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Coupled oscillators are among the simplest composite quantum systems in which the interplay of entanglement and interaction may be explored. We examine the effects of coupling on fluctuations of the coordinates and momenta of the oscillators in a single-excitation entangled state. We discover that coupling acts as a mechanism for noise transfer between one pair of coordinate and momentum and another. Through this noise transfer mechanism, the uncertainty product is lowered, on average, relatively to its non-coupled level for one pair of coordinate and momentum and it is enhanced for the other pair. This novel mechanism may be explored in precision measurements in entanglement-assisted sensing and metrology., Comment: 6 pages, 6 figures

An updated overview of recent results on Heavy-Ion induced reactions of interest for neutrinoless double beta decay is reported in the framework of the NUMEN project. The NUMEN idea is to study heavy-ion induced Double Charge Exchange (DCE) reactions with the aim to get information on the nuclear matrix elements for neutrinoless double beta (0νββ) decay. Moreover, to infer the neutrino average masses from the possible measurement of the half- life of 0νββ decay, the knowledge of the nuclear matrix elements is a crucial aspect. Uma visão geral atualizada dos resultados recentes sobre reações induzidas por íons pesados ​​de interesse para o decaimento beta duplo sem neutrinos é relatada na estrutura do projeto NUMEN. A ideia do NUMEN é estudar reações de Double Charge Exchange (DCE) induzidas por íons pesados ​​com o objetivo de obter informações sobre os elementos da matriz nuclear para o decaimento beta duplo sem neutrinos (0νββ). Além disso, para inferir as massas médias dos neutrinos a partir da possível medição da meia-vida do decaimento 0νββ, o conhecimento dos elementos da matriz nuclear é um aspecto crucial. 1308 012002

International audience; NUMEN aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involved in the half-life of the neutrinoless double beta decay (0νββ), by high-accuracy measurements of the cross sections of Heavy Ion (HI) induced Double Charge Exchange (DCE) reactions. First evidence about the possibility to get quantitative information about NME from experiments is found for the (^18O,^18Ne) and (^20Ne,^20O) reactions. Moreover, to infer the neutrino average masses from the possible measurement of the half-life of 0νββ decay, the knowledge of the NME is a crucial aspect. The key tools for this project are the high resolution Superconducting Cyclotron beams and the MAGNEX magnetic spectrometer at INFN Laboratori Nazionali del Sud in Catania (Italy). The measured cross sections are extremely low, limiting the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. A major upgrade of the LNS facility is foreseen in order to increase the experimental yield of at least two orders of magnitude, thus making feasible a systematic study of all the cases of interest.

International audience; The article describes the main achievements of the NUMEN project together with an updated and detailed overview of the related R&D activities and theoretical developments. NUMEN proposes an innovative technique to access the nuclear matrix elements entering the expression of the lifetime of the double beta decay by cross section measurements of heavy-ion induced Double Charge Exchange (DCE) reactions. Despite the fact that the two processes, namely neutrinoless double beta decay and DCE reactions, are triggered by the weak and strong interaction respectively, important analogies are suggested. The basic point is the coincidence of the initial and final state many-body wave functions in the two types of processes and the formal similarity of the transition operators. First experimental results obtained at the INFN-LNS laboratory for the$^{40}$Ca($^{18}$O,$^{18}$Ne)$^{40}$Ar reaction at 270MeV give an encouraging indication on the capability of the proposed technique to access relevant quantitative information. The main experimental tools for this project are the K800 Superconducting Cyclotron and MAGNEX spectrometer. The former is used for the acceleration of the required high resolution and low emittance heavy-ion beams and the latter is the large acceptance magnetic spectrometer for the detection of the ejectiles. The use of the high-order trajectory reconstruction technique, implemented in MAGNEX, allows to reach the experimental resolution and sensitivity required for the accurate measurement of the DCE cross sections at forward angles. However, the tiny values of such cross sections and the resolution requirements demand beam intensities much larger than those manageable with the present facility. The on-going upgrade of the INFN-LNS facilities in this perspective is part of the NUMEN project and will be discussed in the article.

The COTS power transistors based in GaN were exposed to TID effects by 10-keV X-rays. These HEMTs were tested in the On- and Off-state bias conditions. Switching tests were performed before and after irradiation steps. The devices were characterized at temperatures ranging from −50 °C to +75 °C. The results indicate that the GaN-technology is a great candidate to be used in harsh environments, because the tested devices have presented an expressive recovery of its parameters of Vth, gmmax and switching times, after accumulation of 350 krad of TID.

Assessing electronic systems regarding ionizing radiation is often costly and requires complex facilities capable of generating the ionizing radiation, and highly qualified human resources to fulfill all the requirements for the radiation tests. This work proposes a fast and low-cost setup to evaluate soft errors on digital programmable systems owing to Single Event Effects caused by ionizing radiation. Alpha particle sources allows to test these systems on a fast and simple procedure, with the advantage of evaluating also the system's sensitivity to ionizing radiation.

Electronic systems functionality degrades when these systems are operating in harsh environments such as those where they are exposed to ionizing radiation. Understanding and measuring these effects is extremely important in order to design systems that can operate reliably. This work discusses experimental data of heavy ion and x-ray radiation effects on a Commercial-Off-The-Shelf (COTS) low-cost microprocessor. The heavy ions test results suggest that, in this technology, the SRAM is more sensitive to SEE than flash memory. Ions with a LET higher than 5 MeV/mg/cm2 may disrupt the device's proper operation.

In this work we present an experimental setup mounted in one of the beam lines at the Sao Paulo 8UD Pelletron Accelerator in order to study Single Event Effects in electronic devices. The basic idea is to use elastic scattering collisions to achieve a low-flux with a high-uniformity ion beam to irradiate several devices. 12 C, 16 O, 28 Si, 35 Cl and 63 Cu beams were used to test the experimental setup. In this system it is possible to use efficiently LET values of 17 MeV/mg/cm 2 for an external beam arrangement and up to 32 MeV/mg/cm 2 for in-vacuum irradiation.

Electronic system functionality degrades when these systems are operating in harsh environments, such as those where they are exposed to ionizing radiation. Understanding and measuring these effects is extremely important in order to design systems that can tolerate ionizing radiation. This work discusses experimental data of Heavy Ion and X-Ray radiation effects on a Commercial-Off-The-Shelf low-cost microprocessor. The heavy ions irradiation results suggest that, in this technology, the SRAM is more sensible to SEE than Flash memory. Ions with a LET higher than 5 MeV/mg/cm2 may cause the device to stop working.

Electronic devices exposed to ionizing radiation exhibit degradation on their electrical characteristics, which may compromise the functionality of the device. Understanding the physical phenomena responsible for radiation damage, which may be specific to a particular technology, it is of extreme importance to develop methods for testing and recovering the devices. The aim of this work is to check the influence of thermal annealing processes and electric field applied during irradiation of Metal Oxide Semiconductor Field Effect Transistors (MOSFET) in total ionizing dose experiments analyzing the changes in the electrical parameters in these devices

In this work we have studied the radiation effects on MOSFET electronic devices. The integrated circuits were exposed to 10 keV X-ray radiation and 2.6 MeV energy proton beam. We have irradiated MOSFET devices with two different geometries: rectangular-gate transistor and circular-gate transistor. We have observed the cumulative dose provokes shifts on the threshold voltage and increases or decreases the transistor’s off-state and leakage current. The position of the trapped charges in modern CMOS technology devices depends on radiation type, dose rate, total dose, applied bias and is a function of device geometry. We concluded the circular-gate transistor is more tolerant to radiation than the rectangular-gate transistor.

As the use of Field Programmable Gate Arrays (FPGAs) in space and in other strategic areas increases, concerns about their tolerance to radiation also increases. This work reports the observation of soft and hard errors in a Xilinx Spartan-3E commercial off-the-shelf FPGA when exposed to low-dose rate, low energy X-rays during a dynamic test in which a LEON 3 soft-core processor was mapped in the FPGA.

In this work, the first successful SEE measurements with heavy ions in Brazil is reported. The heavy ions were produced at the Sao Paulo 8 UD Pelletron accelerator. 12C, 16O, 19F, 28Si, 35Cl, 63Cu and 107Ag heavy ion beams were used to test a commercial off-the-shelf transistor. During irradiation, the response of a pMOS transistor was continuously monitored to measure the SEE events. In order to achieve a uniform low intensity beam the heavy ions were Rutherford scattered at 15⁰ by a 275 μg/cm2 gold foil.

The interaction between a very thin macroscopic solenoid, and a single magnetic particle precessing in a external magnetic field B0, is described by taking into account the thermal and the zero-point fluctuations of stochastic electrodynamics. The inductor belongs to a RLC circuit without batteries and the random motion of the magnetic dipole generates in the solenoid a fluctuating current Idip(t), and a fluctuating voltage edip(t), with spectral distribution quite different from the Nyquist noise. We show that the mean square value 〈Idip2〉 presents an enormous variation when the frequency of precession approaches the frequency of the circuit, but it is still much smaller than the Nyquist current in the circuit. However, we also show that 〈Idip2〉 can reach measurable values if the inductor is interacting with a macroscopic sample of magnetic particles (atoms or nuclei) which are close enough to its coils.

The interaction of a microscopic magnetic dipole and the inductor of a RLC circuit without batteries, is described using the approach of stochastic electrodynamics. The purpose of this study is to clarify the effects of the current fluctuations on the paramagnetic behaviour of a sample of magnetic material which is close to a thin solenoid. A suppression is predicted in the average magnetization, even in the case in which the circuit temperature is arbitrarily close to the absolute zero.

We discuss a simple model where the electron is approximately described by a rapidly spinning disk of radius λ=ℏ/mc, such that the linear speed at its border is c. We assume that the particle's mass is uniformly distributed over the surface of the disk and its electric charge is strongly peaked around the border. It follows that the spin of the particle must be ℏ/2 and its magnetic moment should have a g factor equal to 2. We show that the electromagnetic self-energy of the particle is given by an expression which is similar to the result obtained in quantum electrodynamics.

Three facilities in Brazil are being prepared and upgraded to test and to qualify electronic devices regarding their tolerance to TID and SEE: a 60 kV X-ray source, a 1.7 MV Pelletron accelerator for low energy proton beams and an 8 MV Pelletron accelerator that produces heavy ion beams. MOSFET transistors were exposed to 10-keV X-rays and to 2.4 MeV protons extracted into air. During irradiation, characteristic curves were continuously measured to monitor the circuit's behavior relative to the accumulated dose. 12C, 16O, 28Si, 35Cl and 63Cu heavy ion beams were also used mostly to test the experimental setup, and verify beam uniformity at low fluence conditions, equilibrium charge state, and carbon stripper foil durability. To test the setup for SEE, a pMOS transistor was irradiated with 63 MeV 63Cu ions scattered at 15° by a 275 μg/cm2 gold foil. The setups are now available for TID and SEE studies in electronic devices.

In this work the distribution of potassium in sugarcane has been studied during its growth. The soil was prepared with natural fertilizers prepared with sugarcane bagasse. For the measurement of potassium concentration in each part of the plant, gamma-ray spectrometry was used to measure gamma-rays emitted from the radioisotope (40)K. The concentrations of potassium in roots, stems and leaves were measured every two to three months beginning about five months after planting the sugarcane. The results show a higher concentration of potassium at the beginning of plant development and over time, there is an oscillatory behavior in this concentration in each part of the plant, reaching a lower concentration in the adult plant. To describe the evolution of potassium distribution in sugarcane we proposed a phenomenological model assuming that the potassium incorporation rate is proportional to the difference between the element concentration in the plant and a very long term equilibrium value and it is coupled to a resource-limited growth model. The proposed model succeeded in interpreting the results for the potassium distribution in stems and leaves during the sugarcane growth.

IV-characteristics from ELT Overlapping Circular-Gate Transistors (O-CGT's) and rectangular-gate transistors are cross-checked after X-ray exposure. No degradation on O-CGT subthreshold behavior observed for doses up to 2.3 Grad. Devices were prototyped on standard 0.35 µm CMOS process.

We analyze wave propagation in the vacuum of Podolsky regularized electrodynamics. Two kinds of waves were found in the theory: the traditional non-dispersive waves of Maxwell electrodynamics, and a dispersive wave reminiscent of wave propagation in a collisionless plasma. Charged particle concentration was determined, and found to be huge in this vacuum. We interpret the results in terms of vacuum polarization effects induced in an otherwise classical theory., 7 pages, 1 figure, corrected typos, accepted for publication in Modern Physics Letters A

Recently, p-channel metal-oxide-semiconductor (pMOS) transistors were suggested as fit for the task of detecting and quantifying ionizing radiation dose. Linearity, small detection volume, fast readout, portability, low power consumption and low radiation attenuation are some of the pMOS advantages over PIN diode and thermoluminiscent dosimeters. A hand-held measurement system using a low power commercial off-the-shelf pMOSas the sensor would have a clear advantage due to the lower cost incurred by a standard technological process. In this research work, we tested the commercial device 3N163 regarding its behaviouras an X-ray sensor, as well as its possible application as a heavy-ion detector. To study the radiation effects of X-rays, a XRD-7000 (Shimadzu) X-ray diffraction setup was used to produce 10-keV effective energy photons. Heavy ions tests involved 12C, 16O, 19F, 28Si, 35Cl, 63Cu and 107Ag beams scattered at 15° by a 275 μg/cm2 gold target, which provide LETs (Linear Energy Transfer) from 4 to 40 MeV/mg/cm2. The signal readout was done using a 1 GHz oscilloscope with a 10-Gsamples/s conversion rate, high enough to permit the recording of transient pulses in the drain current. In this case, an ion can cause a current signal proportional to the ion beam used. Through this study it was found that a simple commercial pMOS device can be reliably used as a detector of X-rays as well as heavy ion detector.

We present a simple non-hermitian model to describe the phenomenon of asymmetric tunneling between two energy-degenerate sites coupled by a non-reciprocal interaction without dissipation. The system was described using a biorthogonal family of energy eigenvectors, the dynamics of the system was determined by the Schr\"odinger equation, and unitarity was effectively restored by proper normalization of the state vectors. The results show that the tunneling rates are indeed asymmetrical in this model, leading to an equilibrium that displays unequal occupation of the degenerate systems even in the absence of external interactions., Comment: 14 pages, 5 figures, submitted to Mod. Phys. Lett. B

We show how the modified electromagnetic vacuum of a resonant optical cavity can be used to manipulate the collisional dynamics between cold atoms by a modification of spontaneous emission times. Multiparticle entanglement and a higher spectral density of modes enhance spontaneous emission and alter the dynamics of cold collisions. A specific situation is considered and we show this effect can be observed as a large suppression in trap-loss rates.

We show how the indistinguishable nature of the interaction of a collection of cold atoms with the electromagnetic field in an optical cavity leads to entanglement and a very fast radiative decay dynamics. This acceleration of spontaneous emission has important consequences in the process known as radiative escape, one of the most important sources of trap loss due to cold collisions. In this process, a pair of atoms excited at some internuclear separation R C picks up kinetic energy on the long range excited state potential. The spontaneous emission time is a crucial parameter in this dynamics for it will determine whether or not the pair gains enough kinetic energy to escape from the trap. Considering realistic experimental parameters we can predict a very large suppression of radiative escape trap loss in a sample of cold rubidium atoms.

We show how the dynamics of collisions between cold atoms can be manipulated by a modification of spontaneous emission times. This is achieved by placing the atomic sample in a resonant optical cavity. Spontaneous emission is enhanced by a combination of multiparticle entanglement together with a higher density of modes of the modified vacuum field, in a situation akin to superradiance. A specific situation is considered and we show that this effect can be experimentally observed as a large suppression in trap-loss rates., Comment: RevTex, 2 EPS figures; scheduled for Phys. Rev. Lett. 19 Feb 01, with minor changes

We discuss, in the context of classical electrodynamics with a Lorentz invariant cut-off at short distances, the self-force acting on a point charged particle. It follows that the electromagnetic mass of the point charge occurs in the equation of motion in a form consistent with special relativity. We find that the exact equation of motion does not exhibit runaway solutions or non-causal behavior, when the cut-off is larger than half of the classical radius of the electron., Comment: 17 pages, 1 figure

We present a simple method to analyze time series, and estimate the parameters needed to control chaos in dynamical systems. Application of the method to a system described by the logistic map is also shown. Analyzing only two 100-point time series, we achieved results within 2% of the analytical ones. With these estimates, we show that OGY control method successfully stabilized a period-1 unstable periodic orbit embedded in the chaotic attractor.

Neutrinoless double beta decay of nuclei, if observed, would have important implications on fundamental physics. In particular it would give access to the effective neutrino mass. In order to extract such information from 0νββ decay half-life measurements, the knowledge of the Nuclear Matrix Elements (NME) is of utmost importance. In this context the NUMEN and the NURE projects aim to extract information on the NME by measuring cross sections of Double Charge Exchange reactions in selected systems which are expected to spontaneously decay via 0νββ. In this work an overview of the experimental challenges that NUMEN is facing in order to perform the experiments with accelerated beams and the research and development activity for the planned upgrade of the INFN-LNS facilities is reported.

The NUMEN project aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involved in the half-life of the neutrinoless double beta decay (0νββ). In this view measurements of Heavy Ion (HI) induced Double Charge Exchange (DCE) reaction cross sections are performed with high-accuracy. In particular, the (18O,18Ne) and (20Ne,20O) reactions are used as tools for β+β+ and β-β- decays, respectively. In the experiments, performed at INFN - Laboratory Nazionali del Sud (LNS) in Catania, the beams are accelerated by the Superconducting Cyclotron (CS) and the reaction ejectiles are detected the MAGNEX magnetic spectrometer. The measured cross sections are challengingly low (a few nb), being the total reaction cross section much larger (a few b), thus a high sensitivity and a large rejection capability are demanded to the experimental set-up. This limits the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. A major upgrade of the LNS facility is under way in order to increase the experimental dataset of more than two orders of magnitude, still preserving the high sensitivity of the present set-up. When accomplished this effort will make the INFN-LNS as the state-of-the-art research infrastructure for the systematic study of all the cases of interest for 0νββ. In this view, frontiers technologies are going to be adopted for the accelerator and the detection systems. In parallel, advanced theoretical models are being developed in order to extract the nuclear structure information from the measured cross sections.