Lindsaymcintyre5895

The Laser Interferometer Space Antenna Pathfinder (LPF) main observable, labeled Δg, is the differential force per unit mass acting on the two test masses under free fall conditions after the contribution of all non-gravitational forces has been compensated. At low frequencies, the differential force is compensated by an applied electrostatic actuation force, which then must be subtracted from the measured acceleration to obtain Δg. Any inaccuracy in the actuation force contaminates the residual acceleration. This study investigates the accuracy of the electrostatic actuation system and its impact on the LPF main observable. It is shown that the inaccuracy is mainly caused by the rounding errors in the waveform processing and also by the random error caused by the analog to digital converter random noise in the control loop. Both errors are one order of magnitude smaller than the resolution of the commanded voltages. We developed a simulator based on the LPF design to compute the close-to-reality actuation voltages and, consequently, the resulting actuation forces. The simulator is applied during post-processing the LPF data.A new concept for a non-destructive testing device using a novel carbon nanotube (CNT) based miniature x-ray tube is proposed. The device can be used for small-scale internal inspection of objects. To investigate the effectiveness of the proposed concept, the device was fabricated and its performance was systematically analyzed. The non-destructive testing device consists of a CNT based miniature x-ray tube, a scintillator, an optical lens, and a detector. The size of the focal spot needed to identify objects as small as 5 µm was calculated through simulation. An electron optics simulation software, E-GUN, was used to optimize the geometries of both the focusing cup and the x-ray target to achieve the desired focal spot size of the x-ray tube. The CNT based miniature x-ray tube was fabricated using the brazing process, and an NdFeB focusing lens was used to further reduce the focal spot size. XR images were obtained using the fabricated device and the spatial resolutions of the images were evaluated using the modulation transfer function (MTF). The fields of view (FOVs) per probe are 7.1 mm2 and 1.8 mm2 when using a 5× optical lens and a 10× optical lens, respectively. The FOV can be increased by increasing the number of probes incorporated into the device. MTF10 values were determined to be 105 lp/mm and 230 lp/mm when using the 5× optical lens and 10× optical lens, respectively. By using an optical lens to enlarge the XR images, the effect of focal spot was minimized and clear XR images were obtained.Single-ion monitoring is a key requirement for many energetic heavy-ion experiments, e.g., the laboratory simulation of the single event effect of semiconductor devices under heavy ion bombardments. We have developed a two-dimensional position-sensitive and timing monitor of individual ions. It is composed of a thin aluminum foil, a pair of microchannel plate detectors, and electrostatic and magnetic fields. When energetic heavy ions pass through the aluminum foil, secondary electrons generated on each side of the foil are guided by the fields to the corresponding detector. Both the hitting position and the arrival time of the secondary electrons on corresponding detectors are measured in coincidence. A test with an 241Am α source shows that the present monitor is capable of discriminating true events from heavy background radiations. A position resolution of 1.0 mm and a recording time resolution of 50 ns have been realized in the test.We present an unshielded, double-resonance magnetometer in which we have implemented a feed-forward measurement scheme in order to suppress periodic magnetic noise arising from, and correlated with, the mains electricity alternating current line. The technique described here uses a single sensor to track ambient periodic noise and feed forward to suppress it in a subsequent measurement. This feed forward technique has shown significant noise suppression of electrical mains-noise features of up to 22 dB under the fundamental peak at 50 Hz, 3 dB at the first harmonic (100 Hz), and 21 dB at the second harmonic (150 Hz). This technique is software based, requires no additional hardware, and is easy to implement in an existing magnetometer.Gas sealing structures have been widely used in various engineering fields, and the gas leakage rate is one of the most important indicators for evaluating the sealing performance of sealing structures. In this paper, an aeroacoustic measurement method is proposed to measure the gas leakage rate by using one sound pressure sensor based on known location of a single leakage hole combining the aeroacoustic theory with numerical simulation results. First, the basic measurement principle is established using the Lighthill acoustic analogy method. Then, the finite element method is used to calculate the fitting parameters in leakage rate equations. Finally, the single-hole leakage experiments are carried out to verify the effectiveness of this gas leakage rate measurement method. The measurement results are in good agreement with the results recorded by flowmeters.In this work, a novel ultrasonic linear motor is proposed. The proposed motor has two driving feet and a simple structure. The torque applied to the motor is converted into a normal preload between the driving feet and the mover, avoiding the use of a large preloading mechanism. The vibration characteristics of the motor are studied by the finite element analysis method. Finally, the prototype is fabricated. The experimental system is established, and a series of experiments has been carried out to evaluate the performance of the motor in terms of maximum velocity and maximum output force, and the feasibility of the proposed motor is verified. The experimental results show that the maximum no-load velocities of the motor moving to the right and left are 85.2 mm/s and 76 mm/s, respectively, and the maximum output force is 1.96 N. The numerical simulation results show that the stator of the motor can be used as a displacement amplifying structure, which can effectively amplify one or two orders of magnitude deformation of the piezoelectric stack.Thin film thermocouples (TFTCs) are designed by finite element analysis and fabricated on the flexible substrate (polyimide) based on radio frequency magnetron sputtering technology, which can be used to measure the temperature of the curved surface. Various novel structures of TFTCs with several multi-junctions are designed to improve the stability and the reliability of measurement. The characteristics of its thermoelectric output are simulated by software. As the temperature range varies between 10 °C and 200 °C, the electromotive force behavior experiments show that the average Seebeck coefficient of the TFTCs can reach 25.8 µV/°C, the resolution of sensor is less than 0.1 °C, and the temperature drift is only 1.3%, 1.2%, 1.0% at 84 °C, 110 °C, and 142 °C, respectively. The maximum drift rate of TFTCs is 0.234 °C/min at 142 °C. The flexible TFTC temperature sensor shows great advantages in sensitivity, stability, reliability resolution, and measuring range.We review the rapid recent progress in single-photon sources based on multiplexing multiple probabilistic photon-creation events. Such multiplexing allows higher single-photon probabilities and lower contamination from higher-order photon states. We study the requirements for multiplexed sources and compare various approaches to multiplexing using different degrees of freedom.Since its invention in 1999, the optical centrifuge has become a powerful tool for controlling molecular rotation and studying molecular dynamics and molecular properties at extreme levels of rotational excitation. This technique has been applied to a variety of molecular species, from simple linear molecules to symmetric and asymmetric tops, to molecular ions and chiral enantiomers. Properties of isolated ultrafast rotating molecules, the so-called molecular superrotors, have been investigated, as well as their collisions with one another and the interaction with external fields. The ability of an optical centrifuge to spin a particular molecule of interest depends on both the molecular structure and the parameters of the centrifuge laser pulse. An interplay between these two factors dictates the utility of an optical centrifuge in any specific application. Here, we discuss the strategy of assessing and adjusting the properties of the centrifuge to those of the molecular rotors and describe two practical examples of optical centrifuges with very different characteristics, implemented experimentally in our laboratory.We present the first measurements of Hall conductivity utilizing a torque magnetometry method. A Corbino disk exhibits a magnetic dipole moment proportional to Hall conductivity when voltage is applied across a test material. This magnetic dipole moment can be measured through torque magnetometry. The symmetry of this contactless technique allows for the measurement of Hall conductivity in previously inaccessible materials. Finally, we calculate a low-temperature noise bound, demonstrate the lack of systematic errors, and measure the Hall conductivity of sputtered indium tin oxide.The energy spreads of ion beams generated from a penning ionization gauge-type ion source with electromagnets were measured using a parallel electrostatic analyzer. The ion source was developed to be installed in a mega-electron volt (MeV) compact ion microbeam system. A gaseous ion beam of expectedly high brightness and narrow energy spread was generated from the ion source to form a microbeam. To produce such an ion beam, a high-density plasma with a small volume was generated using a strong magnetic field in the ion source. The beam energy spread width was of particular importance because it forms an ion microbeam by reducing the chromatic aberration at a focusing lens. In this report, the energy spread was investigated by changing the parameters of the ion source, e.g., extraction voltage, excitation current of electromagnets, vacuum, and anode voltage. selleck chemical The investigation showed that spread widths are influenced by the extraction voltage, vacuum, and anode voltage. The minimum width of ∼5.0 ± 0.1 eV was obtained at a beam energy of 200 eV. This value is acceptable for the MeV compact ion microbeam system.Pickup spectroscopy is a means of determining the abundance, mass, charge, and lifetime of ions oscillating in electrostatic ion beam traps. Here, we present a framework for describing the harmonic height distribution of the Fourier transform of the pickup signal and discuss the importance of the pickup positioning, bunch dynamics, and pickup width on the harmonic height distribution. We demonstrate the methodology using measurements from a newly constructed electrostatic ion beam trap.We present an alternative numerical method to the Abel inversion technique, which can be applied to complex non-symmetrical systems. A comparison with the Abel inversion algorithm was conducted. For benchmarking, the method was applied to a synthetic trace representing a plasma waveguide characterized by a constant parabolic density profile. Furthermore, the temperature and refractive index of a plume of hot air surrounding a non-cylindrical soldering iron were retrieved. Temperatures between 50 °C and 200 °C were successfully retrieved within the instrument precision. The proposed method allows robust and fast data retrieval while maintaining the accuracy and resolution of well-known methods, as Abel inversion.