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The cross-sections of (d,p), (d,n) and (d,t) transfer reactions are analyzed depending on different density distributions, temperature cases, nuclear potentials and nucleon-nucleon interactions. The calculations are based on the DWBA method. The theoretical results and experimental data are compared, and the analyzes are made about the similarities and differences of the results. Additionally, new potential parameter sets for each transfer reaction are developed. Finally, alternative density, nuclear potential and nucleon-nucleon interactions are proposed for the analysis of (d,p), (d,n) and (d,t) transfer reactions. [ABSTRACT FROM AUTHOR]

Monte Carlo simulations are widely used in nuclear physics to model experimental systems. In cases where there are significant unknown quantities, such as energies of states, an iterative process of simulating and fitting is often required to describe experimental data. We describe a Bayesian approach to fitting experimental data, designed for data from a 12Be(d,p) reaction measurement, using simulations made with GEANT4. Q-values from the 12C(d,p) reaction to well-known states in 13C are compared with simulations using BayesOpt. The energies of the states were not included in the simulation to reproduce the situation for 13Be where the states are poorly known. Both cases had low statistics and significant resolution broadening owing to large proton energy losses in the solid deuterium target. Excitation energies of the lowest three excited states in 13C were extracted to better than 90 keV, paving a way for extracting information on 13Be.

KoBRA can produce RI beams with energies of 5–10 MeV/u from stable ion beams (10–40 MeV/u) delivered from the superconducting linear accelerator SLC3 of RAON. In its early phase of operation, transfer reaction measurements with these RI beams can be performed for nuclear astrophysics studies. SNACK has been developed at RISP in order to measure the light ejectiles from the transfer reactions. With the beam trajectories obtained from upstream PPACs, excitation energy levels in the heavy recoils can be reconstructed by measuring light ejectile's energies and scattering angles. The expected results of transfer reaction measurements with SNACK and KoBRA beamline detectors were calculated by using a Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

BackgroundThe pre-equilibrium cluster manifests the nuclear structure and reaction dynamics of collision system. The systematical investigation of cluster emission in transfer reactions is of significance in deep understanding of the synthesis of superheavy nuclei, shell evolution, new isotope production, etc.PurposeThe dynamics of pre-equilibrium cluster in a few of nucleon transfer reaction has been described by theoretical model, such as exciton model, cluster model. However, the cluster emission in massive transfer is very complicated because of the emission mechanism associated with the structure properties and also the dynamical process.MethodsIn this work, the pre-equilibrium cluster emission in massive transfer reaction has been systematically investigated within the dinuclear system model. The model has been successfully used for describing the massive fusion reaction and multi-nucleon transfer dynamics. The nucleon exchange and energy dissipation take place once the dinuclear system is formed. The nucleon transfer between the binary fragments is governed by the single-particle Hamiltonian and proceeds around the Fermi surface formed by the dinuclear system. The master equation is used for the nucleon transfer dynamics and the relative motion energy dissipation is taken into account. The dynamics of neutron, proton, deuteron, triton, 3He, 4He, 6,7Li and 8,9Be in collisions of 12C+209Bi, 40Ca+208Pb and 48Ca+238U near Coulomb barrier energies is analyzed, i.e., temporal evolution of production rate, kinetic energy spectra and angular distribution.ResultsIt is found that the emission probability of 4He is the same magnitude of proton emission and several orders larger than the one of 3He. Both the nuclear structure and dynamical effects influence the pre-equilibrium cluster production.ConclusionsThe pre-equilibrium clusters are emitted from the 'projectile-like' and 'target-like' fragments and the angular distributions manifest the similar trends. The kinetic energy spectra of clusters are shown as the Boltzmann distribution. The method is also extended to the cluster emission in weakly bound nuclei induced reactions by considering the preformation factor for the cluster construction.

Monte Carlo simulations are widely used in nuclear physics to model experimental systems. In cases where there are significant unknown quantities, such as energies of states, an iterative process of simulating and fitting is often required to describe experimental data. We describe a Bayesian approach to fitting experimental data, designed for data from a 12Be(d,p) reaction measurement, using simulations made with GEANT4. Q-values from the 12C(d,p) reaction to well-known states in 13C are compared with simulations using BayesOpt. The energies of the states were not included in the simulation to reproduce the situation for 13Be where the states are poorly known. Both cases had low statistics and significant resolution broadening owing to large proton energy losses in the solid deuterium target. Excitation energies of the lowest three excited states in 13C were extracted to better than 90 keV, paving a way for extracting information on 13Be. [ABSTRACT FROM AUTHOR]

The spin-orbit splitting between neutron 1 p orbitals at 33Si has been deduced using the single-neutron-adding (d , p) reaction in inverse kinematics with a beam of 32Si, a long-lived radioisotope. Reaction products were analyzed by the newly implemented SOLARIS spectrometer at the reaccelerated-beam facility at the National Superconducting Cyclotron Laboratory. The measurements show reasonable agreement with shell-model calculations that incorporate modern cross-shell interactions, but they contradict the prediction of proton density depletion based on relativistic mean-field theory. The evolution of the neutron 1 p -shell orbitals is systematically studied using the present and existing data in the isotonic chains of N = 17 , 19, and 21. In each case, a smooth decrease in the separation of the 1 p 3 / 2 - 1 p 1 / 2 orbitals is seen as the respective p -orbitals approach zero binding, suggesting that the finite nuclear potential strongly influences the evolution of nuclear structure in this region. [ABSTRACT FROM AUTHOR]

To investigate the chemical effect on the muon capture process through a muon transfer reaction from a muonic hydrogen atom, the formation rate of muonic carbon atoms is measured for benzene and cyclohexane molecules in liquid samples. The muon transfer rate to carbon atoms of the benzene molecule is higher than that to the carbon atoms of the cyclohexane molecule. Such a deviation has never been observed among those molecules for gas samples. This may be because the transfers occur from the excited states of muonic hydrogen atoms in the liquid system, whereas in the gas system, all the transfers occur from the 1s (ground) state of muon hydrogen atoms. The muonic hydrogen atoms in the excited states have a larger radius than those in the 1s state and are therefore considered to be affected by the steric hindrance of the molecular structure. This indicates that the excited states of muonic hydrogen atoms contribute significantly to the chemical effects on the muon transfer reaction. [ABSTRACT FROM AUTHOR]

Chemical group‐transfer reactions by hydrolytic enzymes have considerable importance in biocatalytic synthesis and are exploited broadly in commercial‐scale chemical production. Mechanistically, these reactions have in common the involvement of a covalent enzyme intermediate which is formed upon enzyme reaction with the donor substrate and is subsequently intercepted by a suitable acceptor. Here, we studied the glycosylation of glycerol from sucrose by sucrose phosphorylase (SucP) to clarify a peculiar, yet generally important characteristic of this reaction: partitioning between glycosylation of glycerol and hydrolysis depends on the type and the concentration of the donor substrate used (here: sucrose, α‐d‐glucose 1‐phosphate (G1P)). We develop a kinetic framework to analyze the effect and provide evidence that, when G1P is used as donor substrate, hydrolysis occurs not only from the β‐glucosyl‐enzyme intermediate (E‐Glc), but additionally from a noncovalent complex of E‐Glc and substrate which unlike E‐Glc is unreactive to glycerol. Depending on the relative rates of hydrolysis of free and substrate‐bound E‐Glc, inhibition (Leuconostoc mesenteroides SucP) or apparent activation (Bifidobacterium adolescentis SucP) is observed at high donor substrate concentration. At a G1P concentration that excludes the substrate‐bound E‐Glc, the transfer/hydrolysis ratio changes to a value consistent with reaction exclusively through E‐Glc, independent of the donor substrate used. Collectively, these results give explanation for a kinetic behavior of SucP not previously accounted for, provide essential basis for design and optimization of the synthetic reaction, and establish a theoretical framework for the analysis of kinetically analogous group‐transfer reactions by hydrolytic enzymes. [ABSTRACT FROM AUTHOR]

Tuberculosis is a major public health problem in developing countries. It is one of the most widely spread human diseases globally. While the new diagnostics for tuberculosis (TB) have created greater interest, their full impact on global propaganda against tuberculosis is yet to be evaluated. Most of the TB cases are prevalent in the underdeveloped and developing regions of the world where the means to diagnose and to treat TB cases are limited. As a result, the infectious TB cases might remain undiagnosed or diagnosed late. So, the need of the hour is to launch a rapid but simple, inexpensive, sensitive and specific test to diagnose TB cases at the earliest. The abundant presence of glutamine synthetase (GS) in the culture filtrate of pathogenic mycobacteria has correlation with the occurrence of poly L-glutamate/glutamine component in the cell wall of these pathogenic mycobacteria but not in non-pathogenic mycobacteria. The GS seems to be stable in the infected host and also is present in host tissues and fluid. GS is demonstrated to be present in the serum of subjects suffering from pulmonary or extra-pulmonary tuberculosis; but not detectable at all in normal control and disease control (lung disease control) subjects. With anti-tubercular (A-TB) drug therapy in pulmonary and extra-pulmonary tubercular subjects, the serum GS levels fall significantly. To confirm that only the Mycobacterium tuberculosis (M. tuberculosis) GS is being assayed, the serum GS activity may be assayed in the presence of L-methionine-S, R-sulfoximine (MSO), a selective inhibitor of M. tuberculosis GS. The concentration of this inhibitor is so selected that it is sufficient to inhibit mycobacterial GS activity but not the human (mammalian) GS activity. It increases the specificity of the test. Thus, an ELISA or latex agglutination test might be inducted to assay the serum GS activity for the rapid and reliable detection of active or latent tubercular subjects and also detecting the presence of drug sensitivity or the emergence of resistance against A-TB drugs. Nevertheless, for rapid field study, the card assay technique might be implemented; where when a drop of serum from a suspected subject be placed on the substrate for GS; a definite colour change would mark the test positive. The assay for serum GS requires only a sample of serum from the patient and takes only few minutes to perform. Therefore, the results will be available instantaneously when the patient is at the medical facility centre or even at home and this will curtail the number of visits to the medical facility centre. This is really advantageous in developing and underdeveloped countries where in many cases the patients do not have the capability of making multiple visits to the medical facility centre. The test procedure can also be used as an assay to monitor the response and success of antitubercular drug therapy. The procedure can very well indicate whether the treatment is successful or a change in the antibiotic drug therapy would be needed. [ABSTRACT FROM AUTHOR]

Angular distribution of the 1 0 B + 1 2 C elastic scattering was measured at E lab ( 1 0 B) = 4 1. 3 MeV. Experimental data showed a significant increase in differential cross-sections at backward angles. The optical model with phenomenological potentials reproduces well the experimental cross-sections in the region of the angles of the forward hemisphere, but is not able to explain the increase in cross-sections at large angles. The distorted wave Born approximation method was used to reproduce the experimental data at large angles (> 9 0 ∘) by taking into consideration a deuteron transfer. Spectroscopic amplitude has been extracted for the configuration 1 2 C → 1 0 B + d from the analysis. [ABSTRACT FROM AUTHOR]

Abstract Recently, we have determined surface distributions of α clusters in the ground state of Ne 20 from α -transfer cross sections, without investigating the properties of its excited states. In this paper we extend our comprehension of α -cluster structures in excited states of nuclei through reaction studies. In particular we focus on O 16 , for which attention has been paid to advances of structure theory and assignment regarding 4 + -resonance states. We study the surface manifestation of the α -cluster states in both the ground and excited states of O 16 from the analysis of the α -transfer reaction C 12 (Li 6 , d) 16 O. The α -transfer reaction is described by the distorted-wave Born approximation. We test two microscopic wave functions as an input of reaction calculations. Then a phenomenological potential model is introduced to clarify the correspondence between cluster-wave functions and transfer-cross sections. Surface peaks of the α -wave function of O 16 (0 +) are sensitively probed by transfer-cross sections at forward angles, while it remains unclear how we trace the surface behavior of O 16 (4 +) from the cross sections. From inspection of the cross sections at forward angles, we are able to specify that the α -cluster structure in the 0 1 + and 0 2 + states prominently manifests itself at the radii ∼4 and ∼4.5 fm, respectively. It is remarkable that the 4 1 + state has the C 12 + α -cluster component with the surface peak at the radius ∼4 or outer, whereas the C 12 + α -cluster component in the 4 2 + state is found not to be dominant. The 4 2 + state is difficult to be interpreted by a simple potential model assuming the C 12 + α configuration only. [ABSTRACT FROM AUTHOR]

The measurements of cross sections for deuteron elastic scattering and (d,p) reaction on 124Sn nuclei have been performed with aim to study the features of sub-barrier deuteron interaction with heavy nuclei. Experimental data were obtained on the electrostatic Tandem accelerator EGP-10K of the Institute for Nuclear Research (Kyiv) at the deuteron beam energies Ed = 4.0; 5.0 and 5.5 MeV. Cross sections of deuteron elastic scattering were calculated in approach where the deuteron interaction potential with heavy nuclei at sub-barrier energies has been constructed in the framework of single folding model using the complex dynamic polarization potential. It is shown that the account of finite deuteron size leads to the increasing the nuclear potential in outer region of interaction and significantly improves the description of the experimental data. The calculations of elastic scattering cross sections were performed without any variations of the nuclear potential parameters. The analysis of measured integral cross sections of the 124Sn(d,p) reaction and calculated cross sections of deuteron breakup reaction 124Sn(d,p)n124Sn shows the dominant contribution of the neutron transfer reaction in the processes of the formation of protons and elastic scattering cross sections.

Abstract The low energy excited 0 2 , 3 + states in 96Sr are amongst the most prominent examples of shape coexistence across the nuclear landscape. In this work, the neutron [ 2 s 1 / 2 ] 2 content of the 0 1 , 2 , 3 + states in 96Sr was determined by means of the d(95Sr, p) transfer reaction at the TRIUMF-ISAC2 facility using the SHARC and TIGRESS arrays. Spectroscopic factors of 0.19(3) and 0.22(3) were extracted for the 96Sr ground and 1229 keV 0 + states, respectively, by fitting the experimental angular distributions to DWBA reaction model calculations. A detailed analysis of the γ -decay of the isomeric 0 3 + state was used to determine a spectroscopic factor of 0.33(13). The experimental results are compared to shell model calculations, which predict negligible spectroscopic strength for the excited 0 + states in 96Sr. The strengths of the excited 0 2 , 3 + states were also analyzed within a two-level mixing model and are consistent with a mixing strength of a 2 = 0.40 (14) and a difference in intrinsic deformations of | Δ β | = 0.31 (3). These results suggest coexistence of three different configurations in 96Sr and strong shape mixing of the two excited 0 + states. [ABSTRACT FROM AUTHOR]

A new 11 Be( d , p ) 12 Be transfer reaction experiment was carried out in inverse kinematics at 26.9 A MeV, with special efforts devoted to the determination of the deuteron target thickness and of the required optical potentials from the present elastic scattering data. In addition a direct measurement of the cross section for the 0 2 + state was realized by applying an isomer-tagging technique. The s -wave spectroscopic factors of 0.20 − 0.04 + 0.03 and 0.41 − 0.11 + 0.11 were extracted for the 0 1 + and 0 2 + states, respectively, in 12 Be. Using the ratio of these spectroscopic factors, together with the previously reported results for the p -wave components, the single-particle component intensities in the bound 0 + states of 12 Be were deduced, allowing a direct comparison with the theoretical predictions. It is evidenced that the ground-state configuration of 12 Be is dominated by the d -wave intruder, exhibiting a dramatic evolution of the intruding mechanism from 11 Be to 12 Be, with a persistence of the N = 8 magic number broken. [ABSTRACT FROM AUTHOR]

The structure of nuclei provides insight into astrophysical reaction rates that are difficult to measure directly. These studies are often performed with transfer reactions and β-decay measurements. These experiments benefit from particle-γ coincidence measurements which provide information beyond that of particle detection alone. The Hybrid Array of Gamma Ray Detectors (HAGRiD) of LaBr 3 (Ce) scintillators has been designed with this purpose in mind. The design of the array permits it to be coupled with particle detector systems, such as the Oak Ridge Rutgers University Barrel Array (ORRUBA) of silicon detectors and the Versatile Array of Neutron Detectors at Low Energy (VANDLE). It is also designed to operate with the Jet Experiments in Nuclear Structure and Astrophysics (JENSA) advanced target system. HAGRiD’s design avoids compromising the charged-particle angular resolution due to compact geometries which are often used to increase the γ efficiency in other systems. First experiments with HAGRiD coupled to VANDLE as well as ORRUBA and JENSA are discussed. [ABSTRACT FROM AUTHOR]

A transfer-reaction experiment of Be(Be, Be)Be was performed at a beam energy of 45 MeV. Excited states in Be up to 18.80 MeV are produced using missing mass and invariant mass methods. Most of the observed high-lying resonant states, reconstructed from the α + He and t + Li decay channels, agree with the previously reported results. In addition, two new resonances at 15.6 and 18.8 MeV are identified from the present measurement. The 18.55 MeV state is found to decay into both the t + Li. and t + Li* (0.478 MeV) channels, with a relative branching ratio of 0.93 ± 0.33. Further theoretical investigations are encouraged to interpret this new information on cluster structure in neutron-rich light nuclei. [ABSTRACT FROM AUTHOR]

In this paper, the reactions are revisited, with the goal of obtaining spectroscopic factors (SF) for the transition to the ground state of some residual nuclei, applying the distorted wave Born approximation (DWBA). The double-folding São Paulo Potential (SPP) was used to derive the distorted wave function in the entrance and exit channels. The derived SF are compared with the results of extensive shell model calculations showing a rather good agreement. [ABSTRACT FROM AUTHOR]

The 82 Ge beam has been produced by the in-flight fission reaction of the 238 U primary beam with 345 MeV/u at the RIKEN RI beam factory, and slowed down to about 15 MeV/u using the energy degraders. The momentum-compression mode was applied to the second stage of the BigRIPS separator to reduce the momentum spread. The energy was successfully reduced down to 13 ± 2.5 MeV/u as expected. The focus was not optimized at the end of the second stage, therefore the beam size was larger than the expectation. The transmission of the second stage was half of the simulated value mainly due to out of focus. The two-stage separation worked very well for the slowed-down beam with the momentum-compression mode. [ABSTRACT FROM AUTHOR]

The first measurement of the one-neutron transfer reaction 11 Li(p,d) 10 Li performed using the IRIS facility at TRIUMF with a 5.7 A MeV 11 Li beam interacting with a solid H 2 target is reported. The 10 Li residue was populated strongly as a resonance peak with energy E r = 0.62 ± 0.04 MeV having a total width Γ = 0.33 ± 0.07 MeV . The angular distribution of this resonance is characterized by neutron occupying the 1 p 1 / 2 orbital. A DWBA analysis yields a spectroscopic factor of 0.67 ± 0.12 for p 1 / 2 removal strength from the ground state of 11 Li to the region of the peak. [ABSTRACT FROM AUTHOR]

The reaction C()O was investigated through the direct -transfer reaction (7Li,t) at 28 and 34 MeV incident energies. We determined the reduced -widths of the sub-threshold 2 and 1 states of O from the DWBA analysis of the transfer reaction C(7Li,t)O performed at two incident energies. The obtained result for the 2 and 1 sub-threshold resonances as introduced in the -matrix fitting of radiative capture and elastic-scattering data to determine the E2 and E1 -factor from 0.01MeV to 4.2MeV in the center-of-mass energy. After determining the astrophysic factor of C()O S(E) with Pierre Descouvement code, I determined numerically the new reaction rate of this reaction at a different stellar temperature (0.06 Gk-2 GK). The C()O reaction rate at T is [7.21] × 10 cm3 s mol. Some comparisons and discussions about our new C()O reaction rate are presented. The agreements of the reaction rate below T between our results and with those proposed by NACRE indicate that our results are reliable, and they could be included in the astrophysical reaction rate network. [ABSTRACT FROM AUTHOR]

The measurements of cross sections for deuteron elastic scattering and (d, p) reaction on 124Sn nuclei have been performed with aim to study the features of sub-barrier deuteron interaction with heavy nuclei. Experimental data were obtained on the electrostatic Tandem accelerator EGP-10K of the Institute for Nuclear Research (Kyiv) at the deuteron beam energies Ed = 4.0; 5.0 and 5.5 MeV. Cross sections of deuteron elastic scattering were calculated in approach where the deuteron interaction potential with heavy nuclei at sub-barrier energies has been constructed in the framework of single folding model using the complex dynamic polarization potential. It is shown that the account of finite deuteron size leads to the increasing the nuclear potential in outer region of interaction and significantly improves the description of the experimental data. The calculations of elastic scattering cross sections were performed without any variations of the nuclear potential parameters. The analysis of measured integral cross sections of the 124Sn(d, p) reaction and calculated cross sections of deuteron breakup reaction 124Sn(d, p)n124Sn shows the dominant contribution of the neutron transfer reaction in the processes of the formation of protons and elastic scattering cross sections. [ABSTRACT FROM AUTHOR]