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1.
The excitation energies, reduced E2 transition probabilities and spectroscopic factors in the (3He, d) reaction for the levels with positive parity in 197Au up to about 1 MeV, together with the corresponding data for 196Pt, are shown to be in overall agreement with the predictions of a dynamical supersymmetry scheme recently proposed for nuclei in this mass region.  相似文献   

2.
3.
The dependence of the low-lying spectra of Λ, Σ9Be hypernuclei on hyperon-α interaction in the molecular α + α + Λ(Σ) scheme has been studied. A suggestion is made for obtaining the strengths of both p-wave and spin-orbit Λ-α interactions from the experimental Λ9Be spectrum. A relation between the Σ0-binding energies BΣ(Σ9Be) and BΣ(Σ9He) has been established and on its basis a prediction is made about a possible binding energy of Σ5He.  相似文献   

4.
Spin and parity values have been determined for sub-Coulomb resonances of the 16O + 12C system.  相似文献   

5.
The elastic electron scattering cross sections for 142,146,150Nd have been measured at momentum transfers between 0.2 and 0.8 fm?1. The results do not support the anomalously small skin thickness values obtained in a previous low-energy electron scattering experiment.  相似文献   

6.
Internal conversion electron spectra of the transitions 4.4 keV, 10.0 keV, 14.4 keV, and 324.1 keV in the decay 223Ra → 219Rn were measured. E2/M1 mixing ratios of these γ-transitions were deduced from conversion electron intensity ratios: δ2 = 3.8(4) · 10?3, 2.35(18) · 10?3, 12.85(36) · 10?3, 0.23(3). The half-lives of the 4.4 keV and 14.4 keV levels were determined as T12 = 15.4(1.3) nsec and 0.875(30) nsec. Reduced transition probabilities were calculated and compared to the Weisskopf estimates. αγ angular correlation measurements of the transitions 269.6 keV, 324.1 keV, and 338.6 keV and an αγ linear polarization measurement of the 269.6 keV transition were performed for spin determination. We assign I = 72 to the 219Rn ground state and I = 52 or 92 to the 269.6 keV state. All other low excitations including the 338.6 keV level have spins I = 52, 72, or 92. The spins of the states 158.7 keV and 14.4 keV are equal. The 223Ra ground state spin is I = 72 or 92. The possibility of an interpretation of the transitional nucleus 219Rn in the frame of the collective model is discussed.  相似文献   

7.
Neutral and charged pion-photo production on 3H and 3He nuclei have been observed in the Δ(1232) resonance region. Resonance averaged cross-sections are presented as functions of momentum transfer.  相似文献   

8.
The branching ratios are calculated for 11ΛB decay to the 11C ground and excited states below 8 MeV for two possible spin values of 11ΛB. It is found that the decay rate to the 11C state at E = 6.48 MeV is comparable in magnitude to that leading to the 11C ground state if J(11ΛB) = 52 is assumed. This result, unlike the branching ratios calculated for the J(11ΛB) = 72 case, is in accord with experiment and lends support to the assumption that J = 52 holds for 11ΛB. The necessity of the reinterpretation of some of the so-called 13ΛC events in terms of 11ΛB → π? + 11C1 is indicated.  相似文献   

9.
Starting with a set of harmonic oscillator wavefunctions, we calculate partial decay rates of excited Δ1 and N1 states into a nucleon with single pion emission. Good agreement with values estimated from data is obtained for N ≤ 6, thus indicating that the simple quark model is reasonable over a much wider range than expected. The calculated decay rates of the even higher states depend more sensitively on the finer details of the nucleon wavefunction.  相似文献   

10.
Pauli and short range correlations are studied and shown to be important in the 13C (π+, π0)13N reaction near the resonance, helping to reduce appreciably the discrepancies between the experiment and previous theoretical results.  相似文献   

11.
The thermal neutron induced (n, α) reaction cross section of 238U was measured using the highly pure thermal neutron beam from the 87 m curved neutron guide at the High Flux Reactor of the ILL (Grenoble). The energy spectrum showed an α-particle line with Eα = 9.05±0.06 MeV and σ(n, α) = 1.3±0.6 μb. The α-particle energy was used to calculate the 235Th mass of 235.04700±0.00008 amu, the Qα value of 9.20±0.06 MeV for the 238U(n, α)235Th reaction and the Qβ value of 1.44±0.08 MeV for the β-decay of 235Th. The cross-section data are compared with the results obtained with the statistical model calculation.  相似文献   

12.
The46Ti(p, n)46V reaction threshold has been measured as 8007.7 ± 1.8 keV, equivalent to an energy release of 6030.6 ± 1.8 keV in the beta decay46V+)46Ti. The 46V half-life has been measured as 422.28 + 0.23 ms. The corresponding ft value is reasonably consistent with those of other superallowed Fermi decays.  相似文献   

13.
At helium temperatures two sharp lines at 9350 and 9510 cm?1 have been observed for the first tune on the low-energy side of the broad double-peaked absorption corresponding to the 5T2g5Eg transition in Fe2+ at the octahedral site in MgO. The lower energy line has a half width of 4 cm?1; Zeeman measurements show that it is of magnetic dipole origin. The Zeeman spectra are consistent with those expected for a pure electronic transition from the (5T2g)T2g ground state to the 5Eg excited state. The second line, with a halfwidth of ~ 35 cm?1, a vibrational sideband.  相似文献   

14.
The threshold energy for the reaction 35Cl(α, n)38mK has been measured to be 6674.8±3.2 keV and the Q-value for the reaction 35Cl(α, p)38Ar to be 837.2±2.4 keV. From the measurements a value of 5021.2±3.4 keV was obtained for the end-point energy of the decay 38mK(b+)38Ar. The half-life was measured as 925.6±0.7ms and hence an “effective” ?t value was calculated, giving the result 3106±10 s with the inclusion of outer radiative corrections to order Z2α3 and 3088±10 s allowing also for calculated charge-dependent effects.  相似文献   

15.
We investigate the 40Ca(d, α0, 1, 2, 4)38K reactions for Ed = 4.00–4.61 MeV. The α1 and α4 transitions are isospin forbidden. The resonant-like structures observed in the α0, α1, α2, and α4 transitions are consistent with Ericson theory. In addition we can fit a portion of the α1, data with a few interfering Breit-Wigner resonances. The level parameters for the corresponding 42Sc levels are given.  相似文献   

16.
The analysing power of the 7Li(d, n0) 8Be reaction for vector and tensor polarization of an 800 keV deuteron beam, as well as the relative cross section for the unpolarized beam were measured at 7 to 9 angles between 0° and 160°, using a thick target. Analysis in terms of (l, s, Jπ) matrix elements shows that two intermediate states with Jπ = 32+ and Jπ = 52? present, strongly interfering with each other. Assignments to known 9Be levels and to threshold resonances as suggested by Hackenbroich and Seligman are briefly discussed. The magnitude of the vector analysing power makes the reaction interesting as a monitor for the vector polarization of low-energy deuteron beams.  相似文献   

17.
In deep inelastic interactions of 200 GeV muons with a carbon target, we have found 17 events of the type μ±N→μ±μ?μ?X (“wrong-sign” dimuons). We derive upper limits of 1.2% (90% CL) on D0-D0 transitions (mixing) or, alternatively, of 9 pb (90% CL) cross section for BB pair production as possible sources of such events.  相似文献   

18.
It was the aim of the present work to extract nuclear wave functions directly from experimental data of β-transitions. As a favourable example the 1? (1.153 MeVβ?)0+ β-transition of 210Bi(RaE) was studied. The results obtained are compared with theoretical wave functions and good quantitative agreement, especially for the ground state of the daughter nucleus 210Po, was found. It is explicitely demonstrated how, in this case, the higher order terms of the transition matrix elements contribute. The results for the matrix element ratios μ and Λ are discussed. In particular it is shown that it is not possible to test CVC theory by examining Λ.  相似文献   

19.
A red-degraded band head, normally badly overlapped by the gamma system, A3Φ - X′ 3Δ, of zirconium oxide, appears in emission spectra of zirconium arcs and in absorption spectra of S-type stars and of frozen rare gas matrices containing zirconium. The emission band has been examined at high-resolution with the aid of separated zirconium isotopes. Identification of the band as 0-0 of a 1Π - X 1Σ+ system of zirconium oxide is confirmed by rotational analysis where the following constants (cm?1) are obtained for 90Zr16O:
B0′(R,P) = 0.40142 D0′(R,P) = 3.51 × 10?7
B0′(Q) = 0.40166 D0′(Q) =3.52 × 10?7
B0″ = 0.42263 D0″ =3.19 × 10?7
ν0 = 15383.81s
The Λ-type doubling in the 1Π state and the question of whether X 1Σ+ or X′ 3Δ is the true ground state of ZrO are discussed.  相似文献   

20.
Q gravity     
R.B. Mann 《Nuclear Physics B》1984,231(3):481-492
The geometrical structure of an extended theory of gravitation incorporating the quaternion field is investigated. A lagrangian is constructed and shown to be pure real as a consequence of the geometrical structure. The structure of spacetime becomes nonabelian; however, the base manifold in which physics takes place, remains real and n-dimensional.  相似文献   

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