Nuclear orientation of negative parity states of 131Xe

The anisotropies of the 177, 326, and 503 keV γ-transitions between negative parity states of ¹³¹Xe have been remeasured in the decay of oriented ¹³¹I nuclei. In addition the linear polarization of the 503 keV radiation has been determined with a Compton polarimeter consisting of two Ge(Li) detectors. A combined analysis of the reported experiment and earlier internal conversion and angular distribution data yields the unique assignments $\text{9}\text{2}{}^{\mathrm{?}}\text{and}\text{7}\text{2}{}^{\mathrm{?}}$ for the levels at 341 and 667 keV. The $\text{E2}\text{M1}$ mixing ratios of the 177 and 326 keV transitions are δ(177) = ?4.5 ± 1.5 and δ(326) = ?4.4 ± 1.6. The intensity of the L = 2 component in the first forbidden β-decay to the 667 keV level is at most 60 %.     

High spin states in 57Co

High spin states of ⁵⁷Co have been studied via prompt γ-ray spectroscopy in the reactions ⁴⁸Ti(¹²C, p2n) and ⁵⁴Fe(α, p) at 26–48 MeV and 12–24 MeV, respectively. The energies and decay modes of these levels were determined from the analysis of γ-ray singles and γ-γ coincidence spectra, excitation functions, angular distributions and correlations. The relevant lifetimes were measured by the Doppler-shift attenuation method. The new levels established in this work are at 4037, 4814 and 5918 keV with the most probable J^π assignment of $\text{15}\text{2}{}^{\mathrm{?}}$, if $\text{17}\text{2}{}^{\mathrm{?}}$ and $\text{19}\text{2}{}^{\mathrm{?}}$, respectively. The previously known level at 2524 keV was assigned to have $\text{J}{}^{\mathrm{\pi }}\text{=}\text{13}\text{2}{}^{\mathrm{?}}$. These together with the known $\text{9}\text{2}{}^{\mathrm{?}}$(1224 keV) and $\text{11}\text{2}{}^{\mathrm{?}}$(1690 keV) levels constitute the yrast states of ⁵⁷Co. The measured lifetimes of the above six levels are (in order of increasing energies) 0.085±0.030, 0.32±0.10, 0.16±0.06, 0.10_?0.07^+0.06, 1.5_?0.5⁴ and 0.17_?0.07^+0.08 ps, respectively. Comparisons with some theoretical calculations are presented.     

Coulomb excitation of 85Rb and 87Rb

Energy levels of ⁸⁵Rb and ⁸⁷Rb have been studied via de-excitation γ-rays following Coulomb excitation with ³⁵Cl ions. In addition to the known negative-parity states at 151.2 keV and 868.2 keV in ⁸⁵Rb, two states at 281.0 keV and 731.8 keV have been found with fourγ-ray transitions of 129.8, 281.0, 450.8 and 731.8 keV. Only one Coulomb excited state at 402.6 keV in ⁸⁷Rb has been observed. The B(E2↑) values (in units e² · b²) have been determined as 0.0035±0.0004 (151.2 keV), 0.0016±0.0002 (281.0 keV), 0.0101 ±0.0010 (731.8 keV), and 0.036±0.004 (868.2 keV) for the states in ⁸⁵Rb, and as 0.0054±0.0006 (402.6 keV) for the state in ⁸⁷Rb. The mean lifetimes of the 731.8 keV and 868.2 keV states have been measured by the Doppler shift attenuation method as 6.4±0.7 psec and 4.2±0.5 psec respectively. Angular distribution measurements allow unique spin and parity assignments of $\text{1}\text{2}{}^{\mathrm{?}}$ and $\text{3}\text{2}{}^{\mathrm{?}}$ to the 281.0 keV and 731.8 keV levels respectively. The spin and parity of the 868.2 keV level has been restricted to $\text{5}\text{2}{}^{\mathrm{?}}$ or $\text{7}\text{2}{}^{\mathrm{?}}$.     

Measurement of the decay ϒ′→ϒπ+π−

We report the first observation of the decay $\text{?′→?π}{}^{\mathrm{+}}\text{π}{}^{\mathrm{?}}\text{→}\text{l}{}^{\mathrm{+}}\text{l}{}^{\mathrm{?}}\text{π}{}^{\mathrm{+}}\text{π}{}^{\mathrm{?}}$. The 7 events seen yield a branching ratio B(?′→?π⁺π^?)=(19±8)%. A consistent value of B=(26±13)% is obtained from the charged multiplicities of the ?′ and ? decays. Using these values we deduce Γ_tot(?′)=(31⁺¹⁰_?8) keV and B_ee(?′)=(1.8±0.5)%. Furthermore we estimate Γ(?′→gg?)=(10±5) keV in agreement with QCD predictions using vector gluons while one would expect 100 keV with scalar gluons.     

Electron capture decay of 245Bk (4.90 d) and 246Bk (1.80 d)

The electron capture decay schemes of ²⁴⁵Bk and ²⁴⁶Bk have been investigated by measuring the γ-ray and conversion-electron spectra of mass-separated ²⁴⁵Bk and ²⁴⁶Bk samples. The γ-ray spectra were measured with a 25 cm³ Ge(Li) spectrometer and the conversion-electron spectra were measured with a cooled Si (Li) detector. Multipolarities of most of the transitions in ²⁴⁵Cm and ²⁴⁶Cm were deduced. The half-lives of ²⁴⁵Bk and ²⁴⁶Bk were determined by following the decay of the 252.85 and 798.7 keV photopeaks and were found to be 4.90 ± 0.03 d and 1.80 ± 0.02 d, respectively. The α/(α+EC) ratio for the ²⁴⁵Bk decay was measured to be (1.2 ± 0.1) × 10^?3. On the basis of the present investigation the following non-rotational states were identified in ²⁴⁵Cm: $\text{7}\text{2}{}^{\mathrm{+}}$ [624], 0; $\text{5}\text{2}{}^{\mathrm{+}}$[622], 252.85; $\text{1}\text{2}{}^{\mathrm{+}}$ 355.95; $\text{3}\text{2}{}^{\mathrm{?}}$ vibrational, 633.65; and $\text{1}\text{2}{}^{\mathrm{+}}$[620], 740.95 keV. The $\text{3}\text{2}{}^{\mathrm{?}}$ state at 633.65 keV is int as a K_π = 2^? phonon coupled to the i$\text{7}\text{2}{}^{\mathrm{+}}$[624] single-particle state. Our measurements of ²⁴⁶Bk γ-ray and conversion-electron energies and intensities confirm previous level assignments in ²⁴⁶Cm.     

Lifetimes of low-lying states in 19F

Lifetimes of low-lying states in ¹⁹F were measured using the Doppler-shift attenuation method through the ¹⁵N(α, γ)¹⁹F reaction. Values of τ_m = 3700 ± 700 fs (1.35 MeV), 140 ± 15 (1.46), 19 ± 7 (4.00) and 63 ± 19 (4.03) were obtained for the lowest $\text{5}\text{2}{}^{\mathrm{?}}$, $\text{3}\text{2}{}^{\mathrm{?}}$, $\text{7}\text{2}{}^{\mathrm{?}}$ and $\text{9}\text{2}{}^{\mathrm{?}}$ members, respectively, of the $\text{K}{}^{\mathrm{\pi }}\text{=}\text{1}\text{2}{}^{\mathrm{?}}$ rotational band and 5 ± 3 fs (1.55 MeV) and 370 ± 25 (2.78) for the $\text{3}\text{2}{}^{\mathrm{+}}$ and $\text{9}\text{2}{}^{\mathrm{+}}$ members of the $\text{K}{}^{\mathrm{\pi }}\text{=}\text{1}\text{2}{}^{\mathrm{+}}$ ground-state band. For the Doppler-shift attenuation analysis correction factors of the nuclear and electronic stopping powers were determined by measuring the Doppler-shift attenuation and γ-ray line shape of the 2.78 → 0.20 MeV transition and range values of 100, 200. 300 and 370 keV ¹⁹F nuclei in tantalum. All calculations were done with Monte Carlo methods. The transition strengths are discussed in terms of different theoretical predictions.     

Interference effects in 12C(p, γ)13N and direct capture to unbound states

Excitation functions of the capture reaction ¹²C(p, γ₀)¹³N have been obtained at θ_γ = 0° and 90° and E_p = 150–2500 keV. The results can be explained if a direct radiative capture process, E1(s and d → p), to the ground state in ¹³N is included in the analysis in addition to the two well-known resonances in this beam energy range $\text{[E}{}_{\mathrm{p}}\text{= 457(}\text{1}\text{2}{}^{\mathrm{+}}\text{)}$ and 1699 $\text{(}\text{3}\text{2}{}^{\mathrm{?}}\text{) keV]}$. The direct capture component is enhanced through interference effects with the two resonance amplitudes. From the observed direct capture cross section, a spectroscopic factor of C²S(l = 1) = 0.49 ± 0.15 has been deduced for the $\text{1}\text{2}{}^{\mathrm{?}}$ ground state in ¹³N. Excitation functions for the reaction ${}^{12}\text{C(p,γ}{}_1\text{p}{}^1\text{)}{}^{12}\text{C}$ have been obtained at θ_γ = 0° and 90° and E_p = 610–2700 keV. Away from the 1699 keV resonance the capture γ-ray yield is dominated by the direct capture process E1 (p → s) to the $\text{2366 (}\text{1}\text{2}{}^{\mathrm{+}}\text{) keV}$ unbound state. Above E_p = 1 MeV, the observed excitation functions are well reproduced by the direct capture theory to unbound states (bremsstrahlung theory). Below E_p = 1 MeV, i.e., E_p → 457 keV, the theory diverges in contrast to observation. This discrepancy is well known in bremsstrahlung theory as the “infrared problem”. From the observed direct capture cross sections at $\text{E}{}_{\mathrm{p}}\text{? 1 MeV}$, a spectroscopic factor of C²S(l = 0) = 1.02 ± 0.15 has been found for the $\text{2366 (}\text{1}\text{2}{}^{\mathrm{+}}\text{) keV}$ unbound state. A search for direct capture transitions to the $\text{3512 (}\text{3}\text{2}{}^{\mathrm{?}}\text{)}$and $\text{3547 (}\text{5}\text{2}{}^{\mathrm{+}}\text{) keV}$ unbound states resulted in upper limits of C²S(l = 1) ≦ 0.5 and C²S(l = 2) ? 1.0, respectively. The results are compared with available stripping data as well as shell-model calculations. The astrophysical aspect of the ¹²C(p, γ₀)¹³N reaction also is discussed.     

Negative-parity states in Pb isotopes: g-factor of the 480 ns,if Jπ = 9− isomer in 200Pb

The g-factor of the 480 ns, 9^? isomer at 2.237 MeV in ²⁰⁰Pb was measured by the time-differential perturbed angular distribution method. The result, g = ?0.0285±0.0011 confirms the rather pure $\text{(}\text{f}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}{}^{\mathrm{?1}}\text{i}{}_{\mathrm{<mtext>13</mtext><mtext>2</mtext>}}{}^{\mathrm{?1}}\text{)}$ quasiparticle structure of this state. Half-lives of 480±20 ns, 43±3 ns and 42±4 ns have been measured for the 2237 keV 9^?, 2154 keV 7^? states in ²⁰⁰Pb and the 2208 keV state in ²⁰²Pb, respectively; E2 transitions and g-factors of negative-parity states in even, neutron-deficient Pb isotopes are discussed.     

12C(7Li,t)16O and stellar helium fusion

The reaction ¹²C(⁷Li, t)¹⁶O has been studied at $\text{E(}{}^7\text{Li}\text{) = 34}\text{MeV}$ with the LASL tandem accelerator and QDDD magnetic spectrometer. Angular distributions to levels with E_x < 11 MeV have been obtained from 0° to 90°, including 0°. The results have been analyzed with finite-range distorted-wave Born approximation theory. The α-particle spectroscopic factors and reduced widths obtained are compared with those calculated with group theory (SU(3)) and other models. The analysis of data for the 7.1 and 9.6 MeV J^π = 1^? levels, which are of great importance in stellar helium buring, yields a ratio, R, of dimensionless reduced α-widths $\text{θ}{}^2{}_{\mathrm{<mtext>a</mtext>}}\text{(7.1}\text{MeV}\text{)}\text{θ}{}^2{}_{\mathrm{<mtext>a</mtext>}}\text{(9.6}\text{MeV}\text{)}\text{= 0.35b ± 0.13}$. The observed line width of the 9.6 MeV level (Γ_c.m. = 390 ± 60 keV) is less than the accepted value (Γ_c.m. = 510 ± 60 keV) and implies θ²_a(9.6 MeV) ≈ 0.6. These results as well as data for the 6.92 MeV J^π = 2⁺ and 10.35 MeV J^π = 4⁺ “α-cluster” states indicate 0.09 < θ²_a(7.1 MeV) < 0.33 with a mean value θ²_a(7.1 MeV) = 0.14 ± 0.04. The implication for stellar helium burning is discussed.     

Decay of the mirror nuclide 45V

The β⁺ decay of ⁴⁵V $\text{(J}{}^{\mathrm{\pi }}\text{, T=}\text{7}\text{2}{}^{\mathrm{?}}\text{,}\text{1}\text{2}\text{)}$ has been observed. The half-life was found to be 539 ± 18 ms; in addition to the superallowed transition to the mirror state (⁴⁵Ti ground state), it exhibits a (4.3 ± 1.5)% allowed branch to the $\text{5}\text{2}{}^{\mathrm{?}}$ state at 40.1 keV in ⁴⁵Ti. Decay data for the complete $\text{f}{}_{\mathrm{<mtext>7</mtext><mtext>2</mtext>}}$ shell series of mirror nuclei are presented.     

Multipole mixing ratios of γ-transltions in 182W

γ-γ directional correlation experiments were performed on 14 cascades in ¹⁸²W populated from the β^? decay of ¹⁸²Ta(115 d). Two Ge(Li) detectors were used in a coincidence arrangement, and the ¹⁸²Ta sources were dissolved in HF acid to minimize extranuclear perturbations. For the 1189keV, 2^? → 2⁺ transition, the measured directional correlation coefficients are consistent only with multipole mixing ratios $\text{δ}\text{(}\text{M}\text{2}\text{E}\text{1)}\text{= 0.45 ± 0.03}\text{and}\text{δ}\text{(E3}\text{E1)}\text{= ?0.67 ± 0.07}$. These mixing ratios are discussed and compared with the known conversion coefficients for the 1189keV transition. The E2/M1 multipole mixing ratios determined are (energy in keV): δ(66) = 0.15 ± 0.15, δ(85) = 0.31 ± 0.05, δ(114) = 0.31 ± 0.05, 0.56 ≦ δ(179) ≦ 1.36, δ(1121) = 12⁺²_?1, and δ(1231) = ?(32⁺¹⁴²_?15). The measured M2/E1 mixing ratios are: δ(68) = 0.03 ± 0.02, δ(152) = 0.014 ± 0.013 and δ(156) = ?0.13 ± 0.19.     

Recoil-distance lifetime measurements in 51Cr, 53Cr, 53Mn and 53Fe

Levels in ⁵¹Cr, ⁵³Cr, ⁵³Mn and ⁵³Fe were excited via (α, n) or (α, p) reactions. Using the recoil-distance method, mean-lives (in ps) have been obtained for excited states (keV) in the residual nuclei: ${}^{51}\text{Cr}\text{(2256) = 66±2,}{}^{53}\text{Cr}\text{(1536) = 21.5±3.5,}{}^{53}\text{Cr}\text{(2173) = 6.7±3.1,}{}^{53}\text{Mn}\text{(2564) = 20}{}^{\mathrm{+8}}{}_{\mathrm{?6}}\text{and}{}^{53}\text{Fe}\text{(1424) = 4.0±1.0}$. Reduced transition probabilities calculated from these values are compared with the available theoretical values.     

The level structure of 184W FROM THE β− decay of 184Ta

Levels of ¹⁸⁴W populated in the decay of 8.7 h ¹⁸⁴Ta have been studied by a variety of experimental techniques. As a result of β and γ-ray energy and intensity determinations and extensive β-γ and γ-γ coincidence measurements, a detailed ¹⁸⁴Ta decay scheme accommodating more than 99.5% of the decay intensity has been established. Intense β-ray groups of end-point energies 1165±26 and 1123±26 keV populate levels in ¹⁸⁴W at 1699 and 1746 keV, which de-excite predominantly to the 8.3 μs isomeric level at 1285 keV, recently identified as the $\text{1}\text{2}{}^{\mathrm{?}}\text{[510]ν?}\text{11}\text{2}{}^{\mathrm{+}}\text{[615]ν K}{}^{\mathrm{\pi }}\text{= 5}{}^{\mathrm{?}}$ band origin. The 1699 keV level also de-excites to members of a $\text{1}\text{2}{}^{\mathrm{?}}\text{[510]ν?}\text{7}\text{2}\text{[503]ν K}{}^{\mathrm{\pi }}\text{= 3}{}^{\mathrm{+}}$ band based at 1425 keV. New information about the properties of the γ-vibrational and K = 2 octupole bands in ¹⁸⁴W is presented and the possible configurations of the levels directly populated in the β^? decay are discussed. The configuration $\text{7}\text{2}{}^{\mathrm{+}}\text{[404]π ?}\text{3}\text{2}{}^{\mathrm{?}}\text{[512]ν K}{}^{\mathrm{\pi }}\text{= 5}{}^{\mathrm{?}}$ is indicated for the ¹⁸⁴Ta ground state.     

High-spin states in 38K

High-spin states in ³⁸K are investigated with the ²⁴Mg(¹⁶O, pnγ)³⁸K reaction at $\text{E(}{}^{16}\text{O}\text{) = 36–44}\text{MeV}$. A recently developed Compton-suppression spectrometer with 120 msr solid angle and a pulsed beam are employed to study their γ-decay. For the E4 transition from the isomeric level at E_x = 3458 keV to the ground state a branching ratio of (0.15 ± 0.02)% is found. On the basis of angular distribution and polarization measurements, in which the delayed feeding component is eliminated, spin-parity assignments are obtained of J^π(2646 keV) = (2, 4)^?, J^π(3420 keV) = (4, 6)^? and J^π(3458 keV) = (5, 7)⁺. Prompt-delayed and prompt γγ coincidence experiments are performed to locate high-spin levels above the isomer. Hitherto unobserved levels of high spin are found at E_x = 5254, 7397, 8693, 8747 and 10980 keV and assignments of J^π = (9⁺), (10^?), (12^?), (11^?) and (13^?) respectively, are suggested by weak-coupling considerations. The experimental results are compared with a large-scale shell-model calculation performed in a configuration space with a ²⁸Si core and ten active particles distributed over the ($\text{2}\text{s}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{, 1}\text{d}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}\text{, 1}\text{f}{}_{\mathrm{<mtext>7</mtext><mtext>2</mtext>}}\text{, 2}\text{p}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}\text{)}$ shells. The high-spin states appear to have a rather simple shell-model structure.     

Band structures in 98Ru and 99Ru

The level schemes of ^{98, 99}Ru were studied with the reactions ⁹⁸Mo(α, 3nγ) and ⁹⁸Mo(α, 4nγ) at E_α = 35 to 55 MeV, using a large variety of in-beam γ-ray detection techniques and conversion-electron measurements. A search for the 3^? state was carried out with the reaction ⁹⁸Ru(p, p′). The ground-state band of ⁹⁸Ru was excited up to J^π = (12)⁺ and a negative-parity band up to (15)^?. New levels in ⁹⁸Ru were found at E_x = 2285 (J^π = 4⁺), 2435 (J^π = (3^?, 4⁺)), 2671, 3540, 4224, 4847, 4915 (J^π = (12)⁺), 4989 (J^π = (12⁺)), 5521 (J^π = (13)^?), 5889, 6591 (J^π = (15)^?), and 7621 keV. New unambiguous spin and parity assignments were made for the levels at E_x = 2014 and 3852 keV, as J^π = 3⁺ and 9^?, respectively. New levels in ⁹⁹Ru were found at E_x = 1976, 2021 ($\text{J}{}^{\mathrm{\pi }}\text{= (}\text{15}\text{2}{}^{\mathrm{+}}\text{)}$), 2393, 2401 ($\text{J}{}^{\mathrm{\pi }}\text{= (}\text{17}\text{2}{}^{\mathrm{+}}\text{)}$), 2875 (π = (+)), 3037, 3201 ($\text{J}{}^{\mathrm{\pi }}\text{= (}\text{23}\text{2}\text{)}{}^{\mathrm{?}}$), 3460 ($\text{J = (}\text{17}\text{2}\text{)}$), 3484 ($\text{J}{}^{\mathrm{\pi }}\text{= (}\text{21}\text{2}{}^{\mathrm{+}}\text{)}$), 3985, 4224 ($\text{J}{}^{\mathrm{\pi }}\text{= (}\text{27}\text{2}{}^{\mathrm{?}}\text{)}$), and 5359 keV. The 1070 keV, $\text{J}{}^{\mathrm{\pi }}\text{=}\text{11}\text{2}{}^{\mathrm{?}}$ level in ⁹⁹Ru has a half-life of 2.8 ns. A strongly excited negative-parity band is built on this level. A positive-parity band based on the ground state was excited up to $\text{J}{}^{\mathrm{\pi }}\text{= (}\text{21}\text{2}{}^{\mathrm{+}}\text{)}$. The level schemes are well reproduced by the interacting boson model in the vibrational limit.     

Lifetime and g-factor results for the 132− 1985 keV level in 91Nb and the 152− 2288 keV level in 91Zr

Lifetime and g-factor measurements have been made with pulsed beam-γ time-differential techniques using the ⁸⁹Y(α, 2n)⁹¹Nb and ⁸⁸Sr(α, n)⁹¹Zr reactions. A mean lifetime τ = 14.4 ± 0.5 nsec and a g-factor of 1.26 ± 0.04 were obtained for the $\text{13}\text{2}{}^{\mathrm{?}}$ 1985 keV level in ⁹¹Nb and τ = 41.9 ± 1.2 nsec and g = 0.70 ± 0.01 were obtained for the $\text{15}\text{2}{}^{\mathrm{?}}$ 2288 keV level in ⁹¹Zr. These results are compared to theoretical calculations for $\text{(π}\text{g}{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}\text{)}{}^2\text{(π}\text{p}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{)}$ and $\text{(π}\text{g}{}_{\mathrm{<mtext>9</mtext><mtext>2</mtext>}}\text{)(π}\text{p}\text{1}\text{2}\text{)(v}\text{d}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{)}$ configurations in ⁹¹Nb and ⁹¹Zr, respectively.     

Beta decay studies in the vicinity of 13250Sn82: Excited states in 13051Sb, 13052Te and 13252Te

Using the OSIRIS on-line isotope separator facility, the decays of ¹³⁰Sn and ^{130, 132}Sb have been studied. On the basis of singles γ and γ-γ coincidence Ge(Li) spectra and conversion electron Si(Li) measurements, level schemes for ¹³⁰Sb, ¹³⁰Te and ¹³²Te have been constructed. The corresponding half-lives have been measured using multiscaling technique. The 3.8 min ground state of ¹³⁰Sn populates only positive parity states in the πν^?3 nucleus ¹³⁰Sb: the energetically lowest 5⁺ state with the $\text{(π1}\text{g}{}_{\mathrm{<mtext>7</mtext><mtext>2</mtext>}}\text{, ν2}\text{d}{}_{\mathrm{<mtext>3</mtext><mtext>2</mtext>}}\text{)}$ configuration assignment; the $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{= 3.6 ± 0.3}\text{ns}\text{4}{}^{\mathrm{+}}$ state at 70.0 keV; the 2⁺ state at 262.5 keV; the (0, 1)⁺ state at 697.2 keV; the 3⁺ state at 813.1 keV and the 1⁺ state at 1042.3 keV excitation energy. A 1.7 min isomeric state in ¹³⁰Sn, with the tentative spin assignment (7^?), populates several odd parity levels in ¹³⁰Sb. These arise from the $\text{(π1}\text{g}{}_{\mathrm{<mtext>7</mtext><mtext>2</mtext>}}\text{, ν1}\text{h}{}_{\mathrm{<mtext>11</mtext><mtext>2</mtext>}}{}^{-1}\text{)}$ and/or $\text{(π2}\text{d}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}\text{, ν1}\text{h}{}_{\mathrm{<mtext>11</mtext><mtext>2</mtext>}}{}^{-1}\text{)}$ configurations and are located 84.7 keV (6^?), 144.9 keV (7^?), 688.5 keV and 1044.0 keV above the 40 min 8^? β- decaying state. No transitions between odd and even parity states have been observed.The most important excited states in ¹³⁰Te found in the β^? decay of the 6.6 min ¹³⁰Sb 5⁺ state are: 839.4 keV, 2⁺; 1632.8 keV, 4⁺; 1815.1 keV, 6⁺; 2100.8 keV, 5^?.Levels in the π²ν^?2 nucleus ¹³²Te were observed in the β^? decays of the 2.8 min ¹³²Sb (4⁺) and the 4.2 min ¹³²Sb (8^?) states. Unique spin and parity assignments have been given to the following states: 973.9 keV, 2⁺; 1670.7 keV, 4⁺; 1774.1 keV, 6⁺; 1924.7 keV, 7^?; 2053.0 keV, 5^?.     

Nuclear structure effect in internal conversion of the isomeric transition in 191Os

Measurements have been performed on relative conversion line intensities of the hindered 74.38 keV isomeric transition in ¹⁹¹Os with the $\text{1}\text{2}\text{π√13}$ iron-free β-ray spectrometer. Anomalies were observed for the L, M and N subshell intensity ratios and were explained with a nuclear structure parameter λ = 9.4 ± 0.5 and a mixing ratio $\text{¦δ(}\text{E4/M3}\text{)¦ = (3.0 ± 0.3) × 10}{}^{\mathrm{?3}}$.     

Investigation of rare non-strange decay modes of the f meson in Π+p interactions at 5GeVc

Rare decay modes of the f meson are studied in the final states Δ⁺⁺π⁺π^?π⁺π^?, Δ⁺⁺π⁺π^?MM and Δ⁺⁺π⁺π^?π⁺π^?MM. The ratio $\text{Γ (f → π}{}^{\mathrm{+}}\text{π}{}^{\mathrm{?}}\text{π}{}^0\text{π}{}^0\text{)}\text{Γ(f → π}{}^{\mathrm{+}}\text{π}{}^{\mathrm{?}}\text{)}$ is 0.23 ± 0.09 and Γ(f → 4 π) saturates the f inelasticity. A 2 s.d. upper limit of 0.09 is found for the branching ratio $\text{(f → ηη)}\text{(f → 2π)}$.