A New Level Scheme of 127I

Study of in beam γ ray spectroscopy of ¹²⁷I has been performed using ¹²⁴Sn(⁷Li, 4n)¹²⁷I reaction at 32 MeV beam energy. A new level scheme of ¹²⁷I has been established including 25 new levels and 52 new γ transitions. Negative parity levels based on 11/2^－ π h_11/2 particle state have been observed up to (35/2^－) extending our knowledge of decoupled structures to the heavier iodine isotope. Two ΔI=2 yrast positive-parity levels have been proposed to be associated mainly with the πg_7/2 configuration due to observations of several strong inter band transitions. Two weakly populated ΔI=2 positive parity levels and a high-lying ΔI=1 cascade have been newly identified and tentatively assigned as πd_5/2 one-quasiparticle and three quasiparticle bands, respectively.     

High-Spin Level Scheme of Odd-Odd 140Pr Nucleus

High spin level structure of doubly odd nucleus ¹⁴⁰Pr has been investigated using in beam γ spectroscopy techniques by means of the ¹³⁰Te(¹⁴N,4n)¹⁴⁰Pr reaction at beam energy of 58MeV.γ-ray excitation functions,γ-ray singles and γ-γ-t coincidences were measured experimentally.The level scheme of ¹⁴⁰Pr,including 27 new levels and 42 new γ-rays,was established for the first time up to 4717.3keV in excitation energy.Based on the measured γ-ray anisotropies,spin values were suggested to the levels in ¹⁴⁰Pr.Several quasiparticle configurations are discussed on the basis of systematics in the neighboring odd odd nuclei,and interpreted qualitatively.     

High-Spin Level Scheme of Odd-odd 142Pm

The level structure of doubly odd nucleus ¹⁴²Pm has been studied via the ¹²⁸Te(¹⁹F,5nγ)¹⁴²Pm reaction in the energy region from 75 to 95MeV. In-beam γ rays were measureed including the excited function, γ-ray singles and γ-γ coincidences in experiment. The level scheme of ¹⁴²Pm has been extended up to excitation energy of 7030.0keV including 25 new γ rays and 13 new levels. Based on the measured γ-ray anisotropies, the level spins in ¹⁴²Pm have been suggested.     

Decay of 95Ru

1.65h ⁹⁵Ru was produced and studied by y ray spectroscopy of ⁹²Mo(a, n)reaction, 34 of the 130 obversed y rays following ⁹⁵Ru decay are new. According to coincidence relations, 29 new γ rays were flited into level scheme, the placement of 7 γ rays in level scheme were confirmed, 3 new levels were assigned, a modified and expanded decay scheme was proposed.     

Level Scheme of High-Spin States in 145Tb

High-spin states of ¹⁴³Tb have been studied via the ¹¹⁸Sn(³²S,1p4n)¹⁴⁵Tb reaction by means of in-beam γ-ray spectroscopy. Measurements of γ-ray excitation functions and γ-γ-t coincidences were performed with 12 BGO(AC)HPGe detectors. A level scheme for ¹⁴⁵Tb including 41 γ-rays which come from the deexcitations of the 24 levels, has been established for the first time based on an analysis of the γ-ray excitation functions, γ-γ coincidence relationships, intensity balances and cross-over transitions. The spins for most of the levels in the scheme are assigned according to the results of the measured γ-ray anisotropies. Considering the structure similarity between ¹⁴³Eu and ¹⁴⁵Tb, the low-lying levels in 145Tb are interpreted by coupling a h_9/2 proton to the excited states in ¹⁴⁴Gd core.     

High Spin States and Shape Coexistence in 134Ce

high spin states in ¹³⁴Ce nucleus have been studied by using the heavy–ion induced reaction ¹²²Sn(¹⁶O,4n) carried out at china institute of atomic energy. the early level scheme has been extended with spin up to 22. however,our result is different from that in a recent publication,and the magnetic rotation bands reported there have not been confirmed. our observed level structures may be interpreted as shape coexistence. the 10+ state at the backbending with h_11/2 quasineutron configuration has an oblate deformation with an asymmetry parameter γ≈–60°(lund convention),and the 10+ isomer is a yrast trap of prolate deformation with γ≈–120°,whereas the other signature partner bands with h_11/2 and g_7/2 proton configuration probably have a prolate deformation with γ≈0°.     

Lifetime Measurements of the States Around the Backbend in 126Ba

The high spin states in ¹²⁶Ba were populated by means of the reaction ¹¹⁶Sn (¹⁶O,2p4n)¹²⁶Ba at the beam energy of 73MeV. Lifetimes of the states around the backbend in the yeast band were measured by using the Doppler shift attenuation method. The corresponding normalized B(E2) values are pronouncedly reduced for the 10⁺ and 12⁺ states. The experimental results are compared with the theoretical predictions of the particle-rotor model.     

OBSERVATION OF EXCITED STATES IN 128Ba

Excited states of ¹²⁸Ba are investigated via the ¹²⁰Sn(¹²C, 4nγ) ¹²⁸Ba reaction by means of in-beam gamma spectroscopy Λ 12⁺ state other than the previously reported one is observed according to the properties of the 935.0keV γ-ray. It does not belong to the ground state band. Two new interband transitions, 224.8keV and 632.7keV, are observed and assigned to sidefeeding between the negative-parity band and ground state band.     

In-beam study of the doubly-odd nucleus 61 140 Pm79

A detailed -γ-ray study of¹⁵²Dy has been performed using the¹²⁴Sn(³²S,4n) reaction at low bombarding energy. Several γ rays deexciting non-Yrast states have been identified, among them transitions previously observed in coincidence with the superdeformed band. However we have no evidence for the lowest members of this band.     

Collective Bands in Neutron-Rich 107Ru Nucleus

Through measuring prompt γ-rays emitted in the spontaneous fission of ²⁵²Cf with higher statistic data,level structures in the neutron rich,odd A¹⁰⁷Ru nucleus have been re investigated. New level scheme of ¹⁰⁷Ru has been established. The ground state band was extended with spin up to 27 2h. The νh_11/2 band structure observed in our previous publication has been confirmed and extended. These results clear up the inconsistence between our earlier work and results from another experiment published recently. A collective band built on (9/2^－) level has been observed for the first time. Some important features of the level scheme have been discussed.     

New Low-spin Levels in 76Se and Discussion of Its Yrast Band Structure

The decay of bromine–76 was studied using compton–suppressed spectrometer and high–purity ge detectors in singles and coincidence mode, respectively. bromine–76 was produced via two reactions,i. e.,⁷⁵As(α,3n)⁷⁶Br and ⁷⁶Se(p, n)⁷⁶Br.the results of these experiments verified the previously reported levels and gammas of ⁷⁶Se. in addition to the previously described transitions and levels, 39 new γ–rays and 15 new energy levels were found for the first time. spins and parities for new levels are proposed based on the calculated logft values, de–excitation modes of the observed states, and some nuclear reaction experiment results. a new decay scheme of ⁷⁶Br is proposed in the present work. combining with the high–spin states observed by the in–beam γ–ray spectroscopy of a previous decay work, the positive–parity yrast states were compared with the results from calculations in the framework of the projected shell model.     

The level scheme of91Nb from the reaction90Zr (p, γ)91Nb

The level scheme of⁹¹Nb has been investigated with the reaction⁹⁰Zr(p, γ)⁹¹Nb. Proton energies between 3.0 and 7.2 MeV were used. The γ spectra were taken with Ge(Li) detectors. Primary γ transitions to 36 excited states of⁹¹Nb up to 3.8 MeV excitation energy and many secondary γ transitions from the decay of those states were observed, leading to an extension of the known level scheme. The proton binding energy for⁹¹Nb was determined as (5167± 5) keV. Eleven γ transitions in⁹⁰Zr, part of them new, from the competing reaction⁹⁰Zr(p, p′ γ) were also observed.     

Low-lying states of 109Sn from the 106Cd(α, nγ) reaction

Measurements of γ-ray, γγ-coincidence and internal conversion electron spectra from the ¹⁰⁶Cd(α, nγ)¹⁰⁹Sn reaction were carried out at 15–20 MeV α-particle bombarding energies with Ge(HP) γ-ray and superconducting magnetic lens plus Si(Li) electron spectrometers. The energies, relative intensities, internal conversion coefficients and coincidence relations of the ¹⁰⁹Sn transitions were determined, and a more complete, consistent level scheme has been deduced. Spin and parity values have been determined from the internal conversion coefficients, the bombarding-energy dependence of the side-feeding intensities of the states and the available γ-ray angular distribution data. The level scheme was interpreted in the framework of the quasi-particle shell model.     

A New Isomer State in 136Ba

The reaction of ¹³⁹La(⁸²Se, x)¹³⁶Ba was used in this experiment. The nuclide ¹³⁶Ba was produced via the transfer reaction channel. Some new γ rays of ¹³⁶Ba were measured and a new isomer state at 10⁺ was observed. The half life of this isomer is 94ns based on its time spectrum. According to the intensities of gamma transition and gamma-gamma coincidence relationship, the scheme of ¹³⁶Ba is suggested.     

High spin structures of 122Xe

High — spin states in ¹²²Xe have been investigated by γ ? γ coincidence measurements using the EUROGAM array. The reaction ⁹⁶Zr(³⁰Si,4n)¹²²Xe at a beam energy of 135 MeV was used to populate states of ¹²²Xe. The level scheme has been extended up to ～ 13.5 MeV and also enriched as compared to previous studies. New structures of competing dipole to quadrupole transitions have been observed. Experimental B(M1)/B(E2) ratios have been extracted for these structures and compared with theoretical estimates. They have also been compared with similar structures in Xe, Ba and Ce nuclei.     

Experimental Evidence for the Superdeformation in 81Rb

High-spin states in ⁸¹Rb were populated in the ⁵⁵Mn(³⁰Si, 2p2n) reaction at 130 MeV. Prompt γγγ-charged particle coincidences were observed using the GASP spectrometer in conjunction with the ΔE-E silicon ball (ISIS). A superdeformed band consisting of seven γ-ray transitions has been identified. The dynamic moment of inertia for the band is constant with a value of approximately 26.7 h²/MeV throughout the whole observed rotational frequency. This band is interpreted to have a π5¹v5² intrinsic intruder configuration with a quadruple deformation β₂ of 0.51.     

214Po: A γ-γ and γγ(θ) Coincidence study

Extensive γ-γ coincidence measurements have been made on γ rays accompanying theβ ^? decay of²¹⁴Bi using a conventional GeGe coincidence spectrometer. A total of 33 new γ transitions among levels of²¹⁴Po have been established. Twenty-three previously reported but unplaced transitions have now been assigned in the level scheme. In addition to confirming 56 previously proposed levels, four new levels are established at 1015.05, 1712.98, 3003.5 and 3160.5 keV. Directional correlation measurements have been made on six weak cascades which have the first excited state in common. Mixing ratios have been deduced for the transitions concerned.     

Study on the Excited States of 124Cs by Heavy Ion Reaction

Excited states of ¹²⁴Cs have been studied by means of in beam γ-ray technique via the reaction ¹⁰⁹Ag(¹⁹F,p3n).Based on the observation of the high spin bands and their decay to the ground state,a level scheme of ¹²⁴Cs has been established.     

Level sructure in 206At

The high-spin states of ²⁰⁶At have been studied in the reaction ¹⁹⁷Au (¹²C,3n) ²⁰⁶At at ¹²C energies from 60 to 80 MeV. In-beam measurements of %-ray excitation functions, %-%-t coincidences, and %-ray angular distributions were carried out with seven BGO(AC)HPGe detectors and one intrinsic Ge planar detector. A level scheme for ²⁰⁶At with 25 % rays was established for the first time, including a 10^m isomer with a measured half-life of 410 - 80 ns. The level scheme of ²⁰⁶At consists of two disconnected cascades, probably corresponding to the proton excitations and the neutron-hole excitations, respectively.     

Spectroscopic study of the 54Fe(16O,pn)68As reaction

Low and high states of the doubly odd nucleus ⁶⁸As have been studied through in-beam γ spectroscopy via the ⁵⁴Fe(¹⁶O, np) reaction. A new level scheme for the ⁶⁸As nucleus was determined on the basis of the neutron-γ and neutron-γγ coincidences,excitation functions, angular distributions and linear polarisation. New spins, parities and γ-decay properties were established.