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In this paper, we investigated every potential scenario for selenium-induced heavy ion fusion reactions using astatine isotopes as the target. In this context, we examined 74,76−80,82Se projectiles and 209−211At targets having longer half-lives of comprising 21 fusion reactions for the synthesis of superheavy element Z=119. We assessed fusion cross-sections (σfus), compound nucleus formation probability (PCN), and survival probability (Psur) for 74,76−80,82Se projectiles on 209−211At targets. The evaporation residue cross-sections (σER) is found to be larger for the fusion reaction of 82Se+210At of about 14.1fb. Hence, these striking results are useful in the synthesis of superheavy element Z=119. [ABSTRACT FROM AUTHOR]

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Lifetimes of excited states in 116 Xe were measured using the recoil-distance Doppler-shift technique. Excited 116 Xe nuclei were populated in the fusion-evaporation reaction 102 Pd( 16 O,2n) 116 Xe. Lifetimes of the 2 1 + and 4 1 + states were evaluated using the differential decay-curve method with γ - γ -coincidence data as well as lifetimes of the 6 1 + and 7 1 - states using simulations of spectra considering Doppler-shift attenuation effects. [ABSTRACT FROM AUTHOR]

The atomic masses of isotopes of elements beyond fermium, which can presently only be produced online via fusion-evaporation reactions, have until recently been determined only from α decay chains reaching nuclides with known atomic masses. Especially in the case of lower-yield nuclides, for which the sufficiently detailed nuclear spectroscopy required to fully determine the nuclear structure is not possible, such indirect mass determinations may suffer systematic errors. For many superheavy nuclides, their decay chains end in spontaneous fission or in β -decay prior to reaching nuclides of known mass. To address this dearth of accurate atomic masses, we have developed a multi-reflection time-of-flight mass spectrograph that can make use of decay-correlations to accurately and precisely determine atomic masses for the very low-yield superheavy nuclides. [ABSTRACT FROM AUTHOR]

High-spin nuclear isomers in N ≈ Z nuclei between doubly magic 40 Ca and 56 Ni provide an excellent testing ground for the nuclear shell model and questions related to isospin symmetry breaking in the vicinity of the proton drip line. The purpose of the present study is to investigate the possibility of weak electromagnetic decay branches along the decay paths of the 6526-keV 10 + isomer in 54 Fe. The isomer was strongly populated by means of the fusion-evaporation reaction 24 Mg( 36 Ar, α 2 p ) 54 m Fe. The Gammasphere array was used to detect γ -ray cascades emitted from the isomeric state. By means of γ γ γ coincidences, weak non-yrast decay branches can be discriminated, with the isomer's half-life confirmed at T 1 / 2 = 363 (4) ns. The yrast 6 1 + → 2 1 +   E 4 cross-over transition was interrogated. The observations are compared with shell-model calculations. [ABSTRACT FROM AUTHOR]

The radiation detection resonance ionization spectroscopy (RADRIS) technique enables laser spectroscopic investigations of the heaviest elements which are produced in atom-at-a-time quantities from fusion-evaporation reactions. To achieve a high efficiency, laser spectroscopy is performed in a buffer-gas environment used to thermalize and stop the high-energy evaporation residues behind the velocity filter SHIP. The required cyclic measurement procedure in combination with the applied filament collection for neutralization as well as confinement of the stopped ions and subsequent pulse-heat desorption constrains the applicability of the technique. Here, some of these limitations and also opportunities that arise from this unique measurement setup will be evaluated. [ABSTRACT FROM AUTHOR]

The only experimentally proved method of synthesis of superheavy elements (SHE) is the use of fusion reactions with heavy ions. Modeling of complicated dynamics of nuclear reactions induced by heavy ions is done within a multidimensional dynamical model of nucleus-nucleus collisions based on the Langevin equations. The model gives a continuous description of the system evolution starting from the well-separated target and projectile in the entrance channel of the reaction up to the formation of final reaction products. In this paper, we study fusion dynamics in competition with dominating channels of quasifission and deep inelastic transfer. The estimates have been made for cross sections for synthesis of new neutron-enriched isotopes of known SHE in -evaporation channels as well as fusion cross section for reactions with Ti and Cr ions leading to yet unknown SHE with and 120. [ABSTRACT FROM AUTHOR]

Nuclear-structure studies using fusion reactions are reviewed in terms of prospects for advancement using the next generation of γ -ray tracking arrays such as AGATA. Properties discussed include those of light N = Z nuclei and rotational behaviour in heavy nuclei at high values of angular momentum and internal excitation energy. [ABSTRACT FROM AUTHOR]

This article is a new edition of the review published six years ago by the same auhors [Eur. Phys. J. A 54, (2017) 218]. It includes additionally the most recent and significant results obtained in the field of heavy-ion fusion near and below the Coulomb barrier, which have been important for the advance of our knowledge. In particular, we present a selection of recent findings concerning the fusion dynamics of light systems, which is relevant for astrophysics, and moreover recent information obtained from measurements involving heavy-ion exotic beams. With respect to the previous paper, the description of relevant set-ups and methods is done in a dedicated Section. Recent advances obtained in the field of near and sub-barrier heavy-ion fusion reactions are reported. Early data on sub-barrier fusion taught us that cross sections strongly depend on the low-energy collective modes of the colliding nuclei, and on couplings to transfer channels. The coupled-channels model has been successful in the interpretation of the experiments, and fusion barrier distributions may yield the fingerprint of the relevant coupled channels. Far below the barrier, the slope of the excitation function keeps increasing in many cases and standard calculations over-predict the cross sections. This was named a hindrance phenomenon whose physical origin is a matter of debate. Recent theoretical developments suggest that hindrance may be a consequence of the Pauli exclusion principle. Hindrance has far-reaching consequences in astrophysics where the fusion of light systems determines stellar evolution during the carbon and oxygen burning stages. [ABSTRACT FROM AUTHOR]

High-spin states of 77Kr are studied via the fusion-evaporation reaction 68Zn(16O, 2p5n)77Kr with the beam energy of 80 MeV provided by the Tandem accelerator at Japan Atomic Energy Agency (JAEA). The intensity of the beam is I x 1 pnA. In the present work, some new transitions are found to constitute the new band of the proposed level scheme. It is very similar to the M1 transition from the level energy, so it is proposed that this band is the M1 band. [ABSTRACT FROM AUTHOR]

We have developed a novel ion source and beam diagnostic system for the production and detection of radioactive francium (Fr) isotopes. The Fr ions are produced using a fusion–evaporation reaction at the RIKEN Nishina Center, Japan. The installation of an infrared heater has enabled a precise and rapid control of the target temperature, and the newly developed diagnostic system allows for a quantitative characterization of the extracted ion beam. With the new system, an analysis of the F r 208 − 211 isotopes has been performed. Additionally, the flux of F r 210 ions has been estimated as 6.7 × 106 s−1 corresponding to an extraction efficiency of 24.5% and a beam purity of 1.6 × 10−5. [ABSTRACT FROM AUTHOR]

Quasifission barriers were studied in the superheavy region 1 0 4 ≤ Z ≤ 1 2 6 using different projectile-target combinations. The different entrance channels parameters on quasifission barriers give an insight into the formation of compound nuclei and quasifission process. The quasifission barriers are more systematic for χ m = 0. 2 5 χ CN + 0. 7 5 χ eff . The effect of compound nucleus fissility χ CN and effective entrance channel fissility χ eff on quasifission barriers were investigated. The quasifission barriers are strongly influenced by χ CN and χ eff entrance channel parameters. The detailed investigations of entrance channel parameters on quasifission barriers provide a thorough understanding of compound nuclei formation in the superheavy element in the region 1 0 4 ≤ Z ≤ 1 2 6. Eventually, this study helps in the selection of projectile-target combinations to synthesis of superheavy nuclei. [ABSTRACT FROM AUTHOR]

The device of a vortex plasma thruster is proposed, in which the collective accelerator mechanism of nuclear fusion reaction is used. It is shown that in the approximation of three nuclei, the threshold value of the potential energy spent on overcoming the Coulomb barrier is several orders of magnitude less than the threshold value of the kinetic energy of paired collisions of nuclei. This paper also presents a generator of electrical energy and a generator of artificial ball lightning, which use the phenomenon of induction of cold fusion in a supersonic plasma vortex. [ABSTRACT FROM AUTHOR]

The TULIP project aims to produce radioactive ion beams of short-lived neutron-deficient isotopes by using fusion-evaporation reactions in an optimized Target Ion Source System (TISS). The first step consisted of the design of a TISS to produce rubidium isotopes. It was tested with a primary beam of 22Ne@4.5 MeV/A irradiating a natural Ni target at the SPIRAL1/GANIL facility in March 2022. Rates of 76 , 78 Rb were measured as well as an exceptionally short atom-to-ion transformation time for an ISOL system, of the order of 200 μ s. The second step of the project aims at producing neutron-deficient short-lived metallic isotopes in the region of 100Sn. A "cold" prototype has been realized to study the electron impact ionization in the TISS cavity and a "hot" version is under construction to prepare an on-line experiment expected in the near future. [ABSTRACT FROM AUTHOR]

The quantum tunneling and emission of a single constituent nucleon provide a beautifully simple and unique window into the complex properties of atomic nuclei at the extreme edge of nuclear existence. In particular, for odd-odd proton emitting nuclides, the associated decay energy and partial half-life can be used to probe the correlations between the valence neutrons and protons which have been theoretically predicted to favour a new type of nuclear superfluidity, isoscalar neutron-proton pairing, for which the experimental "smoking gun" remains elusive. In the present work, proton emission from the lanthanum isotope 57 116 La59, 23 neutrons away from the only stable isotope 57 139 La82, is reported. 116La nuclei were synthesised in the fusion-evaporation reaction 58Ni(64Zn, p5n)116La and identified via their proton radioactivity using the mass spectrometer MARA (Mass Analysing Recoil Apparatus) and the silicon detectors placed at its focal plane. Comparisons of the measured proton energy (Ep = 718 ± 9 keV) and half-life (T1/2 = 50 ± 22 ms) with values calculated using the Universal Decay Law approach indicate that the proton is emitted with an orbital angular momentum l = 2 and that its emission probability is enhanced relative to its closest, less exotic, odd-even lanthanum isotope ( 57 117 La60) while the proton-emission Q-value is lower. We propose this to be a possible signature for the presence of strong neutron-proton pair correlations in this exotic, neutron deficient system. The observations of γ decays from isomeric states in 116La and 117La are also reported. Neutron-proton pairing is a topic of continuous interest in nuclear physics and open questions remain. The authors experimentally observe direct proton decay from the ground state of odd-odd 116La, providing support for the presence of strong neutron-proton pair correlations in this exotic, neutron deficient system. [ABSTRACT FROM AUTHOR]

The quantum tunneling and emission of a single constituent nucleon provide a beautifully simple and unique window into the complex properties of atomic nuclei at the extreme edge of nuclear existence. In particular, for odd-odd proton emitting nuclides, the associated decay energy and partial half-life can be used to probe the correlations between the valence neutrons and protons which have been theoretically predicted to favour a new type of nuclear superfluidity, isoscalar neutron-proton pairing, for which the experimental "smoking gun" remains elusive. In the present work, proton emission from the lanthanum isotope 57 116 La59, 23 neutrons away from the only stable isotope 57 139 La82, is reported. 116La nuclei were synthesised in the fusion-evaporation reaction 58Ni(64Zn, p5n)116La and identified via their proton radioactivity using the mass spectrometer MARA (Mass Analysing Recoil Apparatus) and the silicon detectors placed at its focal plane. Comparisons of the measured proton energy (Ep = 718 ± 9 keV) and half-life (T1/2 = 50 ± 22 ms) with values calculated using the Universal Decay Law approach indicate that the proton is emitted with an orbital angular momentum l = 2 and that its emission probability is enhanced relative to its closest, less exotic, odd-even lanthanum isotope ( 57 117 La60) while the proton-emission Q-value is lower. We propose this to be a possible signature for the presence of strong neutron-proton pair correlations in this exotic, neutron deficient system. The observations of γ decays from isomeric states in 116La and 117La are also reported. Neutron-proton pairing is a topic of continuous interest in nuclear physics and open questions remain. The authors experimentally observe direct proton decay from the ground state of odd-odd 116La, providing support for the presence of strong neutron-proton pair correlations in this exotic, neutron deficient system. [ABSTRACT FROM AUTHOR]

Excited states of 117Sn have been populated using the fusion-evaporation reaction 114Cd(7Li, 1p3n) at a beam energy of 48 MeV. A total of nine new transitions have been identified and added into the level scheme of 117Sn. Based on the systematical comparisons with the neighboring Sn isotopes and the configuration-fixed constrained triaxial relativistic mean-field (RMF) calculations, a collective structure and two isomers are proposed to exist in 117Sn. The phenomenon of shape coexistence has been extended to A = 117 in odd-A Sn isotopes for the first time. [ABSTRACT FROM AUTHOR]

The heaviest actinide elements are only accessible in accelerator-based experiments on a one-atom-at-a-time level. Usually, fusion–evaporation reactions are applied to reach these elements. However, access to the neutron-rich isotopes is limited. An alternative reaction mechanism to fusion–evaporation is multinucleon transfer, which features higher cross-sections. The main drawback of this technique is the wide angular distribution of the transfer products, which makes it challenging to catch and prepare them for precision measurements. To overcome this obstacle, we are building the NEXT experiment: a solenoid magnet is used to separate the different transfer products and to focus those of interest into a gas-catcher, where they are slowed down. From the gas-catcher, the ions are transferred and bunched by a stacked-ring ion guide into a multi-reflection time-of-flight mass spectrometer (MR-ToF MS). The MR-ToF MS provides isobaric separation and allows for precision mass measurements. In this article, we will give an overview of the NEXT experiment and its perspectives for future actinide research. [ABSTRACT FROM AUTHOR]

RAdiation-Detected Resonance Ionization Spectroscopy (RADRIS) is a versatile method for highly sensitive laser spectroscopy studies of the heaviest actinides. Most of these nuclides need to be produced at accelerator facilities in fusion-evaporation reactions and are studied immediately after their production and separation from the primary beam due to their short half-lives and low production rates of only a few atoms per second or less. Only recently, the first laser spectroscopic investigation of nobelium ( Z = 102 ) was performed by applying the RADRIS technique in a buffer-gas-filled stopping cell at the GSI in Darmstadt, Germany. To expand this technique to other nobelium isotopes and for the search for atomic levels in the heaviest actinide element, lawrencium ( Z = 103 ), the sensitivity of the RADRIS setup needed to be further improved. Therefore, a new movable double-detector setup was developed, which enhances the overall efficiency by approximately 65% compared to the previously used single-detector setup. Further development work was performed to enable the study of longer-lived (t 1 / 2 > 1 h) and shorter-lived nuclides (t 1 / 2 < 1 s) with the RADRIS method. With a new rotatable multi-detector design, the long-lived isotope 254 Fm (t 1 / 2 = 3.2   h ) becomes within reach for laser spectroscopy. Upcoming experiments will also tackle the short-lived isotope 251 No (t 1 / 2 = 0.8   s ) by applying a newly implemented short RADRIS measurement cycle. [ABSTRACT FROM AUTHOR]

The γ decay of the elusive narrow, near-threshold proton resonance in 11B was investigated at Laboratori Nazionali di Legnaro (INFN) in a particle- γ coincidence experiment, using the 6Li(6Li,p γ) fusion-evaporation reaction and the GALILEO-GALTRACE setup. No clear signature was found for a possible E1 decay to the 1/2 1 − , first-excited state of 11B, predicted by the Shell Model Embedded in the Continuum (SMEC) with a branching of 0.98 − 69 + 167 × 10 − 3 with respect to the dominant particle-decaying modes. The statistical analysis of the γ -ray spectrum provided an average upper limit of 2.37 × 10 − 3 for this γ -ray branching, with a global significance of 5 σ. On the other hand, by imposing a global confidence level of 3 σ , a significant excess of counts was observed for E = γ 9300 (20) keV, corresponding to a resonance energy of 11429(20) keV (namely 200(20) keV above the proton separation energy of 11B) and a γ -ray branching of 1.12 (35) × 10 − 3. This result is compatible with the SMEC calculations, potentially supporting the existence of a near-threshold proton resonance in 11B. [ABSTRACT FROM AUTHOR]

The rare-earth region has been the focus of various studies aiming at the understanding of nuclear structure and providing information on the details of the reaction mechanism. The Gd isotopes belong to this group of nuclei and despite the available spectroscopic information, several open questions about their structure still exist, such as the inter-band transitions related to shape evolution or branching-ratios in deformed states. In addition, production cross sections of different reactions to Gd isotopes are largely unknown. In this work, we report on an experimental attempt to populate the excited states in the isotopes 152,153,154Gd by employing the heavy-ion fusion reaction 18O+138Ba → 156-xGd + xn in the 58-64 MeV energy range (center-of-mass). The experiment was conducted at the 9 MV FV Pelletron Tandem at the Horia Hulubei National Institute for Physics and Nuclear Engineering, employing the ROSPHERE array. Several branching-ratios for energy levels in 152,153Gd have been measured, offering new and updated values. Furthermore, relative cross sections regarding the fusion-evaporation reactions 138Ba(18O, 4n)152Gd, 138Ba(18O, 3n)153Gd, and 138Ba(18O, 2n)154Gd have been measured and compared with theoretical calculations with PACE4. [ABSTRACT FROM AUTHOR]

In this paper, light charged particle emission in the evaporation residue channel for the 190 MeV 40 Ar + 27 Al reaction leading to 67 Ga composite nuclei at E x = 91 MeV and angular momentum up to 46 ℏ has been re-analyzed. The main goal was to study the decay of 67 Ga on the basis of an extended set of observables in order to provide a description of the evaporative decay cascades using the multistep Monte Carlo approach. The proton and α -particle energy spectra along with their angular distributions and ratios of differential multiplicities have been considered. The measured observables were compared with statistical model calculations. Having used a single-step Monte Carlo approach and standard parameters decades ago, the model does not provide a good description of the full dataset. Only a subset of the data was reproduced by assuming emitting nuclei with very large deformed shapes in a previous work published in the late 1980s. In the reported analysis, better agreement has been observed. Using the new transmission coefficients from the Optical Model, the parameters of which have recently been derived, the multi-step approach and the introduction of a nuclear shape description based on the nuclear stratosphere allowed us to realize a significant improvement. [ABSTRACT FROM AUTHOR]

The new neutron-deficient isotope 249 No was synthesized for the first time in the fusion-evaporation reaction 204 Pb( 48 Ca,3n) 249 No. After separation, using the kinematic separator SHELS, the new isotope was identified with the GABRIELA detection system through genetic correlations with the known daughter and granddaughter nuclei 245 Fm and 241 Cf. The alpha-decay activity of 249 No has an energy of 9129(22) keV and half-life 38.3(2.8) ms. An upper limit of 0.2% was measured for the fission branch of 249 No. Based on the present data and recent information on the decay properties of 253 Rf and aided by Geant4 simulations, the ground state of 249 No is assigned the 5/2 + [622] neutron configuration and a partial decay scheme from 253 Rf to 245 Fm could be established. The production cross-section was found to be σ (3n)=0.47(4) nb at a mid-target beam energy of 225.4 MeV, which corresponds to the maximum of the calculated excitation function. Correlations of the 249 No alpha activity with subsequent alpha decays of energy 7728(20) keV and half-life 1. 2 - 0.4 + 1.0 min provided a firm measurement of the electron-capture or β + branch of 245 Fm to 245 Es. The excitation function for the 1n, 2n and 3n evaporation channels was measured. In the case of the 2n-evaporation channel 250 No, a strong variation of the ground state and isomeric state populations as a function of bombarding energy could be evidenced. [ABSTRACT FROM AUTHOR]

In this paper, we have studied all possible 4 8 Ca and 5 8 Fe -induced fusion reactions for the synthesis of superheavy nuclei 1 0 4 ≤ Z ≤ 1 2 5. The semi-empirical formula for fusion barriers of 4 8 Ca and 5 8 Fe is constructed. Fusion and evaporation residue cross-sections are studied using advance statistical model (ASM). The fusion and evaporation residue cross-sections of this work are compared with that of experiments. We have also predicted suitable targets and production cross-sections for the synthesis of superheavy elements using the 4 8 Ca and 5 8 Fe -induced fusion reactions. The 5 8 Fe -induced fusion reactions can be used to synthesize superheavy elements Z = 1 2 0 , 1 2 2 and 124 using the targets 2 4 5 Cm, 2 4 9 Bk and 2 4 9 Cf have half-lives greater than one year and produce the cross-sections in terms of pb. [ABSTRACT FROM AUTHOR]

A novel combination of advanced gas-chromatography and detection systems coupled to a buffer-gas cell was characterized on-line to allow gas-phase chemical studies of accelerator-produced short-lived α -decaying mercury, francium, and astatine isotopes. These were produced in 40Ar- and 48Ca-induced nuclear fusion–evaporation reactions, subsequently isolated in the recoil separators MARS at Texas A&M University, USA, and TASCA at GSI Darmstadt, Germany, before being thermalized in a buffer-gas-stopping cell. From the latter, the nuclear reaction products were extracted into gas-phase chromatographic systems, suitable for registering α -decaying short-lived radionuclides, such as isotopes of superheavy elements. Efficiencies of 21(3)% for 204-209Fr were reached for the extraction into the optimized miniCOMPACT gas-chromatography setup, indicating that this technique enables the identification of isotopes of volatile as well as non-volatile elements. These studies guide the path towards chemical investigations of superheavy elements beyond flerovium, which are out of reach with currently used setups. [ABSTRACT FROM AUTHOR]

Excited states in 1 2 6 , 1 2 8 Xe were populated via 1 2 2 Sn(9Be, 5n γ) and 1 2 2 Sn(9Be, 3n γ) fusion-evaporation reactions, respectively, at a beam energy of 48 MeV. The electromagnetic (electric or magnetic) nature and multipolarity of some inter-band γ rays are determined from linear polarization and angular correlation measurements. Re-measured/newly measured linear polarization asymmetry helps to assign the parity of 2302-keV ( 1 2 6 Xe)/2228-keV ( 1 2 8 Xe) I π = 5 − state unequivocally. [ABSTRACT FROM AUTHOR]

This work theoretically analyzed the role played by intrinsic degrees of freedom of the colliding partners and/or nucleon transfer channel in the fusion dynamics of 1 2 C + 9 2 Zr and 1 2 C + 1 9 4 , 1 9 8 Pt reactions. The theoretical calculations for the chosen reactions have been done by using symmetric–asymmetric Gaussian barrier distribution (SAGBD) model, coupled channel code CCFULL and one-dimensional Wong formula. The fusion excitation functions for these reactions are enhanced at energies lying in the sub-barrier regions with respect to calculations based on one-dimensional Wong formula. Such enhancement can be ascribed to the involvement of the low-lying inelastic surface excitations of the colliding systems and some other favored channels. The CCFULL calculations consider the couplings to low lying vibrational states of target isotopes and hence intimate the dominance of the collective excitations associated with the fusing partners. For all the studied reactions, the SAGBD model adequately addresses the sub-barrier fusion dynamics and thus the impacts of nuclear structure degrees of freedom associated with the collision partners are intrinsically incorporated via single Gaussian type of weight function. In the SAGBD approach, the nuclear structure effects are analyzed in terms of channel coupling parameter (λ) and percentage reduction of effective fusion barrier V CBRED with reference to the Coulomb barrier. The larger values for λ and V CBRED imply that the channel couplings due to internal structure of participants are significant at below barrier energies. The CCFULL calculations and SAGBD predictions consistently explain the fusion dynamics of chosen systems and hence reveal that both models have almost similar predictive power with respect to reported fusion data. [ABSTRACT FROM AUTHOR]

We provide theoretical and simulation analysis of the small signal response of SiO2/AlGaN/GaN metal insulator semiconductor (MIS) capacitors from depletion to spill over region, where the AlGaN/SiO2 interface is accumulated with free electrons. A lumped element model of the gate stack, including the response of traps at the III-N/dielectric interface, is proposed and represented in terms of equivalent parallel capacitance, Cp, and conductance, Gp, . Cp, -voltage and Gp, -voltage dependences are modelled taking into account bias dependent AlGaN barrier dynamic resistance Rbr, and the effective channel resistance. In particular, in the spill-over region, the drop of Cp, with the frequency increase can be explained even without taking into account the response of interface traps, solely by considering the intrinsic response of the gate stack (i.e., no trap effects) and the decrease of Rbr, with the applied forward bias. Furthermore, we show the limitations of the conductance method for the evaluation of the density of interface traps, Dit, from the Gp,/ω vs. angular frequency ω curves. A peak in Gp/ω vs. ω occurs even without traps, merely due to the intrinsic frequency response of gate stack. Moreover, the amplitude of the Gp/ vs. ω peak saturates at high Dit, which can lead to underestimation of Dit. Understanding the complex interplay between the intrinsic gate stack response and the effect of interface traps is relevant for the development of normally on and normally off MIS high electron mobility transistors with stable threshold voltage. [ABSTRACT FROM AUTHOR]

Highly ionized heavy evaporation residues (ERs) resulting from heavy-ion (HI) fusion–evaporation reactions are knocked out from solid targets to rarefied gas of gas-filled recoil separators. In gas, these ERs undergo charge-changing collisions on their way to a detection system. An equilibrium between the loss of charge (electron capture) and the gain of charge (electron loss) for ionized ERs allows one to use equilibrated charge-state distributions in trajectory calculations for ERs moving through a magnetic field. The distance from a target to the point where the ER charge-state distributions become to be the equilibrated one is essential for such calculations. This distance can be estimated in simulations based on electron capture and loss cross sections for energetic HIs. Reasonable approximations of available experimental data have provided these cross sections, which were applied to the Monte Carlo simulations of the ionic charge evolution for highly ionized heavy ERs. The results of these simulations demonstrate the setting of charge equilibration close to the target. [ABSTRACT FROM AUTHOR]

In-beam γ -ray spectroscopy of 1 2 7 I was carried out following 1 2 4 Sn(7Li, 4n γ) fusion-evaporation reaction at a beam energy of 33 MeV. Ratio of the electric dipole (E1) and electric quadrupole (E2) transition probabilities [B(E1)/B(E2)] for the transitions depopulating from the I π = 1 5 / 2 − , 1 9 / 2 − states have been extracted from this study. Existence of enhanced E1 transition rates between the opposite parity bands, associated dominantly with [ 4 0 2 ] 5 / 2 + and [ 5 5 0 ] 1 / 2 − configurations, provides an indication of octupole correlations in this nucleus [ABSTRACT FROM AUTHOR]

The level lifetimes of the 2 1 + and 4 1 + states in 182 Pt have been re-measured employing the γ – γ fast-timing technique using fast LaBr 3 (Ce) scintillators. Excited states in the nucleus of interest were populated by the fusion-evaporation reaction 170 Yb (16 O , 4n) 182 Pt at a beam energy of 87 MeV provided by the FN Tandem accelerator of the University of Cologne. The lifetime of the 2 1 + state was re-measured with high accuracy to be τ = 563 (12) ps and resolves inconsistencies from previous measurements. Experimental results are compared to theoretical calculations in the framework of the sd-IBM with and without configuration mixing. [ABSTRACT FROM AUTHOR]

A promising method for the production and extraction of 52Fe utilizing near-symmetric, heavy-ion fusion-evaporation reactions is presented. A 28Si beam was used to bombard a 27Al target, producing 52Fe through the reaction: 27Al (28Si, p2n)52Fe. After irradiation, the aluminum target was dissolved, and the 52Fe was separated from the aluminum matrix and other reaction products through the use of a cationic-exchange column. It was possible to recover the 52Fe (t 1/2 = 8.3 h) with high specific activity, higher than can be achieved with the high energy proton spallation reactions currently used to produce this isotope, which has significance in medical research. The production yields for this reaction were measured and compared to PACE4 calculations. These results demonstrate the potential for dedicated accelerator production of 52Fe using heavy-ion beams, which will result in higher specific activities with robust radiochemical purification techniques. [ABSTRACT FROM AUTHOR]

In this work, a new method of range verification for proton therapy (PT) is experimentally demonstrated for the first time. If a metal marker is implanted near the tumour site, its response to proton activation will result in the emission of characteristic γ rays. The relative intensity of γ rays originating from competing fusion-evaporation reaction channels provides a unique signature of the average proton energy at the marker, and by extension the beam's range, in vivo and in real time. The clinical feasibility of this method was investigated at the PT facility at TRIUMF with a proof-of-principle experiment which irradiated a naturally-abundant molybdenum foil at various proton beam energies. Delayed characteristic γ rays were measured with two Compton-shielded LaBr3 scintillators. The technique was successfully demonstrated by relating the relative intensity of two γ-ray peaks to the energy of the beam at the Mo target, opening the door to future clinical applications where the range of the beam can be verified in real time. [ABSTRACT FROM AUTHOR]

High spin states in 104Pd were populated via 94Zr(13C, 3nγ) fusion-evaporation reaction at a beam energy of 55 MeV. The Indian National Gamma Array was utilized to detect the de-exciting γ-rays. Lifetimes of states in the negative parity bands have been determined using the Doppler shift attenuation method. The present lifetime results suggest a moderate quadrupole deformation (β2 ≈ 0.2) for the negative parity bands. The Woods–Saxon total Routhian surface calculations have also been carried out which predicted a similar deformation for these bands. In addition, lifetimes of states in the positive parity band have also been determined. Present results found in agreement with the earlier reported values of lifetimes and hence agreed with the antimagnetic rotational character of the band as interpreted earlier. [ABSTRACT FROM AUTHOR]