scholarly journals Cross Sections for the \(^{nat}\)Zr\((p,xn)^{89,90}\)Nb Reactions Induced by 27.7 MeV Protons

2015 ◽  
Vol 25 (3) ◽  
pp. 257 ◽  
Author(s):  
Pham Duc Khue ◽  
Nguyen Van Do ◽  
Le Tuan Anh
Keyword(s):  
Proton Beam ◽  
Cross Sections ◽  
High Purity ◽  
Hpge Detector ◽  
Nuclear Reactions ◽  
Medical Science ◽  
Activation Method ◽  
Reaction Products ◽  
High Purity Germanium ◽  
Mev Protons

The cross-sections for the formation of \(^{89}\)Nb and  \(^{90}\)Nb radionuclides in proton induced nuclear reactions on zirconium  were measured by using the well known activation method. The natural  zirconium (\(^{nat}\)Zr) target and copper (\(^{nat}\)Cu) monitor foils were  irradiated by 27.7 MeV proton beam at the MC50 Cyclotron of the Korea  Institute of Radiological and Medical Science (KIRAMS), Korea. The induced  gamma activities of the reaction products were measured by a coaxial high  purity germanium (HPGe) detector coupled to a PC-based multichannel  analyzer. The obtained cross sections for each nuclide are compared with  those existing in literature and with the theoretical cross sections  calculated by the TALYS - 1.4 code.

scholarly journals Ratio of spectral averaged cross sections measured in standard 252Cf(sf) and 235U(nth,f) neutron fields

2020 ◽  
Vol 239 ◽  
pp. 19004
Author(s):  
Martin Schulc ◽  
Michal Kostal ◽  
Roberto Capote ◽  
Evzen Novak ◽  
Nicola Burianova ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
High Purity ◽  
Hpge Detector ◽  
High Volume ◽  
Reaction Rates ◽  
Fission Neutron ◽  
Neutron Field ◽  
High Threshold ◽  
High Purity Germanium

The results of systematic evaluations of spectrum averaged cross section (SACS) measurements in the fission neutron fields of 252Cf and 235U are presented. The data form a complete database of high-threshold experimental SACS measured in the same installation under the same conditions and using the same high purity germanium gamma spectrometer. This is crucial to reduce the uncertainty of the ratio and the data scattering and therefore, to minimize discrepancies compared to cross section measured under different conditions in different laboratories. This new dataset complements and extends earlier experimental evaluations. The total emission of the 252Cf neutron source during the experiments varied from 9.5E8 to 4.5E8 neutrons per second. The emission was derived in accordance to the data in the Certificate of Calibration involving absolute flux measurements in a manganese sulphate bath. Concerning 235U fission neutron field, the irradiations were carried out in a specifically designed core assembled in the zero power light water LR-0 reactor. This special core has a well described neutron field. After the irradiation, the low volume irradiated samples to be measured by gamma spectrometry were placed directly on the upper cap of a coaxial high purity germanium (HPGe) detector in a vertical configuration (ORTEC GEM35P4). High volume samples were homogenized and strewn into the Marinelli beaker. The HPGe detector is surrounded by the lead shielding box with a thin inner copper cladding and covered with rubber for suppression of background signal and bremsstrahlung. The experimental reaction rates were derived for irradiated samples from the Net Peak Areas (NPA) measured using the semiconductor HPGe detector. The measured reaction rates are used to derive the spectrum-averaged cross sections. Furthermore, measured reaction rates are also compared with MCNP6 calculations using various nuclear data libraries, in particular IRDFF evaluations.

Measurements of activation cross sections by cyclic activation method for (n,2n) reaction on 144Sm isotope around 14 MeV neutron energy

2018 ◽  
Vol 107 (1) ◽  
pp. 33-37
Author(s):  
Iskender Atilla Reyhancan
Keyword(s):  
Neutron Energy ◽  
Cross Sections ◽  
Hpge Detector ◽  
Neutron Generator ◽  
Activation Method ◽  
Fast Neutrons ◽  
Cyclic Activation ◽  
High Purity Germanium ◽  
Γ Ray ◽  
Activation Cross Sections

Abstract Measurement of activation cross sections for the 144Sm(n,2n)143gSm reaction was performed by Cyclic Activation Method (CAM) around 14 MeV neutron energy. Natural samarium samples were irradiated by the neutrons produced by 3H(2H,n)4He reaction using a neutron generator. Delayed γ ray activities produced by fast neutrons in samples were measured by a high resolution γ ray spectrometer [high-purity Germanium (HpGe) detector]. The measured cross sections are compared with the results of model calculation (STAPRE code) and evaluated data (JEFF 3.0/A).

scholarly journals FORMATION OF 7Be IN NUCLEAR REACTIONS INDUCED BY 85-MeV PROTONS

1966 ◽  
Vol 44 (22) ◽  
pp. 2749-2767 ◽  
Author(s):  
M. S. Lafleur ◽  
N. T. Porile ◽  
L. Yaffe
Keyword(s):  
Cross Sections ◽  
Nuclear Reactions ◽  
Mev Protons ◽  
Good Agreement

Cross sections were measured for the formation of 7Be in targets bombarded with 85-MeV protons. The variation of these cross sections with the mass and neutron-to-proton ratio of the target was investigated.Cross-section calculations were performed on the assumption that 7Be is emitted from the irradiated target as an evaporated particle. Calculated and measured cross sections were in good agreement for medium and heavy targets (A > 55). The calculation underestimated the production of' 7Be in light targets (27 < A < 55).

An overview on radiometric assessment and excess lifetime cancer risk of soil in Pakistan by using High Purity Germanium (HPGe) detector

2020 ◽  
Vol 35 (4) ◽  
pp. 531-543
Author(s):  
Jalil ur Rehman ◽  
Iftikhar Alam ◽  
Nisar Ahmad ◽  
Aslam Hameed ◽  
Alia Nazir ◽  
...  
Keyword(s):  
Cancer Risk ◽  
Gamma Rays ◽  
Human Body ◽  
Natural Radioactivity ◽  
High Purity ◽  
Hpge Detector ◽  
Permissible Limit ◽  
Radioactive Elements ◽  
Naturally Occurring ◽  
High Purity Germanium

AbstractObjectivesThe aim of this study is to compare the natural radioactivity and excess life time cancer risk (ELCR) factor of soil in different regions of Pakistan during last decade. Soil contains various elements and compounds including naturally occurring radioactive elements (238U, 232Th, 40K and 137Cs). Human being, animals and plants are in health risk by contaminations of natural radioactivity in soil and environmental radiometric pollution. Transferring of large amount of the natural radioactive elements in human body by nutrients may cause carcinogenic effects in human body. Pakistani soil has six types as Indus Basin Soil, Bongar Soil, Khaddar Soil, Indus delta soil, Mountainous soil and Sandy Desert Soil. In some northern region of Pakistan, naturally occurring radioactive rocks like uranuium-238 and iridium concentrations present in Gharwandi, Aram, Kingri S, Vitakri Fort Munro, Dera Bugti, Kohlu and Sibbi districts.MethodsIn this reviewed data, gamma rays spectroscopy used to determine the concentrations of 238U, 232Th and 40K with the help of High Purity Germanium (HPGe) detectors. Only the data of HPGe detector collected because of comparisons of different regions of Pakistan.Results and conclusionsMostly, different gamma rays energy peaks of relevant daughter radionuclides of radioactive element were used such as the energy peak lines of daughter radionuclides 214Pb (295.21 and 352 KeV) and 214Bi (609 and 1,120 KeV) used for calculating the 226Ra concentration in soil. In the recent study, it is concluded that average values of concentrations of natural radioactivity in soil in central and north regions of Pakistan are higher than permissible limit but found permissible range in south region of Pakistan. Mean values of ELCR factor were found higher, equal and lower in central, north and south regions than permissible limit, respectively. Generally, no serious health hazard due to natural radioactivity in soil were found.

scholarly journals Proton-induced reactions on Fe, Cu, and Ti from threshold to 55 MeV

2021 ◽  
Vol 57 (3) ◽  
Author(s):  
Andrew S. Voyles ◽  
Amanda M. Lewis ◽  
Jonathan T. Morrell ◽  
M. Shamsuzzoha Basunia ◽  
Lee A. Bernstein ◽  
...  
Keyword(s):  
Cross Sections ◽  
Nuclear Reactions ◽  
National Laboratory ◽  
A Priori ◽  
Theoretical Models ◽  
Security Applications ◽  
Reaction Channels ◽  
Proton Induced Reactions ◽  
Titanium Foils ◽  
Mev Protons

AbstractTheoretical models often differ significantly from measured data in their predictions of the magnitude of nuclear reactions that produce radionuclides for medical, research, and national security applications. In this paper, we compare a priori predictions from several state-of-the-art reaction modeling packages (CoH, EMPIRE, TALYS, and ALICE) to cross sections measured using the stacked-target activation method. The experiment was performed using the Lawrence Berkeley National Laboratory 88-Inch Cyclotron with beams of 25 and 55 MeV protons on a stack of iron, copper, and titanium foils. Thirty-four excitation functions were measured from 4–55 MeV, including the first measurement of the independent cross sections for $$^{\mathrm{nat}}\hbox {Fe}$$ nat Fe (p,x)$$^{49,51}\hbox {Cr}$$ 49 , 51 Cr , $$^{51,{\mathrm{52m}},{\mathrm{52g}},56}\hbox {Mn}$$ 51 , 52 m , 52 g , 56 Mn , and $$^{{\mathrm{58m,58g}}}\hbox {Co}$$ 58 m , 58 g Co . All of the models, using default input parameters to assess their predictive capabilities, failed to reproduce the isomer-to-ground state ratio for reaction channels at compound and pre-compound energies, suggesting issues in modeling the deposition or distribution of angular momentum in these residual nuclei.

Development of gamma spectrometric method for the determination of thorium in phosphoric acid solution

2010 ◽  
Vol 98 (5) ◽  
Author(s):  
N. N. Mirashi ◽  
Satyajeet Chaudhury ◽  
S. K. Aggarwal
Keyword(s):  
Phosphoric Acid ◽  
Acid Solution ◽  
High Purity ◽  
Hpge Detector ◽  
Phosphoric Acid Solution ◽  
Spectrometric Method ◽  
High Purity Germanium

AbstractGamma spectrometric determination of thorium in sintered thoria dissolved in strong phosphoric acid was studied using a high purity germanium (HPGe) detector.

Synthesis and properties of isotopes of the transactinides

2019 ◽  
Vol 107 (9-11) ◽  
pp. 879-915 ◽  
Author(s):  
Sigurd Hofmann
Keyword(s):  
Cross Sections ◽  
Nuclear Reactions ◽  
Theoretical Calculations ◽  
Target Material ◽  
Heavy Ion ◽  
Superheavy Nuclei ◽  
Efficient Production ◽  
Reaction Products ◽  
North East ◽  
The North

Abstract Isotopes of transactinide elements have to be synthesized in nuclear reactions with light or heavy beam particles. The efficient production by neutron capture and subsequent β− decay as it is used for the production of isotopes of actinide elements up to fermium is no longer possible due to the lack of suitable target material. The content of this article is about the synthesis and the study of the decay properties of nuclei to which atomic, respectively proton numbers from Z = 104 to 118 could be unambiguously assigned by physical means. The results identified the reaction products as isotopes of new elements beyond the actinides, the transactinides. As such the elements received names given by the discovers ranging from rutherfordium for element 104 to oganesson for element 118 which completes the 7th row of the Periodic Table of the Elements. Intensive heavy ion beams, sophisticated target technology, efficient electromagnetic ion separators, and sensitive detector arrays were the prerequisites for discovery of the elements from Z = 107 to 118 during the years from 1981 to 2013. The results and the techniques are described. Also given is a historical introduction into early experiments and the theoretical predictions for a possible existence of an island of stability located at the crossing of the next closed shells for the protons and neutrons beyond the doubly magic nucleus 208Pb. The experimental results are compared with recent theoretical calculations on cross-sections and decay modes of these superheavy nuclei, respectively isotopes of superheavy elements. An outlook is given on further improvement of experimental facilities which will be needed for exploration of the extension and structure of the island of superheavy nuclei, in particular for searching for isotopes with longer half-lives predicted to be located in the south east and for isotopes of further new elements expected in the north-east direction of the island at the upper end of the chart of nuclei.

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