Revisiting band structures in^(118)Xe nucleus via in-beamγ-ray spectroscopy

The neutron deficient Xe nuclei with A≈120 are predicted to have strong octupole correlation at low spins.In the present study,an attempt was made to improve upon the level scheme and also to examine the signatures of octupole correlation in^(118)xe via high spin γ-ray spectroscopy.High spin states in^(118)Xe have been populated via the^(93)Nb(^(28)Si,p2n)^(118)Xe fusion-evaporation reaction at a beam energy of 115 MeV provided by the 15 UD pelletron accelerator facility at IUAC,New Delhi.In the experiment,seven newγ-transitions have been found and placed appropriately in the level scheme.A theoretical study using the triaxial projected shell model(TPSM)approach suggests that the first bandcrossing is due to the alignment of two neutrons,and a parallel band tracking the yrast configuration is the γ-band built on the two-quasiparticle state.Enhanced E1 transition rates measured between opposite parity bands involving vh_(11/2)and vd_(5/2)orbitals having△j=△l=3 indicate the presence of octupole correlation in this nucleus.

γ-ray Spectroscopy of Hypernuclei:Recent KEK Results and Future Plans at J-PARC

In this proceeding,we will first outline the experimental setup and main results of the most recent hypernuclear γ-ray spectroscopy experiment (KEK-E566) performed at KEK-PS K6 beam line. The main feature and characteristics of this type of research will be emphasised. After that,the approved experimental proposal (E13) at J-PARC facility will be introduced briefly.

Mass Yield Distribution in Intermediate Energy Heavy Ion Reactions

The production cross sections of the target residues were measured for the 40 MeV/u40Ar+Cu reaction by γ-ray spectroscopic technique and the mass yield distribution was deduced.The ex-perimental data were compared with the theoretical results from both the GEMINI code based on the statis-tical binary decay model and the McFRAG code based on the fusion-fragmentation model.

Comprehensive analysis of uncertainty quantification for the^(58)Ni(n,p)^(58)Co reaction cross section

In this study,we measured the^(58)Ni(n,p)^(58)Co reaction cross section with neutron energies of 1.06,1.86,and 2.85 MeV.The cross section was measured using neutron activation techniques andγ-ray spectroscopy,and it was compared with cross section data available in the EXFOR.Furthermore,we calculated the covariance matrix of the measured cross section for the aforementioned nuclear reaction.The uncertainties of the theoretical calculation for^(58)Ni(n,p)^(58)Co reaction cross section were calculated via Monte Carlo method.In this study,we used uncertainties in the optical model and level density parameters to calculate uncertainties in the theoretical cross sections.The theoretical calculations were performed by using TALYS-1.96.In this study,we aim to analyze the effect of uncertainties of the nuclear model input as well as different experimental variables used to obtain the values of reaction cross section.

Cross-sections of the ^(238)U(n,γ) ^(239)U reaction in the 3.0-7.0 MeV energy region measured by relative activation method

The reaction cross-sections of^(238)U(n,γ)^(239)U have been experimentally determined at neutron energies of6.117±0.119 MeV,4.626±0.086 MeV,and 3.622±0.348 MeV employing the relative activation approach along with the off-line γ-ray spectroscopy method.The D(d,n)3He reaction was utilized to obtain monoenergetic neutrons of the required energy,and the^(197)Au(n,γ)^(198)Au reaction cross-sections were adopted as the referential standard to ascertain the neutron capture cross-sections of^(238)U.Furthermore,the effects of low-energy scattered neutrons,neutron fluence fluctuations,counting of geometric corrections when measuring γ-rays,and neutron and γ-ray self-absorption caused by the sample thickness have been considered and revised in the present work.For a comparison with experimental results,the cross-sections of the^(238)U(n,γ)^(239)U reaction were calculated theoretically with the original parametric TALYS-1.9 program.The experimental measurements were in contrast to previous experimental re sults and the evaluation data available for ROSFOND-2010,CENDL-3.2 and ENDF/B-VIII.0.

Shape co-existence and structural evolution of the vi_(13/2) band in ^(157)Yb

The high-spin states of 157Yb have been studied via the reaction of 144Sm(16O, 3n) at 16O energy of 90 MeV using techniques of in-beam γ-ray spectroscopy. Measurement of γ-γ-t coincidences was performed with 11 BGO(AC)HPGe detectors. Based on the γ-γ coincidence relationships and the measured results of γ-ray anisotropies and DCO ratios, the level scheme for 157Yb was established. The shape co-existence and structural evolution of the Vi13/2 band with increasing angular momentum in 157Yb have been discussed. The systematics of the Vi13/2 bands in the N = 87 odd-A isotones have been compared.

High-spin states of ^(125)Sb:Particle-core excitation coupling

Excited states of125Sb have been studied using in-beam γ spectroscopy techniques via the124Sn(7Li, α2n) reaction at a beam energy of 32 MeV. A high-spin level scheme including 21 new γ-transitions and 14 new excited states have been established. Three isomers have been identified at 1970, 2110 and 2471 keV and the ranges of their half-lives have been estimated from the delayed coincidence data. The level structure of125Sb is discussed in terms of particle-core excitation coupling. With the help of empirical shell model calculations the three isomers are proposed to have three-quasiparticle πg7/2?v(h 11/2 s 1/2)5?, πg7/2?v(h 11/2 d 3/2)7? and πg7/2?v(h 11 2/2 )10 + configurations, respectively.

Shears bands in ^(112)In

A new level scheme of 112In have been established up to 6.8 MeV in excitation energy and to a tentative spin of (21+) through the reaction 110Pd(7Li,5n)112In at a beam energy of 50 MeV. In-beam measurements involving γ-γ coincidences and directional correlation of oriented states were performed. M1 bands consisting of I =1 dipole transitions have been observed. Possible quasiparticle configurations suggest that these bands are similar to the shears bands observed in Pb nuclei.

High-spin states in ^(190)Pt

The level structure of ^19Opt has been studied experimentally using the ^176yb （^18O, 4n） reaction at beam energies of 88 and 95 MeV. γ-γ-t coincidence measurements were carried out. Based on the analysis of T-T coincidence relationships, the level scheme of ^190Pt is extended to high-spin states. A new structure built on the 3413.6 keV 14＋ state has been observed, and the ＂vi13/2^-2 vh9/2^-1 vj （j = P3/2 or f5/2） configuration is tentatively assigned to it.