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1.
Argon crystals were doped with 0.2 ppm of 41K through the nuclear reaction 40Ar (n, β-) 41K. The absorption spectrum from 300 nm to 800 nm was measured as a function of the annealing temperature. Absorption ← 42s transition of the free atom could be bands corresponding to the 42p, ← 42s and 52p, ← 42s transition of the free atom could be observed. The absorption bands depend strongly on the annealing temperature. An increase in the annealing temperature results in a blue shift of the absorption bands. 相似文献
2.
M. Paul A. Marinov J. Burde Ch. Drory J. Lichtenstadt S. Mordechai E. Navon 《Nuclear Physics A》1977,289(1):94-108
The 44Ca(d, α)42K reaction was studied at a bombarding energy of 11 MeV using a broadrange magnetic spectrograph and solid-state detectors. About thirty energy levels were identified in 42K, up to an excitation energy of 3.5 MeV. Excitation functions corresponding to some of the low-lying energy states of 42K were measured in the incident energy range from 10.4 to 11.6 MeV. Angular distributions of the α-particle groups corresponding to the excitation of about twenty energy levels in 42K have been measured. DWBA calculations were performed and L-values for most of the above transitions were deduced. The results were compared with previous information and possible spin and configuration assignments are proposed for some of the states. Centroids of states interpreted as belonging to the (1d?1)p (1f3)n, (2s?1)p (1f3)n and the (1d?1)P (1d?1 1f4)n configurations were found to be in good agreement with calculations based on the weak-coupling model. 相似文献
3.
H. Roos 《Physica A》1980,100(1):183-195
Given the C1-algebra of observables, the KMS condition is formulated in terms of the time evolution α1t of a set 0 ? () of “physical” states subject to certain natural conditions. α1t need not be defined by an automorphism group of . It is shown that, for a KMS state ω, α1t induces a 1-automorphism αωt of the von Neumann algebra πω()″ generated by the representation πω belonging to ω. 相似文献
4.
A cw dye laser beam, tuned near the Cs 8761 Å resonance (Cs1(6P) → Cs1(6D) transition) is focused into a Cs vapor. At a Cs density higher than 5 × 1015 cm-3, we observe a greater 6P population when the laser is on resonance than when it is off resonance. However, at a lower Cs density, the reverse is observed. This phenomenon is explained as due to the preferential excitation transfer process: Cs1(6D) + Cs(6S) → Cs1(6P) + Cs1(6P), and the corresponding cross secti on is estimated to be (1.5+1.5-0.7) × 10-14 cm2 by fitting the experimental results to an approximate rate-equation analysis. 相似文献
5.
Rate coefficients for the quenching of HgBr(B2∑+) by HgBr2, H2, CO2, CO, O2, N2, Xe, and Br2 are reported. HgBr(B2∑+) is formed by the photolysis of HgBr2 with the output from an ArF laser. The rate coefficients are determined by monitoring the time resolved B2∑+ → X2∑+ emission as quenching species are added. Radiative lifetimes at particular emission frequencies are also reported, and quenching mechanisms are discussed. 相似文献
6.
Low-lying intrinsic states and their associated rotational bands have been identified in 177Os and 179Os. They are the mixed i neutron states and the ?[521] states in 177Os and 179Os, as well as the ?[512] state in 177Os and the ?[514] state in 179Os. The ? sta is assumed to be the ground state, the other intrinsic states giving rise to isomers. The in-band decay properties of the ?[514] band, and the i bands show the effect of mixing. In the rotational bands in 177Os a low frequency backbending anomaly is observed but no anomaly is observed in the i. band. In 179Os the i band does backbend but at a higher frequency than in the yrast bands of the even neighbours. The systematics of the backbending frequencies, and the effects of blocking, are discussed. The rotation aligned angular momentum is deduced, and a comparison made between the i bands and the s-bands in the even neighbours. The results broadly support the identification of the s-bands with the aligned (i)2 configuration. 相似文献
7.
S. Galés E. Hourani S. Fortier H. Laurent J.M. Maison J.P. Schapira 《Nuclear Physics A》1977,288(2):201-220
The 96Zr(τ, α)95Zr reaction at 39 MeV incident energy was used to populate both the low-lying and highly excited (up to an excitation energy of 18 MeV) analog states in 95Zr and some low-lying levels in other Zr isotopes. The main components of the 2d. and 1g. hole strengths and the analogs of the 2p., 2p. and 1f. proton hole states in 95Y have been observed in this work. Angular distributions of transitions to 27 levels in 95Zr have been extracted and analysed with DWBA calculations to yield spectroscopic factors. Between the excitation energies of 1 and 3 MeV in 95Zr a number of levels with l = 2, 4 and 5 angular distributions have been identified. These are associated with the 2d, 1g and 1h components already observed in the previous study of the 94Zr(d, p) and (α, τ) reactions. The total strength and center of gravity for levels assigned to the (1g)?1 configurations in 95Zr are presented and compared to the results obtained from the studies of neutron pick-up reaction on 91Zr and 98Mo. For the isobaric analog states observed between the excitation energies of 15 and 17 MeV, total widths, Coulomb displacement energies and spectroscopic factors are also determined from this experiment and the results compared with the properties of the low-lying proton hole states in the 95Y parent nucleus. 相似文献
8.
The resonant loss in LiNdP4O12 (LNP) lasers has been investigated. The effective resonant loss coefficient for the 1.047(7) μm laser emission was measured to be 0.042 cm-1. This value can be explained by resonant absorption due to the 4I1→4F transition including the reabsorption effect of the fluorescence resulting from the 4I→4F transition. 相似文献
9.
Edgardo Gerck 《Optics Communications》1982,41(2):102-105
The magnetic dipole transition I(52P-52P) at 1.3152 μm is shown to be enhanced by collisions of the metastable iodine atoms with the parent RI molecules CF3I, C2F5I, i-C3F7I and n-C3F7I. The enhancing mechanism is exciplex emission of the RI·I(52P) molecule at 1.3 μm, with different rates for each iodide. The influence of this effect on the measurement of the quantum yields to I(52P) and of the respective reaction rates by infrared fluorescence is discussed. 相似文献
10.
A magnetic hyperfine filter for the resonance line 2P → 2S of thallium is described. This line is a hyperfine triplet and this filter transmits only the 0→1 component connecting the lower sublevel of the 2P ground state. This filter may thus be used for obtaining a population inversion in the ground state of Tl. 相似文献
11.
Using the proper connected diagram expansion which incorporates the quasi-particle effect naturally we calculated the cyclotron resonance width γ in the extreme quantum limit.(a) γ ∝ns B for a short range interaction, and (b) γ = πze2 κ-1 <?crossed h.c.h;-1 ns for Coulomb interaction, are obtained. The field (B) and concentration (ns)-dependence is in satisfactory agreement with experimental data. The variation γ = (γ21 + γ22 + …) of Matthiessen's rule γ = γ1 + γ2 + …, holds when there exist scattering centers of different kinds in the system. 相似文献
12.
The width of ψ(4.414) is surprisingly small for a c state far above the charm threshold, Γexp ≈ 33 MeV. This fact can be qualitatively understood if one makes the conservative assignment 4 3S1. The nodes of the wave function reflect as zero's of the decay amplitude in the momentum of the decay products, and are responsible for the suppression of the couplings to the ground state charmed mesons, Γ(ψ(4.414)→D+ D1 + D1 + D11 + F + F1 + F1 + F11) ≈ 15 MeV. All the modes are suppressed by factors of the order of 103 with respect to the k3 spin counting prediction. The dominant modes are predicted to be D11, F1 + F1 and D. Moreover, we show that the contributions from P-wave charmed mesons are reasonably expected to be suppressed either by phase space or by the nodes if their masses lie within certain range. We emphasize however that the smallness of the photon coupling remains to be understood. 相似文献
13.
We excited the 2T1-levels in ruby by tunable laser light, pumped bya pulsed YAG:Nd3+ laser, and observed the low temperature emissions from the 2 and sublevels of 2E in the mild bottlenecking regime. The R2-line decay time was about five-fold longer and the ratio of intensities R2/R1 higher (by up to a factor 10) than after pumping into 4T2. It is suggested that when 4T2 is pumped the relaxation is nonadiabatic, so that transitions between the sublevels occur while the 2E state relaxes to its normal (trigonal) configuration. The time-development of the relaxing state is studied. It is shown that its coherence between the 2 and sublevels leads to a narrowing of the spectral width in transition between the sublevels. 相似文献
14.
The decay of the 4G state of Nd3+ in LaCl3 and La(Cl99.6 Br0.4)3 was measured after pulsed laser excitation as a function of temperature. The decay rate is shown to depend besides the radiative transition on single-phonon relaxation between the states 4G () and 4G () and on multiphonon orbit-lattice relaxation from 4G to 2G. Partial substitution of Cl by Br only alters the radiative lifetime. 相似文献
15.
D. Soldo V. Henč-Bartolić A. Peršin 《Journal of Quantitative Spectroscopy & Radiative Transfer》1979,21(1):85-87
The atomic-state densities of the 6s[1 ]0 metastable Xe energy level and of the 5s4P, 5s4P and 5s4PBr energy levels in an Xe-Br2 mixture have been determined as a function of current strength. 相似文献
16.
The reaction 40Ca(13C, 12C)41Ca leading to the ground and low-lying ? levels has been studied at bombarding energies of 18.5 and 19.0 MeV, close to the Coulomb barrier. The cross sections have been analysed using the DWBA with previously measured calibrations to obtain the rms radii of 1f and 2p orbits in the 41Ca levels. The rms radius of the 1f point neutron orbit in the ground state relative to the 40Ca core was determined to be 3.89 ± 0.12 fm. This is compared with various theoretical predictions based on Hartree-Fock theory. The 1f orbit radius gives the point neutron excess size to a good approximation for comparison with the value of 3.45 fm deduced from Coulomb energy differences. The consistency of the results with 40Ca(t, d)41Ca experiments using a (t/d), zero-range normalization of 3.26 × 104 MeV2 · fm3 is demonstrated, and trends in neutron size parameters through the Ca isotopes are discussed. 相似文献
17.
We measure the lifetime of the 5 2D metastable level of Ba+ ions confined in a cylindrical radiofrequency trap as well as some parameters which characterize the confining properties of the trap. This is accomplished by studying the ion response to a short pulsed optical excitation saturating the 6 2S–6 2P transition.The measured lifetime of the 5 2D metastable level is 47 ± 16 s. The storage voltages for which the ion number shows a maximum are experimentally investigated. Their change when a light buffer gas is added is observed. The effect of this gas on the storage time is also specified. 相似文献
18.
Energy levels in the N = 83 nucleus 149Dy were studied by the reaction 152Gd(α, 7n) at 106 MeV bombarding energy using in-beam γ-ray spectroscopy methods. The measurements identified three isomers in this nucleus, at 1073 keV (13 ± 3 ns), at 2700±150keV (5 μs < T < 0.5 s), and above 3.5 MeV (50 ± 15 ns). The low-lying isomer is interpreted as i. The configuration ?(πh2)10+ ×vf is suggested for the state at 2.7 MeV. 相似文献
19.
Using the technique of Doppler-free two-photon spectroscopy the energies of the n2S (12 ? n ? 35) and n2D, (11 ? n ? 48) states of CsI have been measured with a thermionic detector. The absorption spectrum of molecular iodine was used as a reference giving us a total estimated accuracy of about 2 × 10-7. Taking also into account the energies of the 7–11 2S and 5 and 6 2D, states measured by other authors and using an extended Ritz-formula we found the ionization limit to be Ei = 31406.468 ± 0.006 cm-1. 相似文献
20.
M.G. White S.H. Southworth P. Kobrin D.A. Shirley 《Journal of Electron Spectroscopy and Related Phenomena》1980,19(1):115-122
Photoelectron angular distributions for the 2Π, (pπ)?1 and 2Σ+(pσ)?1 ionic states of HBr and HI have been measured at a photon energy of 21.2 eV. The asymmetry parameters for the highly localized pπ orbitals closely follow those of the “lone-pair” orbitals of the related CH3X molecules and the outer np atomic orbitals of the corresponding united atoms. Furthermore, the asymmetry parameters for the 2Π and 2Π states were found to be equal within experimental uncertainty, despite the large spin—orbit splittings of these heavy molecules. The asymmetry parameters for the 2Σ+(pσ)?1 ionic states are significantly smaller than for the 2Π(pπ)?1 states, in contrast to recent predictions based on angular momentum transfer theory. 相似文献