Applications In Nuclear Physics Research Articles

Observation on the absorption of linearly polarized light by 133Cs atoms with optically resolved hyperfine structure

The absorption of linearly polarized light by 133Cs atoms is desired to be well known in many applications of atomic physics. For implementing this requirement, a simplified analytical form for the absorption of linearly polarized light by 133Cs atoms with optically resolved hyperfine structure is derived. Based on the obtained analytical form, optical absorption cross-sections of 133Cs atoms are simulated. An experiment is designed to further study the absorption of linearly polarized light by 133Cs atoms. Theory and experiment show that the influence of linearly polarized light on the distribution of 133Cs atoms will in turn affect the optical absorption. In order to demonstrate this kind of influence, an example for the measurement of the 133Cs vapor density is shown theoretically and experimentally, and a method of polynomial fit is proposed to reduce this influence.

Gorkov algebraic diagrammatic construction formalism at third order

Background: The Gorkov approach to self-consistent Green's function theory has been formulated by Som\`a, Duguet, and Barbieri in [Phys. Rev. C 84, 064317 (2011)]. Over the past decade, it has become a method of reference for first-principles computations of semimagic nuclear isotopes. The currently available implementation is limited to a second-order self-energy and neglects particle-number nonconserving terms arising from contracting three-particle forces with anomalous propagators. For nuclear physics applications, this is sufficient to address first-order energy differences (i.e., two neutron separation energies, excitation energies of states dominating the one-nucleon spectral function), ground-state radii and moments on an accurate enough basis. However, addressing absolute binding energies, fine spectroscopic details of $N\ifmmode\pm\else\textpm\fi{}1$ particle systems or delicate quantities such as second-order energy differences associated with pairing gaps, requires going to higher truncation orders.Purpose: The formalism is extended to third order in the algebraic diagrammatic construction (ADC) expansion with two-body Hamiltonians.Methods: The expansion of Gorkov propagators in Feynman diagrams is combined with the algebraic diagrammatic construction up to the third order as an organization scheme to generate the Gorkov self-energy.Results: Algebraic expressions for the static and dynamic contributions to the self-energy, along with equations for the matrix elements of the Gorkov eigenvalue problem, are derived. It is first done for a general basis before specifying the set of equations to the case of spherical systems displaying rotational symmetry. Workable approximations to the full self-consistency problem are also elaborated on. The formalism at third order it thus complete for a general two-body Hamiltonian.Conclusions: Working equations for the full Gorkov-ADC(3) are now available for numerical implementation.

Micromechanical mode-localized electric current sensor

This paper outlines the design of a novel mode-localized electric current sensor based on a mechanically sensitive element of weakly coupled resonator systems. With the advantage of a high voltage sensitivity of weakly coupled resonator systems, the current under test is converted to voltage via a silicon shunt resistor, which causes stiffness perturbation to one resonator. The mode-localization phenomenon alters the energy distribution in the weakly coupled resonator system. A theoretical model of current sensing is established, and the performance of the current sensor is determined: the sensitivity of the electric current sensor is 567/A, the noise floor is 69.3 nA/√Hz, the resolution is 183.6 nA, and the bias instability is 81.6 nA. The mode-localized electric current sensor provides a new approach for measuring sub-microampere currents for applications in nuclear physics, including for photocurrent signals and transistor leakage currents. It could also become a key component of a portable mode-localized multimeter when combined with a mode-localized voltmeter. In addition, it has the potential for use in studying sensor arrays to achieve higher resolution.

Generation of metastable krypton using a 124-nm laser

We have realized the optical excitation of krypton to a metastable level with an efficiency as high as $23\phantom{\rule{0.16em}{0ex}}%$ using near-resonant 124-nm light produced by four-wave mixing in mercury vapor. Self-absorption in mercury is circumvented by adjusting the detuning and phase matching according to experimental and theoretical characterizations. Density-matrix calculations of the metastable krypton generation agree with the measured dependencies of the excitation efficiency, indicating pathways towards a further improvement. The obtained excitation efficiency, being one order of magnitude higher than that of previously demonstrated techniques, enables an extension of the metastable density regime for atomic physics applications, including magnetometry, atom lithography, and radioisotope dating.

The time-reversal odd side of a jet

We re-examine the jet probes of the nucleon spin and flavor structures. We find for the first time that the time-reversal odd (T-odd) component of a jet, conventionally thought to vanish, can survive due to the non-perturbative fragmentation and hadronization effects. This additional contribution of a jet will lead to novel jet phenomena relevant for unlocking the access to several spin structures of the nucleon, which were thought to be impossible by using jets. As examples, we show how the T-odd constituent can couple to the proton transversity at the Electron Ion Collider (EIC) and can give rise to the anisotropy in the jet production in e+e− annihilations. We expect the T-odd contribution of the jet to have broad applications in high energy nuclear physics.

Stabilization and control of persistent current magnets using variable inductance

Ultra-stable, tunable magnetic fields are desirable for a wide range of applications in medical imaging, electron microscopy, quantum science, and atomic physics. Superconducting magnets operated in persistent current mode, with device current flowing in a closed superconducting loop disconnected from a power source, are a common approach for applications with the most stringent requirements on temporal field stability. We present a method for active control of this persistent current by means of dynamic inductance change within the superconducting circuit. For a first realization of this general technique, we consider a variable superconducting inductor placed in series with the main magnet. The inductor acts as a dynamic flux storage device capable of transferring flux to or from the main magnet through inductance change. This allows for fine and fast adjustments of the persistent current without the use of thermal switches that limit the speed and accuracy of many present-day methods. With first experiments employing this technique, we demonstrate stabilization of a 1.95 T Nb–Ti round lens for electron microscopy against decay resulting from residual losses in the superconducting circuit, and more generally show flexibility for precise control over the magnitude and waveform of the persistent current.

A new method to improve the generalization ability of neural networks: A case study of nuclear mass training

As one of the fundamental input quantities in nuclear physics, an accurate calculation of the nucleus mass is necessary. Currently, neural network methods improve the accuracy of mass models. However, the reliability for extrapolation cannot be predicted. In this paper, a training method of neural network method is proposed. A fitting method similar to the macroscopic microscopic mass model is used. After fitting the liquid drop model the neural network method is used for training, and then afterwards the parameters are refitted and the neural network model is retrained, and so on several times. Taking the Weizsäcker-Skyrme (WS) model as an example, for known nuclei, it can improve the calculation results by about 20% over the original results. The extrapolation results for unknown neutron-deficient nuclei are also significantly improved. We believe that this method can calculate the masses of partially unknown nuclei more accurately. Further, it may be possible to improve the extrapolation capability of the neural network method using this approach. It is hoped that the present work can be useful for nuclear physics experiments and applications of neural network methods.

Monte Carlo simulations of $$\gamma $$-directional correlations and their application on FIFRELIN cascades

Angular distribution and correlation measurements are an essential part in nuclear structure experiments, especially when spectroscopic information of a specific nucleus is unknown. In most cases, the experimental determination of the spins, parities of the studied nuclear states, as well as the possible mixing between two electric/magnetic multipoles of a transition are determined using angular correlation measurements. In this work, the full effect of directional {\gamma}-correlations is simulated, by using the formal theory of angular distributions. The density matrix formalism along with its multipole expansions called statistical tensors is employed, enabling to perform a full simulation of the angular correlation effects in a cascade of an arbitrary number of {\gamma} transitions. A triple {\gamma} angular correlation simulation is demonstrated for the first time. The present approach was coupled with the Monte Carlo code FIFRELIN, which can simulate the de-excitation of fission fragments or of excited nuclei after neutron capture. It provides a complete description of the spatial distributions of all the {\gamma} rays in the cascade, that can be used for simulation purposes in various applications both in nuclear and particle physics. The potential for a novel approach in data analysis of angular correlation measurements is discussed thoroughly.

Generation and characterization of isolated attosecond pulses at 100 kHz repetition rate

The generation of coherent light pulses in the extreme ultraviolet (XUV) spectral region with attosecond pulse durations constitutes the foundation of the field of attosecond science. Twenty years after the first demonstration of isolated attosecond pulses, they continue to be a unique tool enabling the observation and control of electron dynamics in atoms, molecules, and solids. It has long been identified that an increase in the repetition rate of attosecond light sources is necessary for many applications in atomic and molecular physics, surface science, and imaging. Although high harmonic generation (HHG) at repetition rates exceeding 100 kHz, showing a continuum in the cutoff region of the XUV spectrum, was already demonstrated in 2013, the number of photons per pulse was insufficient to perform pulse characterization via attosecond streaking, let alone to perform a pump-probe experiment. Here we report on the generation and full characterization of XUV attosecond pulses via HHG driven by near-single-cycle pulses at a repetition rate of 100 kHz. The high number of 10 6 XUV photons per pulse on target enables attosecond electron streaking experiments through which the XUV pulses are determined to consist of a dominant single attosecond pulse. These results open the door for attosecond pump-probe spectroscopy studies at a repetition rate 1 or 2 orders of magnitude above current implementations.

Light outputs of yttrium doped BaF_2 crystals irradiated with neutrons

The fast luminescence component of barium fluoride (BaF_2) crystals with a subnanosecond decay time can find wide application in particle physics and nuclear physics. However, the slow luminescence component with the 630 ns decay time could cause pile-up signals at a high rate environment. Doping of BaF2 crystals with rare earth elements suppresses the slow emission component, but at the same time the radiation hardness of the crystals deteriorates. This work presents the results of studying crystal samples, both pure BaF2 and those doped with yttrium in a proportion of 1 at.%Y, 3 at.%Y and 5 at.%Y, irradiated with a fast neutron fluence of about 2.3×1014 n/cm2. Their light output and decay kinetics were measured before and after irradiation. It is found that the light output loss of a pure BaF2 crystal after irradiation is about 7%, and the light output loss of yttrium doped samples after irradiation is about two times higher. The measurement results demonstrate that after irradiation the fast component of each sample has a relative light output loss 2–3% larger than the slow one.

Tracking and Monitoring of the Alignment System Used for Nuclear Physics Experiments

The ELI-NP (Extreme Light Intensity—Nuclear Physics) project, developed at the Horia Hulubei National Institute for RD in Physics and Nuclear Engineering (IFIN-HH), has included one component dedicated to the study of interactions between brilliant gamma-ray and matter, with applications in nuclear physics and the science of materials. The paper is focused on the interaction chamber, an important part of the facility which hosts the experiment’s samples. The interaction chamber is endowed with a mobile sample support (holder), which automatically tracks the γ-ray beam. The γ-ray radiation source presents a slight variation of the direction of the emitted radiation in time. The built system ensures the permanent collimation between the γ-ray beam and the sample that is being investigated. This is done with two electric motors, which have a symmetrical movement with respect to the center of a rectangle. The specific measures taken by the design and implementation that permit to reach performances of tracking system are emphasized in the paper. The methodology considers the relative displacement between the detectors with which the laboratory is equipped and the absolute position in space of the sample boundary. The control of this motion is designed to respect the symmetry of the system. Both facets of the project (hardware and software) are detailed, emphasizing the way in which the designers ensured compliance with the system of real-time operation conditions of the tracking and monitoring system.

DEVELOPMENT OF LOCAL GREEN SPINACH PLANTS BY APPLICATION OF NUCLEAR PHYSICS METHODS (STANDARD MULTI-GAMMA IRRADIATION)

This research aims to develop local green spinach with the application of nuclear physics to obtain a superior cultivar that adapts to dryland conditions, is tolerant of pests and diseases, and has high production. This research use irradiation, observation, sampling, careful selection, purification, comparative, and interpretation as the methods. Research procedures: 1) preparing samples, 2) land preparation, 3) sample irradiation at a dose of 2000 rads for 30 minutes, 4) equality of samples that have been irradiated, 5) when the plants were one week old, the spinach seedlings were transferred to a different area has been prepared with a spacing of 50 cm × 30 cm for pickled spinach, 6) weeding and fertilizing spinach plants as needed, 7) careful selection (individual selection), 8) harvesting after planting spinach is approximately 2-3 weeks old for commercial purposes, 9) maintaining several tree crops spinach that will use as seeds for further development, 10) harvesting, cleaning, and store in foil bags to avoid pests, 11) determining the nutritional content of spinach leaves with an analytical service model. The results showed that the development of local green spinach plants by application of nuclear physics methods (multi-gamma irradiation) produces a superior cultivar of local green spinach that is adaptive to dryland conditions, tolerant of pests and diseases, and production significantly increases. The range and average output of superior cultivar of local green spinach irradiated by multi-gamma were 4.86-5.46 t/ha and 5.25 t/ha, with a percentage increase in production of 38.29 %.

Frequency-quintupled laser at 308 nm for atomic physics applications.

We report on the development of a compact continuous-wave frequency-quintupled laser at 308 nm, which is based on a fiber laser operating in the telecom band. Three consecutive frequency conversion stages in nonlinear crystals are employed to achieve a 2ν+3ν=5ν frequency mixing. The performance of the laser system is demonstrated by linear absorption spectroscopy of a narrow intercombination line in zinc.

Stable 2 W continuous-wave 261.5 nm laser for cooling and trapping aluminum monochloride.

We present a high-power tunable deep-ultraviolet (DUV) laser that uses two consecutive cavity enhanced doubling stages with LBO and CLBO crystals to produce the fourth harmonic of an amplified homebuilt external cavity diode laser. The system generates up to 2.75 W of 261.5 nm laser light with a ∼2 W stable steady-state output power and performs second harmonic generation in a largely unexplored high intensity regime in CLBO for continuous wave DUV light. We use this laser to perform fluorescence spectroscopy on the A1Π ← X1Σ+ transition in a cold, slow beam of AlCl molecules and probe the A1Π|v' = 0, J' = 1〉 state hyperfine structure for future laser cooling and trapping experiments. This work demonstrates that the production of tunable, watt-level DUV lasers is becoming routine for a variety of wavelength-specific applications in atomic, molecular and optical physics.

(Industrial Electrochemistry and Electrochemical Engineering Division New Electrochemical Technology (NET) Award) Pulse Reverse HF-Free Electropolishing of Niobium Superconducting Radio Frequency (SRF) Cavities for Nuclear Physics and High Energy Physics Applications

On behalf of Faraday Technology, Inc., we are honored to receive the 2021 New Electrochemical Technology (NET) award of the Industrial Electrochemistry & Electrochemical Engineering (IE&EE) division for pulse reverse FARADAYIC® HF-FREE Electropolishing of niobium SRF cavities. The NET award was endowed by the Dow Chemical Company Foundation to recognize significant advances in industrial electrochemistry. We addressed the subject innovation as a multidisciplinary team of electrochemists, engineers and technologists.Niobium superconducting radio frequency (SRF) cavities are used in particle accelerators such as the Large Hadron Collider (LHC) to support nuclear/high energy physics applications. To achieve their required performance, the niobium SRF cavities are electropolished using nine-parts sulfuric acid to one-part hydrofluoric acid.[1] The conventional process follows the well-established “viscous salt-film” model for electropolishing.[2] The conventional electrolyte imparts an extreme hazard to workers requiring costly safety protocols with extensive worker protection (see Fig. 1a).[3] ,[4] To commercialize niobium SRF cavity electropolishing, a simpler, cost-effective industrially compatible process was required.We developed a pulse reverse process to electropolish niobium coupons in low concentration (<5 wt%) aqueous sulfuric acid electrolytes devoid of hydrofluoric acid.[5] The surface roughness was the same as that observed using conventional DC electropolishing.[6] We transitioned the work from coupons to single-cell niobium cavities SRF and the performance was the highest observed at the DOE’s Fermi National Accelerator Facility.[7] ,[8] Due to the avoidance of the safety protocols associated with the conventional process (see Fig. 1b), the capital and operating costs of the pulse reverse electropolishing process were considerably less than the conventional process.[9] Finally, the pulse reverse process was patented and transitioned to DOE’s Thomas Jefferson National Accelerator Facility.[10] ,[11] Finally, the pulse reverse process was adapted to other strongly passive materials.While reviewing the technology developments leading to and associated with the niobium pulse reverse electropolishing process, we will illustrate lessons learned during the development of industrial innovations.[12] [1] H. Tian, S. Corcoran, C. Reece, and M. Kelly, J. Electrochem. Soc., 155, D563 (2008). [2] P. A. Jacquet, Trans. Electrochem. Soc., 69, 629 (1936). [3] T. Dote and K. Kono, Jap. J. Occupational Medicine and Traumatology, 52, 3, 189 (2004). [4] J. Mammoser, “Chemical Safety Awareness for SRF Cavity Work” U.S. Particle Accelerator School, January 19, 2015 (accessed June 9, 2020) https://www.jlab.org/indico/event/98/ other-view?fr=no&detailLevel=contribution&view=standard& showSession=all&showDate=all [5] M. Inman, E. J. Taylor, and T. D. Hall, J. Electrochem. Soc., 160, E94 (2013). [6] M. Inman, T. Hall, E. J. Taylor, C. Reece, and O. Trofimova, Paper TOPO012, Proc. SRF2011, Chicago, IL (2011). [7] E. J. Taylor, T. Hall, M. Inman, S. Snyder, and A. Rowe, Electropolishing of Niobium SRF Cavities in Low Viscosity Aqueous Electrolytes without Hydroflouric Acid, Paper TUP054, Proc. SRF2013, Paris, France, Sept 2013. (ISBN 978- 3-95450-143-4) [8] A. Rowe, A. Grassellino, T. Hall, M. Inman, S. Snyder, and E. Taylor, Paper No. TUIOC02, Proc. SRF2013, Paris, France, Sept 2013. (ISBN 978-3-95450-143-4) [9] E. J. Taylor, M. Inman, T. Hall, S. Snyder, A. Rowe, and D. Holmes, Paper MOPB092, Proc. SRF2015, Whistler, BC, Canada (2015). [10] E. J. Taylor, M. E. Inman, and T. D. Hall, U.S. Pat. No. 9,006,147 issued April 14, 2015. [11] E. J. Taylor, M. E. Inman, and T. D. Hall, U.S. Pat. No. 9,987,699 issued June 5, 2018. [12] E.J. Taylor, M.E. Inman, H.M. Garich, H.A. McCrabb, S.T. Snyder, T.D. Hall in Electrochemical Engineering: The Path from Discovery to Product Alkire, Bartlett, Koper (eds) Wiley-VCH (2019). Figure 1

Outlook for nuclear physics research in Belarus

The future nuclear physics research capabilities for scientists from Belarus are discussed. The following branches for the activity: megascience class research platforms created in Russia and the European Union, a new generation of ionizing radiation sources, use of the world nuclear science network for short-term research and, monitoring of nuclear power plants are debated. The purposes of nuclear physics research are suggested to be a balanced combining of the further penetration deep into the matter, to clarify its status and time evolution and, the routine activity associated with clarifying the details of the world, for which sufficiently well-developed models have already been created. Further, the goals of nuclear physics research are specified. They include preventing the loss of knowledge in the field of nuclear physics; conservation of the acceptable qualification and its reproducibility, maintaining the appropriate level of the engineering corps for the perception of the latest knowledge. This article is based on the author’s personal experience in participating in projects of high scientific significance. The route of considering the areas of application of nuclear physics scientists’ efforts is formed according to the principle of maximum return from the highly qualified personnel (PhDs and doctors of science). Ain importance of training undergraduates and graduate students for a scientific career is underlined. Finally, a need to maintain a high level of knowledge in the branch for the expertise upon the request of the government to secure and develop the country is pointed out.

Effect of the deformation parameter on the nonrelativistic energy spectra of the q-deformed Hulthen-quadratic exponential-type potential

In this study, an approximate solution of the Schr�dinger equation for the q-deformed Hulthen-quadratic exponential-type potential model within the framework of the Nikiforov�Uvarov method was obtained. The bound state energy equation and the corresponding eigenfunction was obtained. The energy spectrum is applied to study H2, HCl, CO and LiH diatomic molecules. The effect of the deformation parameters and other potential parameters on the energy spectra of the system were graphically and numerically analyzed in detail. Special cases were considered when the potential parameters were altered, resulting in deformed Hulthen potential, Hulthen potential, deformed quadratic exponential-type potential and quadratic exponential-type potential. The energy eigenvalues expressions agreed with what obtained in literature. Finally, the results can find many applications in quantum chemistry, atomic and molecular physics.

Applications of Mathematics and Nuclear Physics in Medicine

Abstract: This research paper examines the applications of mathematics and physics in medicine. Mathematical equations governing the physics behind nuclear medicine are deconstructed; the equations include the radioactive decay equation, nuclide uptake formula, formula for the total electric field, quaternions and their role in the geometry of CT and x-ray scans, the use of complex numbers and quaternions in CAT scans, and the utilization of partial differential equations in image processing. On the other hand, physics supports medicines in different areas, including medical imaging through popular MRI and ultrasound techniques. It contributes to therapy through radiation, ultrasonic technologies, laser physics, and vibrational medicine. Nuclear medicine relies on radioactive tracers, while non-ionizing radiation technologies support laser surgery; ultrasound imaging, and UV light treatments are used for diagnosing and treating chronic illnesses. Radiation oncology medical physicists apply medical physics for the assessment and monitoring of the safety of staff and patients involved in radiation therapy, with electromagnetism offering support in neural engineering, signal analysis, quantum electronics, and in studying the nervous system

Two-dipole and three-dipole interaction coefficients of group XII elements

Study of long-range interactions is increasingly becoming essential due to its various applications in cold atomic physics. These interactions can be conveniently expressed in terms of various dispersion coefficients. In the present work, theoretical calculations have been carried out for the two-dipole (C6), and three-dipole (C9) dispersion coefficients among the group XII atoms and their ions, viz. Zn, Cd, Hg, Zn+, Cd+, and Hg+. To obtain these coefficients, the dynamic dipole polarizabilities and reduced matrix elements required are evaluated using the relativistic methods. Further, using the calculated matrix elements, the oscillator strengths corresponding to leading transitions and static dipole polarizabilities of these atoms and ions are determined for the comparison purposes.

Quantum simulation of open quantum systems in heavy-ion collisions

We present a framework to simulate the dynamics of hard probes such as heavy quarks or jets in a hot, strongly coupled quark-gluon plasma (QGP) on a quantum computer. Hard probes in the QGP can be treated as open quantum systems governed in the Markovian limit by the Lindblad equation. However, due to large computational costs, most current phenomenological calculations of hard probes evolving in the QGP use semiclassical approximations of the quantum evolution. Quantum computation can mitigate these costs and offers the potential for a fully quantum treatment with exponential speed-up over classical techniques. We report a simplified demonstration of our framework on IBM Q quantum devices and apply the random identity insertion method to account for cnot depolarization noise, in addition to measurement error mitigation. Our work demonstrates the feasibility of simulating open quantum systems on current and near-term quantum devices, which is of broad relevance to applications in nuclear physics, quantum information, and other fields.