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The Forward Wall (FWall) detector is a segmented scintillation forward hodoscope with PMT readout. The FWall is one of the detector subsystems in the HADES experimental setup at SIS18 (GSI, Darmstadt, Germany) used for determination of the collision centrality and event plane orientation in nucleus-nucleus collisions. The quality of the FWall calibration is a crucial point for these tasks. The HADES experiment on particles production in Ag+Ag reaction at 1.23 and 1.58AGeV has been performed in 2019. FWall calibration was performed for both data sets. In this work the results of the FWall calibration at 1.58AGeV are presented.

The sensitivity of measured turbulent stresses to uncertainties in the probe geometry and calibration procedure is investigated for a cross-wire probe in a turbulent boundary layer using direct numerical simulation data. The errors investigated are guided by experiments, and to replicate the full experimental procedure, the cross-wire calibration procedure is simulated to generate a voltage-to-velocity mapping function, which is then utilised to calculate the measured velocity from simulated cross-wire voltages. We show that wire misalignment can lead to an incorrect mean wall-normal velocity and Reynolds shear stress in the near-wall region due to the presence of shear. Furthermore, we find that misalignment in the wire orientation cannot be fully accounted for through the calibration procedure, presumably due to increased sensitivity to an out-of-plane velocity component. This has strong implications if using a generic commercial cross-wire probe, since inclining these probes to gain access to the near-wall region can lead to a large error (up to 10%) in turbulent stresses and these errors can manifest in the log region and beyond to half the boundary layer thickness. For uncertainties introduced during the calibration procedure, the Reynolds shear stress is observed to exhibit an elevated sensitivity compared with other turbulent stresses. This is consistent with empirical observations where the repeatability in the Reynolds shear stress is found to be the poorest.

Reliable pressure measurements are essential in all activities of society and industry. Indeed, the concern with traceability has notably improved and has received considerable interest due to the intensification of international trade, the need for environmental issues, safety and health requirements, for example in medical instruments, as well as devices for measuring the flow of Fluids Based on the pressure change. Differential pressure sensors are widely used in fluid flow processes, such as for monitoring the flow conditions and to determine flowrate or fluid velocity (example are the Pitot tube, Venturi, orifice plate etc.). This study focused on the precise generation of differential pressures in the range of 500 kPa to 20 MPa using gas-operated twin pressure balances. The metrological characteristics of a differential pressure manometer were evaluated.

The demand for faster and more reliable measuring tasks for the control and quality assurance of modern production systems has created new challenges for the field of coordinate metrology. Thus, the search for new solutions in coordinate metrology systems and the need for the development of existing ones still persists. One example of such a system is the portable coordinate measuring machine (PCMM), the use of which in industry has considerably increased in recent years, mostly due to its flexibility for accomplishing in-line measuring tasks as well as its reduced cost and operational advantages compared to traditional coordinate measuring machines. Nevertheless, PCMMs have a significant drawback derived from the techniques applied in the verification and optimization procedures of their kinematic parameters. These techniques are based on the capture of data with the measuring instrument from a calibrated gauge object, fixed successively in various positions so that most of the instrument measuring volume is covered, which results in time-consuming, tedious and expensive verification and optimization procedures. In this work the mathematical calibration procedure of a capacitive sensor-based indexed metrology platform (IMP) is presented. This calibration procedure is based on the readings and geometric features of six capacitive sensors and their targets with nanometer resolution. The final goal of the IMP calibration procedure is to optimize the geometric features of the capacitive sensors and their targets in order to use the optimized data in the verification procedures of PCMMs.

Single-particle microbeam is uniquely capable of precisely delivering a preset number of charged particles to individual cells or sub-cellular targets to be determined in vitro. It is crucial to find a reference point that relates the microbeam's location to the microscope's plane and align individual targets at this reference point for cell irradiation. To choose an appropriate reference point, an approach based on analysing the intensity distribution of fluorescence in a thin scintillator excited by traversing particles is newly developed using the CAS-LIBB single-particle microbeam, which features decisive physical signification and sufficient resolution. As its bonus, this on-line analysis provides precise and fast response to the determination of beam profile and potentially optimizes the microbeam quality by further adjusting hardware setup.

The calibration procedure of wheel load measuring system is presented. Designed method allows estimation of selected wheel load components while the vehicle is in motion. Mentioned system is developed to determine friction forces between tire and road surface, basing on measured internal reaction forces in wheel suspension mechanism. Three strain gauge bridges and three-component piezoelectric load cell are responsible for internal force measurement in suspension components, two wire sensors are measuring displacements. External load is calculated via kinematic model of suspension mechanism implemented in Matlab environment. In the described calibration procedure, internal reactions are measured on a test stand while the system is loaded by a force of known direction and value.

British Pendulum Skid Resistance Testers are being used for the determination of the slip/skid resistance of surfaces by laboratories all around the world in different fields. The instrument itself can give reproducible results; however, the comparison of results obtained by different instruments can show large deviations. This paper presents a comparison of the performance of four pendulum testers, the investigation of requirements in international standards and the analysis of the calibration procedure for the determination of the slider force/deflection characteristics. The slider force/deflection characteristics were measured manually and also automatically with a uniaxial tensile/compression testing machine using different techniques. The results highlight the importance of the slider force/deflection characteristic shape and its influence on the results indicated by the pendulum tester and outline inconsistencies in different international standards describing the same device and its requirements. Presented results show good reproducibility and comparability of the pendulum test results when calibration is performed with the assembled pendulum either manually or automatically, provided the stricter slider force characteristic envelope requirements are taken into consideration. The actual slider force should be stable from 1.5 mm deflection onwards.

The MINOS detectors are steel-scintillator sampling tracking calorimeters and are calibrated using an in-situ light-injection system and cosmic ray muons. The MINOS Near and Far Detectors have been operating almost continuously since 2003 and 2005, providing opportunity to quantify the behavior of the various detector components, many of which are used in the next generation neutrino oscillation experiments, under long-term experimental operation. We report on the calibration procedure and its stability, as well as the time and temperature dependencies of the scintillator, wavelength-shifting fibers and photo-multiplier tubes.

A new calibration method, suitable for planar sensors and other non-coaxial devices, is presented. Assuming that the matching network of the device under test is symmetrical, simplifications are made, leading to a procedure that uses a single parallel unknown standard named TYS (thru-Y-side). The de-embedding equations are developed and the results of its application are reported, showing a bandwidth wider than thru-reflect-match. Finally, the calibration is applied to the characterization of a planar sensor and the permittivity determination of three known materials, compared with the widely used thru-reflect-line method.

In order to detect extremely weak magnetic signals, superconducting quantum interference device (SQUID) gradiometers are widely used to suppress environmental noise. A hardware SQUID gradiometer consists of a niobium gradio-antenna and an SQUID, which are coupled via an input coil. Here gradiometer imbalance may greatly reduce its noise suppression performance. The gradiometer balance depends on the geometrical forms of the antenna wound by niobium wire. We describe a simple method based on Faraday's law for the pre-calibration of the gradiometer balance at room temperature, before the gradiometer is set up. The pre-calibrating results are compared with the measured balance of an SQUID gradiometer system. This method may be used for sifting hardware gradiometers for multi-channel systems.

The barrel region of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider is instrumented with Drift Tube (DT) detectors. This paper describes in full details the calibration of the DT hit reconstruction algorithm. After inter-channel synchronization has been verified through the appropriate hardware procedure, the time pedestals are extracted directly from the distribution of the recorded times. Further corrections for time-of-flight and time of signal propagation are applied as soon as the three-dimensional hit position within the DT chamber is known. The different effects of the time pedestal miscalibration on the two main hit reconstruction algorithms are shown. The drift velocity calibration algorithm is based on the meantimer technique. Different meantimer relations for different track angles and patterns of hit cells are used. This algorithm can also be used to determine the uncertainty on the reconstructed hit position.

New electronics, including front-end and data acquisition (DAQ), has been developed and tested for a STAR time-of-flight (TOF) detector based on multi-gap resistive plate chamber (MRPC) technology. The time-over-threshold (TOT), i.e. signal width, is used for the time correction instead of the signal amplitude. Corresponding changes and implementation in the calibration method are discussed in detail. TOF data collected in RHIC 200 GeV Cu+Cu collisions are analyzed to test the performance of the detector. The time resolution is ~75?ps and it is consistent with the results in earlier RHIC runs.

An electroreflectance spectrum of the front surface of an UV enhanced silicon photodiode has been recorded in the spectral range from 300 to 500 nm. From this spectrum, the correction on the calculation of the diode absolute spectral response, due to the change in its reflectance during the 'oxide bias experiment', has been found to be no greater than 0.2%.

A photoionization chamber has been used to determine the absolute intensity of 304 AA radiation emitted during electric-field quenching of fast He+(2s) metastable ions. The measurements have been used to redetermine with greatly improved accuracy cross sections previously measured in this laboratory for formation of He+(2s) metastable ions by (a) one-electron capture in the passage of 10-60 keV 3He2+ ions through H, H2, He, Ar, Kr, K, N2 and O2 and (b) direct excitation of 6-30 keV 3He+ ions in passage through He, Ar, Kr, H2, N2 and O2. The measurements show that, while relative cross sections for the different target gases remain unchanged, previously estimated absolute values should be increased by a factor of 2.2. Cross sections revised in this way are believed to be accurate to within 15% for H2 and 20% for the other target gases.

One of the main difficulties in turbulence measurement using a yawed hot wire is the determination of the probe sensitivity to perturbations in the velocity components. Direct differentiation of the anemometer output for independent changes in two velocity components tends to be inaccurate because it makes exceptional demands on the skill of the operator and performance of the calibration equipment. A second approach is to calibrate for changes in one component only and deduce the transverse sensitivity using the measured wire inclination and an assumed law for deviations from the cosine law of cooling. However, the second method is very sensitive to errors in measurement of wire angle and formation of the cooling law. A new procedure has been devised which combines the advantages of both methods mentioned above. The method is insensitive to errors in measurement of wire angle, does not require explicit differentiation with respect to the transverse component of velocity and does not depend on the choice of a particular cooling law. The procedure is deduced via a Taylor series expansion in the deviation from a cosine law of cooling. It also allows direct use of published data for deviations from the cosine law, if the wire inclination can be specified accurately.

The system spatial resolution of whole-body positron emission tomography (PET) is limited to around 2 mm due to positron physics and the large diameter of the bore. To stay below this 'physics'-limit a scintillation detector with an intrinsic spatial resolution of around 1.3 mm is needed. Currently used detector technology consists of arrays of 2.6-5 mm segmented scintillator pixels which are the dominant factor contributing to the system resolution. Pixelated detectors using smaller pixels exist but face major drawbacks in sensitivity, timing, energy resolution and cost. Monolithic continuous detectors, where the spatial resolution is determined by the shape of the light distribution on the photodetector array, are a promising alternative. Without having the drawbacks of pixelated detectors, monolithic ones can also provide depth-of-interaction (DOI) information. In this work we present a monolithic detector design aiming to serve high-resolution clinical PET systems while maintaining high sensitivity. A 50 x 50 x 16 mm(3) Lutetium-Yttrium oxyorthosilicate scintillation crystal with silicon photomultiplier (SiPM) backside readout is calibrated in singles mode by a collimated beam obtaining a reference dataset for the event positioning. A mean nearest neighbour (MNN) algorithm and an artificial neural network for positioning are compared. The targeted intrinsic detector resolution of 1.3 mm needed to reach a 2 mm resolution on system level was accomplished with both algorithms. The neural network achieved a mean spatial resolution of 1.14 mm FWHM for the whole detector and 1.02 mm in the centre (30 x 30 mm(2)). The MNN algorithm performed slightly worse with 1.17 mm for the whole detector and 1.13 mm in the centre. The intrinsic DOI information will also result in uniform system spatial resolution over the full field of view.