Human magnetic field registration capability using low-field magnetic sensors

The aim of the study was to find out whether it is possible to detect the human magnetic field without shielding using sensors. For this, an experiment "the possibility of detecting the human magnetic field using sensors" was conducted. During the experiment it was found that with the help of a low-field magnetic detector it is possible to register a person's magnetic field, which is changing if there is a change in a heart rate. During the study, a device for recording the magnetic field of a human was assembled, a methodology for obtaining data was developed, a description of the materials and equipment used was provided. In accordance with the described methods of data collection, measurements of human magnetic field with and without load were made. The data obtained during the study were processed and the results were displayed. Based on the obtained results, an analysis was carried out, conclusions were drawn and recommendations for subsequent studies were indicated. As a result, the possibility of detecting a human's magnetic field using sensors was first studied.

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.

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.

Time measurement with the SND electromagnetic calorimeter

The SND is a non-magnetic detector deployed at the VEPP-2000 e+e− collider (BINP, Novosibirsk) for hadronic cross-section measurements in the center of mass energy range below 2 GeV. The important part of the detector is a three-layer hodoscopic electromagnetic calorimeter (EMC) based on NaI(Tl) counters. Until the recent EMC spectrometric channel upgrade, only the measurement of the energy deposition in counters was possible. New EMC signal digitizing electronics based on FADC allow us to obtain also the signal arrival time. The new electronics and supporting software, including digitized signal processing algorithms, are now used for data taking in the ongoing experiment. We discuss the amplitude and time extraction algorithms, the new system performance on experimental events and how this time measurement can be applied to physics analysis.