Magnetic Detector Research Articles

General Failure Modes and Effects Analysis for Accelerator and Detector Magnet Design at JLab

The aim of this article is to develop a risk management procedure, which could be applied to the magnet design process, for both superconducting and normal magnets at the Jefferson Laboratory (JLab). This procedure allowed us to identify the key risks at each of the critical phases of design and propose procedures, tests, and checks to mitigate each risk. In this article, we present a qualitative and quantitative risk management procedure commonly referred to a “failure modes and effects analysis.” As part of this procedure, we calculated a risk priority number (RPN) for each activity of the process, identified the most critical activities and proposed mitigation activities, which in turn resulted in a revised RPN. Another benefit of this procedure was the identification of appropriate “control and hold” points within the design process, which allowed one to review and approve a particular outcome before proceeding to the next sequential activity.

Novel Benchtop Magnetic Particle Spectrometer for Process Monitoring of Magnetic Nanoparticle Synthesis.

Magnetic nanoparticles combine unique magnetic properties that can be used in a variety of biomedical applications for therapy and diagnostics. These applications place high demands on the magnetic properties of nanoparticles. Thus, research, development, and quality assurance of magnetic nanoparticles requires powerful analytical methods that are capable of detecting relevant structural and, above all, magnetic parameters. By directly coupling nanoparticle synthesis with magnetic detectors, relevant nanoparticle properties can be obtained and evaluated, and adjustments can be made to the manufacturing process in real time. This work presents a sensitive and fast magnetic detector for online characterization of magnetic nanoparticles during their continuous micromixer synthesis. The detector is based on the measurement of the nonlinear dynamic magnetic response of magnetic nanoparticles exposed to an oscillating excitation at a frequency of 25 kHz, a technique also known as magnetic particle spectroscopy. Our results underline the excellent suitability of the developed magnetic online detection for coupling with magnetic nanoparticle synthesis based on the micromixer approach. The proven practicability and reliability of the detector for process monitoring forms the basis for further application fields, e.g., as a monitoring tool for chromatographic separation processes.

On the measurements of magnetic nanoparticle concentration in a biological medium using a superconducting quantum magnetometer

Magnetic nano-particles are used in medicine both as medical means, and for the transport of medicines in the pathological area of an organism. Simultaneous influence on these particles of ultrasonic radiation and a constant magnetic field allows summarising a magnetic field of an nano-particles ensemble to the value, sufficient for its registration by the remote magnetic detector. The parity connecting the measured magnetic flux of the nanoparticles with parameters of the particles, ultrasound, and the measuring system using as the magnetic detector superconducting quantum magnetometer is received. Calculations have shown, that such a system can measure a concentration of the nano-particles in colloidal solution, modeling the biological medium, in the unattainable earlier dynamic range of values (from 1 vol % to 10−7 vol %).

Nondestructive Evaluation of Track and Haulage Ropes of Aerial Ropeway Installation in India—A Case Study

The wire ropes in steel material are generally used in harbours, on ships, haulage applications in mine winders, aerial ropeway carrying, haulage/track ropes for transportation of passengers and in many industrial fields. The properties of high axial strength and flexibility in bending, convert wire ropes into imperative load transmission components for many industrial applications. The exhaustive usage of these ropes deteriorates with its use over the course of period. The conduct of wire rope inspection has make one’s way expeditiously over the past few decades. To perform nondestructive tests of rope is a way how to analyse the real condition of ropes during their running operation. It became very necessary to evaluate ropes during their live condition in the interest to facilitate substitution of the rope in stipulated period and also for strengthening risk-free duration of working when discard requirements failed to attained. Available magnetic rope flaw detectors are now became much easier to set off and yield a paramount component of steel wire ropes verification or evaluation. The results of tests from these equipment’s capable of providing certain appraises of safety concern regarding steel wire rope parameters such as loss of metallic cross-sectional area and localised faults. It also provides further accurate baseline in establishing the state and rest duty period of a wire rope. A conducted research result depicts the level and the wide range of flaws, distribution pattern of localized defects such as concentrated or dispersive broken wires. This technical paper on nondestructive evaluation work being sponsored by Indian industry, illustrates the method of nondestructive testing applied and analysis of condition of haulage and track ropes including safety recommendations for further continuance in service.

Measurement of Low-energy Cosmic-Ray Electron and Positron Spectra at 1 au with the AESOP-Lite Spectrometer

Abstract We report on a new measurement of the cosmic ray (CR) electron and positron spectra in the energy range of 20 MeV–1 GeV. The data were taken during the first flight of the balloon-borne spectrometer Anti Electron Sub Orbital Payload (AESOP-Lite), which was flown from Esrange, Sweden, to Ellesmere Island, Canada, in 2018 May. The instrument accumulated over 130 hr of exposure at an average altitude of 3 g cm−2 of residual atmosphere. The experiment uses a gas Cerenkov detector and a magnetic spectrometer, consisting of a permanent dipole magnet and silicon strip detectors (SSDs), to identify particle type and measure the rigidity. Electrons and positrons were detected against a background of protons and atmospheric secondary particles. The primary CR spectra of electrons and positrons, as well as the re-entrant albedo fluxes, were extracted between 20 MeV and 1 GeV during a positive solar magnetic polarity epoch. The positron fraction below 100 MeV appears flat, suggesting diffusion-dominated solar modulation at low rigidity. The all-electron spectrum is presented and compared with models from a heliospheric numerical transport code.

Novel platform for the multidimensional analysis of magnetic nanoparticles

The success of Magnetic Particle Imaging (MPI) as a clinical imaging modality is inextricably linked to the availability of purpose-build magnetic nanoparticles (MNP). Attempts to develop MNP with tailored properties and predictable MPI-performance are underway and still of great debate. However, it is well-known that the MPI performance is hampered by the size distribution present in MNP systems. The hyphenation of asymmetric flow field-flow fractionation (AF4) with on-line detectors has proven to provide reliable multidimensional information of MNP size distributions in a quasi-closed system without additional preparation steps. We recently introduced a novel combination of AF4 with a magnetic detector. This detector is based on the same physical principle as MPI, called Magnetic Particle Spectroscopy (MPS), which has already proven a straightforward technique for MNP specific quantification and characterization. In this study we demonstrate that the AF4 multidetector approach, including our MPS detector, is feasible to assist the targeted development of MNP with optimized imaging capabilities in MPI by directly measuring the MNP size as well as the indispensable magnetic functionality. Furthermore, the new platform provides important insights into the physics of MNP and can be used for quality control of MNP in biomedical applications.

Design and parametric analysis of a wide-angle polarization-insensitive metamaterial absorber with a star shape resonator for optical wavelength applications

Optical wavelengths considered as the key source of electromagnetic waves from the sun, and metamaterial absorber (MMA) enables various applications for this region like real invisible cloaks, color imaging, magnetic resonance imaging, light trapping, plasmonic sensor, light detector, and thermal imaging applications. Contemplated those applications, a new wide-angle, polarization-insensitive MMA is presented in this study. The absorber was formatted with three layers that consisted of a sandwiched metal-dielectric-metal structure. This formation of metamaterial absorber showed a good impedance match with plasmonic resonance characteristics. The structure was simulated using the FIT and validated with the FEM. A variety of parametric studies were performed with the design to gain best physical dimension. The mechanism of absorption also explained immensely by various significant analysis. The design had average 96.77% absorption from wavelengths of 389.34 nm to 697.19 nm and a near-perfect absorption of 99.99% at a wavelength of 545.73 nm for TEM mode. For an ultra-wide bandwidth of 102 nm, the design exhibited above 99% absorbance. The proposed is wide-angle independent up to 60° for both TE and TM mode, which is useful for solar energy harvesting, solar cell, and solar thermophotovoltaics (STPV). This MMA can be used for an optical sensor or as a light detector. Moreover, this proposed design can be employed in some applications mentioned above.

Optimization of the Sensitivity of a Double-Dot Magnetic Detector

We investigate, by means of numerical simulations, the lowest magnetic field level that can be detected with a given relative accuracy with a sensor based on a double-dot device fabricated in a high-mobility two-dimensional electron gas. The double dot consists of a cavity delimited by an input and an output constriction, with a potential barrier exactly in the middle. In conditions of perfect symmetry, a strong conductance enhancement effect appears as a consequence of the constructive interference between symmetric trajectories. When the symmetry is broken, for example by the presence of an applied magnetic field, this enhancement effect is suppressed. We explore the design parameter space and assess the minimum magnetic field value that can be measured with a given accuracy in the presence of flicker noise.

Magnetic Nondestructive Testing as an Effective Instrument for Monitoring Conductors and Ground Wires of Overhead Transmission Lines

Magnetic nondestructive testing (NDT) for monitoring the equipment of overhead power lines (OHL) such as conductors, ground wires, and guy wires is discussed. Magnetic NDT allows effective testing of steel ground wires, guy wires, and steel cores of bimetallic conductors. The results of monitoring the conductors and ground wires of 35 – 220-kV OHLs in Rosseti networks are illustrated. The residual load-carrying capacity (strength) of the tested conductors and wires is estimated based on test data. It is concluded that magnetic detectors are effective in testing ground wires, guy wires, and steel cores of bimetallic conductors.

Time Projection Chamber as Inner Tracker for Super Charm-Tau factory at BINP

At present time Budker INP is developing a Super Charm-Tau factory project, which consists of a high-luminosity collider with the luminosity of 1035 cm−2s−1 and a universal magnetic detector. The tracking system of the detector will comprise of an Inner Tracker (IT) and a Drift Chamber (DC). One of the options for IT is Time Projection Chamber (TPC). The advantages of the TPC are high spatial resolution and particle identification capabilities by registration of dE/dx losses. However, using a Time Projection Chamber implies serious challenges. For example, the TPC have to simultaneously deal with tracks from several thousands events and maintain the enormous data rate. This work describes the results of the Monte-Carlo studies of the transport characteristics in various gas mixtures proposed for TPC. Besides of this, the simulation of the ion back flow and its effect on spatial resolution will be reported.

High precision cosmic ray physics with AMS-02 on the International Space Station

The Alpha Magnetic Spectrometer (AMS-02) is a state of the art cosmic ray magnetic detector operating on the International Space Station (ISS) since May 2011, performing a continuous, direct measurement of cosmic ray flux and composition in the rigidity range, $$R=pc/Ze$$ , $$O(1 \text {GV})-O(1 \text {TV})$$ . The large statistics collected during 9 years of operation, more than $$1.5\ 10^{11}$$ particles, together with the excellent particle identification provided by the instruments, allow for the precise study of the spectra of all cosmic ray species ( $$p, He, Li, Be, B, C, N, O \dots $$ and $$e^-$$ ), and begins the exploration of the rare antimatter components ( $$\bar{p}, e^+, \bar{D}, \bar{^3He},\bar{^4He} \dots $$ ), which can be used as probes to search for new physics phenomena. We review the results obtained from the data collected so far, the perspectives of the ongoing analyses and of the forthcoming 10 years of data taking on the ISS.

The High-Resolution Three-Dimensional Magnetic Detector System 3D-Magma Accurately Measures Gastric and Small Bowel Motility in People with Type 2 Diabetes with Neuropathy.

Gastroparesis is an important complication of diabetes. Motility disorders are underdiagnosed and can lead to unexplained hypoglycemia. Currently diagnostic options are limited. All established methods harbor certain disadvantages. The 3D-MAGMA system is capable of reliably measuring gastric and small intestinal motility. The aim of the current study was to determine if 3D-MAGMA is able to detect changes in intestinal motility in people with type 2 diabetes. 18 healthy volunteers and 19 people with type 2 diabetes underwent motility testing by 3D-MAGMA. In the control group the retention time in the stomach was 33.0 [min] compared to 75.3 [min] in the diabetes group. The median time in the duodenum was 12.7 [min] compared to 8.1 [min]. The time for the first 50 cm of the jejunum was 29.9 [min] compared to 28.2 [min]. Discussion and conclusion: 3D-MAGMA is able to detect changes in intestinal motility. Its clinical value might be useful in patients with fluctuating blood glucose levels and unexplained hypoglycemic episodes.

STUDY ON THE CHARACTERISTICS OF MAGNETIC MEMORY SIGNALS AT FERROMAGNETIC MATERIAL DEFECTS

In order to study the effect of defects on the surface magnetic field of specimen, a series of stepwise loading tensile tests were carried out on 30Cr alloy steel. Defects were artificially prefabricated in advance on the surface of specimens. The magnetic field signal was collected by a TSC-1M-4 magnetic detector and the characteristics of magnetic field signals were studied. It shows that the tangential magnetic field is more sensitive to the local yield of specimen. The surface magnetic memory signal changes significantly at the edge of defects. Thus, it is an feasible method to evaluate the state of stress concentration by surface magnetic memory signal.

Self-Protecting HTS Current Lead-Demonstration of a New Technology

A straight forward solution to reduce the heat load of Current Leads to superconducting magnets operating at 4 K is the use of high temperature superconductors (HTS) thereby eliminating the ohmic heating at the range below 50–77 K. The heat input from the current leads is then determined by heat conduction in the HTS section only, leading to some factor 10 reduction in the heat load in comparison to fully normal conducting conventional leads. Modern HTS conductors demonstrate extremely high current density and further decrease of the current lead heat load is limited not by the material properties but by the requirement of robustness and reliable protection of the leads in the case of cryogenic failures in order to avoid lead burnout. While accelerator magnets are designed for a fast dump at quench events within a fraction of a second, larger stored energy magnets like detector magnets may have discharge times of tens of seconds or even more. In this case the HTS part of the lead has to withstand the ohmic heating for a relatively long time and this requirement then determines the heat input at operation conditions. A new idea to reduce the heat load while keeping full reliability of the HTS leads is using a thermo-mechanical switch that is connected electrically in parallel to the HTS lead section. In the case of a quench in the HTS lead section, by using the differential thermal expansion between materials, the switch turns on and the overheated section is bypassed by the high cross-section of the conductive part of the switch. We wish to use this new technology for the first time for the BabyIAXO detector magnet. In this paper the design and test of the first and unique Self-Protecting HTS Current Lead with a current rating of 800 A is presented.

Metody geofizyczne w procesie poszukiwania ukrytych zwłok

In this article, the author presents how to use geophysical research to look for corpses. During the search, the following methods can be used: GPR, magnetic and metal detector, which assists in the detection of graves and mass graves. Research can be con-ducted as part of forensic archaeology and prosecutor’s proceedings. This article presents the possibilities and limitations of these methods.

Design of the BabyIAXO Superconducting Detector Magnet

Searching for axion like particles is one of the top priorities in particle physics. Using helioscopes is a promising technology to detect solar axions. In order to ensure readiness of the technology required for the International Axion Observatory (IAXO), the state-of-the-art facility in the field, a smaller scale but fully functional 10 m long twin bore demonstrator called BabyIAXO is prepared for construction in the early 2020s. Similar to IAXO, the two magnet bores have to point to the sun and thus to rotate 360° horizontally and ±25° vertically. The 50 MJ detector magnet of BabyIAXO is based on a common-coil layout, comprising two flat racetrack coils of 10 m length spaced by 0.8 m. Using Al-stabilized Rutherford cable with 8 NbTi strands of 1.4 mm diameter, the system can operate at 9.8 kA nominal current with 2 K temperature margin, while producing 2.0 T in the center of detection bores and 3.2 T peak field. The magnet may operate in persistent mode by using a thermally activated switch made of NbTi/CuNi matrix wire. The current leads are “over-current” designed in order to reduce the associated heat load during charging and long idle periods at full current. Uniquely, a group of two 1-stage GM and three 2-stage pulse-tube (PT) cryocoolers is used for precooling and maintaining 4.5 K in the coils. Two cryocirculators are used to transfer efficiently the available cooling capacity among the cold mass, thermal shield and current leads. While using “dry” cooling conditions, this cryogenic setup ensures cooling down the 15 t cold mass in 18 days. The relevance of design, construction, and operational experience gained with BabyIAXO for a fully fletched IAXO system is discussed.

Compression and thermal conductivity tests of Cryogel® Z for use in the ultra-transparent cryostats of FCC detector solenoids

The Future Circular Collider (FCC) study includes the design of the detector magnets for the FCC-ee+ (electron-positron) collider, requiring a 2 T solenoid for particle spectrometry, and for the FCC-hh (proton-proton) collider, with a 4 T detector solenoid. For both solenoids and their cryostats, CERN is developing an innovative and challenging design in which the solenoids are positioned inside the calorimeters, directly surrounding the inner tracker. For this purpose, the cryostats must be optimized to have maximum radiation transparency. They are structured as a sandwich of thinnest possible metallic shells for achieving vacuum tightness, supported by layers of low density and highly radiation transparent insulation material, still providing sufficient mechanical resistance and low thermal conductivity. In this respect, thermal and mechanical analysis of innovative insulation materials are currently being carried out. The first material of interest, Cryogel® Z, is shaped as a flexible composite blanket, which combines silica aerogel with reinforcing fibers and a density of 160 kg/m3. It allows a 4 m bore, 6 m long FCC-ee+ detector solenoid cryostat with a total thickness of 250 mm. CERN has investigated the compression of Cryogel® Z under 1 bar equivalent mechanical load and its thermal conductivity between 10 K and room temperature, as well as the critical phenomena of thermal shrinkage and outgassing. We present the test results, as a first overview on the material.

Significant Non-Bias-Field Magnetoelectric Response and High Output Power in a Novel Combination Based on Terfenol-D and Electrets

A new magnetoelectric (ME) sensing combination based on a magnetostrictive Terfenol-D rod and electret membrane has been proposed. AC signal and dc bias magnetic field dependences of the induced ac voltage were investigated using the traditional dynamic ME measurement. The results show that the induced ac voltage is strongly dependent on the applied ac signal and dc bias magnetic field. A significant ME response with high sensitivity and high tunability was obtained, and the optimized ME voltage output with high output power is observed for a zero bias dc magnetic field. The minimum limit of detection and maximum dc bias field tunability are 0.056 mA (or 5.27 $\times \,\,10^{-{7}}$ T) and 98.42%, respectively. In addition, both the induced ac voltage and output power are strongly dependent on the frequency of the driving ac signal magnetic field. A wide working frequency range and high energy conversion efficiency are observed with this combination. These findings not only provide insight into the dynamic measurement of ME response beyond ME materials but also provide a new type of sensing combination, possessing potential application in ME sensors, energy converters, switches, and magnetic detectors.

A New Measurement of the 60 keV Emission from Am-241 Using Metallic Magnetic Calorimeters

We report a new measurement of the 60 keV transition from 241Am. It uses a metallic magnetic calorimeter gamma-ray detector calibrated in the region around 60 keV by four accurately known X-rays and gamma rays from the decay of 169Yb. We determine an energy of 59,539.3 ± 0.3 (stat) ± 0.3 (syst) eV, which is 1.6 ± 0.4 eV lower than the current literature value of 59,540.9 ± 0.1 eV. We discuss the sources of this uncertainty and approaches to address them.

Position-Sensitive Magnetic Calorimeters for Lynx

We describe the performance of position-sensitive metallic magnetic calorimeter X-ray detectors for potential future astrophysics missions, such as Lynx. The motivation behind this is to achieve a large focal plane area by increasing the number of pixels compared to the number of readout channels (called hydra). The detector consists of a $$5 \times 5$$ array of gold absorbers thermally coupled to a paramagnetic sensor. Since each absorber has a different thermal link to the sensor, it generates a different pulse shape and enables discrimination of pixel position. Recently, we have been successfully able to discriminate 25 averaged pulse shapes by means of rise-time and pulse height. The measured pulse shapes and distribution agree well with the modeling results. The estimated energy resolutions based on the pulse height and noise data we measured are 2.8–3.7 eV for $$\hbox {MnK}\alpha $$ X-ray photons at 50 mK.