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The effect of ytterbium oxide (174Yb2O3) deposition in modifying the material s and electrical properties of mechanically rolled tantalum (MRTa) thin foil is investigated through electron microscopic, crystallographic, elemental analysis, and current-voltage (I–V) characteristics. A 0.82 μm thick layer of 174Yb2O3 over ∼2.1 μm thick MRTa foil (Yb2O3/Ta) reduces the dimension of surface features, and indicates formation of nanoparticles. The electron beam imaging, energy dispersive X-ray (EDX), and X-ray diffraction (XRD) analysis reveal formation of uniformly distributed Yb2O3 on MRTa surface and chemical inertness of the newly formed Yb2O3/MRTa thin film towards oxidation. The room temperature I–V characteristics of both the MRTa foil and Yb2O3/MRTa thin film tested with silver (Ag) top contact electrodes exhibit ohmic conductions and demonstrate an overall enhancement of 92.1% in electrical conductivity after Yb2O3 thin film deposition on MRTa foil.

Lifetime measurements of the lower excited states in the yrast band of $^{167}\mathrm{Lu}$ have been measured using the recoil distance Doppler shift method. The excited nuclear states in $^{167}\mathrm{Lu}$ were populated via $^{159}\mathrm{Tb}\phantom{\rule{4pt}{0ex}}(^{12}\mathrm{C},4n)$ fusion-evaporation reaction at a beam energy of 74 MeV. In the experiment, the lifetime of states from ${13/2}^{\ensuremath{-}}\ensuremath{\hbar}$ to ${29/2}^{\ensuremath{-}}\ensuremath{\hbar}$ spins were obtained. From extracted lifetimes, the reduced transition probabilities $[B(E2)]$ and transition quadrupole moments $({Q}_{t})$ values have been deduced. The large $({Q}_{t})$ values obtained in the experiment indicate high deformation for $^{167}\mathrm{Lu}$ near ground state, a typical characteristic of the mass region. The almost constant values of experimental $B(E2)$ reflects the stability of deformed structure of $^{167}\mathrm{Lu}$ nucleus in the yrast configuration. The experimental results are compared with the results of the cranked Hartree-Fock-Bogoliubov model based total Routhian surface (TRS) calculations. The experimental values are in better agreement with the TRS calculations at low frequencies than at high frequencies.

The multiplicities of $\ensuremath{\alpha}$ particles and neutrons have been measured simultaneously for the reaction $^{16}\mathrm{O}+^{196}\mathrm{Pt}$ forming $^{212}\mathrm{Rn}$ compound nucleus at excitation energies of 56 MeV, 61 MeV, and 68 MeV. Neutrons and $\ensuremath{\alpha}$ particles were detected at various angles in coincidence with the fission fragments. To extract the contribution of pre- and postmultiplicities using the total $\ensuremath{\alpha}$-particle and neutron spectra, moving source formalism was implemented. In the case of $\ensuremath{\alpha}$ particle, near scission contribution has also been extracted. Study of the fission mechanism using light particle emissions are helpful in understanding the detailed fusion-fission reaction dynamics. The statistical model code joanne2, which includes deformation-dependent particle transmission coefficients, binding energies and level densities, has been used to reproduce the measured multiplicities of neutrons and $\ensuremath{\alpha}$ particles by varying the transient (${\ensuremath{\tau}}_{tr}$) and saddle to scission (${\ensuremath{\tau}}_{ssc}$) times. It is found that the fission time scales of the order of $50--70\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}21}$ sec are required to reproduce the neutron and $\ensuremath{\alpha}$-particles multiplicities simultaneously. The fission time scales are the measure of the nuclear viscosity, which is responsible for the dynamic hindrance of the fission process.

The quality of target foils often plays an important role in the success of nuclear physics experiments. Specially, in an experiment intended to measure the level lifetimes of short lived excited nuclear states with Doppler shift attenuation method (DSAM), an isotopically enriched thin target on appropriately thick backing foil of high-Z material is preferentially required. In the present work, a thin (thickness ≈ 0.9 mg/cm2) mono-isotopic Nb target on thick (thickness ≈ 9.2 mg/cm2) lead backing has been prepared using rolling technique at the Inter University Accelerator Center (IUAC), New Delhi. To meet the important criteria of sufficient thickness and proper sticking of two foils without any air gap in-between, some novel methods like heating of stainless steel (SS) pack before rolling, frequent change of rolling pack, use of alcohol during rolling, unidirectional rolling under low pressure specially for rolling lead foil and the composite target, were adopted. The quality check of prepared target foil was done with the energy dispersive X-ray fluorescence (EDXRF) technique. The prepared target has been successfully used in a recent DSAM lifetime measurement experiment at IUAC, New Delhi.

Measuring nuclear level lifetimes of pico-seconds and femto-seconds order is important for understanding typical nuclear shapes. To extract such short lifetimes, specially designed thin targets are needed. A thin isotopically enriched 128Te target of thickness ∼ 1.2 mg/cm2 on the thick backing foil of natural gold of thickness ∼ 9.8 mg/cm2 has been prepared for the Doppler shift attenuation method (DSAM) lifetime measurement. The target was made by vacuum deposition technique using the cryogenic pump based Ultra High Vacuum (UHV) chamber available at the Inter University Accelerator Centre (IUAC), New Delhi. In this activity, a specially designed indigenously developed graphite crucible with 1 mm opening was used to minimize material loss and to improve the deposition efficiency of the material. To get the desired thickness of the target, only 20 mg of isotopically enriched 128Te material was used. The quality check of the prepared foil was done by the Energy Dispersive X-ray fluorescence (EDXRF) technique.

The conventional rolling method fails to yield good quality thin foils of thicknesses less than ~ 2 mg/cm2 for high density materials with Z ≥ 70 (e.g. gold, lead). A special and improved technique has been developed to obtain such low thickness good quality gold foils by rolling method. Using this technique thin gold foils of thickness in the range of 0.850−2.5 mg/cm2 were obtained in the present work. By making use of alcohol during rolling, foils of thickness ~ 1 mg/cm2 can be obtained in shorter time with less effort.

Making multiple thin targets by the evaporation method, without breaking the vacuum of the chamber minimizes the time and the amount of the enriched target material. In the present work the making of two thin isotopic 174Yb2O3 targets: one of thickness ~763 μg/cm2 on a tantalum backing foil (thickness ~3.25 mg/cm2) and the other of ~125 μg/cm2 on carbon backing foil (thickness ~25 μg/cm2) are reported. The targets were made by the evaporation method using a cryogenic pump based Ultra High Vacuum (UHV) chamber available at the Inter University accelerator center (IUAC), Delhi. In this activity only 49 mg of 99.9% enriched 174Yb2O3 target material has been used.

Nuclear level lifetimes of high spin states in yrast and non-yrast bands of 188Pt nucleus have been measured using recoil distance plunger setup present at IUAC, Delhi. In the experiment nuclear states of interest were populated via 174Yb(18O,4n)188Pt reaction at a beam energy of 79MeV provided by 15 UD Pelletron accelerator. The extracted $B(E2\downarrow)$ values show an initial rise up to $4^{+}$ state and then a nearly constant behavior with spin along yrast band, indicating change of nuclear structure in 188Pt at low spins. The good agreement between experimental and TPSM model $B(E2\downarrow)$ values up to $ 4^+$ state suggests an increase in axial deformation of the nucleus. The average absolute $\beta_{2} = 0.20 (3)$ obtained from measured $B(E2\downarrow)$ values matches well the values predicted by CHFB and IBM calculations for oblate ( $ \beta_{2} \sim -0.19$ ) and prolate ( $\beta_{2} \sim 0.22$ ) shapes. As the lifetime measurements do not yield the sign of $ \beta_{2}$ , no definite conclusion can be drawn on the prolate or oblate collectivity of 188Pt on the basis of present measurements.

A thin isotopic 94Zr target of thickness 520μg/cm2 has been prepared for recoil distance Doppler shift method (RDM) lifetime measurement by using an electron beam deposition method on tantalum backing of 3.5 mg/cm2 thickness at Inter University Accelerator Center (IUAC), New Delhi. To meet the special requirement of smoothness of surface for RDM lifetime measurement and also to protect the outer layer of 94Zr from peeling off, a very thin layer of gold has been evaporated on a 94Zr target on a specially designed substrate holder. In all, 143 mg of 99.6% enriched 94Zr target material was utilized for the fabrication of 94Zr targets. The target has been successfully used in a recent RDM lifetime measurement experiment at IUAC.

Lifetimes of excited states in the yrast band of the gamma-soft nuclei 131Ce and 133Pr have been measured using the recoil distance Doppler shift and Doppler shift attenuation methods. The yrast bands in 131Ce and 133Pr are based on odd decoupled neutron νh 11/2 high Ω and proton π h 11/2 low Ω orbitals, respectively. The triaxiality parameter extracted from the experimentally deduced values of transition quadrupole moments, within the framework of cranked Hartree–Fock–Bogoliubov (CHFB) and total Routhian surface (TRS) calculatons, is γ ∼ −80∘ for the band in 131Ce at high spins, while for the band in 133Pr, the value of γ is close to 0∘. This agrees well with the γ shape polarization property of high and low Ωh 11/2 orbitals in these gamma-soft nuclei.

The emergence and evolution of collective excitations in complex nuclei remains a central problem in the quest to understand the nuclear many-body problem. Nuclear quadrupole collectivity is usually investigated via electric quadrupole observables. Here, however, we measure the $g$ factors of low-excitation states in $^{111}\mathrm{Cd}$ and $^{113}\mathrm{Cd}$ and show that they are sensitive to the nature of the collectivity in these nuclei in ways that the electric quadrupole observables are not. The particle-vibration model, which assumes spherical core excitations, cannot explain the $g$ factors, whereas a particle-rotor model with a small, nonzero core deformation does. The contrast of the two models is made stark by the fact that they begin from the same limiting $g$-factor values: It is shown that when an odd nucleon occupies a spherical orbit with angular momentum $j=1/2$, or a deformed orbit with $j=1/2$ parentage, the particle-vibration model and the particle-rotor model both reduce to the same $g$-factor value in their respective limits of zero particle-vibration coupling or zero deformation.

Lifetimes of the high spin states of 179Re have been measured by the recoil distance technique. The high spin states in 179Re were populated by the fusion evaporation reaction 165Ho(18O, 4n)179Re at a beam energy of 82 MeV. The deformation obtained from these measurements for the h92 configuration (β2 ∼ 0.25) is found to be ∼ 14% higher than the deformation for the d52 configuration (β2 ∼ 0.22). This higher deformation for the h92 configuration compared to the d52 configuration, confirms its deformation driving nature. Calculations using the cranked Hartree - Fock - Bogoliubov are done for the two configurations and they provide a qualitative description of the experimental observations.

The K α 1 , K α 2 , K β 1 , K β 2 , and the Ll, L α , L β and L γ X-ray production (XRP) cross sections and the relative intensity ratios for seven rare-earth elements with 60⩽ Z ⩽70 have been measured for 20, 22 and 25 MeV proton impact. The experimental data on the L-shell XRP cross sections for high energy proton impact have been reported for the first time. The measured XRP cross sections for all the K-lines and the relative intensity ratios K α 1 /K α , K α 2 /K α , K β 1 /K α , K β 2 /K α and K β /K α are in good agreement with the theoretical ones calculated using ECPSSR ionisation cross sections for all the elements investigated at the three beam energies. The Ll, L α , L β , and L γ XRP cross sections measured at the three proton energies are found to be in general higher than the theoretical values calculated using the ECPSSR ionisation cross sections and the RDHS model-based L i sub-shell fluorescence and Coster–Kronig (CK) yields. The measured relative intensity ratios L β /L α , and L γ /L α exhibit good agreement with the theoretical ones for all the elements under investigation, whereas the Ll/L α ratios are found to deviate from the theoretical ones.

The transient-field technique has been used in both conventional kinematics and inverse kinematics to measure the $g$ factors of the 2${}_{1}^{+}$ states in the stable even isotopes of Ru, Pd, and Cd. The statistical precision of the $g({2}_{1}^{+})$ values has been significantly improved, allowing a critical comparison with the tidal-wave version of the cranking model recently proposed for transitional nuclei in this region.

We report on the g factor measurement of the isomeric 7 − state ( E * = 2219 keV , T 1 / 2 = 5.9 ( 8 ) μs ) in the neutron-rich 126Sn nucleus. The nucleus was produced by the fission of a relativistic 238U beam and reaction products were selected by the FRS fragment separator at GSI. For the first time, spin-alignment was observed after relativistic fission. It was used to deduce the g factor of the 7 − isomeric state, g ( 7 − ) = − 0.098 ( 9 ) , from the measured perturbed angular distribution of its γ decay using the RISING Cluster detectors. The observed value confirms the suggested ν ( h 11 / 2 − 1 d 3 / 2 − 1 ) dominant configuration, which has been proposed for the 7 − isomers in neutron-rich Sn isotopes. The failure of the g factor additivity rule and the importance of core polarization evolution with increasing distance from the doubly-magic 132Sn is discussed. The first observation of 18(8)% of spin-alignment produced by the relativistic fission of a 238U beam paves the way to study moments of neutron-rich (sub-)microsecond isomers, which are difficult to align by other means.

The feasibility of measuring g -factors using the TDPAD method applied to high-energy, heavy fragmentation products is explored. The 2623keV $\ensuremath I^{\pi}=12^+$ isomer in 192Pb with $ \tau$ = 1.57 μs has been produced using the fragmentation of a 1A GeV 238U beam. The results presented demonstrate for the first time that such heavy nuclei produced in a fragmentation reaction with a relativistic beam are sufficiently well spin-aligned. Moreover, the rather large value of the alignment, 28(10)% of the maximum possible, is preserved during the separation process allowing the determination of magnetic moments. The measured values of the lifetime, $ \tau$ = 1.54(9) μs, and the g -factor, g = - 0.175(20) , agree with the results of previous investigations using fusion-evaporation reactions.

The g factors of the 2{sub 1}{sup +} states in {sup 54}Fe and {sup 58}Fe have been measured relative to the 2{sub 1}{sup +} state g factor of {sup 56}Fe using the transient-field technique in inverse kinematics. The results are in satisfactory agreement with recent shell model calculations in the fp model space. For {sup 56}Fe and {sup 58}Fe the g factors approach Z/A and are therefore also consistent with collective interpretations of these 2{sup +} states.

The transient-field technique has been used to measure the $g$ factor of the ${2}_{1}^{+}$ state in $^{56}\mathrm{Fe}$ relative to the independently determined $g$ factor of the first $5/{2}^{\ensuremath{-}}$ state in $^{57}\mathrm{Fe}$. The new result for $^{56}\mathrm{Fe}$ agrees with previous measurements but is more precise. Implications for calibrating the transient field and $g$-factor measurements in the $\mathit{fp}$ region are discussed.

New sub-mu s isomers have been observed in the neutron-rich Sn isotopes. Sn-125,Sn-127,Sn-129 nuclei have been produced in a relativistic fission reaction of U-238 on a Be-9 target at 750 A.MeV and by the fragmentation of Xe-136 at 600 A.MeV populating high-spin yrast states. In addition to the already known mu s isomers, three new ones with sub-mu s half-lives have been observed. These yrast isomers are the high-spin members of the nu(d(3/2)(-1)h(11/2)(-2)) and nu h(11/2)(-n), seniority v = 3 multiplets leading to isomeric (23/2(+)) and (27/2(-)) states, respectively. Added to the already known 19/2(+)mu s isomers in this region the current work completes the systematic information of neutron-hole excitations toward the filling of the last h(11/2) orbital at N = 82. The results are discussed in the framework of state-of-the-art shell-model calculations using realistic interactions.

High spin states in {sup 52}Cr have been populated by means of the reaction {sup 27}Al({sup 28}Si,3p){sup 52}Cr at a beam energy of 70 MeV and studied with an array, consisting of eight Compton-suppressed clover germanium detectors. Eleven new {gamma} rays have been assigned to {sup 52}Cr and placed in the level scheme. The level structure of {sup 52}Cr has been extended up to E{sub x}{approx_equal}10 MeV. Spins and parities have been assigned to many of the levels on the basis of directional correlations and linear polarization measurements. The band structures are discussed in the framework of cranked Woods-Saxon and deformed Hartree-Fock (HF) models. Both the oblate and prolate orbits are considered for J projection in the HF model. The K=0{sup +} band is properly understood if we consider the J projection from both prolate and oblate orbits and collectivity shown by the K=4{sup +} band to be accounted for by taking the J projection from prolate HF configurations. Thus there is prolate and oblate shape coexistence in {sup 52}Cr.

The shape coexistence phenomena in {sup 189}Tl are investigated by measuring the lifetimes of the high spin states through the recoil distance LIFETIME measurement technique. For this study, the {sup 165}Ho({sup 28}Si, 4n){sup 189}Tl reaction at a beam energy of 138 MeV was used. In this measurement, the lifetimes of four levels of the negative parity {pi}h{sub 9/2} band and seven levels of the positive parity {pi}i{sub 13/2} band are found. The extracted transition quadrupole moments for the positive parity {pi}i{sub 13/2} band show interesting changes with increasing level spin. This band starts with a small oblate shape (Q{sub t}=1.1 e b) at low spin (17/2{sup +}) and attains a strongly deformed prolate shape (Q{sub t}=8.8 e b) at high spins (33/2{sup +}). On the other hand, the negative parity {pi}h{sub 9/2} band shows a stable oblate structure against the increasing spin with an average quadrupole moment (Q{sub t}) of {approx}2.6 e b. To better understand the shape coexistence phenomena in {sup 189}Tl nucleus, the experimental results are also compared with the results of the total Routhian surfaces calculations, for the positive parity {pi}i{sub 13/2} and the negative parity {pi}h{sub 9/2} bands in this nucleus. The comparison confirms the shapemore » coexistence structure of the {sup 189}Tl nucleus in the positive parity {pi}i{sub 13/2} configuration.« less

This paper demonstrates the feasibility of quadrupole moment measurements on isomeric levels populated in projectile fragmentation reactions. The neutron-rich $^{61}\mathrm{Fe}$$(9/{2}^{+})$ [${E}^{*}=$ 861 keV, ${T}_{1/2}=$ 239(5) ns] isomer was produced and spin aligned by the intermediate energy fragmentation of a $^{64}\mathrm{Ni}$ beam and implanted in a Cd single crystal. Its spectroscopic quadrupole moment $|{Q}_{s}|=41(6)\phantom{\rule{0.3em}{0ex}}e\phantom{\rule{0.3em}{0ex}}{\mathrm{fm}}^{2}$ agrees with mean-field based calculations using the finite-range Gogny force, suggesting a moderately deformed shape characterized by an intrinsic charge quadrupole moment ${Q}_{0}=\ensuremath{-}85\phantom{\rule{0.3em}{0ex}}e\phantom{\rule{0.3em}{0ex}}{\mathrm{fm}}^{2}$ or ${Q}_{0}=+115\phantom{\rule{0.3em}{0ex}}e\phantom{\rule{0.3em}{0ex}}{\mathrm{fm}}^{2}$. The present measurement paves the way for future determinations of isomeric quadrupole moments in more exotic nuclei.

A controlled and precise determination of the cross sections of the fusion reactions {sup 7}Be(p,{gamma}){sup 8}B and {sup 3}He({sup 4}He,{gamma}){sup 7}Be, which play an important role in determining the solar neutrino flux, necessitates the knowledge of a precise value of the electron-capture half-life of {sup 7}Be. This half-life may depend on the material hosting the {sup 7}Be atoms via small modifications of the electron density around the {sup 7}Be nucleus. In this brief communication we report on the measurement of {sup 7}Be implanted in four materials: copper, aluminum, sapphire, and PVC. The four results are consistent with a null host dependence within two standard deviations and their weighted average of 53.236(39) d agrees very well with the adopted value in the literature, 53.22(6) d. The present results may exhibit a slight (0.22%) increase of the half-life at room temperature for metals compared to insulators that requires further studies.

The g -factor of the 19 / 2 + T 1 / 2 = 4.5 ( 3 ) μ s isomer in 127Sn, which was populated in relativistic projectile fragmentation, was measured within the g-RISING campaign at GSI, utilizing the time-differential perturbed angular distribution method. The deduced g -factor | g | ≈ 0.16 is in agreement with theoretical estimates based on the empirical g -factors.

Jolie, J. Ilie, G. Reiter, P. Richard, A. Scherillo, A. Striepling, T. Warr, N. Banu, A. Becker, F. Bednarczyk, P. Doornenbal, P. Gerl, J. Grawe, H. Gorska, M. Kojouharov, I. Mandal, S. Saito, N. Saito, T. R. Wollersheim, H. -J. Mallion, S. Neyens, G. Turzo, K. Van Duppen, P. Vermeulen, N. Podolyak, Zs. Gelletly, W. Regan, P. H. Walker, P. M. Catford, W. N. Liu, Z. Williams, S. Blazhev, A. Lozeva, R. Detistov, P. Atanasova, L. Damyanova, G. Gil, D. Cortina Benlliure, J. Kurtukian Nieto, T. Caserejos, E. Daugas, J. M. Belier, G. Meot, V. Roig, O. Simpson, G. Tsekhanovich, I. S. Matea, I. Schwengner, R. Hass, M. Singh, B. S. Nara Chamoli, S. K. Goldring, G. Regev, I. Vaintraub, S. Balabanski, D. L. Lo Bianco, G. Gladnishki, K. Saltarelli, A. Petrache, C. Benzoni, G. Blasi, N. Bracco, A. Camera, F. Million, B. Leoni, S. Wieland, O. Maj, A. Kmiecik, M. Grebosz, J. Bednarczyk, P. Styczen, J. Lach, M. Meczynski, W. Mazurek, K. Pfutzner, M. Korgul, A. Ionescu-Bujor, M. Iordachescu, A. Zamfir, V. Jungclaus, A. Georgiev, G. Cullen, D. M. Freeman, S. J. Smith, A. G. Orlandi, R. Clark, R. M. Bentley, M. A. Hammond, G. Wadsworth, R. Buerger, A. Huebel, H. Rudolph, D. Fahlander, C. Simpson, J. Herzberg, R. D. Page, R. D. Nolan, P. Davidson, T. Woods, P. Bruce, A. M. Faestermann, T. Kruecken, R. Mach, H. Rubio, B. Algora, A.

High-spin states in $^{122}\mathrm{Cs}$ have been studied via $^{107}\mathrm{Ag}$($^{19}\mathrm{F}$, p3n)$^{122}\mathrm{Cs}$ fusion evaporation reaction at beam energy of 93 MeV. Fifteen new transitions belonging to $^{122}\mathrm{Cs}$ have been observed and placed in the level scheme. The level structure of $^{122}\mathrm{Cs}$ has been extended up to ${E}_{x}\ensuremath{\approx}7$ MeV and $J\ensuremath{\approx}28\ensuremath{\hbar}$. We have performed the linear polarization measurements using the Clover detectors to assign the unknown spins and parities of a few bands. We have also observed a few linking transitions between negative and positive parity bands indicating the octupole collectivity in this nucleus. The structure of the various bands are discussed in the frame work of the cranked Hartree-Fock-Bogoliubov model and the microscopic projected Hartree-Fock model calculations.

The lifetime measurements are done for different quasiparticle bands in neutron-deficient $^{187}\mathrm{Tl}$ nucleus through the recoil distance Doppler shift technique. A sudden change in the transition quadrupole moment is observed for both positive and negative parity prolate bands as one moves from lower spins to higher spins, indicating a major shape transitions in this nucleus. The prolate-oblate shape coexistence picture of this nucleus is discussed in the light of the extracted transition quadrupole moments. For the negative parity $\ensuremath{\pi}{h}_{9/2}$ band the transition quadrupole moment for the low K (3/2) prolate sequence is found to be higher than that of the high K (9/2) oblate sequence. The total Routhian surface calculations are done within the framework of the cranked Hartree-Fock-Bogoliubov model to analyze the shape coexistence picture theoretically. The theoretical predictions are found to be in close agreement with the experimental observations. The existence of a superdeformed band is also predicted for the nucleus.

The nucleus of ${}^{173}\mathrm{Ta}$ was populated using the reaction ${}^{159}\mathrm{Tb}{(}^{18}\mathrm{O}{,4n)}^{173}\mathrm{Ta}$ at a beam energy of 84 MeV. Lifetime measurements in the bands built on two Nilsson configurations $\ensuremath{\pi}{h}_{9/2}[541]{1/2}^{\ensuremath{-}}$ and $\ensuremath{\pi}{g}_{7/2}[404]{7/2}^{+}$ were performed using the recoil-distance Doppler shift method. The measured lifetimes were used to extract the reduced transition probabilities $B(E2).$ Microscopic Hartree-Fock theory with the angular momentum projection was used for calculating the reduced transition probabilities. The ${Q}_{t}$ values obtained from the measured $B(E2)$ values show a larger collectivity for the ${h}_{9/2}$ band as compared to the ${g}_{7/2}$ band. Cranked Hartree-Fock Bogoliubov calculations were used for calculating the quasiparticle Routhians. The experimental results in conjunction with the cranking calculations also explain the experimental band-crossing delays associated with the ${i}_{13/2}$ neutron alignment in the ${}^{173}\mathrm{Ta}$ nucleus.

We report on g-factor measurements of the 19/2+ T1/2=4.5(3) μs isomer in 127Sn and the 10+ T1/2=2.69(23) μs isomer in 128Sn. These isomers were produced and spin-aligned in relativistic heavy-ion fragmentation at GSI and were selected and separated by the GSI fragment separator (FRS). The γ-rays of the isomeric decay were detected by the RISING γ-ray spectrometer. The method of time-differential perturbed angular distributions was utilized. The measured g-factors, g(19/2+; 127Sn)=− 0.17(2) and g(10+; 128Sn)=− 0.20(4), are compared with shell model calculations. The measured g-factors confirm the predominantly νh11/2− 2 and ν(s1/2− 1h11/2−2) character of the 10+ and 19/2− isomers in 128Sn and 127Sn, respectively. The results demonstrate the feasibility of the method for similar measurements in exotic neutron-rich nuclei.

Pre- and post-scission α-particle multiplicities have been measured for the reaction 16O + 194Pt at 98.4 MeV forming compound nucleus 210Rn. The α-particle’s yield has been measured in coincidence with the fission fragments at various angles. The moving source analysis was performed to extract the alpha particle multiplicity which yielded the contribution of pre- and post- scission components. The pre-scission α-particle multiplicity has been compared with JOANNE2 statistical model code predictions to extract fission time scale and which is observed to be around 55zs (1zs=10−21s).Pre- and post-scission α-particle multiplicities have been measured for the reaction 16O + 194Pt at 98.4 MeV forming compound nucleus 210Rn. The α-particle’s yield has been measured in coincidence with the fission fragments at various angles. The moving source analysis was performed to extract the alpha particle multiplicity which yielded the contribution of pre- and post- scission components. The pre-scission α-particle multiplicity has been compared with JOANNE2 statistical model code predictions to extract fission time scale and which is observed to be around 55zs (1zs=10−21s).