292(4):329-336
The metastable 23 S 1 state and the short lived 23 P states of the helium-like6, 7Li+ ion spectra have been investigated by dye laser saturation spectroscopy in a low-energy Li+ ion-beam and fluorescence light detection. The hyperfine structure splittings of all the levels, the 23 P fine structure intervals and the isotope shift of the 23 S 1-23 P transitions have been measured. These measurements were made by application of a specially constructed tunable dye laser system capable of single-mode laser scans over more than 60 GHz. 相似文献
5.
Zi-Yuan Yang 《Journal of luminescence》2007,126(2):753-758
An extended complete diagonalization method/microscopic spin-Hamiltonian (CDM/MSH) program has been developed, which is applicable for d3 ions at sites of tetragonal symmetry type I (C4v, D2d, D4, D4h) and trigonal symmetry type I (C3v, D3, D3d). The Hamiltonian includes the spin-spin (SS) and spin-other-orbit (SOO) magnetic interactions besides the spin-orbit (SO) magnetic interaction usually taken into account. Utilizing the extended CDM/MSH program, the optical spectra, the spin-Hamiltonian (SH) parameters of the ground state 4B1, and the splitting δ(2E) of the first excited 2E state for Cr3+ (3d3) ions at C4v symmetry sites in MgO crystals have been successfully investigated. It is found that although the SO magnetic interaction is the most important one, the contributions to the SH parameters and the optical spectra from the SS and SOO magnetic interactions for Cr3+:MgO crystals are appreciable and should not be omitted, especially reaching 27.8% for the zero field splitting parameter D. 相似文献
6.
We present new data on the even-parity Rydberg states of atomic thallium using two-step three-photon laser excitation technique in conjunction with a thermionic diode ion detector. Atoms are excited from the 6p 2P1/2 ground state to the 7p 2P1/2 intermediate state via two-photon excitation and subsequently promoted to the high lying ns 2 S1/2 and nd 2D3/2 Rydberg states. The first ionization potential of thallium is determined as 49,266.66(1) cm-1 using data for the ns 2 S1/2 (25 ≤ n ≤ 54) and nd 2D3/2 (24 ≤ n ≤ 65) Rydberg series. This value is believed to be more accurate because the contribution due to the hyperfine structure splitting of the 7p 2P1/2 state (0.07185 cm-1) is much smaller as compared to that of the 6p 2P1/2 ground state (0.711 cm-1). 相似文献
7.
K. Fredriksson H. Lundberg S. Svanberg 《Zeitschrift für Physik A Hadrons and Nuclei》1977,283(3):227-230
The fine-structure splitting of the 42 D state in lithium was measured using stepwise laser excitation combined with level-crossing spectroscopy. The splitting was determined to be 456.2(0.8) MHz, a considerably higher value than the one obtained in a recent level-anticrossing measurement. The new value is in good agreement with the result of a Hartree-Fock calculation, 460.2 MHz. 相似文献
8.
The full frequency dependence of the optical delay in the Cs D1 (6 2S1/2 ? 6 2P1/2) line has been observed, including all four hyperfine split components. Pulse delays of 1.6 ns to 24.1 ns are obtained by scanning across the hyperfine splitting associated with the lower 2S1/2 state. Optical control of pulse delays in cesium vapor was demonstrated by pumping the D2 (6 2S1/2 ? 6 2P3/2) transition and observing resulting holes in the D1 delay spectrum. For a pump at four times the saturation intensity, the pulse delays are reduced by a maximum of 78% in a narrow region of 110 MHz. The frequency dependence of the delays of the probe laser in the vicinity of the spectral holes agrees with a Kramers–Kronig model prediction. 相似文献
9.
We present new calculation of the Lamb shift (2P 1/2 ? 2S 1/2), fine splitting of the 2P state and hyperfine splitting of the 2S state in muonic deuterium (µd) using the quasipotential method in quantum electrodynamics. The vacuum polarization, nuclear structure, and recoil effects are calculated with the account of contributions of orders α 3, α 4, α 5, and α 6. The obtained numerical value of the Lamb shift 202.4139 meV can be considered as a reliable estimate for the comparison with forthcoming experimental data. 相似文献
10.
J.-K. Chen 《Few-Body Systems》2008,42(1-4):115-124
The S-wave state 3 S 1 and D-wave state 3 D 1 are investigated by applying the Salpeter equation. The coupled equations of the S-wave component and the D-wave component are obtained. In nonrelativistic limit, the coupled equations are decoupled and reduced to two Schrödinger equations describing the S-wave state and the D-wave state, respectively. It is shown that the S-D coupling will be of order v 4 or of higher order. For vector mesons 1??, the contribution to the decay constant comes only from the S-wave state in the nonrelativistic limit. Even when only the simple potential, the scalar and the zero component of the vector potential are considered and the orbit-spin term and tensor term are neglected, the D-wave contribution to the decay constant should also be considered in higher order. 相似文献
11.
U. Klingbeil J. Kowalski F. Träger H. -B. Wiegemann G. zu Putlitz 《Zeitschrift für Physik A Hadrons and Nuclei》1979,290(2):143-148
The isotope shift40Ca-43Ca in the 4s 2 1 S 0-4s4p 3 P 1 intercombination line as well as the hyperfine structure splitting of the 4s4p 3 P 1 state of43Ca have been remeasured by saturation spectroscopy with a tunable stabilizedcw dye laser and an atomic beam of natural Ca as absorber. The nuclear charge radius of43Ca obtained here reconciles our result with the radius obtained from measurements in muonic Ca-atoms and in the Ca resonance line. It reconfirms the fact that the charge radius of43Ca is considerably smaller than the ones of both neighbouring even isotopes. The discrepancy of our previous measurement for this charge radius was due to a wrong assignment of so far unobserved absorption lines of probably molecular origin occuring in the neighbourhood of the atomic resonances under study. 相似文献
12.
Laser-induced photodissociation of NaCs molecule has been observed when a mixture of Na and Cs metal vapour in a glass cell was irradiated by most of the lines of an argon ion laser. The photodissociation results in the 3P state of Na atoms which is correlated with theF 1Σ+ and G1π molecular states of NaCs. Distribution of photofragments over fine structure components 32 P 3/2 and 32 P 1/2 of Na has been studied. The ratio of intensity ofD 2 line (5890 Å) toD 1 line (5896 Å) of Na varies from around 2 at 5145 Å to about 3.5 at 4579 Å. The relative photodissociation cross-section increases monotonically as the wave-length of laser light decreases from 5145 Å to 4579 Å. It is seen that the 4579 Å photon is about 200 times more effective than the 5145 Å photon in causing the photoreaction NaCs + (Ar+ photon) → Na*(3P) + Cs(6S). 相似文献
13.
Utaro Furukane Toshiatsu Oda 《Journal of Quantitative Spectroscopy & Radiative Transfer》1985,33(6):645-651
Lasing conditions for He have been evaluated numerically. We have used a collisional radiative model to calculate overpopulation densities Δnij, which are defined as differences between population densities per unit statistical weight of the upper and lower excited levels i and j, respectively. Laser oscillations for the level pairs 21P-31S, 21P-41S, 21P-31D, 21P-41D, 31D-41F, 31P-41S, 31P-41D, and 33P-43S are possible when the electron densities are within well defined limits at low electron temperature (Te = 0.1 eV). For level pairs of the singlet state, the inversion mechanism for He is the same as for H. Only collisional processes produce population inversion in the triplet level pair 33P-43S. 相似文献
14.
The Eu ions confined in an RF quadrupole trap, has been optically detected. Using a tunable dye laser which is pumped by a
Nd-YAG pulsed laser system, the resonance 9S4^9S_4–6p
3/2, J = 5 transition of the Eu ions have been excited and the resulting fluorescence to the metastable 9D4-6^9D_{4-6} state has been detected. In preparation to determine the ground-state hyperfine splitting of the odd isotopes we found the
optimum trapping operating point. We have also observed a number of instabilities inside the region of the stability for an
ideal trap. These non-linear resonances arise from higher-order contributions to the ideal quadrupole potential. 相似文献
15.
《Journal of Quantitative Spectroscopy & Radiative Transfer》1986,36(6):483-490
The radiative decays and collisional quenching of Hg 61D2, 63D2, 71D2 and 73D2 atoms were investigated by time-resolved methods. Hg vapour, pure or mixed with a buffer gas in a fluorescence cell, was irradiated with u.v. light pulses from a frequency-doubled N2 laser-pumped dye laser, populating selectively each state in turn by 2-photon absorption from the 61S0 ground state. Fluorescent components arising from the decays to the 61P1 or 63S0 state were resolved with a spectrometer and their time evolutions recorded with a transient digitizer or time-to-amplitude converter and pulse-height analyzer, yielding the respective decay rates. The quenching cross sections were obtained from variations of measured decay rates with Hg or buffer-gas density. 相似文献
16.
R. -J. Champeau G. Leuchs H. Walther 《Zeitschrift für Physik A Hadrons and Nuclei》1978,288(4):323-326
The fine structure splitting of the 32 D-state of lithium was measured using the level crossing technique with delayed observation. Two nitrogen laser pumped dye lasers were used for a stepwise excitation. The linewidth observed was 40% smaller than the natural width. The result derived for the splitting is (1080.1±1.0)MHz. 相似文献
17.
Two-photon laser spectra of the Yb vapor have been obtained. Transitions to highly excited 4f14 6sns1S0 and 4f14 6snd 1D2 states are seen in direct two-photon excitation. Hybrid resonances involving 4f14 6s6p 1P01 and 4f14 5d6s 3D2 intermediate states lead to transitions to 4f14 6sns1S0, 4f14 6snp 3P02,1 and 4f14 6snd 1D2 levels. 相似文献
18.
Quantum beats between the fine structure levels of highly excitedn 2 D levels of sodium atoms have been measured by investigating the field electrons. The states were populated by stepwise excitation with two dye lasers and an electric field pulse was applied a certain time after the laser excitation. The quantum beat signal is observed when the time delay between excitation and ionization is varied. The fine structure splitting forn=21 to 31 has been measured. 相似文献
19.
M. Auzinsh K. Blushs R. Ferber F. Gahbauer A. Jarmola M. Tamanis 《Optics Communications》2006,264(2):333-341
The pure electric field level-crossing of mF Zeeman sublevels of hyperfine F levels at two-step laser excitation is described theoretically and studied experimentally for the nD3/2 states in Cs with n = 7, 9 and 10, by applying a diode laser in the first 6S1/2 → 6P3/2 step and a diode or dye laser for the second 6P3/2 → nD3/2 step. Level-crossing resonance signals are observed in the nD3/2 → 6P1/2 fluorescence. A theoretical model is presented to describe quantitatively the resonance signals by correlation analysis of the optical Bloch equations in the case when an atom simultaneously interacts with two laser fields in the presence of an external dc electric field. The simulations describe well the experimental signals. The tensor polarizabilities α2 (in ) are determined to be 7.45(20) × 104 for the 7D3/2 state and 1.183(35) × 106 for the 9D3/2 state; the electric field calibration is based on measurements of the 10D3/2 state, for which α2 is well established. The α2 value for the 7D3/2 state differs by ca. 15% from the existing experimentally measured value. 相似文献
20.
M. Van Hove G. Borghs P. De Bisschop R. E. Silverans 《Zeitschrift für Physik A Hadrons and Nuclei》1985,321(2):215-219
The hyperfine structure of the metastable 5d 2 D 3/2 state has been measured with high precision by collinear laser-rf double resonance spectroscopy on fast135,137Ba ion beams. The present data are about 100 times more accurate than those obtained by classical fast beam laser spectroscopy. 相似文献