Energy calibration of HPGe detector using the high-energy characteristic γ rays in 13C formed in 6Li + 12C reaction

An 6 Li+89Y experiment was conducted at the Laboratori Nazinali di Legnaro,INFN,Italy.The 550μg/cm^2 thick^89Y target was backed on a 340μg/cm^2 thick 12C foil.The severalγrays in the experiment with energies higher than 3000 keV can most likely be ascribed to the transitions in the 13C nuclei,which can be formed through various interactions between the 6 Li beam and the 12C foil.The high-energy properties ofγrays in 13C are employed for energy calibrating HPGe detectors,especially for the>3000 keV region,which is impossible to reach by common standard sources(152Eu,133Ba,etc.).Furthermore,γ-γand particle-γcoincidence measurements were performed to investigate the formation of 13C.

Study of ATP borate ester effects on cell sensitization to radiation emitted by a nuclear reactor

Adenosine triphosphate(ATP)borate ester as a new boron agent for boron neutron capture therapy was tested.It was synthesized via a dehydration reaction induced by heating adenosine triphosphate disodium with boric acid.Next,ATP borate ester pretreatments were assessed to study their effects on cell sensitization from exposure to thermal neutron irradiation emitted by a nuclear reactor.Using cell viability assays(CCK8),survival rates of A549 cells pretreated with or without boroncontaining agents,including ATP borate ester and 4-dihydroxyborylphenylalanine(BPA),were measured.One week after feeding an ATP borate ester solution to tumorbearing nude mice,elemental B content values of tumor muscle and blood were measured using inductively coupled plasma mass spectrometry(ICP-MS).Meanwhile,other tumor tissue samples were placed in a culture medium,subjected to a 3-min neutron irradiation exposure,and then fixed in formalin 24 h later for the terminaldeoxynucleotidyl transferase(TDT)-mediated d UTP nick end labeling(TUNEL)immunohistochemical staining analysis.Results showed that A549 cell irradiation sensitization(irradiation dose of 0.33 Gy)varied with pretreatment.Sensitization values of the ATP borate ester pretreatment group were 1.3–14.1 with boron agent concentrations of 0.3–4.5 mM.Within 1.1–3.4 mM,ATP borate ester showed significantly higher sensitization values than BPA.Meanwhile,TUNEL results demonstrated that apoptosis rates of tumor tissue cells exposed to irradiation after ATP borate ester pretreatment significantly exceeded the corresponding rates for BPA-pretreated cells.In animal experiments,although the distribution ratio of ATP borate ester(tumor tissue/normal muscle,T/N)of 1.2 was not significantly different compared with that of BPA(1.3),the total ATP borate ester concentration in the tumor tissue(0.79±0.05μg/g)significantly exceeded that of BPA(0.58±0.05μg/g).Thus,compared with BPA,the greater enrichment of ATP borate ester in tumor tissues permits preferential targeting toward tumor cells for radiation sensitization.Therefore,ATP borate ester is superior to BPA for use in boron neutron capture therapy.

Lifetime measurements in 138Nd

Lifetimes of the 2_(1)^(+),4_(1)^(+),7_(2)^(-),10_(2)^(+),12_(2)^(+),and 14_(1)^(+) states in 138 Nd populated via the 123 Sb(19 F,4n)138 Nd fusion–evaporation reaction were measured with the recoil distance Doppler shift technique in combination with the differential decay curve method.The B(E2;2_(1)^(+)→0_(1)^(+))value fit well with the systematic trend in the Nd isotope chain and Grodzins rule,which proved that 138Nd is a transitional nucleus.

Low-lying states of 92,93Nb excited in the reactions induced by the weakly-bound nucleus 6Li near the Coulomb barrier

Excited states of odd-odd nucleus 92Nb and odd-A nucleus 93Nb were populated in the 6Li+ 89Y reaction with an incident energy of 34 MeV. The processes that produce 92,93Nb and can be measured by a combination of light charged particle and gamma ray measurements are discussed. Twenty new transitions are observed and eight new levels are constructed in 92Nb, and in addition two new transitions are added to the level scheme of 93Nb. Using shell model calculations, the low-lying structure of 92Nb is investigated and compared with the experimental results.

High spin states in ^(71)Ga

Excited states in the odd-A nucleus 71Ga have been studied via the ^(70)Zn(7Li,a2n)^(71)Ga fusion-evaporation reaction with incident beam energies of 30 and 35 MeV.The level scheme is established up to spin I^(n)=(29/2^(+))and an excitation energy-6.6 MeV.A previously known sequence built on the 9/2^(+) state is extended as a novel rotational band originating from the v(8^(2)_(9/2)alignment.Furthermore,a negative-parity sequence Is also reported.The observed energy levels of Ga have been interpreted in the framework of the nuclear shell model(SM).

Systematic study of the Woods-Saxon potential parameters between heavy-ions

Experimental elastic scattering angular distributions of 11B,2C,and 16O+heavy-ions are used to studythe Woods-Saxon potential parameters.Best fitted values of the diffuseness parameters are found for each system,and a linear relationship is expressed between the diffuseness parameters and A1/31+A1/32.The correlation of the po-tential depth and radius parameters with A1/31+A1/32is also revealed within the limitations of the diffuseness parameter formula.Because the incident energies of most of the analyzed reactions are below or around the Coulombbarrier,the energy dispersion relation between the real and imaginary potentials is considered in order to investigatethe ratio between the imaginary and real potential well depths,resulting in an expression of W/V.Within the limitation of the volume integrals calculated with the Sao Paulo potential,parameterized formulas for the depth and radius parameters are obtained.The systematic Woods-Saxon potential parameters derived in the present work can reproduce not only the experimental data of elastic scattering angular distributions induced by 11B,12C,and 16O butalso some elastic scattering induced by other heavy-ions.

Lifetime measurement for the 2^+1 state in^106Cd

The lifetime of the 2^+1 state in ^106Cd populated via the ^94Zr(^16O,4n)^106Cd reaction has been measured with the Recoil Distance Doppler Shift technique in combination with the Differential Decay Curve Method.By subtracting the contamination in the data,the mean lifetime of the I^π=2^+1633 keV state was determined as 9.9(12)ps.The B(E2)value calculated in this study is in good agreement with the experimental systematics and was compared to the shell model calculations.