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1.

P.W. Woods R. Chapman J.N. Mo P. Skensved J.A. Kuehner 《Physics letters. [Part B]》1982,116(5):320-324

The sub-Coulomb (t,α) reaction has been employed in the determination of the rms radii of the

3s_{12}, 2 d_{32}, 1 h_{112}

, and

2 d_{52}

proton orbits in ²⁰⁸Pb. The experimental values are compared to the results of Hartree-Fock calculations. 相似文献

2.

Shell-model studies of the 90Y, 91Zr, 92Nb and 93Mo nuclei

D.S. Chuu M.M.King Yen Y. Shan S.T. Hsieh 《Nuclear Physics A》1979,321(2):415-428

A shell-model calculation of the N = 51, 39 ≦ Z ≦ 42 nuclei is presented. The ⁸⁸Sr nucleus is assumed to be an inert closed core. The extra-core protons are restricted to the (

2 p_{12}

,

1 g_{92}

) configurations, and the active neutron is allowed to occupy the

2 d_{52}

,

3 s_{12}

,

2 d_{32}

and

1 g_{72}

orbits. The proton-proton effective interaction is directly taken from the previous analysis on the energy levels for N = 50 isotones by Ball et al. The proton-neutron effective interaction is assumed to be of the form of the surface δ-interaction. The energy spectra are calculated from a least-squares fit to the experimental data, varying the T = 0 and T = 1 strengths of the surface δ-interaction. Spectroscopic factors, E2 transition rates and two-body matrix elements are also calculated and compared with the observed values and the previous theoretical results. 相似文献

3.

Experimental and shell-model studies of the reactions ⁹¹Zr(d,p)⁹²Zr and ⁹⁰Zr(t,p)⁹²Zr

S.S. Ipson K.C. McLean W. Booth J.G.B. Haigh R.N. Glover 《Nuclear Physics A》1975,253(1):189-215

The results of high-resolution studies of the ⁹¹Zr(d, p) reaction at E_d = 12 MeV and the ⁹⁰Zr(t, p) reaction at E_t = 11.85 MeV are presented. Absolute cross sections have been measured for both reactions and (d, p) spectroscopic factors determined. A comparison of these results with earlier data has been made, and although many of the previous assignments have been confirmed, many new features concerning the structure of ⁹²Zr have been discovered. Shell-model calculations have been performed for ⁹¹Zr and ⁹²Zr using a neutron space which includes the

2 d_{52}

,

3 s_{12}

,

2 d_{32}

,

1 g_{72}

and

1 h_{112}

orbits and a proton space comprising the

1 g_{92}

and

2 p_{12}

orbits. Realistic proton-neutron and neutron-neutron interactions based on the Sussex matrix elements were used in the calculations. Spectroscopic factors have been calculated for the ⁹⁰Zr(d, p) and ⁹¹Zr(d, p) reactions and cross sections calculated for the ⁹⁰Zr(t, p) reaction. In general, good agreement between the theoretical and the experimental results has been obtained. 相似文献

4.

Radii of single-proton states in isotopes of tin

A. Warwick R. Chapman J.L. Durell J.N. Mo 《Physics letters. [Part B]》1979,87(4):335-338

Sub-Coulomb (t, α) reactions have been employed in the determination of the rms radii of the

1 g_{92}

,

2 p_{12}

and

2 p_{32}

proton orbits in ^{112,116,118,120,124}Sn. The experimental values are compared to the results of Hartree-Fock calculations. 相似文献

5.

The distribution of

3p_{12}

strength in ²⁰⁹Bi

C. Samanta I. Mukherjee P. Mukherjee 《Nuclear Physics A》1985,435(1):91-96

An optimized Woods-Saxon potential, which gives excellent fits to the observed proton states in ²⁰⁹Bi and ²⁰⁷Tl, is used to calculate the excitation energy of the unbound

3p_{12}

proton state in ²⁰⁹Bi. Using the wave functions given by the above potential, the strength of the core-particle interaction is calculated. The effect of the vibration of the core on the fragmentation of the

3p_{12}

state is estimated. It is found that the

3p_{12}

state at 5.123 MeV loses more than 80% of its strength to five

12^{?}

collective states in ²⁰⁹Bi and the observed

3p_{12}

state at 3.64 MeV is actually an almost equal mixture of the

3p_{12}

single-proton state and the (

4^{+}, 1 h_{92}

) collective state. 相似文献

6.

Quantitative evidence of weak isospin mixing in the low-lying isobaric analog resonances in ²⁰⁹Bi

R. Melzer P. Von Brentano H. Paetz Gen. Schieck 《Nuclear Physics A》1985,432(2):363-377

The excitation functions of

^{208} Pb (p, p_{0})^{208} Pb

have been measured in the energy range E_p = 14.2 to 17.4 MeV in 50 keV steps at θ_lab = 120°, 140° and 160°. The isobaric analog resonances of the parent states in ²⁰⁹Pb up to E_x = 2.5 MeV and the optical-model background were fit simultaneously at all energies and angles. The spreading widths and the values of a parameter β², which measures the isospin purity of the IAR, were determined for the

g_{92}, i_{112}, j_{152}, d_{52}

, and

s_{12}

resonances. An average value of the isospin purity of β² = 66% was found. 相似文献

7.

The structure of collective bands in ⁶⁸Ge: A microscopic view

R. Sahu S.P. Pandya 《Nuclear Physics A》1984,414(2):240-252

The collective bands of states of ⁶⁸Ge are studied using a deformed-configuration-mixing shell model based on Hartree-Fock intrinsic states. An effective interaction given by Kuo has been used. The configuration space includes the single-particle orbits

1 p_{32}, 0 f_{52}, 1 p_{12} and 0 g_{92}

. The collective positive- and negative-parity states are classified into different bands on the basis of the E2 transition probabilities amongst them. The agreement with the experiment is quite satisfactory. An attempt has been made to understand the structure of the nearly degenerate triplet of the 8⁺ states and their decay schemes. 相似文献

8.

Elastic and inelasttic scattering of polarized deuterons by ¹²⁰Sn at 28.6 MeV

G. Perrin Nguyen van Sen J. Arvieux C. Perrin R. Darves-Blanc J.L. Durand A. Fiore J.C. Gondrand F. Merchez 《Nuclear Physics A》1973,206(3):623-632

相似文献

9.

The effective T = 1 two-particle matrix elements in the fp shell

P.B. Vold D. Cline R.N. Boyd H. Clement W.P. Alford J.A. Kuehner 《Physics letters. [Part B]》1978,72(3):311-314

The ⁴¹Ca(

d

, p)⁴²Ca reaction has been used to locate the strength distributions for

p_{32}

and

p_{12}

transfer in ⁴²Ca. Effective

(f_{72})^{2}

,

f_{72} p_{32}

and

_{72}_{12}

two-body matrix elements are derived from the data and compared to theoretical predictions. 相似文献

10.

Optical absorption by neutral bound excitons

B. Stébé G. Munschy 《Solid State Communications》1982,43(11):841-846

In this note we determine the oscillator strengths for the dipole absorption of neutral bound excitons in direct gap semiconductors, using our previously obtained 35-term Page and Fraser type wave function, and taking into account the detailed electronic structure as well as the electron-hole exchange interaction.The envelope part of the oscillator strengths varies considerably with the electron-hole mass ratio

σ = m^{1}_{e} m^{1}_{h}

, and is maximum for the (D⁰, X)- complex when σ = 0.4. For typical σ-values (σ? 0.1–0.2),

?_{(D^{0},X)} ? 10?_{(A^{0},X)}

. But when σ approaches zero, the overlapping of the electron and the hole envelope wave functions of the (A⁰,X)-complex decreases progressively so that the oscillator strength also decreases and tends to zero.In the case of zinc-blende materials (T_d) and positive spin-orbit coupling at

k = 0

, we confirm that the line strength for transitions to or from

J = 12 (Γ_{6})

or

J = 52 (Γ_{7} + Γ_{8})

level of the (A⁰, X)-complex is equal to one quarter of the line strength to or from the

J = 32 (Γ_{8})

level.In the case of CdS, where our computed values are only in qualitative agreement with the experimental values, we discuss the use of the phenomenological result of Rashba. 相似文献

11.

Deformation and target spin-dependent effects in 9Be + p at 220 MeV

G. Roy H.S. Sherif E.D. Cooper L.G. Greeniaus G.A. Moss J. Soukup G.M. Stinson R. Abegg D.P. Gurd D.A. Hutcheon R. Liljestrand C.A. Miller 《Nuclear Physics A》1985,442(4):686-700

相似文献

12.

Charmed baryon pair production in e+e− annihilation

A.C.David Wright 《Physics letters. [Part B]》1977,71(2):425-428

Cross sections for charmed baryon pair production near threshold in e⁺e^? annihilation are calculated using pole-dominated form factors modified to take intoccount continuum effects. When the C₀⁺

C

₀^? production cross section is normalized with the help of data for

e^{+} e^{?} → p X

it is found that the total charmed baryon production cross

(C_{0} C_{0}, C_{1} C_{1}, C_{1} C_{1}^{1} + C_{1}^{1} C_{1}, C_{1}^{1} C_{1}^{1})

reaches a peak value of approximately 2.7 nb at √s = 5 GeV. 相似文献

13.

Multilevel description of the Rh isotopes in the interacting boson-fermion model

J. Jolie P. van Isacker K. Heyde J. Moreau G. van Landeghem M. Waroquier O. Scholten 《Nuclear Physics A》1985,438(1):15-28

We present a multilevel calculation within the framework of the interacting boson-fermion model (IBFM-1) of the odd-mass ^101–109Rh isotopes. We calculate both positive- and negative-parity states of the same hamiltonian, starting from the

1g_{92}

,

2p_{12}

,

2p_{32}

,

lf_{52}

and

2d_{52}

single-particle orbitals. We discuss energy spectra, electromagnetic E2 transition rates and one-nucleon transfer properties. We also discuss the influence of the

1f_{72}

orbital on the one-nucleon transfer properties. The results of the calculation for the negative-parity states are compared with the results of the

U(612

) supersymmetry scheme of the interacting boson model. 相似文献

14.

Heavy-quark binding and kinetic energies in heavy-light mesons and the constituent quark model

《Physics letters. [Part B]》1997,415(3):273-279

相似文献

15.

High-resolution proton scattering on ⁴⁶Ti

N.H. Prochnow H.W. Newson E.G. Bilpuch G.E. Mitchell 《Nuclear Physics A》1973,199(3):571-592

Differential cross sections were measured for ⁴⁶Ti(p, p) and ⁴⁶Ti(p, p₁) at four angles between E_p = 1.5 and 3.1 MeV, with an overall energy resolution of about 300 eV. Spins, parities, total and partial widths were extracted for 144 resonances. Six analogue states were identified. The s-wave states have expected spacing and width distributions, while the

p_{12}

states behave anomalously. The

s_{12}

,

p_{12}

and

p_{32}

strength functions were determined. 相似文献

16.

The ã3A2 ← X̃1A1 absorption spectrum of thioformaldehyde: A vibrational and rotational analysis

R.H. Judge D.C. Moule G.W. King 《Journal of Molecular Spectroscopy》1980,81(1):37-59

The results of a vibrational and rotational analysis of the banded

a ?^{3} A_{2} ← X ?^{1} A_{1}

transition in

CH_{2} S CD_{2} S

are presented. Only three of the six vibrational modes are active in the spectrum with

ν′_{2} = 13201012

,

ν′_{3} = 859798

, and

2ν′_{4} = 711516 cm^{?1}

. The spin forbidden transition gains intensity primarily by a mixing of the

^{1} A_{1} (π^{1},π)

and

^{3} A_{2} (π^{1},n)

states. This is confirmed by a rotational analysis of the 0₀⁰ band of both isotopes. The rotational analysis shows that the coupling in the

a ?^{3} A_{2}

state is near Hund's case b and that the spin constants are nearly 10 times greater than those observed for CH₂O. A

CNDO 2

calculation shows that this difference is due to the greater spin orbit coupling of S in CH₂S and to the smaller energy differences between the

B ?^{1} A_{1} (π^{1},π)

,

b ?^{3} A_{1} (π^{1},π)

,

X ?^{1} A_{1}

, and the

a ?^{3} A_{2} (π^{1},n)

states. The r₀ structure calculated from the rotational constants is

r_{CS} = 1.683 A ?

,

r_{CH} = 1.082 A ?

, β_HCH = 119.6°, and α (out of plane) = 16.0°. A simultaneous fit of the vibrational levels in ν′₄ of CH₂S and CD₂S to a double minimum potential function yielded a barrier to molecular inversion of 13 cm^?1 and an equilibrium out-of-plane angle of 15°. 相似文献

17.

Structure of positive parity states in ²⁹P and two-step processes in (p,t) reactions

K.K. Seth A. Saha H. Nann B.H. Wildenthal 《Physics letters. [Part B]》1975,59(4):333-335

From a study of (p,t) reactions on ³¹P and ³⁰Si it is suggested that in ²⁹P the states with

J^{π} = 12_{1}^{+}

and

12_{2}^{+}

, the pair

32_{2}^{+}

,

52_{1}^{+}

, and the pair

72_{3}^{+}

,

92_{1}^{+}

are related by weak coupling of a s

_{12}

proton with the states 0₁⁺, 0₂⁺, 2₁⁺ and 4₁⁺ respectively of ²⁸Si. Completely atypical L = 2 angular distributions have been obtained for the

32_{1}^{+}

and

52_{2}^{+}

states in ²⁹P and it is suggested that this is due to contribution by two-step processes. 相似文献

18.

Combination tones in the response of single degree of freedom systems with quadratic and cubic non-linearities

A.H. Nayfeh 《Journal of sound and vibration》1984,92(3):379-386

The method of multiple scales is used to analyze the response of a single-degree-of-freedom system to either the combination resonance of the additive type

Ω_{2} + Ω_{1} ≈ ω_{0}

or the combination resonance of the difference type

Ω_{2} ? Ω_{1} ≈ ω_{0}

, where

Ω_{1}

and

Ω_{2}

are the frequencies of the excitation and ω₀ is the linear undamped natural frequency of the system. To the second approximation, the combination resonance of the additive type has three effects on the steady state response. First, it produces terms having the frequencies

Ω_{1}, Ω_{2}

and

Ω_{2} + Ω_{1}

at first order and terms having the frequencies 0,

2Ω_{1}, 2Ω_{2}, Ω_{2} ? Ω_{1}

,

2(Ω_{2} + Ω_{1}), Ω_{2} + 2Ω_{1}

and

2Ω_{2} + Ω_{1}

at second order. Second, it produces a shift in the natural frequency of the system. Third, it produces a virtual primary-resonant excitation having the frequency

Ω_{2} + Ω_{1} ≈ ω_{0}

that makes the component having the frequency

Ω_{2} + Ω_{1}

be of first rather than second order. Similar effects are produced by a combination resonance of the difference type or a superharmonic resonance of order two. 相似文献

19.

Energies and orbital sizes for some Rydberg and valence states of the nitrogen molecule

Walter C. Ermler Robert S. Mulliken 《Journal of Molecular Spectroscopy》1976,61(1):100-106

Accurate SCF computations are reported on the Rydberg states of N₂ of electron configurations

---1π_{u}^{3} 2π_{u}

,

---1π_{u}^{3} 3σ_{u}

, and ---3σ_g2π_g, also on the valence states of the configuration

---1π_{u}^{3} 1π_{g}

. The Rydberg state calculations supplement those of Lefebvre-Brion and Moser. A comparison is made between the

---1π_{u}^{3} 2π_{u}

states and the parallel set of states of the

1π_{u}^{3} 1π_{g}

configuration. This comparison shows a sharp difference in the ¹Σ⁺ states of the two configurations, the ¹Σ⁺ state being very high in the latter but relatively low in the former configuration. Recknagel coefficients are given for the several states of the two configurations; as expected, these are much smaller for the

1π_{u}^{3} 2π_{u}

configuration. Also, the ¹Δ state is relatively lower for the latter configuration. 相似文献

20.

Hyperfine structure of CH₃OH

J.E.M. Heuvel A. Dymanus 《Journal of Molecular Spectroscopy》1973,45(2):282-292

Hyperfine structure of the (0, 0, 1) - (1, 0, 1) transition of methanol has been investigated by beam absorption and of the (J, 1, 3?) → (J, 1, 3+) transitions for J = 2, 3, and 6 by beam-maser spectroscopy. The best-fit results for the spin-rotation and spin-spin coupling constants

C_{JKτ±}^{(i)}

and

D_{JKτ±}^{(i)}

, respectively, are in kHz¹:

C_{101}^{(1)} = 2.4(10)

,

C_{101}^{(2)} = ?0.6(10)

,

D_{101}^{(1)} = ?13.8(9)

,

D_{101}^{(2)} = 7.0(9)

,

C_{213?}^{(1)} = ?5.0(10)

,

C_{213?}^{(2)} = ?5.5(10)

and (

C_{J13?}^{(2)} - C_{J13+}^{(2)}) = 0.98(9)

. 相似文献