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A high-and-flat efficiency moderated neutron detection array of 3He counters has been recently developed for photoneutron cross section measurements at the future ELI-NP gamma-ray beam source. We have designed a three rings geometry of 31 counters with a ˜37% efficiency flat within 5% in the 10 keV to 5 MeV neutron energy interval. A commissioning experiment was performed using proton beams delivered by the 9 MV Tandem accelerator of IFIN-HH. We measured the neutron production cross sections for proton induced reactions on nat Cu and 27Al. The (p, xn) reactions on nat Cu were investigated in the 4.5 MeV to 14 MeV proton energy range with 250 keV steps, using pulsed and continuous proton beams. The low energy measurements below 10 MeV served to validate the detection efficiency calibration against well-known natCu(p, n) cross sections. The 27Al(p, n) reaction was investigated in the 5.8 MeV to 6.75 MeV energy range with 5 keV steps. Preliminary cross section results are here compared with preceding data.

Photoneutron reactions on 208Pb in the Giant Dipole Resonance (GDR) energy range have been investigated at the γ-ray beam line of the NewSUBARU synchrotron radiation facility in Japan. Making use of quasi-monochromatic laser Compton scattering (LCS) γ-ray beams and of a novel flat-efficiency neutron detection system along with associated neutron-multiplicity sorting method, total and partial (γ,xn) photoneutron cross sections with x = 1 to 4 have been measured for 208Pb in a broad energy range covering the neutron threshold up to 38 MeV.

Prompt emission calculations for the photon induced fission of 238U and 232Th in the GDR energy region were performed by using (a) a systematic of input parameters for the most probable fragmentation approach (obtained on the basis of only spontaneous and neutron induced fission of actinides) and (b) photo-fission cross section ratios (expressing the fission probabilities at incident energies where multiple fission chances are involved) provided by nuclear reaction calculations performed with the EMPIRE code. The prompt neutron emission results describe well the experimental data recently measured at the laser Compton-scattering γ-ray source of the NewSUBARU facility, validating the use of this input parameter systematic for photon induced fission, too. The modelings and procedures described in this paper can constitute an useful tool for the prediction of prompt neutron emission data in photon induced reactions without any experimental information. [ABSTRACT FROM AUTHOR]

The well-known problem of noticeable disagreements between photoneutron cross sections from various experiments was discussed in detail for 209Bi. Data for partial photoneutron reactions cross sections obtained at Livermore (USA) using quasimonoenergetic annihilation photons and the method of neutron multiplicity sorting were analyzed using the objective physical criteria and the experimental-theoretical method for evaluation. Because of significant systematic uncertainties involved in the method for determining the neutron multiplicity, experimental data do not satisfy the criteria of reliability and differ noticeably from the evaluated data. The new experimental data for 209Bi (γ, in) reactions with i = 1–4 were obtained using quasimonochromatic laser Compton-scattering (LCS) γ-ray beams at the NewSUBARU synchrotron radiation facility and the novel technique of direct neutron-multiplicity sorting with a flat-efficiency detector. It was found that new σ(γ, 1n), σ (γ, 2n), and σ (γ, 3n) contradict noticeably to the Livermore data. It was shown that at the same time the new 209Bi photoneutron cross-sections are in good agreement with data evaluated using experimental-theoretical method and assuring the reliability of those.

The Coordinated Research Project (CRP) with the code F41032 has been launched by the International Atomic Energy Agency (IAEA) in 2016 as a 5-year project with the scientific goal being two-fold: 1) updating the 2000 photonuclear data library and 2) constructing a reference database of photon strength functions. We report the experimental technique and methodology used for the former goal and selected giant-dipole resonance (GDR) data updated in the IAEA-CRP.

We discuss the role of photoneutron reaction data in nuclear physics and astrophysics in conjunction with the Coordinated Research Project of the International Atomic Energy Agency with the code F41032 (IAEA-CRP F41032).

We discuss the γ-ray strength function toward a unified understanding of (γ,n) and (n,γ) reactions and propose a novel technique of direct neutron-multiplicity sorting to resolve the long-standing discrepancy between the Livermore and Scalya data of partial photoneutron cross sections.

Absolute cross sections for the 86Sr(α,n)89Zr reaction at energies close to the Gamow window are reported. Three thin SrF2 targets were irradiated using the 9 MV Tandem facility in IFIN-HH Bucharest that delivered α beams for the activation process. Two high-purity Germanium detectors were used to measure the induced activity of 89Zr in a low background environment. The experimental results are in very good agreement with Hauser-Feshbach statistical model calculations performed with the TALYS code.

New data of total and partial (γ,xn) cross sections with x = 1–3 are proposed to be measured by direct neutron multiplicity sorting using Laser Compton scattering (LCS) gamma ray beams at the ELI-NP to solve long standing discrepancies between existing Lawrence Livermore National Laboratory (USA) and France Centre d'Etudes Nucleaires de Saclay photonuclear data. Pioneering experiments are currently performed at the NewSUBARU facility. We present here preliminary results on 209Bi(g,xn) cross section measurements.

The Extreme Light Infrastructure - Nuclear Physics facility is dedicated to nuclear physics studies with the use of extreme electromagnetic radiation. One of the main research system to be installed and operated in the facility is an outstanding high brilliance gamma beam system. The Gamma Beam System of ELI–NP will produce intense, quasi–monochromatic gamma beams via inverse Compton scattering of short laser pulses on relativistic electron beam pulses. The gamma beams available at ELI–NP will allow for the performance of photo-nuclear reactions aiming to reveal the intimate structure of the atomic nucleus. Nuclear Resonance Fluorescence, photo-fission, photo-disintegration reactions above the particle threshold will be used to study the dipole response of nuclei, the structure of the Pygmy resonances, nuclear processes relevant for astrophysics, production and study of exotic neutron–rich nuclei.

Problem Statement: The overall objective of the work is the development of skill, we have focused on building exercises to facilitate this. Skill can be achieved by learning to accelerate and decelerate movements, or rapidly, suddenly and with the utmost efficiency of the trajectory changes of a segment or multiple body segments, while maintaining control over the body. It also develops a succession of movements in terms of execution accuracy, pace and synchronization of movements with music and movements between partners, but also learning and increasing the speed of association, unprecedented, logical and elegant combination of known motion sequences. Purpose: We believe that using rhythmic gymnastics exercises that aim at coordination, both segmental and inter-partner, we can achieve an improvement in the performance of the movements. The working hypothesis was established on the basis of the methodology of teaching rhythmic gymnastics, combined with familiar training methods. Methods: In the study we used research ascertaining. Results: One of the most beneficial forms of organizing the free time of students, and not only, is sport, and one of the most beautiful forms can be considered rhythmic gymnastics. In order to combine art with sport and to create the feeling that the competition is carried out by as many different ways as possible, I believe that the attitude of the rhythmic gymnastics in the 8th grade, which will face the capacity test, is more than beneficial. Discussion: The artistic component of these classes will play an important role in the development of aesthetic sense and in the orientation towards the beautiful, pleasant and coherent of all the activities children will continue to do in school. We need to propose and set clear objectives according to the type of lesson and the concrete tasks, so that we can use the best methods and means for the exercises to be maximized. Conclusions: In conclusion, we consider that the rhythmic gymnastics classes, which could be introduced in the extracurricular secondary school curriculum of secondary school, can bring improvements to the children of gymnasium in the sense of finding concrete means regarding the accuracy of the body movements in general but and improving ways of interpersonal communication among children. [ABSTRACT FROM AUTHOR]

The radioisotope production has a crucial role in medical diagnosis and therapy. In this work, we investigated the possibility of obtaining radioisotopes of medical interest through photo-neutron reactions using the highintensity γ beams at the Extreme Light Infrastructure - Nuclear Physics (ELI-NP) facility. The specific activity for three benchmark radioisotopes, 99Mo/99mTc, 186Re and 225Ra/225Ac, was obtained as a function of γ-beam energy, target geometry and irradiation time. Optimization for the generation of these radioisotopes at ELI-NP was investigated. We estimated that a saturation specific activity of the order of 1-2 mCi/g could be obtained for a thin target (radius 1-2 mm, thickness 1 cm) and for a conservative γ-beam flux of 1011 s-1. The ELI-NP, based on these estimations, could provide the possibility for the production of certain radioisotopes in sufficient quantities for nuclear medicine research. [ABSTRACT FROM AUTHOR]

Using \gamma -ray beams produced in the inverse Compton scattering between \CO_2 laser photons and relativistic electrons, we have calibrated electron beam energies in the nominal energy range 550–974 MeV at the synchrotron radiation facility NewSUBARU. The laser Compton-scattering (LCS) \gamma -ray beams were produced at energies from 561  to 1728 keV and detected with a high-purity germanium detector. The electron beam energies were determined by reproducing the full energy peaks of the \gamma -ray beams by Monte Carlo simulations. The accuracy of the calibration is (5.5 - 9.4) \times 10^ - 5. The reproducibility of the electron beam energy is excellent in an independent injection and deceleration. The present energy calibration of the electron beams offers a standard for the energy calibration of high-energy LCS \gamma -ray beams produced with a \Nd:YVO_4 laser. As applications of the energy calibration, we investigated the energy linearity of a 3.5^\prime\prime \times 4.0^\prime\prime \LaBr_3(\Ce) detector in the response to \gamma -rays at energies up to 10 MeV and the energy profile of the high-energy LCS \gamma -ray beams. [ABSTRACT FROM AUTHOR]