Our knowledge of the states of nuclear matter under extreme conditions has advanced significantly in recent years through developments along numerous interrelated paths. This talk will describe this progress by focusing on new understanding of the densest matter in the universe, that deep inside neutron stars. Recent advances driving a better picture of neutron star interiors include...
The 1975 Nobel prize in Physics was awarded to Bohr, Mottelson, and Rainwater for the discovery of the connection between nucleon motion and the emergent collective behavior. They described nuclei geometrically as a shape and the oscillations of the nucleus around that shape. In deformed nuclei, they predicted low-lying quadrupole oscillations of the deformed shape with respect to projections...
The reaction $^7$Be(p,γ)$^8$B generates most of the high-energy neutrinos emanating from the pp-fusion chain in our Sun. Over the past twenty years there has been a substantial effort to measure its cross section at center-of-mass energies below 500 keV. One goal of this effort was accurate extrapolation of the astrophysical S-factor to solar energies. I will explain our treatment of this...
If Boron Neutron Capture Therapy is to become a practical option, accelerator-based sources of high fluxes of epithermal neutrons are essential. Generation of low energy neutron can be achieved by $^7$Li(p,n)$^7$Be reaction using accelerator-based neutron source. Much work has been performed on development of high-flux compact proton accelerators, but a doselimiting component remains design of...
The experiments at the Large Hadron Collider (LHC) at CERN are in need of major detector upgrades to cope with the increased luminosity of the High-Luminosity Upgrade of the LHC. In order to cope with the massive increases in track densities, event rates and radiation damage, the entire Inner Tracker of the ATLAS experiment will be replaced. This presentation outlines the huge challenges of...
In this work we calculated the self-shielding factor, $G$, as a function of the neutron energy, which is important to consider in precise neutron activation experiments.
Twelve samples of pure metallic materials were simulated using the Geant4 Monte Carlo toolkit[1,2] and the MCNP[3] code.
The self-shielding factor is defined as the ratio between the neutron flux inside the sample volume and...
Exclusive processes at high momentum transfer, such as Deeply Virtual Compton Scattering (DVCS) access the Generalized Parton Distributions (GPDs) of the nucleon. GPDs offer the exciting possibility of mapping the 3-D internal structure of protons and neutrons by providing a transverse image of the constituents as a function of their longitudinal momentum.
A vigorous experimental program is...
Proton-rich nuclei in the A$\sim$70 mass region relevant to the astrophysical rp-process manifest exotic structure and dynamics induced by shape coexistence and mixing, competition between like-nucleon and neutron-proton pairing correlations, as well as isospin-symmetry-breaking interactions. Recent results [1-4] concerning the interplay between isospin-symmetry-breaking and...
The evolution of the shell structure when moving away from the stability line is discussed in the present contribution. In particular, the effect of the tensor interaction in the appearance and disappearance of magic numbers and the specific case of $^{78}$Ni. To contribute to the understanding of the case, the level structure of $^{75,77}$Cu was studied in a $\beta$-delayed...
We report the generation of a pseudovector electric current having imbalanced chirality in an electron-positron strongly magnetized gas in QED. It propagates along the external applied magnetic field B as a chiral magnetic effect in QED. It is triggered by a perturbative electric field parallel to B, associated to a pseudovector longitudinal mode propagating along B. This mode is associated to...
Electronic devices are strongly influenced by radiation and the need for radiation tolerant devices is growing for applications in environments with high radiation dose [1]. The effects due to radiation on electronic components are mainly: Total Ionizing Dose (TID), Displacement Damage (DD), and Single Event Effects (SEE). TID is a cumulative effect that changes the characteristics of...
Studies of the effects of different color reconnection (CR) choices for three different models implemented in Pythia 8 event generator is shown. Validation plots for the new tunes for the three main Pythia CR model, the MPI-based scheme, the new more QCD-based and the gluon-move model are shown. Four different Rivet validated analysis are presented, the CMS_2011_S9215166 which investigates...
CDCC calculations of total fusion cross sections for reactions of the weakly bound $^{6}$Li with targets $^{28}$Si, $^{59}$Co, $^{96}$Zr, $^{144}$Sm and $^{209}$Bi at energies around the Coulomb barrier are presented. In the cluster structure frame of $^{6}$Li$\rightarrow \alpha +d$, short-range absorption potentials are considered for the interactions between the $\alpha$ and -$d$ fragments...
The production of $t\bar{t}$ pairs at high pT, i.e. the so-called boosted regime, is characterized by two collimated jets which contain most of the particles originating from the top decays. We investigate a scenario with both top quarks decaying hadronically. We attempt a definition of "top jet", by considering the substructure of the selected "fat" jets resulting from the top decay and we...
The rare-earth nuclei have well-known collective properties. The theoretical description of these nuclei represents a challenge to nuclear models, due to the enormous dimensions of the valence space, making the problem unmanageable. This leads us to use symmetry-based models, where it is possible to calculate in a free-truncation environment. In this work we present results for the energy...
Full angular distributions for the elastic scattering of the $^9$Be + $^{80}$Se system were measured at eleven bombarding energies around the Coulomb barrier namely, 17,18, 19, 20, 21, 22, 23, 24, 25, 30 and 32.8 MeV, in order to investigate the influence of the breakup of the weakly bound $^9$Be projectile on the reaction mechanisms. The $^9$Be beams were delivered by the 20 UD tandem...
A method for determination of Cr, Fe, Co, Ni, Cu, Zn, Hg and Pb in waters by Energy Dispersive X Ray Fluorescence (EDXRF) was implemented, using a radioisotopic source of $^{238}$Pu. For previous concentration was employed a procedure including a coprecipitation step with ammonium pyrrolidinedithiocarbamate (APDC) as quelant agent, the separation of the phases by filtration, the measurement of...
The FAZIA detector is a new fully digital array based on Silicon(300um)+Silicon(500um)+CsI(Tl)(10cm) telescopes. It is design to study heavy ions collisions in the Fermi energies range using a fully integrated digital electronics. Some details about the construction of this array and about the incredible performance in terms of isotopic separation will be given. Finally, some preliminary...
Spin-isospin excitations can be studied by beta decay and charge exchange reactions in mirror nuclei, shedding light on mirror symmetry, hence we can compare our results on the beta decay of proton-rich nuclei with the results of charge exchange experiments when appropriate targets for the mirror nuclei are available. Accordingly we have performed experiments at GSI and GANIL to study $T_z$...
Time of flight neutron spectrometry requires for high detection efficiency. In this work we present a detector which is based on a neutron-gamma converter ($^{10}$B disk) followed by a gamma detector (BaF$_2$). The response function to convert time of flight spectrum to energy one was constructed. About four times higher efficiency, compared to an equal thickness $^{6}$Li-doped typically-used...
A local and gauge invariant version of QCD Lagrangian is introduced. The model includes Nambu- Jona-Lasinio (NJL) terms within its action in a surprisingly renormalizable form. This occurs thanks to the presence of action terms which at first sight, look as breaking power counting renormalizability. However, those terms also modify the quark propagators, to become more decreasing than the...
The Legnaro National Laboratories have a long-standing tradition in gamma-ray spectroscopy. They hosted the most recent HPGe arrays, from GASP, one of the first Compton-shielded large HPGe array to AGATA, the first operational tracking array worldwide.
In this context, a new resident gamma-ray spectrometer GALILEO has been developed. After a 1-y long commissioning campaign, a physics campaign...
The great interest in rare earth elements (ETR) is due to the many and valuable applications that these elements have in the science and economy of many countries. On the other hand highly sensitive methods are generally required for the determination of these elements in many of the matrices of interest such as geological samples. An alternative is to apply chemical separation procedures,...
COMPASS is a modern fixed target experiment at a secondary beam of the Super Proton Synchrotron at CERN. The purpose of the experiment is the study of hadron structure and hadron spectroscopy with muon and hadron beams of high intensity. The COMPASS setup is a multipurpose universal spectrometer based on two analysing magnets and equipped with various tracking detectors, electromagnetic and...
Peloids from some Cuban spas (San Diego, Elguea, Santa Lucía, Cajío and Colony) have been studied using Instrumental Neutron Activation Analysis (INAA). Concentrations of 30 major, minor and trace elements in the peloids are reported, including an important group of REE (La, Ce, Nd, Sm. Eu, Gd, Tb, Tm and Yb). No difference is observed for metal contents (including REE) determined for raw and...
LENOS (Legnaro NeutrOn Source) project at the LNL-INFN (Italy) is a neutron irradiation facility for nuclear astrophysics studies and data validation for energy and non-energy applications. It is based on a high current low energy RFQ. The facility, will use the 5MeV, 50 mA proton beam of RFQ under test at LNL to produce an unprecedent neutron flux, precisely shaped to a Maxwell-Boltzmann...
An experimental campaign to study heavy-ion induced one- and two-nucleon transfer reactions has been performed at INFN-Laboratori Nazionali del Sud in Catania (Italy). In particular reactions induced by 18O and 20Ne beams at energies above the Coulomb barrier on different target isotopes have been explored with high resolution (both in energy and angle) and in a quite wide angular range...
In order to potentiate the experiments with Brazil Radioactive Ion Beam (RIBRAS), new VME (Versa Module Euro Card) Data Acquisition (DAQ) modules characteristics to control, triggering and data acquisition will be described. The DAQ will define to include the Strip Array and Neutron Wall detectors with maximum readout efficiency, no dead time, data selection and event synchronization.
CAEN...
Naturally occurring radioactive materials (NORM) are continuous and an unavoidable feature of life on Earth and are present in its crust since its origin. The irradiation of the human body from external terrestrial sources is mainly due to gamma rays coming from natural radionuclides, such as 40K and the elements of the series of 238U and 232Th. These primordial radionuclides present long...
I will present the low-energy light Radioactive Ion Beam (RIB) in-flight facility EXOTIC [1-4], operational at the INFN-Laboratori Nazionali di Legnaro (INFN-LNL) and the associated experimental set up [5] designed for nuclear physics and nuclear astrophysics experiments. I will present the outline of the experimental program carried out employing the produced RIBs and discuss few selected...
The LUCID-2 detector is the main online and offline luminosity provider of the ATLAS experiment. It provides over 100 different luminosity measurements from different algorithms for each of the 2808 LHC bunches. LUCID was entirely redesigned in preparation for LHC Run 2: both the detector and the electronics were upgraded in order to cope with the challenging conditions expected at the LHC...
In part I of this analysis, the striking similarities of the declining oil production in the North Sea, Indonesia and Mexico were used to model the future maximum possible oil production per annum in all larger countries and regions of the planet from 2015 to 2050.
In part II, the oil export and oil consumption patterns, that were established in recent decades, are combined with the...
Despite all the information we have accumulated during the past decades about the structure of $^{12}$C we have not resolved a number of detail, for example, the geometry of its second excited state at 7.65 MeV (0$^+$), the Hoyle-State, has not yet been solved. Recent results have showed a possible 2$^+$ resonance between 9-12 MeV that could be related with a collective rotational or...
Beta disintegration is studied in the presence of a magnetic field, which imposes a preferential direction on the emission of neutrinos. It is explored the possibility that this anisotropy in neutrino emission can account for observed Neutron (Quarks) Star velocities (kicks). The conditions under which the anisotropic emission of neutrinos (due to the magnetic field present in the system)...
During the last 6 year, the infrastructure related with Experimental Nuclear Physics at the Physics Institute, UNAM, has been benefited with an unprecedented injection of resources: four new beam lines were mounted at the CN-Accelerator Van der Graaff of 5.5 MV, which originally had just one. Moreover, a modern Tandetron AMS system of 1 MV was acquired in order to establish this kind of...
Recently the installation of a Van de Graaff accelerator in the Campus Macul of the Universidad Tecnológica Metropolitana has promoted the formation of the Laboratorio de investigación aplicada con tecnologías atomicas y nucleares (LIATAN). One of the objectives of this scientific laboratory is the development of advanced research mainly in the field of material sciences and environmental...
Our study aimed to investigate road dust from relevant locations in Havana city and the associated health risks of potentially toxic elements (PTEs) to humans using X-ray fluorescence analysis. The Geoaccumulation Index, Enrichment Factor and Integral Pollution Index were used to describe pollution characteristics of roadside dust in urban areas associated with traffic and child activities...
The SoLid experiment intends to search for active-to-sterile anti-neutrino oscillation at very short baseline from the SCK$\bullet$CEN BR2 research reactor (Mol, Belgium). A novel detector approach to measure reactor anti-neutrinos was developed based on an innovative sandwich of composite polyvynil-toluene and $^{6}$LiF:ZnS scintillators. The system is highly segmented and read out by a...
Recently, an experimental campaign was performed at the LAFN (Open Laboratory of Nuclear Physics) of the University of São Paulo. Various angular distributions were obtained at energies around the Coulomb barrier for the $^7$Li + $^{120}$Sn and $^{10,11}$B + $^{120}$Sn reactions. Besides the elastic scattering, other reaction channels, such as projectile and target-like excitation, and...
Studies on magnetic moments and life-times of exotic nuclei have unveil properties which have leaded to the deeper understanding of the nature and behavior of the nuclear potential. During last years, the alpha-transfer technique has been useful for the study of properties of nuclear species which cannot be created with the current radioactive beam facilities. One of these characteristics, the...
A novel imaging device is proposed based on the gamma-backscattering technique described in Refs. [1,2], developed at GSI (Darmstadt, Germany) and modified by the Nuclear Physics Group at National University in Bogotá, which has been successfully tested by observation of concealed objects behind metallic walls, inspection of metallic structures and localization of buried objects [3,4]. The...
We study the thermodynamical properties of a neutral vector boson gas in a constant magnetic field starting from the spectrum obtained by Proca formalism.
Bose Einstein Condensation (BEC) and magnetization are obtained, for the three and one dimensional cases, in the limit of low temperatures. In three dimensions the gas undergoes a phase transition to a usual BEC in which the critical...
Measurements of the azimuthal angle correlation between the two jets with the largest transverse momenta (pt) in inclusive 2-jet topologies, close to the back-to-back configuration, are presented for several regions of the leading jet transverse momentum. The features of the different models considered in the comparisons and their physical impact are discussed.
The spectroscopy of heavy nuclei near the $N$=152 and $N$=162 deformed shell gaps provides precious information to improve current predictions of long-lived super-heavy elements in the Island of Stability. Due to deformation, in fact, substates of spherical orbits in the island of stability can be found near the Fermi level in these lighter systems. At the JAEA-Tokai Tandem accelerator, the...
The tertiary structure and interactions with intermediate filament proteins of the desmoplakin C-terminal, a cytolinker protein related to severe skin diseases and fatal cardiovascular failures, has been determined by the use of two complementary techniques: Nuclear Magnetic Resonance (NMR) and Small Angle X-Ray Scattering (SAXS). NMR spectroscopy provided the atomic structure detail and...
The estimation of spectrosopic properties of neutron-deficient nuclei in the A=100 tin mass region is needed for the understanding of the rp-process path and the experimental exploration of the nuclear landscape. In order to evaluate some spectroscopic properties of the Gamow-Teller $\beta^+$ decay of neutron deficient tin isotopes of A=100, we have performed shell model calculations by means...
Nowadays, much attention has been given to the problem of obtaining accurate numerical solutions of fixed source discrete ordinates problems. In this work, we described and tested four different numerical methods to solve one-group unidimensional discrete ordinates problems. First, we derived the Diamond Difference (DD) method, next it´s implemented the Linear Discontinuous (LD) and Spectral...
The production of heavy clusters in nuclear reactions is a mechanism that until now is not well understood despite its importance and its wide variety of applications: radiation protection, space and engineering design, medical physics, the design of accelerators and others. According to the Exciton Cascade Model (CEM), there are three possible ways of producing high energy heavy clusters. The...
The age of sediment layers in regions near to the coast in Pinar del Rio province are determined using the quartz photoluminescence method. In some locations the studied layer could be associated with altimetry measurements allowing future analysis of recent tectonic movements. The method for sample collection, preparation and measurement are described. The results analysis indicates...
Nowadays one of the main problems of Physics is not to know the origin and nature of the acceleration of cosmic expansion during the present and future stages in the evolution of the Universe. The research carried out includes the study of a model based on the Higgs field non-minimally coupled to gravity. Cosmological implications of the Higgs field have been studied for some years, and they...
An extension to the Monte Carlo assisted Classical Method (MCCM) methodology was developed and implemented. The extension allows to calculate the atom displacement per atom (dpa) profiles considering threshold displacement energies which are spatially inhomogeneous. Calculation of the dpa profiles was performed using both, the standard methodology and extended one for gammas of 1.25, 3, 7 and...
Heavy quark $c\acute{c}$ has been studied in the non-relativistic framework using interquark potential models of the form of sum of power of the interquark distance. The form of potential is based on phenomenology facts. The proposed potential was solved numerically using a program written on C++. Mass spectra and the expectation value of the radius have been estimated for different quantum...
Employing the Feynman diagrams technique, the GBW model for performing nucleon-dipole interaction and the Regge theory, a new approach for computing in a unique way (perturbative and non-perturbative), the vector meson production has been presented.
The interaction between the color dipole created by the virtual photon and the nucleon is carried out by the exchange of two virtual gluons,...
The production of neutron-rich heavy elements takes place via the rapid neutron capture process (r-process). To favour neutron captures over beta decays the astrophysical environment should be explosive like the one found in the core-collapse supernovae. In this work, we focus on the High Entropy Winds (HEW) in Type II supernovae which are one of the more promising sites for the r-process....
The SoLid experiment aims to measure the anti-neutrino energy spectrum 6--9 m from the core of the BR2 nuclear reactor at SCK$\bullet$CEN in Mol, Belgium. The main goals are to provide a very sensitive search for short-baseline neutrino oscillations and to resolve the reactor neutrino anomaly. The proposed detector technology will be very useful for anti-neutrino detection in other settings as...
In this work, the cross sections of the nuclear reactions $^{13}$C(n, γ)$^{14}$C and $^{14}$N(n, p)$^{14}$C are experimentally measured using the accelerators mass spectrometry (AMS) technique. To carry out this experiment we use the thermal neutron flux produced by the TRIGA Mark III nuclear reactor located at the National Institute of Nuclear Research (ININ) in Mexico. The concentration of...
The natural dose rate is one of the physical magnitudes calculated during the process of age determination of geological sediments with the luminescence technique. The dose rate is calculated on the basis of the radioactive content presented in the sediments. Because of the low content of these radioactive isotopes a low background system should be used. In the present work the low background...
The gamma spectrometry is the most popular technique for the determination and quantification of the radioactive nuclei present in a radioactive source. In order to obtain the quantification of the radioactive material it is necessary to determine the efficiency of the detector for the energies of the gamma photons emitted from the source.
In the present work we present the theoretical...
In previous researches, it has been identified the presence of tetragonal and rhombohedral crystalline phases in ferroelectric ceramic samples of PbZr$_{0.53}$Ti$_{0.47}$O$_3$ doped with La (1%) (PLZT) irradiated with $^{60}$Co gamma rays, showing their corresponding XRD patterns not conclusive evidences of phase transformations between both phases assisted by gamma irradiation.
The present...
Under progressive and intensive radiation damage conditions atom displacement threshold energy, $T_d$, calculations through Molecular Dynamic Methods must take into the account, in addition to the framework of single recoil atom excitation in an ideal crystalline lattice, multiple excitations and real crystal structures with point defects, in order to reach a better approach to situations...
Present work deals with the scientific problems and the “states of arts” on regard the knowledge of the physical and structural behaviors of composite materials based on superconducting YBa$_2$Cu$_3$O$_7$ (YBCO) and carbon nanostructured compounds (wires and onnions), as well as, their electron and gamma radiation response, which are nominated as YBCO-Nano/C.
Based in the application of...
On the basis of the atomic displacement energy ($T_d$) calculated using the Density Functional Theory with Tight Binding Approximation (DFTB), the cross sections of electron-induced atomic displacement were obtained as a function of the order of the fullerene. Three types of defects commonly induced by radiation (mono-vacancy, di-vacancy and Stone-Wales) were also analyzed, determining their...
The purpose of this work was to investigate fission modes in the fission of heavy actinides. The experiments have been carried out at the U400 cyclotron at the FLNR JINR (Dubna, Russia) using the double-arm time-of-flight spectrometer CORSET. To investigate the role of closed proton and neutron shells in fission of $^{248}$Cf, $^{254}$Fm and $^{260}$No nuclei at an excitation energy of 40-45...
In this work, we have realized some spectroscopic calculations in the frame work of the nuclear shell model, in order to estimate the Gamow-teller (GT) $\beta^+$ decay of A=98 proton rich isobars in $^{100}$Sn mass region near rp-process path. The calculations are carried out by means of Oxbash nuclear structure code, taking into account the monopole effect in the studied mass region. The...
The ionizing radiation absorbed by semiconductor devices can change their properties by modifying the electrical parameters that characterize them and, in the case of memories, processors, can modify the information contained in these devices. In this way, the development of electronic devices resistant to radiation and the qualification of devices confirming that they are more tolerant to the...
For luminescence dating to be an accurate absolute dating technique it is very important that we are able to deliver absolutely known radiation doses in the laboratory. This is normally done using a beta source calibrated against an absolutely known reference source or by using a reference luminescence material that has been irradiated in a radiation calibration facility. Here we describe in...
For decades, the great economic benefit that represents the use of radiotracers has been recognized by the international industry, however, this technique is still underutilized. The main cause is the lack of timely availability of required radiotracer. Previous studies show the possibility of labeling sediments (with a high content of aluminosilicates) with $^{99m}$Tc. This paper aims to...
Semiconductor devices are susceptible to ionization radiation and this kind of event can change their behaviour and electrical properties, causing since a simple current peak on output of the circuit to a logical inversion, each event have your own root cause that can variable from an absorbed radiation dose to a different source of radiation. To deal with these problems is necessary...
The simulation of the spectroscopy systems using MC codes is a common practice in these days. The most popular softwares to do this are MCNP and Geant4 codes. In this work we present the simulation of a gamma spectroscopy system based on a coaxial HPGe detector using FLUKA code. The geometrical characterization of the detector was done from manufacturer information and using the spatial FEP...
Understanding the mechanism of energy loss of charged particles in matter is very important in atomic and nuclear physics given its application in fields such as material and surface science or radiation damage studies. In the last few years, there has been a renewed interest in increasing the accuracy of energy loss and straggling experimental values in order to determine some key parameters...
Every day, the population is exposed to various types of radiation sources. In particular, the radon is the most common radiation present in a gas form. Radon belongs to the radioactive series of uranium and in its decay emits alpha particles of 5.49 MeV. To detect these alpha particles, an effective method very commun is to use Solid State Nuclear Track Detectors (SSNTD). This work propose a...
In recent years, the investigation of spallation reactions have caught the attention of scientific community due to their application in the transmutation of nuclear waste by using the Accelerator Driven System (ADS) reactors. Due to the experimental difficulties that nuclear reactions researches face; the study of spallation reaction by using simulation codes is more suitable for generating...
The study of nuclei out of the line of stability has been one of the main fields of research in low energy nuclear physics [1]. Light exotic nuclei such as 6He, 11Be, 11Li, 8B and others are produced in laboratory [2-4] and present new interesting phenomena such as the Borromean structure and the neutron and proton halos [5]. Nuclei like 7Be [6] and 8Li are not so exotic, however, may have...
2-hydroxyethyl methacrylate/Acrylamide hydrogels were prepared by simultaneous radiation induced cross-linking copolymerization of acrylamide (AAm), 2-hydroxyethyl methacrylate (HEMA) and water mixtures at a radiation dose of 10 kGy. Hydrogesl were characterized by infrared spectroscopy. Dynamic and equilibrium swelling of hydrogels in water and in buffer solutions were investigated. They were...
Biomaterials have received a considerable attention over the last 30 years as a means of treating diseases and easing suffering. These materials have found applications in approximately 8000 different kinds of medical devices; even though biomaterials have had a pronounced impact in medical treatment, a need still exists to be able to design and develop better polymer, ceramic, and metal...
The intrinsic spatial efficiency method is a general and absolute method to determine the efficiency of any extended source. This was experimentally demonstrated and validated only for cylindrical sources and the gamma photons emitted by $^{137}$Cs (661,65 keV).
Also, we carried out a research to tested the method for different shapes and sizes. Due to the difficulty that the preparation of...
Electric Field Gradients (EFG) at Zn and O sites in disordered $^{57}$Fe doped ZnO matrixes arising from $^{57}$Mn irradiated ZnO samples with wurtzite crystal structure were simulated through DFT atomistic calculations methods. The ZnO disordered crystal defective structures were simulated by means of overdimensioned unit cells (supercell) containing Zn vacancies at different concentrations...
The objective of the experiment is to measure NORM (Naturally Occurring Radioactive Material) in natural samples and calculate their concentrations. For this purpose, experiments detecting the radiation of several gamma-ray calibration sources located at different positions around an HPGe detector were conducted. The efficiency calibration curve for each position was obtained, a piece of...
Very High Temperature Reactor (VHTR) designs of Generation IV, offer promising performance characteristics; they can provide sustainable energy, improved proliferation resistance, inherent safety, and high temperature heat supply. The 10MW High Temperature Reactor-Test Module (HTR-10) is a pebble bed reactor (PBR). To achieve the commercialization of these reactors in the nuclear industry, it...
An experimental protocol to study the total cross section for the $^{13}$C(d, p)$^{14}$C nuclear reaction via AMS is being developed for energies in the center-of-mass frame between 100 and 533 keV. We started a series of experiments in which two aluminium cathodes filled with natural-graphite (98.9$\%$ 12C, 1.1$\%$ 13C) were irradiated at a deuterium energy of 4 MeV at the 6.0 MeV Tandem...
The Monte Carlo Simulation of Atom Displacement, MCSAD, algorithm and code have been developed and applied in solid materials for the assessment of electron and gamma radiation damage. In the code, single primary knock-on atom (PKA), processes are taken into account in regard to atom displacement (AD) occurrences, which give a well-suited description of radiation damage effects on relative low...
In OSL dating of sediments the application of the single aliquot regenerative (SAR) protocol requires the calibration of each aliquot by giving them a known dose using an internal beta source with a dose rate ranging from 100 to 30 mGy/s. In the case of old samples that have received in natural conditions doses higher than 70 Gy the time employed to equate this dose may be significant. One...
SPES (Selective Production of Exotic Species) is the INFN project for a Nuclear Physics facility with Radioactive Ion Beams (RIBs). It is in advanced construction in Legnaro, with several technological innovations and challenges foreseen, comprehensive of new achievements and improvements.
SPES will provide mostly neutron-rich exotic beams derived by the fission fragments (1013 fiss/s)...
An significant part of the upgrade of the Dubna Radiactive Ion Beams facility is the replacement of the ACCULINNA fragment separator with a new high acceptance device - the ACCULINNA-2. The project of a new in-flight facility for low energy 30-60 AMeV primary beams with 3 ≤ Z ≤ 36 has been started in 2011. The new device is destined to add considerably to the studies of drip-line nuclei...
The “Radioactive Ion Beams in Brasil” (RIBRAS) facility is the first device in the Southern Hemisphere to produce unstable secondary beams. It is in operation since 2004 and it consists of two super-conducting solenoids of maximum magnetic field B = 6.5T, coupled to the 8UD-Pelletron tandem Accelerator installed at the University of São Paulo Physics Institute. The radioactive ions produced by...
Overarching questions such how and where are the heavy elements synthesized, and what is the mechanism of stellar explosions, like supernovae, have been the subject of study of nuclear astrophysics for the last decades. These puzzles are closely connected to the behavior of matter under extreme density and temperature conditions. Our current understanding relies on simulations, micro-physics...
Scientific investigations in the cultural heritage and objects of art are routinely performed in Europe and the United States a few decades ago, in Brazil we are currently increasingly using atomic and nuclear methods for this purpose. Since 2003 the Group of Applied Physics with accelerators of the Institute of Physics of the University of São Paulo has worked with various methodologies for...
For the fisrt time, a Saliba's painting was investigated by means analytical technique, MA-XRF (Macro- X-Ray Fluorescence). The LANDIS-X, a novel mobile scanner, allowed to obtain elemental distribution of the pigments allowing better elucidating palette and painting technique.
Nowadays, the experiments related to the High Energy Physics and others fields demand the use of detectors with greater radiation resistance, and the novel material GaAs:Cr had demonstrated excellent radiation hardness compared with other semiconductors. On the basis of the evidences obtained in the JINR experiment with the use of 22 MeV electrons beam generated by the LINAC-800 accelerator,...
In this work we calculated two kinetic parameters of the RECH-$1$ research nuclear reactor: the effective delayed neutrons fraction, $\beta_{eff}$, and the mean neutron generation time $\Lambda$ using the Monte Carlo codes MCNP6 [1] and Serpent 2 [2] and the neutron cross section library ENDFV.VII.$1$.
To calculate $\beta_{eff}$ we used the method proposed by Meulekamp and van der Marck[3]. In...
In this work the characterization of a multichannel analyzer conceived in the CEADEN and developed on the basis of an FPGA, is presented. The system consists of 2048 channels; 32 000 counts per channel at most; 4.5ns of sampling time and a dead time of 16ns. A differential non-linearity (DNL) of +3.62 ± 1.56 and a non-integral linearity (INL) of +0.29 ± 0.05, in addition with the increase of...
Nowadays, the use of Aqueous Homogeneous Reactors (AHR) for the production of medical isotopes, mainly 99Mo, is potentially advantageous because of their low cost, small critical mass, inherent passive safety, and simplified fuel handling, processing and purification characteristics. However, it faces some challenges to be successfully deployed for the production of medical isotopes. This...
The service provided by the Gamma Cameras (GC) in the nuclear medicine departments fails because of their breakdown, generally due to the associated electronics and not to the physical detection components. For this reason, it was decided to develop an electronic system that allows the recovery and optimization of disused GC, starting with the design of the preamplifier for each...
Experimental angular distributions for the $^{7}$Li + $^{120}$Sn elastic and inelastic (projectile and target excitations) scattering, and for the neutron stripping reaction, have been obtained at $E_{{\rm LAB}}=$ 20, 22, 24 and 26 MeV, covering an energy range around the Coulomb barrier ($V_{B}^{{\rm(LAB)}}\approx21.4$ MeV). Coupled channel and coupled reaction channel calculations were...
The advanced GaAs:Cr material for radiation detection is in the scope of many scientific and technological institutions in the world, as consequences of its proved superior properties and economic advantages. Experiments made at the JINR Dzhelepov Laboratory of Nuclear Problems for the energy calibration of a hybrid GaAs:Cr-based Timepix detector with alpha particles reaffirm that this device...
This paper describes the development of an instrument for Radiological Monitoring and Gamma Alarm (GAMAL01). It monitors the burst of radiation produced during a radioactive accident and triggers an alarm for evacuation in case the radiation exceeds an established threshold. The instrument consists of two sections, analog and digital.
Key words: Geiger Müller counters, data acquisition...
Positron emission tomography (PET) is one of the most important diagnostic tools in medicine, allowing three-dimensional imaging of functional processes in the body. It is based on a detection of two gamma rays with an energy of 511 keV originating from the point of annihilation of the positron emitted by a radio-labeled agent. By measuring the difference of the arrival times of both...
The chromium - compensated gallium arsenide is attaining a relevant position between the materials devoted to the development and fabrication of radiation detectors. This material shows high resistance to the radiation damage, high effective Z, relative low production cost, possibility to grow large area films, etc. Some results from the study of Timepix hybrid detectors based on GaAs:Cr by...
Giant-dipole- resonance photoneutrons (GRN) are produced by LINAC 2300 CX operating in the range of 15 MV. During radiotherapy treatment unwanted neutron dose is delivered to patients. To establish the thermal and epithermal photo-neutrons field during radiotherapy treatments Nuclear Track Methodology (NTM). The well tested polyallyldiclogola carbonate (PADC type CR-39 TM on that a thin boron...
Spherically symmetric solutions are presented of the equations of motion for a scalar field interacting with gravity (EKG equations) in the Colombeau-Egorov’s sense. The scalar fields are confined within the interior region and the exterior fields are purely gravitational and coinciding with the Schwarzschild ones. The solution resembles the so called ”gravastars” which had been discussed in...
High resistivity gallium arsenide compensated by chromium has demonstrated a good suitability as a sensor material for hybrid pixel detectors used in X-ray imaging systems with photon energies up to 60 keV. The material is available with thickness up to 1 mm and thanks to its Z number and fully active volume of the sensor high absorption efficiency in this energy region is provided. Although...
In recent years, CT has proven itself as a method of nondestructive research in biology, geology, industry, and other fields. However, until recently, the detectors used in CT recorded only the intensity of the radiation, losing information about the energy. The method of dual-energy CT partially corrects this deficiency. With the advent of hybrid matrix detectors with the single photon...
Among the most modern ionizing radiation detectors, the hybrid based on GaAs:Cr Timepix stands out as one of the most competitive due to its characteristics, such as its high Z and its strong resistance to radiational damage. In addition to their use in high energy physics research, they have been effectively employed in the medical visualization, spatial technologies, geological prospecting,...
The High Performance Light Water Reactor is one of the most promising concepts of the Fourth-Generation reactors. Uranium mono nitride (UN) and Uranium mono carbide (UC) as nuclear fuel alternative for the HPLWR, offer the advantage of high thermal conductivity as compared to UO$_2$. The use of coating can solve the problems of the reactive nature for UN and UC which arise when these fuels are...
The Generation IV Very High Temperature Reactor (VHTR) is envisioned as an outstanding prototype among the six nuclear systems propose in the Generation IV. The characteristics that highlights this reactor are focused in the low electricity generation costs, short construction periods, in proliferation resistance and physical protection. Nevertheless, it presents essential challenges to be...
Carbon nanostructures, obtained by underwater arc discharge of graphite electrodes, were studied by X-Ray Photoelectron Spectroscopy (XPS). It was observed that the spectra of the samples taken from the floating part of the synthesis products, composed basically by Carbon nano-onions (CNO), present differences with those obtained from the precipitate , which contains a mixture of CNOs and...
Nuclear reactions induced by neutron-rich radioactive beams have opened new possibilities for studying nuclei far from stability line [1]. The increase of the reaction cross-sections for neutron rich nuclei compared to the stable nuclei can be attributed to their larger nuclear radii. In order to observe this effect a systematic investigation of total reaction cross sections from elastic...
We demonstrated in previous investigations that the internal structure of paintings can be visualized with conventional radiography in transmission mode when paintings have the proper stratigraphy. Unfortunately, there are many paintings that do not result in useful images. This problem can be solved by using radiography in emission mode. With this technique, the painting is irradiated with...
We use Hartle's formalism to study the effects of rotation in the structure of magnetized white dwarfs within the framework of general relativity. The inner matter is described by means of an equation of state for electrons under the action of a constant magnetic field, which breaks the SO(3) symmetry and introduces a splitting of the pressure into one parallel and other perpendicular to the...
Heavy ion nuclear reaction studies are an important tool to observe and disentangle different and competing mechanisms, which may arise in the different energy regimes. In particular, at relatively low bombarding energy the comparison between pre-equilibrium and thermal emission of light charged particles from hot nuclei is interesting. Indeed, nuclear structure of the interacting partners and...
Attenuation of hadrons with open or hidden heavy flavor, produced in relativistic heavy ion collisions, is described within the color-dipole approach. A charmonium propagating through a dense matter can be broken-up by either Debye screening of the binding potential (melting), or due to color-exchange interactions with the surrounding medium (absorption). These two effects are found to have...
During the last two decades, the Nuclear Physics Group of National University (GFNUN) has been leading nuclear basic research, generating innovation edge based on its own basic research, training researchers, public servers and society, and building technological transfer. The nuclear Colombian context presents a weakness on strategical nuclear programs and politics based on technical...
Air quality models are an important tool to assess the responsibility for existing air pollution levels through the evaluation of source-receptor relationships. Back trajectories have frequently been used to identify potential source areas of air pollutants and to clarify their respective contribution at receptor sites.
CALMET/CALPUFF modelling system is well known, and several validation...
Slags are final by-products involved in the iron and steelmaking process. The general tendency in the foundry workshops in Cuba is to consider slag as a waste material and deposit it in the yards of the workshops or in municipal landfills affecting the environment. Its composition and characteristics depend and vary widely according to the raw material used, the technology employed and the...
The objective of this work was to evaluate the exposure levels to PM10 to which workers are exposed during the working day. Sampling was carried out in two workplace areas of a factory located in Santa Clara city: the iron casting workshop and the unmolding workshop. The factory utilizes as raw materials: iron scrap, ferroalloys, coke, and materials from the own process as pig iron and return...
One of the nuclear techniques that are being investigated by different groups in the field of explosives detection and demining is the thermal Neutron Backscattering Technique (NBT). NBT is based on the fact that the buried target is Hydrogen-rich and therefore if it is in a media with different Hydrogen content and it is exposed to a fast neutron source, the number of backscattered thermal...
Tri-structural Isotropic (TRISO) based fuel with SiC matrix can be used in Light Water Reactors (LWRs) for enhancing its safety features in extreme situations. Besides the simplification of the design, the utilization of TRISO fuel particles in PWR technology enhances its integrity by confining the radioactive fission products within fuel itself during the reactor operation. In this work, the...
Building on the success of the large nuclear plants, SMRs offer the potential to expand the use of clean, reliable nuclear energy to a broad range of customers and energy applications. In this work, a model to describe the neutronics parameters of a SMR core that can produce up to 530 MW of thermal power was developed. Using this model, several configurations of fuel enrichment to obtain the...
In this work, several oil samples from different Brazilian basins were investigated using Energy Dispersive X-Ray Fluorescence spectroscopy technique (ED-XRF) aiming to obtain qualitative information about their chemical composition [1,2]. The budget of analyzed samples was composed of twelve oil samples from five distinct oil fields belonging to the Campos Basin of the Esp ́ırito Santo and to...
The present work presents a procedure designed for the improvement of the Quality Management System (QMS) implemented in the laboratories of Chemical Analysis and Materials of the CEADEN according to NC ISO / IEC 17025: 2006 in order to allow a stability in time of their status as accredited laboratories. In these laboratories, nuclear and complementary techniques are used in research and...
Radioactivity levels in peloids from some Cuban spas (San Diego, Elguea, Santa Lucía and Cajío) have been studied. The radionuclide concentration (in Bq.kg-1 dry weight) varied as follows: $^{226}$Ra = 6 – 1800, $^{137}$Cs = <2 – 5, $^{232}$Th = 6 – 38 and $^{40}$K = 47 – 365, being comparable to concentrations reported for therapeutic peloids used worldwide. Considering the short exposition...
The regional offset correction ΔR of Marine Reservoir Effect (MRE), crucial for correcting $^{14}$C ages calibration for marine influenced samples, was determined for Cuban Northwest coast. Fifteen different locations were studied by $^{14}$C dating of pre-bomb known-age marine shells specimens of bivalves and gastropods from the Felipe Poey Museum collection. The distribution of results...
The application of the method of radioactive indicators in research and development of drugs is of great importance for the pharmaceutical industry. Many non-clinical and clinical trials rely on the radiolabelling of the molecules being tested as potential drugs. In the present investigation, a preliminary computational model was developed to obtain the possible structures of the CIGB-300...
Concentrations of various chemical elements in street dusts from Camagüey city were studied by X-ray fluorescence analysis. The mean Cr, Co, Ni, Cu, Zn and Pb contents (in mg.kg$^{-1}$ dry weight) in the urban dust samples were compared with mean concentrations in other cities around the world. Spatial distribution maps indicated the same behaviour for Cr–Ni and Pb–Zn–Cu, whereas the spatial...
As part of the instrumentation development program of the luminescence dating laboratory at CEADEN a package of open-source software supporting the luminescence measuring process is carried out. The package released under the name of Sequence-Toolkit is routinely used to create and analyze the results of the measuring sequences introduced to the automated luminescence reader LF02. Here we...
Rhenium bis-arenes can be obtained by heating the corresponding potassium perrhenate (KReO$_4$) salt with an arene as a solvent and in the presence of aluminum chloride (AlCl$_3$) and zinc. Variations of this method, originally proposed by Fischer and Hafner, demonstrated that, in some cases, the reaction occurs without using Zn as a reductive agent, but also, that the presence of the Lewis...
The losartan and its fluoro n-ethoxy-methyl-triazole losartan derivatives (FEM, n=0-3) were studied as potential candidates of $^{18}$F-labeled radiopharmaceuticals. Each derivate is obtained by the reaction of a terminal alkyne with a substituted azide in presence of Cu(I) catalyst. The stability and association energy of four FEM to the AT1 receptor was evaluated. The Density Functional...
The objective of the present study was to evaluate the distribution and accumulation of some heavy metals in surface sediments from the Mamposton reservoir (Mayabeque province, Cuba) and its main tributaries (Ganuza and Mamposton rivers and Pedroso dam). Furthermore, it was of great interest to assess their potential risk with regard to human health. Concentrations of Fe, Ni, Cu, Zn and Pb...
Fusion reaction play a critical role in stellar evolution and nucleosynthesis [1]. However, the important fusion reaction still carry large uncertainties at Gamow region due to the low cross sections and, the limited theoretical understanding on the mechanisms related to the fluctuations that occur in the cross section [2]. Recently, we investigated $^{12}$C+$^{12}$C system, by making use of...
In the last decades, a renewed attention to clustering in nuclei has emerged due to the study of weakly bound nuclei at the drip lines [1]. Clusters in nuclear systems can be related to their dynamical formation or their structural presence (pre-formation) in nuclei. While for light nuclei several links between cluster emission and its connection with nuclear structure and dynamics have been...
Five years ago, particle physicists announced the discovery of the Higgs boson, the last missing ingredient in the Standard Model.
Since then, the enormous wealth of data collected by the ATLAS experiment has allowed us to zoom in on the properties of this fundamental scalar that is linked to electroweak symmetry breaking, a fundamental ingredient in the model that describes the elementary...
The ALICE experiment at CERN investigates the properties of strongly interacting matter at high temperatures. This talk highlights some of the recent results from the collaboration,presenting key constraints on properties of the QCD matter. A brief description of the ALICE upgrade program is also given.
In the Run-2 of the Large Hadron Collider, CMS is recording an impressive amount of proton-proton collision data at a center of mass energy of 13 TeV. In this talk, we highlight the CMS status in 2017 and some of the latest physics results.
The Mu2e Experiment at Fermilab will search for coherent, neutrino-less conversion of negative muons into electrons in the field of an Aluminum nucleus. The dynamics of such charged lepton flavour violating (CLFV) process is well modelled by a two-body decay, resulting in a mono-energetic electron with an energy slightly below the muon rest mass.
If no events are observed in three years of...
The results of the Q-weak experiment at the Thomas Jefferson National Accelerator Facility are presented. The experiment performed the most precise measurement of the parity-violating electron-proton scattering asymmetry at low momentum transfer, resulting in the first direct determination of the weak charge of the proton (a weak force analog to the electric charge for the electromagnetic...
GRIFFIN [1], the Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei is the new decay spectroscopy array located at TRIUMF, Canada’s National Laboratory for Nuclear and Particle Physics. GRIFFIN consists of 16 large-volume hyper-pure germanium clover detectors assisted by a custom-built digital data acquisition system, providing 10% efficiency for detecting gamma-rays at 1.3 MeV....
Lima, the capital of Peru, and Callao, an urban region, form on of the largest urban centers in South America, with a total population of 10,9 million as of 2017. Three rivers supply water to the capital, however, water for municipal use is mainly taken from the Rimac and Chillon River. The estimated water availability is 148 m$^3$/person/year, well below the limit of 1000 m$^3$/person/year...
Nucleosynthetic processes in supernovae and X-ray bursts often involve unstable ions and reactions that are difficult to produce at the relevant energies in rare beam facilities. Recent progress in astronomical observations and the chemical evolution of the Galaxy need to be accompanied with similar progress in understanding the relevant properties of rare isotopes through nuclear physics...
Gamma-ray Compton backscattering has proven to be of interest for technical applications, one example being an imaging device [1] able of getting the shape of objects behind material obstacles. A big deal of work has been performed in order to characterize the process, which, given the huge mathematical difficulties of an intrinsically random, non-lineal process, numerical simulation is...
The international ISOL facility ALTO, located at Orsay in France, provides stable ion beams based on a 15 MV tandem accelerator and neutron-rich radioactive ion beams from the interaction of a γ-flux induced by a 50 MeV 10 µA electron beam in a uranium carbide target. New setups are under preparation to extend the fundamental properties measured at ALTO of ground and excited states of exotic...
This work presents the results obtained during the hydrochemical and isotopic characterization of the waters of the Mampostón - Jaruco basin in the province of Mayabeque, Cuba. Two sampling campaigns were carried out in different wells drilled in the area, carrying out the collection of hydrochemical data in the field, the analysis of macrocomponents and physico-chemical parameters in the...
NUMEN proposes cross sections measurements of Heavy-Ion double charge exchange reactions as an innovative tool to access the nuclear matrix elements, entering the expression of the life time of Neutrinoless double beta decay (0νββ). If detected, such a process would give direct evidence to the Majorana-nature of neutrinos, opening a window to physics beyond the standard model.
A key aspect of...
Concerning thermal neutron induced fission of uranium 233, using a Monte Carlo simulation, we show how prompt neutron emission from fragments distorts the distribution of charge as a function of final mass and kinetic energy compared with the primary distribution. Since fission discovery, the yield of primary charge (Z), mass (A) and kinetic energy (E), has been one of the objectives of...
With the aim of studying the evolution of nuclear shells in the region of neutron-rich Sn isotopes, the MagicTin project (EU-MSCA 661777) will exploit the capabilities of the ACTAR TPC detector for measuring direct reactions in the Z≥50, A≥132 mass region.
In preparation for these experimental campaigns, to be done at the forthcoming radioactive ion beam facilities like SPES, HIE-ISOLDE or...
The present work deals with the numerical simulation of gamma and electron radiation damage processes under high brightness and radiation particle fluency on regard to two new radiation induced atom displacement processes, which concern with both, the Monte Carlo Method based numerical simulation of the occurrence of atom displacement process as a result of gamma and electron interactions and...
Double beta decay (DBD) is a nuclear process with the longest lifetime measured until present, which study presents a great interest. Indeed, its possible neutrinoless double beta (0νββ) decay mode is a beyond Standard Model (BSM) process whose discovery would clarify if the lepton number is conserved, decide on the neutrinos character (are they Dirac or Majorana particles?) and give a hint on...
I will report on a quantitative study of the sub-Coulomb fusion of astrophysically important heavy-ion collisions, such as $^{16}$O + $^{16}$O and $^{12}$C + $^{12}$C. It is carried out using wave-packet dynamics. The low-energy collision is described in the rotating center-of-mass frame within a nuclear molecular picture [1]. A collective Hamiltonian drives the time propagation of the...
Nuclear structure far from stability plays a crucial role in the processes that lead to the formation of the elements. In the specific case of the proton drip-line, its location constrains the path of nucleosynthesis in explosive astrophysical scenarios such as in supernovae and X-ray bursters.
In such scenarios, the density and temperature are so high, that rapid proton capture can occur, and...
Measurements in nuclear β decay played a crucial role in the development of the (V-A) theory of weak interactions, which is embedded in the standard electroweak model (SM). Experiments in β decay offer today a sensitive tool to search for physics beyond the SM, complementary to direct searches performed at high energies.
It has recently been observed that, in searches for new interactions and...
The accurate measurement of the baryon density by WMAP renders Big Bang Nucleosynthesis (BBN) a parameter free theory with only inputs from measurements of the relevant (12 canonical) nuclear reactions. BBN predicts with high accuracy the measured abundance of deuterium, helion and helium relative to hydrogen, but it over-predicts the abundance of 7Li relative to hydrogen by a factor of...
The EMC effect is the observation that the structure of nucleons in nuclear medium is modified from that in free space. Over 1000 papers were written about the effect, but no explanation is commonly accepted. A linear correlation has recently been observed between the slopes of the EMC universal curve for 0.3 < x$_B$ < 0.7 in deep-inelastic (DIS) lepton scattering, d[F$_2$(A)/F$_2$(d)]/dx$_B$...
Transition strengths in the Ni isotopes between N=40 and N=50 have been recently subject of extensive experimental and theoretical investigations, aiming to understand whether the tensor forces act to reduce the Z=28 shell closure as the neutron g9/2 orbit is filled towards 78Ni.
The effect of the Z=28 shell gap quenching and its evolution from 68Ni towards 78Ni would be reflected as an...
The present experimental study on $^{77}$Cu has been carried out at Radioactive Ion Beam Factory of the RIKEN Nishina Center. It will complement the previous study of $^{77}$Cu via beta decay of $^{77}$Ni where the low-lying states in $^{77}$Cu were identified as particle-core excitations through the comparison to the large scale Monte Carlo Shell Model calculations (E. Sahin et al. ...
Recently, a new high-energy (up to 70 MeV) and high-intensity cyclotron has been installed at the INFN-LNL National Laboratories of Legnaro (Padova, Italy). This facility will be soon put in operation and one of its research goals will focus on the production of radioisotopes for medicine and, in particular, theranostics, in the context of the INFN LARAMED initiative.
As research group, we are...
Optimization of chest radiography aims to ensure that image quality remains adequate for the clinical tasks undertaken, while patient exposure is kept as low as possible. Establishing good image quality is a complex subject as this is strongly linked to clinical task. Additionally, the evaluation of a large number of system parameters is necessary. While clinical trials offer the gold standard...
The purpose of this work was to revise how well XiO treatment planning system (TPS 4.80 patch 03) Intensity Modulated Radiation Treatment (IMRT) calculations are delivered by an Elekta Synergy Platform-MLCi2 machine using Task Group 119 (TG119) benchmarked data of the American Association of Physicists in Medicine (AAPM) in order to implement future IMRT treatments at the Radiotherapy Center...
The methodology of Risk Matrices has been used extensively for safety assessments in the risk industry. The method characterized by being systematic and simple, features that allow considering its application in hospitals. The practice of radiotherapy, where fatal accidents have occurred, needs to apply methodologies to anticipate and prevent potential accidents. The Ibero-American Forum of...
Among the most used methods of risk analysis for medical practices with ionizing radiations are the Risk Matrix and the Failures Modes and Effects Analysis. Two large projects represent these methods. The first corresponds to the Forum of Radiological and Nuclear Regulatory Agencies (FORO-IAEA) and the second to the TG-100, of the American Association of Medical Physicists (AAPM). The...
Mammography is the gold standard to diagnose breast anomalies at the present; nevertheless, the automatized methods using PC interface are increasing today. They help physicians to give a Breast Imaging Reporting and Data System (BIRADS) classification.
The comparison of some automated methods is presented in this work to detect breast anomalies with good sensibility and specificity on PC,...
Electrons generated by photons during their interaction with matter produce significant ionization through electron-electron Coulomb interactions along their track. The absorbed dose deposited along these tracks is defined as the product of the electron fluence generated and the linear energy transfer, LET, or the restricted mass stopping power averaged over the electron energy spectrum....
Background: Independent external audits play an important role in quality assurance in radiation oncology, for this reason the International Atomic Energy Agency (IAEA), in its technical document IAEA-TECDOC-1583, recommends a procedure to establish quality assurance of Radiotherapy Planning System (RTPS) using the IMRT Thorax Phantom (CIRS - 002LFC). The procedure is based on an anatomical...
Currently at our centre, the stereotactic program uses 6 MV cFF and forward planning techniques: cones for SRS, conformal MLC for SRT. Patients are immobilized with either the non-invasive Aktina stereotactic frame or a thermoplastic mask. Treatment localization is performed with CBCT. We are implementing DCAT and VMAT for SRT with 6 MV FFF to reduce treatment time, treat larger non-spherical...
This study provides dosimetric data from the commissioning of two Sensus SRT-100 50–100 kV X-ray units. Data collected during the commissioning process included: a) HVL, b) output (dose rate), c) applicator cone factors, and d) profiles. Percentages depth dose were not measured due to lack of resources. Farmer-type chambers (iba-FC65-G), and a thin-window parallel plate ion chamber...
Several Monte Carlo (MC) codes are available for performing radiotherapy dose calculations, with acceptable accuracy. The objective of this work is to analyze the differences in the calculations obtained by different MC codes and their impact on the absorbed dose evaluations. In order to evaluate the possible systematic differences, a comparison was made between different electromagnetic...
Relative renal function and differences in the images of kidneys through renal gammagraphy with radiopharmaceutical $^{99m}$Tc-MAG3 and $^{99m}$Tc-DMSA was compared. For the study a sample of 50 patients was analyzed, in which 75% were children. Images were acquired with a double-headed AnyScan SC gamma camera of MEDISO Company. The renal gammagraphy with $^{99m}$Tc-MAG3 was processed as a...
Since its discovery in 1935 by J. Chadwick, neutrons have been used in many fields, from power production to medical applications. In particular, G. L. Locher in 1936 came out with the idea of using neutron capture for cancer treatments. Currently the Neutron Capture Therapy (NCT) stands for a binary treatment method that combines a cancer specific Boron ($^{10}$B) or Gadolinium ($^{157}$Gd)...
After the discovery of neutrons, G. L. Locher proposed the idea of using neutron capture for cancer treatment - Neutron Capture Therapy (NCT). This treatment method combines either a Boron ($^{10}$B) or Gadolinium ($^{157}$Gd) labeled drug and an epithermal neutron beam suitable for neutron capture to take place within the treated tissues. With a branching ratio of approximately 94%, the...
In the last decades the use of the Human Amniotic Membrane (HAM) in regenerative and curative medicine has been significantly increased. The sterilization processes of the HAM are crucial for its clinical use. In order to preserve the main biophysical and biochemical properties of HAM, improvements are required in the sterilization procedures, in which some of the valuable HAM's properties are...
In medical physics, conventional machine learning uses “hand designed” feature extractors which require great domain expertise. Deep learning has dramatically improved state-of-the-art machine learning in a variety of domains - including speech recognition, visual object recognition, and object detection. Deep learning networks do not need “hand designed” features, but they usually require...
This work presents an integral description of electron beam deflection control as required for novel radiotherapy technique based on convergent photon beam production [1,2]. Conventional radiotherapy is mainly applied by linear accelerators. Although linear accelerators provide dual (electron/photon) radiation beam modalities, both of them are intrinsically produced by a megavoltage electron...
It is recognised worldwide that the security of radioactive materials is very important and that the design of facilities where these sources are used and stored must cater for the implementation of good security measures, including the shielding of some treatment and diagnostic rooms. The radiation protection assessment of a nuclear medicine facility consists of the evaluation of the annual...
Was designed and produced a cylindrical phantom in PMMA material for evaluate the image quality parameters: spatial resolution, high and low contrast, magnification, uniformity and reproducibility of Hounsfield numbers for Computed Tomography (CT) through the formation of images in the acquisition of tomographic images. The phantom was designed and built under the recommendations of...
The $^{85}$Kr isotope is a beta-ray emitter (gas) with a half-life of 10.76 years. It is produced in the fission of Uranium and Plutonium. The sources of this isotope are the nuclear tests, the nuclear reactors and the reprocessing of nuclear fuel. In the gas release events around reactors, the $^{85}$Kr may represent a major hazard. In beta emitters, in order to evaluate the absorbed dose...
The massive development of photon radiation treatment techniques as well as the increase use of Hadron therapy has led to a difficult treatment evaluation since many parameters are in play. At the same time, there has been an increase of cancer clinical data generation in the form of clinical records and imaging data. As a response, biophysical models based on clinical data mining and machine...
14F7 is a murine monoclonal antibody that recognizes the ganglioside N-Glycolil GM3 and induces death in tumor cells that overexpress this ligand. Antibody fragments exhibit improved pharmacokinetic properties as compared to whole antibodies. The study was based on two assumptions: first, the h14F7-F(ab')$_2$ does not lose its biological activity; second, labelled with $^{99m}$Tc, have a more...
In this work the study of the Deposited Dose Distributions in depth by Protons and Carbon Ions in different Phantoms, was made with Monte Carlo Method. Initially, a simulation of the interaction of the charged particles (Protons and Carbon Ions) with water was constructed with the Geant4 tool (Fig.1.). The Bragg peaks and Deposited Dose Maps at multiple energies within the therapeutic range...
In lung cancer, SBRT is used to deliver high doses to a small dense GTV moving into a low-density tissue (margin generating the PTV). If IMRT or VMAT are used to treat such inhomogeneous PTV, a homogeneous dose distribution is achieved generating high photon fluence inside a 3D shell (PTV-GTV). Paradoxically the dose distribution is apparently uniform, but the GTV, which moves into the PTV,...
During more than 60 years of Hyperthyroidism radioiodine treatment has been no general agreement on the applied dose or calculus methodology. The EANM Dosimetry Committee recommend in 2013 an “Standard Operational Procedures for Pre-Therapeutic Dosimetry (SOP)” based on the assessment of the individual $^{131}$I uptake and kinetics. To estimate the 3D dose delivery deviations from prescribed...
The availability of tools for visualize, control, and track patient specific respiratory motion could improve the accuracy in radiation therapy for thorax and abdomen tumor lesion. If smaller treatment fields are used, there is the possibility of target may move out of the treatment field resulting in an under dose to the target and surrounding normal will be exposed.The goal of this work is...
There is sufficient information in vitro and in vivo that indicates that AT1 receptor (part of the blood pressure regulated system Renin-Angiotensin) is overexpressed in malignant tumor. The losartan is one of the most studied antagonist of this receptor, for that reason, this study evaluated the fluoro-alkyl losartan-derivatives ($^{18}$FAL) as potential candidates of $^{18}$F-labeled...
Very soon is going to work in Cardiological Center of Villa Clara, Cuba, a new brand of X ray Device, (that is X Ray in C Arm), that includes electrophysiology functions, in which the irradiation time might be longer in comparison with Hemodynamic Machines and interventionist cardiology, where take place several procedures of less duration such as angiographies and angioplasties. It is shown...
This research, propose a monitoring procedure of $^{131}$I intake of nuclear medicine workers using the thyroid probe of the Nuclear Medicine Department. The Thyroid Counter used is a gamma probe, equipped with a lead shielded NaI(Tl) scintillation detector of 30x30, also was studied the gamma camera Phillips Forte with NaI(Tl) 3/8" pinhole collimator-5mm. The efficiency calibration was...
Intra-Operative radiotherapy (IORT) is a very effective technique that has begun to be used in our region. It has proven to be a good alternative as part of the breast conserving surgery. Technical success is based on the administration of high doses to the lesion in a single treatment session of radiotherapy, during the same surgical operation, with multiple clinical advantages that are not...
The optimization of patient-specific treatment planning of hyperthyroidism with $^{131}$I is a desirable goal from medical and radiation protection point of view. The purpose of this work was to develop a software based on MATLAB, capable to handle non-uniform activity distribution at voxel level and made dosimetry calculation using the “S” factor from MIRD methodology, planning the...
Total Body Irradiation (TBI) is a radiotherapy technique that consists of irradiating homogeneously the whole patients body and it is characterized by extended source to surface distances and the use of large irradiation fields. The limitations of the available input data and inherent problems with the calculation procedures make it very difficult to accurately determine the dose distributions...
In radiotherapy and nuclear medicine processes, medical physic have a preponderant participation in the correct administration of prescript doses to a patient, so that if they differ more than a predetermined value to the prescription, become in radiological accident or a mistreatment.
In this paper is exposed a quantitative and qualitative analysis, based on Risk Matrix Method, particularly...
Nanogels are extensively studied for diverse biomedical applications. One of the most relevant is the use as drugs nano-carriers for therapeutic purposes, increasing the bioactivity and transport of active components to specific sites or cells. Nanogels-based drug release formulations improve the effectiveness and safety of certain anticancer drugs and radiopharmaceuticals, minimizing its...
Purpose: The flattening filter free (FFF) mode (Elekta) was recently installed at our institution. We investigated FFF planning and delivery for stereotactic peripheral lung treatment as the increased dose rate of FFF mode can reduce the treatment time.
Methods: Ten lung cancer patients with peripheral lesions previously treated with VMAT SBRT were selected to span a range of target sizes and...
Machine learning algorithms that are both interpretable and accurate are essential in applications such as medicine where errors can have a dire consequence. Unfortunately, there is currently a tradeoff between accuracy and interpretability among state-of-the-art methods. Decision trees are interpretable and are therefore used extensively throughout medicine for stratifying patients. Current...
Despite the clear evidence that computed tomography provides very valuable information for diagnosis, there is a potential risk for the use of ionizing radiation. In CT, decreasing the dose of radiation increases the amount of noise in the images; therefore, the noise can hide anatomical details and decrease the detection of injuries. The Bilateral filter, proposed by Tomasi and Manduchi, is...
Metal artifacts are common in clinical images. Many methods for artifact reduction have been published to overcome this problem. In this work, three well-known methods and a new one were evaluated, compared and enhanced to achieve artifact suppression (linear interpolation (LI), normalized metal artifact reduction (NMAR) and Frequency split metal artifact reduction (FSMAR)). Furthermore, a new...
The Monte Carlo method (MC) has been commonly used in medical physics applications such as radiotherapy, radiation protection and nuclear medicine due to the stochastic nature of radiation and detection processes. In our country, during the last few years, new radiotherapy machines with novel technological advances have been acquired. Among this new equipment, the linear accelerator (linac)...
Sophisticated devices are used in Stereotactic Radiosurgery (SRS) for delivering small radiation beams in specific geometries. Computer planning systems are customized with specific dosimetric data corresponding to the specific machine.
At Instituto Nacional de Oncologia y Radiobiologia, an Apex micro multileafs collimator was adopted together with an Elekta Precise linear accelerator for SRS...
While pre-treatment VMAT QA is currently a clinical mainstay, there is growing interest in the use of QA methods that are more relevant to the actual patient treatment and are, in fact, capable of providing in vivo dosimetry. To this end, I will present a newly developed methodology for Monte Carlo based VMAT QA, which simultaneously provides the dose deposited in both the patient CT data set...
Introduction: Fiber-coupled plastic organic scintillator detectors are exceptional for the measurement of the absorbed dose to water in small MV photon beams. This is mostly because of their high degree of water equivalence which results in an almost negligible perturbation of the radiation field. However, these detectors are less ideal when the signal generation and detection is considered....
The first phase I/II clinical trial involving the application of particle beam radiation therapy (PBRT) with ions heavier than protons up were initiated at the University of California, San Francisco / Lawrence Berkeley National Laboratory (UCSF-LBNL) in 1975 [1–4]. This trial prospectively evaluated tumor responses to PBRT and collected information on the late effects. The last trial...
Fiber-coupled scintillators are known to exhibit a nonlinear response to high-LET beams, i.e. ionization quenching. Although corrections may be applied using e.g. Birks’ empirical formula such procedures are challenging and may even introduce errors.
Recent studies suggest that Cerenkov light produced in optical fiber cables may be used to circumvent the ionization quenching. The...
Purpose: This study is devoted to optimize and characterize the response of a multipoint plastic scintillator detector (mPSD) for in vivo dosimetry.
Methods: A 3 points mPSD was constructed and characterized in terms of response to interacting ionizing photons.The detector was composed of BCF-60, BCF-12 and BCF-10 scintillating fibers, separated from each other by segments of clear optical...
A NMR based experimental procedure to determine the dynamic viscosity ($\eta$) in Plasma solutionsis presented. An equation relating $\eta$ and the transversal proton magnetic relaxation time (T$_2$) is obtained after considering a fast exchange between the free and associated water inside the Plasma Solution, the dominant role of the associated water in proton magnetic relaxation, the...
Magnetic Resonance (MR) Imaging is a powerful noninvasive diagnostic technique based on the interaction of the nuclear spins in the biological medium with external magnetic fields. MR signal is affected by several physical properties or phenomena including nuclear relaxation times (T1, T2, T1rho), nuclear density, magnetic susceptibility, diffusion, perfusion, etc. However, MR images are...
Methods and results for commissioning and verification of the VMAT delivery chain at NPL are presented. The VMAT parameters for the combination of Pinnacle v9.8 with with Elekta’s Mosaiq® v1.6 record and verify system and Synergy and Versa HD linacs are discussed. Commissioning verification and gamma analysis results for three stablished IMRT QA deliveries are presented and compared, based on...
A detailed simulation of cross radiation in the PET and CT detectors of the tomographic bimodal system for small animals ClearPET/XPAD3-CT, was made using the Geant4 Monte Carlo code. A positron emitter radioactive point source (FDG-$^{18}$F) was located in the center of the tomographic system, inside a spherical water phantom. Positron-electron annihilations occurring within the phantom...
Real-time dosimetry for radiotherapy with high spatial resolution is a growing research field. Development of new radiotherapy techniques, such as intensity-modulated radiation therapy, stereotactic radiosurgery, and high dose rate brachyterapy among others, require high performance dosimetrics techniques. Even though different kinds of detection systems have been investigated to perform...
The motivation of this analysis was the knowledge of quantitative association between CT dosimetric quantities and operational factors and devise scanner-specific optimization strategies. The measure of indexes of kerma free in air and in standard phantoms (in a Siemens Sensation CT scanner), provided the main data for identification of statistical associations with operational factors and...
At INFN-LNL the SPES facility for the production of radioactive ion beams is constructing. This RIB new facility, besides being operated for nuclear physics studies, may play a pivotal role in the production of medically relevant radionuclides by means of the ISOL (Isotope Separation On-Line) technique.
The production of the radioactive isotopes will be obtained by nuclear reactions induced by...
In this review lecture, we will explore the physics behind the contemporary codes of practice for dosimetry based on standards of absorbed dose to water, such as the widely used protocols TRS 398 of the IAEA or TG 51 of the AAPM. In particular, we will review the basic concepts of cavity theory and take a pedagogic approach to understanding its role as an essential component of the formalism...
The traditional scheme for X-ray production is based on the well known X-ray tube, an evolution in technology started from the experiments performed by Crookes and finally by X-rays discovery by W. Röntgen in 1895. As known, X-ray tubes are mainly based on the impact of accelerated electron onto high atomic number anodes in order to produce photons by means of Bremsstrahlung and characteristic...
One of the main challenges of proton therapy today is to produce an equipment that, because of its size and cost, is accessible for general health centers. This way, this therapy will not only be possible in a few centers in developed countries. For this purpose, new equipment has been developed for a single treatment room and equipped with small size cyclotrons with modern technology...
The computational approach, also known as computational radiobiology, to study biological effects induced by ionizing radiations on living beings has being commonly used by many research groups in several applications like micro and nanodosimetry, radiotherapy, radiation protection, and space radiation. A group led by Bernal at University of Campinas, Sao Paulo, developed a biophysical model...
In vivo dosimetry is an essential tool for quality assurance programs, being a procedure commonly performed with thermoluminescent dosimeters (TLDs) or diodes. However, a type of dosimeter that has increasing popularity in recent years is metal-oxide-semiconductor field effect transistor (MOSFET) detector. MOSFET dosimeters fulfill all the necessary characteristics to realize a in vivo...
