The quantification of isotopes content in materials is extremely important in many research and industrial fields. Accurate determination of boron concentration is very critical in semiconductor, superconductor and steel industry, in environmental and medical applications as well as in nuclear and astrophysics research. The detection of B isotopes and of their ratio in synthetic and natural materials may be accomplished by gamma spectroscopy using the $^{10}$B(p,$α_1 γ$)$^7$Be and $^{11}$B(p,$γ$)$^{12}$C reactions at low proton energy. Here, the $^{10}$B(p,$α_1 γ$)$^7$Be cross section is reported in the center of mass energy range 0.35 to 1.8 MeV. The $E_γ$= 429 keV $γ$ rays were detected at 45$^\circ$ and 90$^\circ$ using a NaI(Tl) and an HPGe detectors, respectively. In the presented energy range, previous cross sections data revealed discrepancies and normalisation issues. Existing data are compared to the new absolute measurement and discussed. The present data have been subtracted from a previous measurement of the total cross section to derive the contribution of the $α_0$ channel.
In this paper, the production and spectroscopic investigation of Mercury and Radon isotopes was performed using complete fusion reactions neutron evaporation residues and multi-nucleon transfer reaction at the mass-separator MASHA. The MASHA setup is installed on the beam line of Cyclotron U-400M at Flerov Laboratory of Nuclear Reactions (FLNR) in Joint Institute for Nuclear Research (JINR), Dubna, Russia. The isotopes produced in complete fusion reactions 148Sm(40Ar, xn)188-xHg, 166Er(40Ar, xn)206-xRn and multi-nucleon transfer reaction 48Ca + 242Pu were passed through the magnetooptical syst…
Investigation of cluster structure of light nuclei H, He and Li isotopes, in three-body final states photodisintegration processes in the energy range 50-250 MeV using photon beams of Yerevan Synchrotron
Proton elastic scattering from tin isotopes at 295 MeV and systematic change of neutron density distributions
在295 MeV的质子弹性散射截面和分析能力从$^{116,118,120,122,124}$锡已被测量的动量转移高达约3.5 fm $^{-1}$推断系统的中子密度分布的变化。我们调整的相对论洛夫-弗兰尼相互作用,以解释质子的弹性散射的核的密度分布是众所周知的。然后,我们应用这种相互作用推导了锡同位素的中子密度分布。我们的分析结果表明,随着质量数的增加,锡同位素的中子皮厚度逐渐增加的明显的系统行为。
We studied the production of neutron-rich nuclides in multinucleon transfer collisions of stable and radioactive beams in the mass range A=40-60. We first presented our experimental cross section data of projectile fragments from the reaction of 40Ar(15 MeV/nucleon) with 64Ni, 58Ni and 27Al. We then compared them with calculations based on either the deep-inelastic transfer (DIT) model or the constrained molecular dynamics (CoMD) model, followed by the statistical multifragmentation model (SMM). An overall good agreement of the calculations with the experimental data is obtained. We continued …
Photonuclear reactions on stable isotopes of cadmium and tellurium at bremsstrahlung end-point energies of 10-23 MeV
Joint Institute for Nuclear Research(联合核研究所);Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan(乌兹别克斯坦共和国科学院核物理研究所);Skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow State University(莫斯科国立大学斯科别尔琴核物理研究所);Faculty of Physics of Lomonosov Moscow State University(莫斯科国立大学物理系);Bogoliubov Laboratory of Theoretical Physics of Joint Institute for Nuclear Research(联合核研究所博戈留博夫理论物理实验室);Dzhelepov Laboratory of Nuclear Problems of Joint Institute for Nuclear Research(联合核研究所杰列波夫核问题实验室);Institute of Nuclear Physics, Almaty(阿拉木图核物理研究所)
Experimental isomeric yield ratios for the 113In(γ,n)112m,gIn reactions on the betatron B25/30 bremsstrahlung gamma beam of energy range 12-25 MeV are measured. Effective cross-sections of (γ,n)-reactions with 112mIn and 114mIn isomers output are calculated. The Penfold-Leiss and Tikhonov methods are applied to solve the Volterra integral equation. The obtained experimental cross-sections are compared with theoretical calculations using the TALYS-1.6 code.
The stellar reaction rates of radiative $α$-capture reactions on heavy isotopes are of crucial importance for the $γ$ process network calculations. These rates are usually derived from statistical model calculations, which need to be validated, but the experimental database is very scarce. This paper presents the results of $α$-induced reaction cross section measurements on iridium isotopes carried out at first close to the astrophysically relevant energy region. Thick target yields of $^{191}$Ir($α$,$γ$)$^{195}$Au, $^{191}$Ir($α$,n)$^{194}$Au, $^{193}$Ir($α$,n)$^{196m}$Au, $^{193}$Ir($α$,n)$^…
The intensity interferometry is applied as a chronometer of the particle emission of hydrogen isotopes from the intermediate velocity source formed in $^{40}$Ar+$^{197}$Au reactions at 30 MeV/u. The dynamic emission order of $τ_{\rm p}>τ_{\rm d}>τ_{\rm t}$ is evidenced via the correlation functions of nonidentical particle pairs. Assuming the similar source size, the same emission order is inferred from the correlation functions of identical particle pairs, where $τ_{\rm p} \approx 100 {\rm ~fm/c}$ is extracted by the fit of Koonin-Pratt equation to p-p correlation function. Transport model si…
Observation of hidden nuclear reactions on fast neutron-irradiated Lu isotopes
International Nuclear Safety Center of Ukraine of Taras Shevchenko National University of Kyiv(基辅塔拉斯舍甫琴科国立大学乌克兰国际核安全中心);Department of Nuclear and High Energy Physics, Faculty of Physics, Taras Shevchenko National University of Kyiv(基辅塔拉斯舍甫琴科国立大学物理学院核与高能物理系);HUN-REN Institute for Nuclear Research (HUN-REN ATOMKI)(匈牙利研究与创新网络原子核研究所)
Experimental excitation functions for long-lived products in proton induced reactions were measured with the activation method in the 37-65 MeV energy range on natural holmium. Stacked foil irradiation technique and high resolution gamma spectrometry were used in order to measure cross-section data for the production of $^{161}$Er, $^{160}$Er and $^{159,157}$Dy. For comparison of the production routes of medically related $^{161}$Er and $^{160}$Er radioisotopes new experimental cross section data were deduced for the $^{162}$Er(p,x)$^{161,160}$Er and $^{162}$Er(d,x)$^{161,160}$Er reactions by …
The neutron-deficient Ca isotopes continue to attract attention due to their importance for testing isospin symmetry and their relevance in capture reactions of interest for nova nucleosynthesis and the shape of light curves in Type I X-ray bursts. To date, spectroscopic information on 38,39 Ca is largely limited to data on lower-spin excited states. Here, we report in-beam γ-ray spectroscopy of complementary higher-spin, complex-structure states in 39 Ca populated in fast-beam-induced, momentum-dissipative processes leading to neutron pickup onto excited configurations of the projectile, 9 Be…
The production of alpha particle decaying heavy nuclei in reactions of 7.5-6.1 MeV/nucleon $^{238}$U +$^{232}$Th has been explored using an in-beam detection array composed of YAP scintillators and gas ionization chamber-Si telescopes. Comparisons of alpha energies and half-lives for the observed products with those of the previously known isotopes and with theoretically predicted values indicate the observation of a number of previously unreported alpha emitters. Alpha particle decay energies reaching as high as 12 MeV are observed. Many of these are expected to be from decay of previously un…
Muon capture isotope production (MuCIP) using negative ordinary muon capture reactions (OMC) is used to efficiently produce various kinds of nuclear isotopes for both fundamental and applied science studies. The large capture probability of muon into a nucleus, together with the high intensity muon beam, make it possible to produce nuclear isotopes in the order of 10^{9-10} per second depending on the muon beam intensity. Radioactive isotopes (RIs) produced by MuCIP are complementary to those produced by photon and neutron capture reactions and are used for various science and technology appli…
In this review article we discuss the present status of direct nuclear reactions and the nuclear structure aspects one can study with them. We discuss the spectroscopic information we can assess in experiments involving transfer reactions, heavy-ion-induced knockout reactions and quasifree scattering with (p,2p), (p,pn), and (e,e'p) reactions. In particular, we focus on the proton-to-neutron asymmetry of the quenching of the spectroscopic strength.
Exclusive measurements of high energy $γ$-rays are performed in $\rm ^{124}Ba$ and $\rm ^{136}Ba$ at the same excitation energy ($\sim$ 49 MeV), to study properties of the giant dipole resonance (GDR) over a wider $N/Z$ range. The high energy $γ$-rays are measured in coincidence with the multiplicity of low energy $γ$-rays to disentangle the effect of temperature ($T$) and angular momentum ($J$). The GDR parameters are extracted employing a simulated Monte Carlo statistical model analysis. The observed $γ$-ray spectra of $\rm ^{124}Ba$ can be explained with prolate deformation, whereas a singl…
We investigate the possibilities of producing neutron-rich nuclides in projectile fission of heavy beams in the energy range of 20 MeV/nucleon expected from low-energy facilities. We report our efforts to theoretically describe the reaction mechanism of projectile fission following a multinucleon transfer collision at this energy range. Our calculations are mainly based on a two-step approach: the dynamical stage of the collision is described with either the phenomenological Deep-Inelastic Transfer model (DIT), or with the microscopic Constrained Molecular Dynamics model (CoMD). The deexcitati…
Measurement of Proton-Induced Reactions on Lanthanum from 55--200 MeV by Stacked-Foil Activation
Brookhaven National Laboratory(布鲁克海文国家实验室);Los Alamos National Laboratory(洛斯阿拉莫斯国家实验室);University of California, Berkeley(加州大学伯克利分校);Lawrence Berkeley National Laboratory(劳伦斯伯克利国家实验室)
$^{117m}$Sn is one of the radioisotopes can be beneficially produced through alpha particle irradiation. The targets were prepared by deposition of $^{116}$Cd metal onto high purity 12 $μ$m thick Cu backing. The average deposited thickness was 21.9 $μ$m. The beam energy was thoroughly measured by Time of Flight (TOF) methods and proved to be 51.2 MeV. For the experiment the well-established stacked foil technique was used. In addition to the Cd targets, Ti foils were also inserted into the stacks for energy and intensity monitoring. The Cu backings were also used for monitoring and as recoil c…
Aluminium is used as energy degrader or catcher foil or as backing material in nuclear physics experiments. Excitations functions of 27Al+ 20Ne reaction in the projectile energy range 49-166 MeV were measured using stacked foil technique. Various evaporation residues such as 43,44Sc, 41Ar, 34m,38Cl, etc., were identified in the matrix.
The nuclear reaction induced by photon is one of the important tools in the investigation of atomic nuclei. In the reaction, a target material is bombarded by photons with high-energies in the range of gamma-ray energy range. In the bombarding process, the photons can statistically be absorbed by a nucleus in the target material. Then the excited nucleus can decay by emitting proton, neutron, alpha and light particles or photons. By performing photonuclear reaction on the target, it can be easily investigated low-lying excited states of the nuclei. In the present work, (γ, n) photonuclear reac…