The K-shell ionization probability Pk was measured as a function of Ep across the strong resonance 56Fe(p,p)56Fe at 2.522 MeV and about 50 % variation was observed. For a large ratio of the K-shell binding energy to the total width of the nuclear resonance, Uk/Г≥5, the present experimental result is still in good agreement with theoretical calculation based on Blair and Anholt’s formula.

Thin-target yield curves have been measured for the 55Mn(p, γ)56Fe and 55Mn(p,n)55Fe reactions in the Ep = 1420−1470 keV region. The three resonances at Ep = 1441, 1446 and 1455 keV which show strong γ-ray ground-state transitions are interpreted as the fragmented analogue of the 56Mn Jπ = 1+ second excited state. With Ge detectors at θ = 90° and 55° (with Compton suppression in the latter case) γ-ray spectra with good statistics have been measured at these resonances and at Ep = 1435, 1452 and 1460 keV, which yield resonance branchings, branchings of 42 bound states (of which several were previously unobserved), accurate excitation energies (ΔEx = 0.03−0.5 keV) of 51 bound states, Jπ restrictions for many levels, and the DSA lifetimes τm = 14 ± 3 and 9 ± 4 fs for the strongly excited levels at Ex = 4867 and 5023 keV, which can be regarded as fragments of the antianalogue configuration. The 55Mn(p,γ)56Fe reaction energy has been measured as Q = 10183.84 ± 0.17 keV.

The ground-state radiative widths of the Ex = 14.393 and 16.975 MeV, T = 32 levels of 9Be were measured with a new γ-ray resonant absorption technique. Thin boron targets and broad resonances in the 11B(p, γ0γ1)12C reaction were used to produce the required monochromatic γ-rays of variable energy. The total width of the 16.98 MeV level was obtained from measurements in a separate high-resolution 7Li(d, γ)9Be experiment. The result leads to a revision of partial widths of the 16.98 MeV level that were reported earlier. The present results are compared to results of (e, e') scattering and, along with the revised particle widths of the 16.98 MeV level, to shell-model calculations. The isospin mixing and giant M1 character of the levels are also discussed.

The reaction energies of 25Mg(n, γ)26Mg and 25Mg(p, γ)26Alm have been measured as Q = 11093.24 6 and 6078.09 8 keV, respectively, which yields Q = 4232.81 10 keV for the 26Alm(β+ + EC)26Mg decay energy. By combining it with the known 26Alm half-life and by applying electromagnetic corrections one obatains Ft = 3073.5 18 s for this superallowed 0+ → 0+ decay, in good agreement with the value for the 14O “standard” 0+ → 0+ decay Ft = 3075.18 16 s, thus resolving a long-standing discrepancy.

Yield curves of the 55Mn(p,γ)56Fe and 55Mn(p,n)55Fe reactions have been measured in the Ep=1420–1470 keV region. The three components, at Ep=1440, 1446 and 1455 keV of the split analogue of the Jπ=1+ 0.11 MeV 56Mn level are completely resolved. The Compton‐suppressed Ge γ‐ray spectra taken at these three resonances with good statistics all show strong primaries to levels at Ex=4866 and 5023 keV, which can be regarded as components of the split antianalogue. Energies and γ‐ray branching ratios of many 56Fe levels have been obtained with high precision. The Q‐value of the 55Mn(p,γ)56Fe reaction amounts to 10 184.10±0.18 keV.

This work gives the experimental verification about the existence of the 11.528 MeV state in 24Mg which was newly discovered with the recoil-coincident technique in HI reaction. Resonant γ-ray absorption method has been used. Several dips have been observed in the resonance absorption transmission curve and recognized to be the fine structure around the 11.528 MeV excited energy level. The excitation energy and level width were deduced for each sub-level and the total width of energy level 13.321 MeV in emitting nucleus 28Si was also obtained from data fitting procedures.

本文介绍用γ共振吸收法测量 28 Si、 24 Mg和 40 Ca三个核素部分高激发态能级寿命的实验结果,并对γ共振吸收法作了评述。

In order to explore the Jπ=1+; T=1 states in 40Ca between 11.0 and 12.0MeV, which have been predicted recently, the measurements of the 39K(p,γ)40Ca reaction have been taken. Nine-resonances appeared in the region Ep=2.7-3.8MeV, and six of them corresponding to Ep=2749, 3085, 3135, 3202, 3417 and 3708ke were observed for the first time with the (p,γ) reaction. The spin, parity and isospin of the 11.083MeV state in 40Ca are determined to be Jπ=1+; T=1. The M1 transition strength B(M1)uparrow- of this state from the ground state is 0.24μ02. The result is qualitatively in agreement with the the oretical prediction.

The projectile energy dependence of K-shell ionization probability have been measured across the narrow resonance 2.522Mev with large ratio of Uk/Γ=5.3 in the reaction 56Fe(p, p) 56Fe. The frame work of the theory proposed by Blair and Anholt was introduced to analyze the results.

This paper presents the experimental result of K-shell ionization probability over 2.52 MeV p-wave narrow resonance in the reaction of 56Fe(P, P0)56Fe. The 50% modification of KX-ray emission probability on resonance relative to off resonance has been clearly observed. It indicates that with the ratio UK/Γ as large as 5.3, the interference between the incoming and outgoing target K-shell ionization amplitudes in an atomic collision still exists. From the comparison of calculation based on theoretical formula of Blair and Anholt with the experimental result. The imaginary part of the atomic monopole amplitude Imb0 was deduced and the R0=Imb0/Reb0 was obtained as +1.8.

In order to explore the Jπ=1+; T=1 states in 40Ca between 11.0 and 12.0MeV, which have been predicted recently, the measurements of the 39K(p,γ)40Ca reaction have been taken. Nine-resonances appeared in the region Ep=2.7-3.8MeV, and six of them corresponding to Ep=2749, 3085, 3135, 3202, 3417 and 3708ke were observed for the first time with the (p,γ) reaction. The spin, parity and isospin of the 11.083MeV state in 40Ca are determined to be Jπ=1+; T=1. The M1 transition strength B(M1)uparrow- of this state from the ground state is 0.24μ02. The result is qualitatively in agreement with the the oretical prediction.

Based on angular distributions of the proton capture reaction and Weisskopf estimates of ..gamma..-ray transition strengths, the spins of light nuclei are studied. The spin of the 13.321-MeV excited state in /sup 28/Si is deduced to be 2.

The total widths of the two excited states at 9603.9, 10 321.0 keV and of the doublet at 9864.6, 9868.8 keV in 40Ca have been measured with resonance γ-ray absorption. The gamma radiations from the 39K(p, γ) reaction at Ep = 1307.2, 2042.8 and 1595.0 keV have been selected to excite the corresponding levels in 40Ca. The obtained widths of the 9603.9 and 10 321.0 keV levels are 188 ± 47 and 91 ± 15eV, respectively. The resonance γ-ray absorption technique with cross excitation was used in the measurement for the 9864.6,9868.8 keV close-lying doublet. The analysis of experimental results was extended to this special case and the obtained level widths are 100 ± 24 and 899 ± 214 eV. In addition, the (p, γ) resonant strengths of the 9603.9 and 10321.0 keV states have also been discussed.

The level width of the 10.71-MeV state in /sup 24/Mg is measured by using the resonant absorption method. The 10.71-MeV ..gamma.. rays produced in /sup 27/Al( p,..gamma..) /sup 28/Si at E/sub p/ = 937 keV and the resonant absorption dips for different absorber thicknesses are observed. The data are fitted by a double convolution integral function and the exact energy value is deduced to be E/sub x/ = 10 712.7 +- 0.4 keV with a level width GAMMA/sub a/ equal to 19.8 +- 2.9 eV.