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The high spin structure of 108Ag nucleus has been studied using the reaction 11B + 100Mo at 39 MeV with Indian National Gamma Array (INGA) at TIFR-BARC accelerator facility. From the two- and higher-fold coincidence analysis of the emitted γ-rays, the level structure of the nucleus is built, with addition of around ∼ 60 new transitions. A new positive parity dipole band has been observed and significant additions have been made in the low spin region. A pair of nearly degenerate, negative parity, dipole bands is established, which is studied using the triaxial projected shell model (TPSM).

The structural features of the 72Se nucleus, obtained from our recent work [1], have been compared with the neighboring eveneven proton rich Se isotopes to get a better understanding about the presence of shape coexistence at low spin states. The corresponding alignment behaviour of different Se isotopes has been used to understand the shapes of the coexisting states at low excitation energy. The experimental results of Se isotopes have been interpreted in the framework of total Routhian surface (TRS) calculations. [ABSTRACT FROM AUTHOR]

We present here a comparative analysis of even-even Ge isotopes to further understand the -vibrational bands and E(5) critical point symmetry based on our recent study on 68Ge nucleus [1]. The properties of 64-72Ge isotopes displaying the characteristics of γ -band have been discussed in terms of energy systematic and variation of R(J)γ,gr parameter. Further, the possibility of the presence of U(5), O(6), and E(5) critical point symmetry in different Ge isotopes are predicted on the basis of experimental level energy ratios of the low lying states. The experimental results of 66,68Ge nucleus are interpreted in terms of interacting boson approximation (IBA) calculations to test the possible existence of E(5) critical point symmetry. [ABSTRACT FROM AUTHOR]

Band structures of 99Rh nucleus are discussed in framework of the spherical shell-model calculations using the jj45pna effective interaction. Level structures at low energies are identified as resulting from the rotational bands based on the πp1=2 and πg9=2 configurations. The lowest observed positive-parity state is 9/2+ and corresponds to wave function consisting of the π(p1/2² g9/25 )configuration. Systematics of single-quasiparticle πp1/2 and πg9/2 bands in odd-A 91-113Rh isotopes along with the ground state bands in the corresponding even-even Ru core isotopes is discussed to bring out the role of spin-orbit partner orbitals for collectivity. The energy staggering plots for odd-A 91-113Rh isotopes are also discussed. [ABSTRACT FROM AUTHOR]

A comprehensive study of the low-lying states of 108Ag, near the isomeric state at Ei = 110 keV with Jπ = 6+ and T1/2 = 438 y, has been presented. Spectroscopy of these states has been carried out using the reaction 100Mo(11B, 3nγ)108Ag at 39 MeV beam energy using INGA. The multipolarities and electromagnetic nature of the transitions have been assigned based on the angular correlation and polarization measurements. The experimentally identified states have been compared to the results of the Projected Hartree-Fock calculations to understand the configurations involved in these states. [ABSTRACT FROM AUTHOR]

Medium-spin states in 122Te have been populated using the reaction 116Cd ( 11B, p4n) 122Te at a beam energy of 65MeV and $ \gamma$ - $ \gamma$ coincidences were measured using the INGA spectrometer. The previously known level scheme has been extended to spin $ \sim 23\hbar$ with the observation of the maximally aligned state at spin 22 +. The experimental results are compared with the shell model calculations. The configurations of the energy levels and terminating states are discussed. [ABSTRACT FROM AUTHOR]

Our work focuses on precision measurements of β-V correlation from the β -decay of 6He by the use of an innovative ion trapping device, the Electrostatic Ion Beam Trap, which incorporates the radioactive ion beam, ion trapping, ion bunching, and a radiation detection system. Production of 6He radioisotopes would be carried out by the use of neutron-induced reactions and for the ionization an Electron Beam Ion Trap would be used. [ABSTRACT FROM AUTHOR]

High spin states of 109In were investigated using the reaction 96Zr(19F, 6n)109In at a beam energy of 105 MeV. New level sequences have been found in this nucleus. In an earlier known band, the ordering of some of the transitions have been changed and assigned a three-quasiparticle &pai;(g9/2)-1 ⊕ v[h11/2(d5/2/g7/2)] configuration. Similar three-quasiparticle bands have also been found earlier in lighter mass 105In and 107In nuclei. Systematics of these bands in 105In, 107In, and 109In nuclei are discussed in the present work within the framework of the tilted axis cranking model. [ABSTRACT FROM AUTHOR]

We have performed shell model calculations for neutron deficient even 102-108Sn and odd 103-107Sn isotopes in sdg7/2h11/2 model space using two different interactions. The first set of interaction is due to Brown et al. and second is due to Hoska et al. The calculations have been performed using doubly magic 100Sn as core and valence neutrons are distributed over the single particle orbits 1g7/2, 2d5/2, 2d3/2, 3s1/2 and 1h11/2. In more recent experimental work for 101Sn [I. G. Darby et al., Phys. Rev. Lett.105 (2010) 162502], the g.s. is predicted as 5/2+ with excited 7/2+ at 172 keV. We have also performed another two set of calculations by taking difference in single particle energies of 2d5/2 and 1g7/2 orbitals by 172 keV. The present state-of-the-art shell model calculations predict fair agreement with the experimental data. These calculations serve as a test of nuclear shell model in the region far from stability for unstable Sn isotopes near the doubly magic 100Sn core. [ABSTRACT FROM AUTHOR]

High spin states in 112In were investigated using the 100Mo(16O, p3n) reaction at 80 MeV. The excited level has been observed up to 5.6 MeV excitation energy and spin ∼207&hstroke; with the level scheme showing three dipole bands. Polarization and lifetime measurements were carried out for the dipole bands. Tilted axis cranking model calculations were performed for different quasiparticle configurations of this doubly odd nucleus. Comparison of the calculations of the model with the B(M 1) transition strengths of the positive- and negative-parity bands firmly established their configurations. [ABSTRACT FROM AUTHOR]

Complete and incomplete fusion cross-sections for the 9Be + 124Sn system have been measured around the Coulomb barrier energies (EC.Blab = 28 MeV) using the on-line gamma ray detection technique. The complete fusion cross-sections of this system have been compared with the two stable projectiles on the same 124Sn target to provide information on the projectile dependence. The brief comparison of the present 9Be + 124Sn data with a comprehensive and recent study of the neighbouring system 9Be + 144Sm is also given. [ABSTRACT FROM AUTHOR]

A study of recently-measured high spin states of 75Kr is carried out by using the Projected Shell Model. Calculations are performed up to spin I = 33/2 for the positive parity band and I = 27/2 for the negative parity band. Irregularities found in moment of inertia and in the deduced transition quadrupole moments Qt of the two bands are discussed in terms of the alignment of g9/2 protons. Our study provides an insight into the shape evolution of the well-deformed nucleus 75kr. [ABSTRACT FROM AUTHOR]

The article presents a study that analysis and measures the contributions of the journal in the research field of animals and allied sciences. Several factors were considered for analysis which include authorship patterns of articles, illustrations, and global productivity. The analysis projects that maximum number of published articles was from "Animal Genetics & Breeding" at 19.77%, while minimum articles were from "Biochemistry" at 0.87%.

High-spin states in the 73Br nucleus have been populated via the 50Cr(28Si,αp)73Br fusion evaporation reaction with a beam energy of 90 MeV. The deexciting gamma rays were detected using the Indian National Gamma Array (INGA). Using the γ-γ coincidence technique, two new bands and eight new interconnecting transitions have been added. The strong interconnecting E1 transitions, between positive and negative parity bands, ensure the existence of octupole correlations at low spin. Line shapes have been observed for 17 transitions, which were analyzed by the Doppler-shift attenuation method to determine the lifetime of excited states of the yrast negative parity band and its signature partner band along with the positive parity band. The deduced transitional quadrupole moments Qt for the ground state band decrease with increasing spin, with their values ranging from 2.88 to 1.00 eb. A similar trend in the quadrupole moment has also been observed for the signature partner as well as for the positive parity band. This decrease in Qt with increasing spin for these bands is interpreted in terms of the cranked Nilsson-Strutinsky model and total Routhian surface calculations, which indicate possible band termination at higher spin. [ABSTRACT FROM AUTHOR]

Abstract: The lifetimes of high spin states of 75Kr have been determined via 50Cr (28Si, 2pn) 75Kr reaction in positive parity band using the Doppler-shift attenuation method. The transition quadrupole moments deduced from lifetime measurements have been compared with 75Br. Experimental results obtained from lifetime measurement are interpreted in the framework of projected shell model. [Copyright &y& Elsevier]

The high-spin states in 86 Sr nucleus were populated using the 76 Ge( 13 C, 3n) reaction at a beam energy of 45 MeV. The γ – γ and γ – γ – γ coincidence measurements were used to establish the level scheme up to 10.9 MeV excitation energy and spin I π = 19 + . In our preliminary results reported earlier, a positive-parity dipole ( Δ I = 1 ) band based on the 6878-keV level having M1 γ -ray transitions was identified. In the present work, the γ -rays and their sequence have been established for this band. The band may have a magnetic rotational character. The spin-parity of the levels were assigned by measuring the Directional Correlations of the Oriented (DCO) nuclei and the polarization asymmetry. The polarization measurements were performed for the first time for the γ -ray transitions in this nucleus. The experimental band structures were compared with the shell-model calculations using two recent effective interactions, JUN45 and jj44b in the 1 p 3 / 2 , 0 f 5 / 2 , 1 p 1 / 2 , 0 g 9 / 2 model space. From the Tilted-Axis Cranking (TAC) calculations, the 4-qp π ( g 9 / 2 ) 2 ⊗ ν ( g 9 / 2 ) − 2 configuration is suggested for the lower-part of the ( Δ I = 1 ) band up to spin I π = 16 + and the 6-qp π [ ( g 9 / 2 ) 2 ( f 5 / 2 ) 1 ( p 1 / 2 ) 1 ] ⊗ ν ( g 9 / 2 ) − 2 configuration for the upper-part of the band. [ABSTRACT FROM AUTHOR]

Lifetimes of the states in the quadrupole structure in 143 Eu have been measured using the Doppler shift attenuation method and the parity of the states in the sequence has been firmly identified from polarization measurements using the Indian National Gamma Array. The decreasing trends of the deduced quadrupole transition strength B ( E 2 ) with spin, along with increasing J ( 2 ) / B ( E 2 ) values before the band crossing, conclusively establish the origin of these states as arising from antimagnetic rotation. The abrupt increase in the B ( E 2 ) values after the band crossing in the quadrupole band, a novel feature observed in the present experiment, may possibly indicate the crossing of different shears configurations resulting in the re-opening of a shears structure. The results are reproduced well by numerical calculations within the framework of a semi-classical geometric model. [ABSTRACT FROM AUTHOR]

The 29Si nucleus has been studied using heavy-ion-induced fusion-evaporation reactions and, for the first time, using a large array of high-resolution ?-ray detectors. High-spin states of the nucleus are populated using 18O(16O,an) and 18O(13C,2n) reactions at Elab=30-34 MeV. Previously reported levels are confirmed and a new level is identified in the present study. Spin-parity assignments are carried out based on the anisotropy and polarization measurements of the observed ? transitions. Level lifetimes are measured using the Doppler shift attenuation method, with modified analysis techniques for the thick molecular target (Ta2O5) used in the present setup. The lifetime of the lowest negative-parity state at Ex=3624 keV is substantially modified from the previously reported value. Large-basis shell model calculations are carried out for the nucleus using updated interactions and the results corroborate the experimental findings. The calculations are also carried out for the neighboring 28,30Si isotopes. In the case of the 28Si nucleus, the calculations adequately reproduce most of the deformed structures, as represented by the quadrupole moments extracted therefrom. In the 30Si nucleus, the negative-parity states are reproduced for the first time without any ad hoc lowering of the single-particle energies. It can be generally stated that the shell model calculations adequately describe the experimental observations in these nuclei. [ABSTRACT FROM AUTHOR]

High spin states in 105Cd were studied using 92Mo(16O, 2pn)105Cd reaction at an incident beam energy of 75 MeV. The level scheme of 105Cd has been observed up to Jπ = (47/2-) and excitation energy ~10.8MeV with the addition of 30 new γ transitions to the previous work. Spin and parity for most of the reported levels are assigned from the directional correlation orientation (DCO) ratios and linear polarization measurements. The microscopic origin of the investigated band structures is discussed in the context of triaxial projected shell model (TPSM). The energies of observed positive- and negative-parity bands agree with the predictions of the TPSM by considering triaxial deformation for the observed excited band structures. The shape evolution with increasing angular momentum is explained in the framework of cranked shell model (CSM) and the total Routhian surface (TRS) calculations. [ABSTRACT FROM AUTHOR]

A high-spin study of the shape transitional nucleus 188 Pt reveals the unusual coexistence of both shape- and K -isomeric states. Reduced B ( E2 ) transition probabilities for decays from these states inferred from the data clearly establish their hindered character. In addition to other excited structures, a rotational band built upon the K isomer is identified, and its configuration has been assigned through an analysis of alignments and branching ratios. The shape evolution with spin in this nucleus has been inferred from both experimental observables and cranking calculations. The yrast positive parity structure appears to evolve from a near-prolate deformed shape through triaxial at intermediate excitation, and eventually to oblate at the highest spins. [ABSTRACT FROM AUTHOR]

High spin states in the 85Sr nucleus were populated in the reaction 76Ge(13C,4n) at a beam energy of 45 MeV. The ?-? and ?-?-? coincidence measurements have been utilized to establish the level scheme of 85Sr up to Ip=35/2-. Nearly 50 new ? rays and about 25 new levels were identified and most of the previously known levels confirmed. The spin-parity assignment of the levels was made by using the directional correlations of the oriented nuclei ratios and polarization asymmetry measurements. The shell-model calculations have been performed by using two recent interactions, JUN45 and jj44b, for a detailed comparison between theoretical results and the experimental data obtained in the present work. The shell-model results are in good agreements with the experimental data and are able to explain the various features such as the odd-even staggering well. Tilted axis cranking calculations were also performed to understand the magnetic rotation (MR) phenomenon at higher spins. One of the positive-parity ?I=1 bands has been assigned a three-quasiparticle (3qp) configuration, which appears to behave like a MR band. A negative-parity band populated up to Ip=35/2- was also assigned a 3qp configuration at low spin and a five-quasiparticle configuration at high spin; however, it does not exhibit the expected MR features, in contrast to a similar band in the 83Kr nucleus. [ABSTRACT FROM AUTHOR]

High-spin dipole structures in l43Eu have been studied via the fusion-evaporation ll6Cd (31P, 4n) reaction at a beam energy of 148 MeV using a clover detector array (Indian National Gamma Array). The parity of the two observed dipole bands has been firmly established from linear polarization measurements. Level lifetimes of these bands have been measured using the Doppler shift attenuation method. The drop in B(M1) values with spin exhibits a clear signature of the magnetic rotational character of these two bands. Configurations were assigned to the bands in the framework of the shears mechanism with the principal axis cranking model calculation. Alignment of an additional proton in the h11/2 orbital gives rise to the unique observation of a large increase in the B(M1) values for the higher-lying band. [ABSTRACT FROM AUTHOR]

The article presents a study which was carried out to analyze high spin band structure of Strontium isotopes and its excited energy state. Topics discussed include spin-parity assignment by using the directional correlations of oriented nuclei ratios and polarization asymmetry measurements, use of shell-model calculations in the study and tilted axis cranking calculations performed to understand the magnetic rotation (MR) phenomenon.

The article offers information on a study related to the use of shell-model and tilted axis cranking (TAC) model to calculate high spin (HS) states of 3885strontium (Sr)47. Topics discussed include the use of TAC to understand magnetic rotation (MR) phenomenon at HS, quasiparticle configuration at HS and spin-parity assignment of nuclear levels. Other topic discussed include determination of electromagnetic character of nuclear transitions for the study.

The article focuses on a study related to the use of shell-model and tilted axis cranking (TAC) model to calculate high spin (HS) states of Strontium (Sr) 3885Sr47. Topics include the use of TAC to understand magnetic rotation (MR) phenomenon at HS, quasiparticle configuration at HS and spin-parity assignment of nuclear levels.

The article presents a study that investigates the high spin band structure of 3885Strontium(Sr)47. Topics include utilization of double gamma coincidence measurement to establish the proper level scheme of 85Strontium(Sr), using the directional correlations of the oriented nuclei ratios and polarization asymmetry measurements to make spin-parity assignment of the levels, and understand the magnetic rotation (MR) phenomenon at higher spins.

The article presents brief information on high spin band structure of Strontium atom. It discusses that γ-γ and γ- γ-γ coincidence measurements have been utilized to establish for Strontium atoms. Topics discussed include shell-model calculations, magnetic rotation (MR) phenomenon at higher spins, and five-quasiparticle configuration.

Yrast and near-yrast states in odd-A 89Nb were investigated using the 65Cu(28Si,2p2n) reaction at a beam energy of 105 MeV. The y-ray coincidence events were recorded with the Indian National Gamma Array spectrometer. About 30 new transitions have been observed extending the level structure of this nucleus up to spin 45/2ħ and excitation energy of 10.5 MeV. Large-scale shell model calculations were performed using the effective interactions JUN45 and jj44b to understand the structure of the observed states. Reasonable agreement between the experimental observation and shell model calculations suggests that no cross-shell excitations are important up to the maximum spin observed in the current experiment. [ABSTRACT FROM AUTHOR]

The electric quadrupole transition rates for the high-spin yrast states of l04Pd have been measured by using the Doppler-shift attenuation method. These values decrease with the increase of angular momentum, which can be associated with the phenomenon of antimagnetic rotation. In the present work, a numerical calculation based on the semiclassical particle plus rotor model for antimagnetic rotation has been employed, giving a good description of the experimental Routhian and the transition rates and providing conclusive evidence of antimagnetic rotation in a nucleus other than cadmium. [ABSTRACT FROM AUTHOR]

High spin states of 88Zr were populated with 80Se(l3C, 5n) fusion evaporation reaction. A thin target as well as Au backed target were used in two different experiments for the present study. Excited levels of 88Zr have been observed up to spin ~20ħ and an excitation energy of ~10 MeV. Spin and parity of most of the states have been determined from directional correlation and polarization measurements. The level scheme was substantially extended with the addition of a number of high spin states and transitions. The comparison of the measured levels of 88Zr with large shell model calculations based on the full unrestricted f5/2Pg9/2 model space established the dominance of shell-model excitation up to the highest observed spin. [ABSTRACT FROM AUTHOR]

Nuclear structure of the 26Mg nucleus has been probed, for the first time, using heavy-ion-induced fusion-evaporation reaction and a large array of high-resolution γ-ray detectors (Clovers). The level structure of the nucleus reported in the earlier studies, using light-ion reactions, has been re-examined and new transitions have been identified. Existing spin-parity assignments have been confirmed and new assignments have been made from anisotropy and polarization measurements. Large basis shell-model calculations, involving cross-shell excitation-have been carried out, for the first time, in 26Mg as well as in the neighboring isotopes and the agreement with the experimental level energies is rather remarkable. [ABSTRACT FROM AUTHOR]