Hot Zero and Full Power Validation of PHISICS RELAP-5 Coupling

PHISICS is a reactor analysis toolkit developed over the last 3 years at the Idaho National Laboratory. It has been coupled with the reactor safety analysis code RELAP5-3D. PHISICS is aimed at providing an optimal trade off between needed computational resources (in the range of 10~100 computer processors) and accuracy. In fact, this range has been identified as the next 5 to 10 years average computational capability available to nuclear reactor design and optimization nuclear reactor cores. Detailed information about the individual modules of PHISICS can be found in [1]. An overview of the modules used in this study is given in the next subsection. Lately, the Idaho National Laboratory gained access plant data for the first cycle of a PWR, including Hot Zero Power (HZP) and Hot Full Power (HFP). This data provides the opportunity to validate the transport solver, the interpolation capability for mixed macro and micro cross section and the criticality search option of the PHISICS pack

Development of a Particle-In-Cell code with Structured Adaptive Mesh Refinement for Plasma Focus devices breakdown simulation

The aim at simulating the breakdown phase of a Plasma Focus (PF) discharge follows the need to fully understand the dynamics of such device, in order to retrieve useful information for the design and optimization of the machine itself. PFs are compact devices able to generate, accelerate, compress and confine a plasma by means of strongly varying electric and magnetic fields. In the final phase of the discharge, the generated plasma collapses in a high density region (the focus) where nuclear reactions occur. The choice of the gases composing the plasma tunes the nuclear reactions in order to characterize the device as a possible neutron-free Short-Life Radioisotopes (SLRs) generator for PET (f.i. 18F and 15O), as well as a neutrons or collimated-electrons-beams source for radio-therapy applications. An electrostatic-collisional Particle-In-Cell (PIC) code for Plasma Focus devices (es-cPIF) has already been developed to investigate the breakdown phenomenon and the formation of the plasma seed, the preliminary plasma spot, within the device: the exact knowledge of the phase space distribution function (strongly deviating from the Maxwellian equilibrium one) is a fundamental basis indeed for the whole discharge simulation. In order to extend the present simulations towards the complete evolution of the plasma seed into a running plasma sheath, the code is being re-structured for strong parallelization and inclusion of Structured Adaptive Mesh Refinement (SAMR) capabilities. In this paper the development frame as well as the software design architecture are presented together with the features that will be provided by the new SAMRes-cPIF code

Faktor Risiko yang Berpengaruh terhadap Kejadian HIV/AIDS pada Pengguna Napza Suntik (Studi Epidemiologi di Kota Pontianak)

Background: Injecting drug users (IDUs) are play role of high risk of HIV infection due to sexual behaviors that do not use condoms and use of unsterile needles. The high productive age group affected by HIV/AIDS and death, then the lower life expectancy, availability and productivity of the workforce. The purpose of the study proved that individual and environmental factors are risk factors for the incidence of HIV / AIDS among injecting drug users.Method: This observational analytic study, with the design of the case control study equipped with a qualitative approach of risk factors retrospectively. The target population of the study were IDUs in Pontianak with a sample of 96 people consisting of 48 cases of HIV/AIDS and 48 were IDUs not control HIV/AIDS. The sampling method is non-probability sampling study with consecutive sampling manner. Data analysis included univariate, bivariate using chi- square test and multivariate logistic regression test.Results: Multivariate analysis of four variables associated with the incidence of HIV/AIDSamong IDUs is married status (OR = 5,57), had sexual intercourse more than two people (OR =4,13), frequency of injecting drugs > 6 time / week yet (OR = 3,71), and not / do not work (OR= 3,28)Conclusion: Risk factors were shown to influence: the married status, had sexual intercourse more than ≥ 2 people, frequency of injecting drugs > 6 times / week and not/do not work yet

EBT2 Dosimetry of X-rays produced by the electron beam from PFMA-3, a Plasma Focus for medical applications

The electron beam emitted from the back of Plasma Focus devices is being studied as a radiation source for IORT (IntraOperative Radiation Therapy) applications. A Plasma Focus device is being developed to this aim, to be utilized as an X-ray source. The electron beam is driven to impinge on 50 {\mu}m brass foil, where conversion X-rays are generated. Measurements with gafchromic film are performed to analyse the attenuation of the X-rays beam and to predict the dose given to the culture cell in radiobiological experiments to follow.Comment: 10 pages, 14 figure

DNA damage in lens epithelial cells exposed to occupationally-relevant X-ray doses and role in cataract formation

The current framework of radiological protection of occupational exposed medical workers reduced the eye-lens equivalent dose limit from 150 to 20 mSv per year requiring an accurate dosimetric evaluation and an increase understanding of radiation induced effects on Lens cells considering the typical scenario of occupational exposed medical operators. Indeed, it is widely accepted that genomic damage of Lens epithelial cells (LEC) is a key mechanism of cataractogenesis. However, the relationship between apoptosis and cataractogenesis is still controversial. In this study biological and physical data are combined to improve the understanding of radiation induced effects on LEC. To characterize the occupational exposure of medical workers during angiographic procedures an INNOVA 4100 (General Electric Healthcare) equipment was used (scenario A). Additional experiments were conducted using a research tube (scenario B). For both scenarios, the frequencies of binucleated cells, micronuclei, p21-positive cells were assessed with different doses and dose rates. A Monte-Carlo study was conducted using a model for the photon generation with the X-ray tubes and with the Petri dishes considering the two different scenarios (A and B) to reproduce the experimental conditions and validate the irradiation setups to the cells. The simulation results have been tallied using the Monte Carlo code MCNP6. The spectral characteristics of the different X-ray beams have been estimated. All irradiated samples showed frequencies of micronuclei and p21-positive cells higher than the unirradiated controls. Differences in frequencies increased with the delivered dose measured with Gafchromic films XR-RV3. The spectrum incident on eye lens and Petri, as estimated with MCNP6, was in good agreement in the scenario A (confirming the experimental setup), while the mean energy spectrum was higher in the scenario B. Nevertheless, the response of LEC seemed mainly related to the measured absorbed dose. No effects on viability were detected. Our results support the hypothesis that apoptosis is not responsible for cataract induced by low doses of X-ray (i.e. 25 mGy) while the induction of transient p21 may interfere with the disassembly of the nuclear envelop in differentiating LEC, leading to cataract formation. Further studies are needed to better clarify the relationship we suggested between DNA damage, transient p21 induction and the inability of LEC enucleation

FENDL: A library for fusion research and applications

The Fusion Evaluated Nuclear Data Library (FENDL) is a comprehensive and validated collection of nuclear cross section data coordinated by the International Atomic Energy Agency (IAEA) Nuclear Data Section (NDS). FENDL assembles the best nuclear data for fusion applications selected from available nuclear data libraries and has been under development for decades. FENDL contains sub-libraries for incident neutron, proton, and deuteron cross sections including general purpose and activation files used for particle transport and nuclide inventory calculations. We describe the history, selection of evaluations for the various sub-libraries (neutron, proton, deuteron) with the focus on transport and reactor dosimetry applications, the processing of the nuclear data for application codes, and the development of the TENDL-2017 library which is the currently recommended activation library for FENDL. We briefly describe the IAEA IRDFF library as the recommended library for dosimetry fusion applications. We also present work on validation of the neutron sub-library using a variety of fusion relevant computational and experimental benchmarks. A variety of cross section libraries are used for the validation work including FENDL-2.1, FENDL-3.1d, FENDL-3.2, ENDF/B-VIII.0, and JEFF-3.2 with the emphasis on the FENDL libraries. The results of the experimental validation showed that the performance of FENDL-3.2b is at least as good and in most cases better than FENDL-2.1. Future work will consider improved evaluations developed by the International Nuclear Data Evaluation Network (INDEN). Additional work will be needed to investigate differences in gas production in structural materials. Covariance matrices need to be updated to support the development of fusion technology. Additional validation work for high-energy neutrons, protons and deuterons, and the activation library will be needed.Comment: 81 pages, 114 figure

Cutting-edge R&D activities of CIRTEN in support of the Technology Park annexed to the Italian National Repository of radioactive waste

R&D activities taking place at the institutions belonging to Consorzio Interuniversitario per la Ricerca TEcnologica Nucleare are here presented and discussed. A special focus is on Technology Park annexed to the Italian National Repository of radioactive waste

Plasma focus based repetitive source of fusion neutrons and hard x-rays

A plasma focus device capable of operating at 0.2 pulses per second during several minutes is used as a source of hard x-rays and fast neutrons. An experimental demonstration of the use of the neutrons emissions for radiation probing of hydrogenated substances is presented, showing a particular application in detecting water concentrations differences in the proximity of the device by elastic scattering. Moreover, the device produces ultrashort hard x-rays pulses useful for introspective images of small objects, static or in fast motion, suitable for the identification of internal submillimetric defects. Clear images of metallic objects shielded by several millimeters iron walls are shown.Comment: 15 pages, 14 figure

Studio di macchine Plasma Focus destinate alla produzione di radioisotopi per diagnostica PET e di fasci di radiazioni per terapia oncologica

Il Plasma Focus (PF) \ue8 un dispositivo in grado di generare, accelerare, comprimere e confinare in una ridotta regione di spazio un gas ionizzato allo stato di plasma. Tale plasma pu\uf2 essere portato in condizioni di densit\ue0 e temperatura sufficienti ad innescare reazioni di fusione nucleare con processi analoghi a quelli che si verificano nelle stelle. A tali reazioni consegue produzione di isotopi differenti al variare del tipo e della quantit\ue0 (in genere pochi centesimi di mole) di gas immessi in una opportuna camera da vuoto. In funzione del tipo di reazione e\u2019 poi tecnicamente possibile produrre oltre agli isotopi fasci di particelle e radiazioni. I processi coinvolti avvengono per mezzo della scarica ripetuta di un banco di condensatori a tensione relativamente alta (qualche decina di kV); tali scariche hanno durata temporale dell\u2019ordine di alcune diecine di microsecondi; all\u2019interno di tale intervallo temporale la produzione di isotopi e dei fasci di particelle annessi avviene in poche decine di nanosecondi. Tale comportamento dinamico fa s\uec che i fenomeni di produzione siano totalmente controllabili e sicuri in analogia con i tubi a raggi X e gli acceleratori oggi in uso. Tipologie di produzione: - reazioni termonucleari utili alla produzione diretta di radioisotopi a breve vita media; - neutroni veloci - fasci di elettroni relativistici - raggi X a bassa energia. Tipologie di applicazioni biomediche immediate: - produzione endogena di radioisotopi in forma gassosa per PET e, ad esempio 18F dalla reazione O16(He3,p)F18, e 15O dalla reazione N14(d,n)O15; - produzione di neutroni epitermici (<10-20 KeV) mediante rallentamento dei neutroni prodotti dalla reazione di fusione deuterio-trizio per utilizzo in BNCT (Boron Neutron Capture Therapy) per radioterapia di tumori cerebrali profondi; - produzione di neutroni termici per successiva termalizzazione per terapia col boro (BNCT) di tumori diffusi tramite autotrapianto (espianto, irraggiamento, reimpianto); - radioterapia interstiziale ed intraoperatoria per piccole masse tumorali (dimensione tipica inferiore al centimetro) tramite irraggiamento fotonico a bassa energia e ad altissimo dose-rate prodotto per ogni scarica della macchina dagli impulsi di elettroni relativistici (con energia inferiore a 1 MeV) retroemessi; la particolare tipologia del fascio consentirebbe anche di operare con tecniche ecoguidate

Magnetic quadrupole simulations for focusing the electron beams emitted by a plasma focus device

A Plasma Focus (PF) device allows for production of electron beams that, through a suitable target interaction, can be converted in X-ray pulses that have been considered for radiobiology or medical applications such as imaging or radiotherapy, in dependence from the working parameters and setup. The Plasma Focus Device for Medical Applications #3 (PFMA-3), hosted at the Montecuccolino Laboratory of the University of Bologna, has been designed for these purposes. In the device, electron pulses are generated during the pinch phase in the order of 1.0 E+15 particles in few tens of ns. One of the main advantages in dealing with the beams emitted by a PF is their self-collimated behavior at the emission time. Unfortunately, during the traveling distance from pinch to target, that collimation can be partially lost due to the repulsive interactions. One solution is to implement a magnetic device based on a quadrupoles triplet able to confine the beam in spots with a few mm diameter. This kind of focusing allows for using the PF as a source for generating extremely short X-ray pulses that could be more easily further managed for specific applications. A computational model of the PFMA-3 has been set using COMSOL© Multiphysics and the Monte Carlo MCNP6 code. The electron spectra used as source for simulations were acquired experimentally using a magnetic spectrometer, while the beam shape entering the magnetic system to be designed has been detected using Gafchromic© HDV2 film dosimeters and used as a benchmark for the numerical models. The magnetic field generated by the quadrupoles has been carefully designed through a parametric study with COMSOL© Multiphysics and the focusing effectiveness verified. The designed geometry has been then modeled in MCNP6 to perform coupled electron-photon transport simulations for estimating electron fluxes, spectra and X-ray doses as modified by the quadrupoles triplet application