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In the past decades, laboratory experiments have contributed significantly to the exploration of the fundamental physics of space plasmas. Since 1908, when Birkeland invented the first terrella device, numerous experimental apparatuses have been designed and constructed for space physics investigations, and beneficial achievements have been gained using these laboratory plasma devices. In the present work, we review the initiation, development, and current status of laboratory plasma devices for space physics investigations. Ipatasertib inhibitor The notable experimental apparatuses are categorized and discussed according to the central scientific research topics they are related to, such as space plasma waves and instabilities, magnetic field generation and reconnection, and modeling of the Earth's and planetary space environments. The characteristics of each device, including the plasma configuration, plasma generation, and control method, are highlighted and described in detail. In addition, their contributions to reveal the underlying physics of space observations are also briefly discussed. For the scope of future research, various challenges are discussed, and suggestions are provided for the construction of new and enhanced devices. The objective of this work is to allow space physicists and planetary scientists to enhance their knowledge of the experimental apparatuses and the corresponding experimental techniques, thereby facilitating the combination of spacecraft observation, numerical simulation, and laboratory experiments and consequently promoting the development of space physics.We compare two different experimental techniques for the magnetic-sub-level preparation of metastable 4He in the 23S1 level in a supersonic beam, namely, magnetic hexapole focusing and optical pumping by laser radiation. At a beam velocity of v = 830 m/s, we deduce from a comparison with a particle trajectory simulation that up to 99% of the metastable atoms are in the MJ″ = +1 sub-level after magnetic hexapole focusing. link2 Using laser optical pumping via the 23P2-23S1 transition, we achieve a maximum efficiency of 94% ± 3% for the population of the MJ″ = +1 sub-level. For the first time, we show that laser optical pumping via the 23P1-23S1 transition can be used to selectively populate each of the three MJ″ sub-levels (MJ″ = -1, 0, +1). We also find that laser optical pumping leads to higher absolute atom numbers in specific MJ″ sub-levels than magnetic hexapole focusing.The vacuum ultraviolet (VUV) spectroscopy system on the Joint Texas Experimental Tokamak has been upgraded to achieve fast acquisition for the study of impurity transport in transient modulated experiments. In this upgrade, the previous high-energy charge-coupled device detector was replaced by a microchannel plate with a CsI-coated photocathode and P43 phosphor to transform the VUV light to visible light, which is then acquired by a high-speed electron-multiplying charge-coupled device. Two-stage focusing was achieved using a reference slit plate illuminated successively by a green light source and the Lyman series hydrogen spectral lines from the vacuum-conditioning plasma. The spatial resolution was evaluated as ∼4 mm based on the level of image blurring from the alignment plate. A response time of ∼2 ms was obtained with the ten-vertical-track setup.A main ion charge exchange recombination spectroscopy (mChERS) diagnostic has been developed to measure the velocity and temperature of the main deuterium ions in the C-2W (also called Norman) field-reversed configuration (FRC) device. A modulated diagnostic neutral beam (DNB) of hydrogen with 40 keV full energy and a nominal current of 8.5 A provides the charge exchange signal. The DNB can achieve a fast modulation frequency of up to 10 kHz, a rare attribute to find on other fusion devices, which defines the time resolution of mChERS. Currently, the mChERS diagnostic provides simultaneous measurements at five spatial locations in the FRC plasma using a high-speed camera. The design and capabilities of the mChERS system are presented along with first experimental data.In this paper, the pixelated phase mask (PPM) method of interferometry is applied to coherence imaging (CI)-a passive, narrowband spectral imaging technique for diagnosing the edge and divertor regions of fusion plasma experiments. Compared to previous CI designs that use a linear phase mask, the PPM method allows for a higher possible spatial resolution. The PPM method is also observed to give a higher instrument contrast (analogous to a more narrow spectrometer instrument function). A single-delay PPM instrument is introduced as well as a multi-delay system that uses a combination of both pixelated and linear phase masks to encode the coherence of the observed radiation at four different interferometer delays simultaneously. The new methods are demonstrated with measurements of electron density ne, via Stark broadening of the Hγ emission line at 434.0 nm, made on the Magnum-PSI linear plasma experiment. A comparison of the Abel-inverted multi-delay CI measurements with Thomson scattering shows agreement across the 3 × 1019 1 × 1020 m-3 only. Accurate and independent interpretation of single-delay CI data at lower ne was not possible due to Doppler broadening and continuum emission.Short current pulses are very diffuse and have also been used in many electronic devices for biological stress recently. In order to measure these current pulses, Rogowski coils are applied. In this work, we focus our efforts on the structure of the Rogowski box, which has a narrow slit, needed to correctly lead the current to be diagnosed. The attenuation coefficient depends mainly on the inductance values, the load resistance, and the virtual capacitance between coil and ground. Until now, the influence of the slit length and its width was never considered. We have studied, either theoretically or experimentally, the influence of the slit dimensions on calibration factor variations. The attenuation factor ranged from 11.3 to 16.3 A/V for s ranging from 0.8 to 0.2 mm, respectively. The device we realized is able to perform precise measurements of sub-nanosecond rise time pulses (∼100 ps).In spectroscopic experiments, data acquisition in multi-dimensional phase space may require long acquisition time, owing to the large phase space volume to be covered. In such a case, the limited time available for data acquisition can be a serious constraint for experiments in which multidimensional spectral data are acquired. Here, taking angle-resolved photoemission spectroscopy (ARPES) as an example, we demonstrate a denoising method that utilizes deep learning as an intelligent way to overcome the constraint. With readily available ARPES data and random generation of training datasets, we successfully trained the denoising neural network without overfitting. The denoising neural network can remove the noise in the data while preserving its intrinsic information. We show that the denoising neural network allows us to perform a similar level of second-derivative and line shape analysis on data taken with two orders of magnitude less acquisition time. The importance of our method lies in its applicability to any multidimensional spectral data that are susceptible to statistical noise.The very short burn time and small size of burning plasmas created at advanced laser-fusion facilities will require high-spatial-resolution imaging diagnostics with fast time resolution. These instruments will need to function in an environment of extremely large neutron fluxes that will cause conventional diagnostics to fail because of radiation damage and induced background levels. One solution to this challenge is to perform an ultrafast conversion of the x-ray signals into the optical regime before the neutrons are able to reach the detector and then to relay image the signal out of the chamber and into a shielded bunker, protected from the effects of these neutrons. With this goal in mind, the OMEGA laser was used to demonstrate high-temporal-resolution x-ray imaging by using an x-ray snout to image an imploding backlighter capsule onto a semiconductor. The semiconductor was simultaneously probed with the existing velocity interferometry system for any surface reflector (VISAR) diagnostic, which uses an optical streak camera and provided a one-dimensional image of the phase in the semiconductor as a function of time. The phase induced in the semiconductor was linearly proportional to the x-ray emission from the backlighter capsule. This approach would then allow a sacrificial semiconductor to be attached at the end of an optical train with the VISAR and optical streak camera placed in a shielded bunker to operate in a high neutron environment and obtain time-dependent one-dimensional x-ray images or time-dependent x-ray spectra from a burning plasma.A retarding potential energy analyzer was used to obtain temporally resolved ion energy distribution functions (IEDFs) of a flowing laboratory plasma. The plasma of time varying ion energy was generated at 1 and 20 kHz using a commercial gridded ion source and modulated using a wideband power amplifier. Three plasma energy modulation setpoints were tested, and their IEDFs were reconstructed. This method leverages high-speed, low-noise instrumentation to obtain fast collector current measurements at discrete retarding bias levels, recombining them in the time domain using two data fusion techniques. The first method is an empirical transfer function, which determines the linear ratio of complex coefficients in Fourier space. link3 The second method, shadow manifold interpolation, reconstructs the IEDFs point-by-point by comparing input and output datasets in a multi-dimensional phase space. Reconstructed IEDFs from the two methods are presented and compared. The two analysis methods show very good agreement.In order to supplement manufacturers' information, this department will welcome the submission by our readers of brief communications reporting measurements on the physical properties of materials, which supersede earlier data or suggest new research applications.Optical controls provided by lasers are the most important and essential techniques in trapped ion and cold atom systems. It is crucial to increase the optical accessibility of the setup to enhance these optical capabilities. Here, we present the design and construction of a new segmented-blade ion trap integrated with a compact glass vacuum cell, in place of the conventional bulky metal vacuum chamber. The distance between the ion and four outside surfaces of the glass cell is 15 mm, which enables us to install four high-numerical-aperture (NA) lenses (with two NA ⩽ 0.32 lenses and two NA ⩽ 0.66 lenses) in two orthogonal transverse directions, while leaving enough space for laser beams in the oblique and longitudinal directions. The high optical accessibility in multiple directions allows the application of small laser spots for addressable Raman operations, programmable optical tweezer arrays, and efficient fluorescence collection simultaneously. We have successfully loaded and cooled a string of 174Yb+ and 171Yb+ ions in the trap, which verifies the trapping stability. This compact high-optical-access trap setup not only can be used as an extendable module for quantum information processing but also facilitates experimental studies on quantum chemistry in a cold hybrid ion-atom system.