J. Borg

We present the Migdal In Galactic Dark mAtter expLoration (MIGDAL) experiment aiming at the unambiguous observation and study of the so-called Migdal effect induced by fast-neutron scattering. It is hoped that this elusive atomic process can be exploited to enhance the reach of direct dark matter search experiments to lower masses, but it is still lacking experimental confirmation. Our goal is to detect the predicted atomic electron emission which is thought to accompany nuclear scattering with low, but calculable, probability, by deploying an Optical Time Projection Chamber filled with a low-pressure gas based on CF$_4$. Initially, pure CF$_4$ will be used, and then in mixtures containing other elements employed by leading dark matter search technologies -- including noble species, plus Si and Ge. High resolution track images generated by a Gas Electron Multiplier stack, together with timing information from scintillation and ionisation readout, will be used for 3D reconstruction of the characteristic event topology expected for this process -- an arrangement of two tracks sharing a common vertex, with one belonging to a Migdal electron and the other to a nuclear recoil. Different energy-loss rate distributions along both tracks will be used as a powerful discrimination tool against background events. In this article we present the design of the experiment, informed by extensive particle and track simulations and detailed estimations of signal and background rates. In pure CF$_4$ we expect to observe 8.9 (29.3) Migdal events per calendar day of exposure to an intense D-D (D-T) neutron generator beam at the NILE facility located at the Rutherford Appleton Laboratory (UK). With our nominal assumptions, 5$\sigma$ median discovery significance can be achieved in under one day with either generator.

SKIROC2_CMS is a chip derived from CALICE SKIROC2 that provides 64 channels of low noise charge preamplifiers optimized for 50 pF pin diodes and 10 pC dynamic range. They are followed by high gain and low gain 25 ns shapers, a 13-deep 40 MHz analog memory used as a waveform sampler at 40 MHz. and 12-bit ADCs. A fast shaper followed by discriminator and TDC provide timing information to an accuracy of 50 ps, in order to test TOT and TOA techniques at system level and in test-beam. The chip was sent to fabrication in January 2016 in AMS SiGe 0,35 μm and was received in May. It was tested in the lab during the summer and will be mounted on sensors for beam-tests in the fall.

The SoLid experiment, short for Search for Oscillations with a Lithium-6 detector, is a new generation neutrino experiment which tries to address the key challenges for high precision reactor neutrino measurements at very short distances from a reactor core and with little or no overburden. The primary goal of the SoLid experiment is to perform a precise measurement of the electron antineutrino energy spectrum and flux and to search for very short distance neutrino oscillations as a probe of eV-scale sterile neutrinos. This paper describes the SoLid detection principle, the mechanical design and the construction of the detector. It then reports on the installation and commissioning on site near the BR2 reactor, Belgium, and finally highlights its performance in terms of detector response and calibration.

In this document, we present the Technical Design Report of the Upgrade of the T2K Near Detector ND280. The goal of this upgrade is to improve the Near Detector performance to measure the neutrino interaction rate and to constrain the neutrino interaction cross-sections so that the uncertainty in the number of predicted events at Super-Kamiokande is reduced to about 4%. This will allow to improve the physics reach of the T2K-II project. This goal is achieved by modifying the upstream part of the detector, adding a new highly granular scintillator detector (Super-FGD), two new TPCs (High-Angle TPC) and six TOF planes. Details about the detector concepts, design and construction methods are presented, as well as a first look at the test-beam data taken in Summer 2018. An update of the physics studies is also presented.

Abstract As part of its HL-LHC upgrade program, the CMS collaboration is developing a High Granularity Calorimeter (CE) to replace the existing endcap calorimeters. The CE is a sampling calorimeter with unprecedented transverse and longitudinal readout for both electromagnetic (CE-E) and hadronic (CE-H) compartments. The calorimeter will be built with ∼30,000 hexagonal silicon modules. Prototype modules have been constructed with 6-inch hexagonal silicon sensors with cell areas of 1.1 cm 2 , and the SKIROC2-CMS readout ASIC. Beam tests of different sampling configurations were conducted with the prototype modules at DESY and CERN in 2017 and 2018. This paper describes the construction and commissioning of the CE calorimeter prototype, the silicon modules used in the construction, their basic performance, and the methods used for their calibration.

Bent silicon crystals mounted on high-accuracy angular actuators were installed in the CERN Super Proton Synchrotron (SPS) and extensively tested to assess the feasibility of crystal-assisted collimation in circular hadron colliders. The adopted layout was exploited and regularly upgraded for about a decade by the UA9 Collaboration. The investigations provided the compelling evidence of a strong reduction of beam losses induced by nuclear inelastic interactions in the aligned crystals in comparison with amorphous orientation. A conceptually similar device, installed in the betatron cleaning insertion of CERN Large Hadron Collider (LHC), was operated through the complete acceleration and storage cycle and demonstrated a large reduction of the background leaking from the collimation region and radiated into the cold sections of the accelerator and the experimental detectors. The implemented layout and the relevant results of the beam tests performed in the SPS and in the LHC with stored proton and ion beams are extensively discussed.

Abstract The upgrade of the CMS experiment for the high luminosity operation of the LHC comprises the replacement of the current endcap calorimeter by a high granularity sampling calorimeter (HGCAL). The electromagnetic section of the HGCAL is based on silicon sensors interspersed between lead and copper (or copper tungsten) absorbers. The hadronic section uses layers of stainless steel as an absorbing medium and silicon sensors as an active medium in the regions of high radiation exposure, and scintillator tiles directly read out by silicon photomultipliers in the remaining regions. As part of the development of the detector and its readout electronic components, a section of a silicon-based HGCAL prototype detector along with a section of the CALICE AHCAL prototype was exposed to muons, electrons and charged pions in beam test experiments at the H2 beamline at the CERN SPS in October 2018. The AHCAL uses the same technology as foreseen for the HGCAL but with much finer longitudinal segmentation. The performance of the calorimeters in terms of energy response and resolution, longitudinal and transverse shower profiles is studied using negatively charged pions, and is compared to GEANT4 predictions. This is the first report summarizing results of hadronic showers measured by the HGCAL prototype using beam test data.

We present an ultrasonic transducer interface IC that includes an 8-bit, 40 V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">pp</sub> , 400 mA current output DAC for arbitrary waveform transducer excitation and a ±25 V analog multiplexer. The IC was fabricated using a 0.35 μm, 50 V CMOS process. The design eliminates the need for an external power amplifier as the piezoelectric transducer is driven directly from a segmented push-pull current output DAC, which simplifies the overall system design. This approach has the advantage of simple and rapid glitch-free power-up/down, which is especially important in integrated high-output-power drivers. The DAC has been evaluated when operating at a 150 MHz sampling rate with a ±400 mA output current and a 50 Ω load. Measured performance includes 37 dB SNDR and 46 dB SFDR at 10 MHz output frequency. By implementing an additional reference DAC and extending the receiver isolation switch into an analog multiplexer, we enable on-line calibration for the purpose of reducing the driver and receiver signal path uncertainty. Measurements show a greater than ten-fold improvement in delay uncertainty to approximately 20 ps for temperature variations of 0 to 70 degrees Celsius.

A theoretical model for diode-connected MOS transistors with a threshold cancellation technique is developed. The model is based on a detailed analysis of the technique with internal threshold cancellation (ITC) and reveals design insight and performance limitations. Derived design equations illustrate the tradeoff between the voltage drop and the reverse leakage of the diode. Furthermore, a design procedure for the optimization of the power conversion efficiency (PCE) of a bridge rectifier with ITC MOS diodes was developed based on the model. A rectifier was designed and implemented in an austriamicrosystems 0.35-μm CMOS process, and Cadence simulation results of the PCE and the voltage conversion efficiency show good agreement with the model.

Abstract The Compact Muon Solenoid collaboration is designing a new high-granularity endcap calorimeter, HGCAL, to be installed later this decade. As part of this development work, a prototype system was built, with an electromagnetic section consisting of 14 double-sided structures, providing 28 sampling layers. Each sampling layer has an hexagonal module, where a multipad large-area silicon sensor is glued between an electronics circuit board and a metal baseplate. The sensor pads of approximately 1.1 cm 2 are wire-bonded to the circuit board and are readout by custom integrated circuits. The prototype was extensively tested with beams at CERN's Super Proton Synchrotron in 2018. Based on the data collected with beams of positrons, with energies ranging from 20 to 300 GeV, measurements of the energy resolution and linearity, the position and angular resolutions, and the shower shapes are presented and compared to a detailed Geant4 simulation.

A charged particle telescope has been deployed for data taking at high rates in a CERN beam line using protons and other particles. The apparatus has a baseline of approximately 10 m in each arm, and achieves an angular resolution of 5.4 μrad using 400 GeV/c protons. The electronic readout and data acquisition system is based on that developed for the CMS Tracker, and provides almost deadtime-free operation at trigger rates of up to about 10 kHz. The telescope was developed to characterize crystals used in channeling experiments with a primary objective to validate them for use in a future LHC beam collimation system. The telescope has also been used for other studies of fundamental phenomena associated with the channeling process. The telescope is described, and its measured performance, referring to results from channeling studies, including recent measurements in heavy ion beams.

The response and the reaction of the brain system to hypoxia is a vital research subject that requires special instrumentation. With this research subject in focus, a new multifunctional lab-on-a-chip (LOC) system with control over the oxygen content for studies on biological cells was developed. The chip was designed to incorporate the patch clamp technique, optical tweezers and absorption spectroscopy. The performance of the LOC was tested by a series of experiments. The oxygen content within the channels of the LOC was monitored by an oxygen sensor and verified by simultaneously studying the oxygenation state of chicken red blood cells (RBCs) with absorption spectra. The chicken RBCs were manipulated optically and steered in three dimensions towards a patch-clamp micropipette in a closed microfluidic channel. The oxygen level within the channels could be changed from a normoxic value of 18% O 2 to an anoxic value of 0.0-0.5% O 2. A time series of 3 experiments were performed, showing that the spectral transfer from the oxygenated to the deoxygenated state occurred after about 227 ± 1 s and a fully developed deoxygenated spectrum was observed after 298 ± 1 s, a mean value of 3 experiments. The tightness of the chamber to oxygen diffusion was verified by stopping the flow into the channel system while continuously recording absorption spectra showing an unchanged deoxygenated state during 5400 ± 2 s. A transfer of the oxygenated absorption spectra was achieved after 426 ± 1 s when exposing the cell to normoxic buffer. This showed the long time viability of the investigated cells. Successful patching and sealing were established on a trapped RBC and the whole-cell access (Ra) and membrane (Rm) resistances were measured to be 5.033 ± 0.412 M Ω and 889.7 ± 1.74 M Ω respectively.

Abstract The CMS experiment at the CERN LHC will be upgraded to accommodate the 5-fold increase in the instantaneous luminosity expected at the High-Luminosity LHC (HL-LHC) [1]. Concomitant with this increase will be an increase in the number of interactions in each bunch crossing and a significant increase in the total ionising dose and fluence. One part of this upgrade is the replacement of the current endcap calorimeters with a high granularity sampling calorimeter equipped with silicon sensors, designed to manage the high collision rates [2]. As part of the development of this calorimeter, a series of beam tests have been conducted with different sampling configurations using prototype segmented silicon detectors. In the most recent of these tests, conducted in late 2018 at the CERN SPS, the performance of a prototype calorimeter equipped with ≈12,000 channels of silicon sensors was studied with beams of high-energy electrons, pions and muons. This paper describes the custom-built scalable data acquisition system that was built with readily available FPGA mezzanines and low-cost Raspberry Pi computers.

This paper presents an architecture and achievable performance for a time-to-digital converter, for 3D time-of-flight cameras. This design is partitioned in two levels. In the first level, an analog time expansion, where the time interval to be measured is stretched by a factor <i>k</i>, is achieved by charging a capacitor with current <i>I</i>, followed by discharging the capacitor with a current <i>I</i>/<i>k</i>. In the second level, the final time to digital conversion is performed by a global gated ring oscillator based time-to-digital converter. The performance can be increased by exploiting its properties of intrinsic scrambling of quantization noise and mismatch error, and first order noise shaping. The stretched time interval is measured by counting full clock cycles and storing the states of nine phases of the gated ring oscillator. The frequency of the gated ring oscillator is approximately 131 MHz, and an appropriate stretch factor <i>k</i>, can give a resolution of &asymp; 57 ps. The combined low nonlinearity of the time stretcher and the gated ring oscillator-based time-to-digital converter can achieve a distance resolution of a few centimeters with low power consumption and small area occupation. The carefully optimized circuit configuration achieved by using an edge aligner, the time amplification property and the gated ring oscillator-based time-to-digital converter may lead to a compact, low power single photon configuration for 3D time-of-flight cameras, aimed for a measurement range of 10 meters.

We present the experimental observation of the reduction of multiple scattering of high-energy positively charged particles during channeling in single crystals. According to our measurements the rms angle of multiple scattering in the plane orthogonal to the plane of the channeling is less than half that for non-channeled particles moving in the same crystal. In the experiment we use focusing bent single crystals. Such crystals have a variable thickness in the direction of beam propagation. This allows us to measure rms angles of scattering as a function of thickness for channeled and non-channeled particles. The behaviour with thickness of non-channeled particles is in agreement with expectations whereas the behaviour of channeled particles has unexpected features. We give a semi-quantitative explanation of the observed effect.

At large accelerators, bent crystals are employed to deflect weakly divergent proton beams at the stages of extraction and collimation. We demonstrate that a divergent particle beam may be efficiently deflected using a crystal with a focusing entry face. A 180 GeV/c pion beam with divergence near 0.060 mrad, which exceeds the Lindhard angle by a factor of 4, has been experimentally deflected by 0.25 mrad with efficiency near 22%. The proposed focusing crystal may serve as an element of a novel particle optics for secondary-particle beams in the TeV energy region.

We present the results of an experimental study of multiple scattering of positively charged high energy particles in bent samples of monocrystalline silicon. This work confirms the recently discovered effect of a strong reduction in the rms multiple scattering angle of particles channeled in the silicon (111) plane. The effect is observed in the plane orthogonal to the bending plane. We show in detail the influence of angular constraints on the magnitude of the effect. Comparison of the multiple scattering process at different energies indicates a violation of the law of inverse proportionality of the rms angle of channeled particles with energy. By increasing the statistics, we have improved the results of multiple scattering measurements for particles moving, but not channeled, in silicon crystals.

Ultrasonic transit-time flow-meters estimate fluid or gas flows from the difference in times of flight of upstream and downstream acoustic pulses. However, any delay differences arising from sources other than the flow to be measured will cause a troublesome "zero flow" offset error. In theory, the transducers used in the measurement system should not influence the zero flow error, as electroacoustic systems based on piezoelectric transducers have been shown to be reciprocal (when the media is stationary). However, care is required when designing the electrical interfaces for the piezoelectric transducers, if reciprocity in the system is to be utilized. This work presents technique and measurements that apply reciprocity to an ultrasonic transit-time flow-meter. Specialized electrical transducer interfaces with options to drive the transducers from either low or high impedance sources were used. Combined with a high-impedance receive mode these options made it possible to change the conditions for reciprocity in the system. We show reduced delay difference in 9 cases out of 10 when trying to utilize the reciprocal property compared to when we disregard it in favor for larger excitation energy. The delay improvements were accompanied by reduced differences between the center frequencies of the signals from the two paths

The design of a 450nW bandgap temperature sensor in the 0 to 175°C range is presented. The design demonstrates a leakage current compensation technique that is useful for low-power designs where transistor performance is limited. The technique mitigates the effects of leakage in Brokaw bandgap references by limiting the amount of excess current that is entering the bases of the main bipolar pair due to leakage. Using this technique, Monte Carlo simulations show an improvement factor of 7.6 for the variation of the temperature sensitivity over the full temperature range. For the variation of the reference voltage, Monte Carlo simulations show an improvement factor of 2.3. Sensors built using this technique can be used to accurately monitor the temperature of power semiconductors since wireless temperature sensors become feasible with sufficiently low power consumption.

In this letter, we present the results from a series of single-photon avalanche diode (SPAD) structures implemented in a commercial 0.18-μm CMOS process intended for CMOS image sensors. Variations without any effect on the performance and variations that produced non-functional devices are described. Devices based on the p+/n-well and deep-n-well/p-doped epitaxial (P-EPI) SPADs' junctions were found to work well in this process. When biased for 10% quantum efficiency, the best 10-μm diameter p+/n-well SPADs exhibited a dark count rate (DCR) of ~1 kHz, whereas the DCR of the deep-n-well/ P-EPI SPADs was only 10 Hz under the same conditions. We also show that the former type exhibited local sensitivity variations within the SPADs ranging from a factor 4 at low excess voltage to 1.2 at an excess voltage of ~0.5 V. No significant sensitivity variations were found for the deep-n-well/P-EPI SPADs, but they were found to exhibit a significant sensitivity outside the central junction, contributing from 8.3% at low excess voltage to ~70% at high excess voltage.

This paper analyses leakage current compensation techniques for low-power, bandgap temperature sensors. Experiments are conducted for circuits that compensate for collector-substrate, collector-base, body-drain and source-body leakage currents in a Brokaw bandgap sensor. The sensors are characterised and their failure modes are analysed at temperatures from 60 to $$230^{\,\circ }\hbox {C}$$ . It is found that the most appropriate compensation circuit depends on the accuracy requirements of the application and on whether a stable reference voltage is required by other parts of the circuit. Experiments show that the power consumption is dominated by leakage current at high temperatures. One type of sensor was seen to consume 260 nW at $$60 ^{\,\circ }\hbox {C}$$ , $$2.1\, \upmu \hbox {W}$$ at $$200^{\,\circ }\hbox {C}$$ and $$14\, \upmu \hbox {W}$$ at $$230^{\,\circ }\hbox {C}$$ . This work is motivated by the need to accurately monitor the temperature of power semiconductors in order to predict emerging faults in power semiconductor modules, a task for which cheap, single-chip, low-power, high-temperature, wireless bandgap temperature sensors are appropriate.

[1] This paper presents simulations and methods developed to investigate the feasibility of using a Fractional-Sample-Delay (FSD) system in the planned EISCAT_3D incoherent scatter radar. Key requirements include a frequency-independent beam direction over a 30 MHz band centered around 220 MHz, with correct reconstruction of pulse lengths down to 200 ns. The clock jitter from sample to sample must be extremely low for the integer sample delays. The FSD must also be able to delay the 30 MHz wide signal band by 1/1024th of a sample without introducing phase shifts, and it must operate entirely in baseband. An extensive simulation system based on mathematical models has been developed, with inclusion of performance-degrading aspects such as noise, timing error, and bandwidth. Finite Impulse Response (FIR) filters in the baseband of a band-pass-sampled signal have been used to apply true time delay beamforming. It has been confirmed that such use is both possible and well behaved. The target beam-pointing accuracy of 0.06° is achievable using optimized FIR filters with lengths of 36 taps and an 18 bit coefficient resolution. Even though the minimum fractional delay step necessary for beamforming is ∼13.1 ps, the maximum sampling timing error allowed in the array is found to be σ ≤ 120 ps if the errors are close to statistically independent.

The CBC3 is the latest version of the CMS Binary Chip ASIC for readout of the outer radial region of the upgraded CMS Tracker at HL-LHC.This 254-channel, 130nm CMOS ASIC is designed to be bump-bonded to a substrate to which sensors will be wire-bonded.It will instrument double-layer 2S-modules, consisting of two overlaid silicon microstrip sensors with aligned microstrips.On-chip logic identifies first level trigger primitives from high transversemomentum tracks by selecting correlated hits in the two sensors.Delivered in late 2016, the CBC3 has been under test for several months, including X-ray irradiations and SEU testing.Results and performance are reported.

A concept for doing accurate monitoring of temperature in power semiconductor modules is proposed. The concept involves glueing wireless single-chip temperature sensors with on-chip coils in direct contact with power semiconductor devices within their modules. Direct contact results in accurate temperature measurements while wireless technology such as RFID provides galvanic isolation from the power devices. An overview of the electromagnetic situation within wire bond power semiconductor modules is presented and a prototype chip with an on-chip coil has been manufactured as an initial attempt to investigate the feasibility of the concept. Measurements on said chip provides some insight in the challenges in on-chip coil designs. The feasibility of the concept is supported by earlier work that have demonstrated high power transfer efficiencies and a low power temperature sensor that is able to operate at high temperatures.

Experimental results on deflection of a 180 GeV/c π+-meson beam by a 23 mm long bent silicon crystal are analyzed to study the dechanneling process of particles due to multiple scattering. A new approach for the determination of contributions from atomic nuclei and electrons to the multiple scattering using the experimental data for random crystal orientations is suggested. The results of simulations performed using this approach, in which the contribution from atomic electrons is considered according to the prescription of Bethe, are in a good agreement with the experiment.

Strong reduction of multiple scattering for channeled particles has been observed in an experiment on the deflection of a 180 GeV/c π+-meson beam by bent silicon crystals. The RMS deflections due to multiple scattering for the channeled particles were about six times smaller than for non-channeled ones. It was shown that the approach suggested recently for the description of multiple scattering for channeled particles using the experimental data for random crystal orientations gives fair agreement with the experiment.

A bridge rectifier based on the cross-connected NMOS-PMOS bridge that avoids the inherent degradation of power conversion efficiency for increasing input levels is presented. Instead of PMOS switches, the proposed rectifier uses diode-connected MOS transistors with static threshold cancellation and minimised diode reverse leakage. With a simple and power efficient circuit solution the new rectifier allows for low-power, passive tag implementation in standard CMOS for both LF and HF RFID applications. Simulation results of the proposed rectifier in a 0.35 µm CMOS process show a power conversion efficiency over 60% for all input levels above 0.75 V with a 100 kΩ load and an input signal frequency of 13.56 MHz. The simulated DC output voltage at the same conditions is approximately V in -0.3 V. A model for the PCE of the new rectifier that includes the impact of the V th -generator is developed and compared with simulated results.

This paper presents measurements on a surface-channel charge-coupled device (CCD) with gates implemented using single-layer poly-silicon gates. The device was manufactured in a 0.18-μm pinned photodiode CMOS process available commercially from the United Microelectronics Corporation. The CCD was built with a field plate covering all gates as well as the space between them, which allows the potential in the gap between nonoverlapping gates to be manipulated. We present charge-transfer-efficiency (CTI) measurements performed at clock frequencies of 1 and 5 MHz, and at multiple background packet sizes and field-plate voltages. We further propose and apply a method for separating CTI in four-phase CCDs due to trapping from the inefficiency stemming from other phenomena. The measurements show a single-stage CTI value ranging from 1.7 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-4</sup> , with a moderate background charge and substantial field-plate voltage, to 0.007 at zero field-plate voltage and the highest background charge tested. The CTI can be reduced significantly (more than a factor of 10 in some cases) by applying a significant negative voltage at the field plate. This and the fact that only a minor part of the CTI can be attributed to trapping indicate that the performance of the device is limited by the presence of potential hollows in the gaps between the gates.

Abstract The rate of inelastic nuclear interactions in a short bent silicon crystal was precisely measured for the first time using a 180 GeV/c positive hadron beam produced in the North Experimental Area of the CERN SPS. An angular asymmetry dependence on the crystal orientation in the vicinity of the planar channeling minimum has been observed. For the inspected crystal, this probability is about $$\sim 20\%$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mo>∼</mml:mo><mml:mn>20</mml:mn><mml:mo>%</mml:mo></mml:mrow></mml:math> larger than in the amorphous case because of the atomic density increase along the particle trajectories in the angular range of volume reflection, whose dimension is determined by the crystal bending angle. Instead, for the opposite angular orientation with respect to the planar channeling, there is a smaller probability excess of $$\sim 4\%$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mo>∼</mml:mo><mml:mn>4</mml:mn><mml:mo>%</mml:mo></mml:mrow></mml:math> .

An active MOS diode for low voltage and low power RFID rectifiers is presented. The diode is based on the technique with internal threshold cancellation (ITC) for MOS diodes and uses a simple control scheme to minimize the diode reverse leakage so that full threshold cancellation is achieved. A theoretical background that illustrates the limitations with the ITC diode and a detailed presentation of the proposed diode with a short design procedure is included. The proposed diode is implemented in AMS 0.35 μm CMOS and simulated in Cadense Spectre in a single diode rectifier. With a diode voltage ranging from 50 to 100 mV, the proposed diode simultaneously demonstrates improved voltage and power conversion efficiency of more than 20 % each for frequencies up to 1 MHz, as compared to the MOS diode with internal threshold cancellation.

When deploying large antenna arrays in arctic environments, a local measurement system may be necessary in order to ensure control over the position and phase of the individual antenna elements. In this paper, a method of estimating the position and phase of each individual antenna element in the presence of mutual coupling is presented. It uses both measurements of the scattering matrix in the array and measurements of the electric field using a minimum of four probes located in the near field of the array. Simulations show that the method gives accurate results even in the presence of noise in the measurements. The geometry of the probe-array system affects the performance significantly.

The CBC3 is the latest version of the CMS Binary Chip for readout of the outer radial region of the upgraded CMS Tracker at the High Luminosity LHC. This 254-channel, 130 nm CMOS ASIC is designed to be bump-bonded to a substrate to which sensors will be wire-bonded. It will instrument double-layer 2S-modules, containing two overlaid silicon microstrip sensors, aligned with a parallel orientation. On-chip logic identifies Level-1 trigger primitives from high transverse-momentum tracks by selecting correlated clusters in the two sensors. The CBC3 was delivered in late 2016; wafer probing and performance tests have been carried out. Several prototype modules using the CBC3 have been produced and tested in the lab and in different beams. The results show that the CBC3 satisfies CMS requirements and only small corrections are needed for the final version of the chip for production.

The UA9 setup, installed in the Super Proton Synchrotron (SPS) at CERN, was exploited for a proof of principle of the double-crystal scenario, proposed to measure the electric and the magnetic moments of short-lived baryons in a high-energy hadron collider, such as the Large Hadron Collider (LHC). Linear and angular actuators were used to position the crystals and establish the required beam configuration. Timepix detectors and high-sensitivity Beam Loss Monitors were exploited to observe the deflected beams. Linear and angular scans allowed exploring the particle interactions with the two crystals and recording their efficiency. The measured values of the beam trajectories, profiles and of the channeling efficiency agree with the results of a Monte-Carlo simulation.

We study the nuclear liquid-gas phase transition on the basis of a two-component lattice gas model. A Metropolis type of sampling method is used to generate microscopic states in the canonical ensemble. The effective equation of state and fragment mass distributions are evaluated in a wide range of temperatures and densities. A definition of the phase coexistence region appropriate for small systems is proposed. The caloric curve resulting from different types of freeze-out conditions are presented.

In this document, technical details of the upgrade plan of the J-PARC neutrino beamline for the extension of the T2K experiment are described. T2K has proposed to accumulate data corresponding to $2\times{}10^{22}$ protons-on-target in the next decade, aiming at an initial observation of CP violation with $3\sigma$ or higher significance in the case of maximal CP violation. Methods to increase the neutrino beam intensity, which are necessary to achieve the proposed data increase, are described.

Abstract Beam steering performance of bent silicon crystals irradiated with high-intensity and high-energy protons has been studied. In particular, crystals of the type used for collimation and extraction purposes in the Large Hadron Collider and the Super Proton Synchrotron at CERN have been irradiated at the HiRadMat CERN facility with $$2.5 \times 10^{13}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>2.5</mml:mn><mml:mo>×</mml:mo><mml:msup><mml:mn>10</mml:mn><mml:mn>13</mml:mn></mml:msup></mml:mrow></mml:math> 440 GeV/c protons, with a pulse length of 7.2 $$\upmu $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>μ</mml:mi></mml:math> s. The purpose is to study possible changes in bending angle and channeling efficiency due to thermo-mechanical stresses in case of accidental irradiation during accelerator operations. A comparison between measurements performed before and after the irradiation does not show any appreciable performance reduction in either crystal.

In view of possible future fixed target experiments requiring precisely steered charged particle beams, the UA9 Collaboration has undertaken experimental studies of the use of bent silicon crystals for this purpose. The channeling efficiency of positively charged particles inside the crystalline lattice has been investigated in detail for a setup with a tungsten target installed in front of the crystal. Due to multiple Coulomb scattering inside the target, the channeling efficiency was observed to be reduced by a factor of about 6.1 for a 180 GeV/c quasi-parallel hadron beam. The yield of nuclear interaction secondaries as an estimation of the additional machine background is also discussed.

Experiments to measure the electric and the magnetic moments of short-lived baryons using an internal target and two bent crystals in the vicinity of one of the existing LHC detectors were recently proposed, in the frame of the Physics Beyond Colliders Working Group at CERN. Investigating fixed-target physics in the LHC with in-vacuum solid targets is an unprecedented challenge. As a preparatory step, the layout of the UA9 experiment, installed in the CERN SPS to explore beam manipulations assisted by bent crystals, has been modified to study the feasibility of the double-crystal scenario in a circular accelerator. Ideally, the first crystal should capture halo protons in channeling states directing them onto the internal target to produce rare baryons, whilst the second crystal, located just downstream of the target, should channel the baryons, rotate their polarization vector and deflect them towards the detector area. The upgraded UA9 layout is presented. Preliminary measurements providing an insight of the beam behavior are reported.

This paper presents models, circuit solutions and design procedures for maximized DC generation in inductively coupled RFID tags. An analytical model for the DC generation is derived, and relationships between the received signal in the tag coil antenna and the generated DC supply voltage using a voltage multiplier, based on both passive and active diodes, are presented. Derived from the trade-off between voltage gain in the multiplier and the tag coil at resonance, an equation for the optimum number of multiplier stages to achieve maximized DC generation is presented. Based on the derived equation, design examples are included with two typical tag coil antennas given a specification of the DC supply voltage and current. Also included in this paper is the design of a voltage multiplier based on active diodes implemented and manufactured in AMS 0.35 μm CMOS process. The active diodes are based on a concept of threshold cancellation of MOS diodes and make use of reverse leakage control to achieve full threshold cancellation.

When discussing powering wireless sensor network nodes, there are a few major energy consumers: communications, microcontroller and the sensor. We propose a wireless sensor network platform archite ...

This paper presents a circuit for realising a fuse-programmable capacitor on-chip. The trimming mechanism is implemented using integrated circuit fuses which can be blown in order to lower the resulting equivalent capacitance. However, for integrated circuits, the non-zero fuse resistance for active fuses and finite fuse resistance for blown fuses limit the Q factor of the resulting capacitor. In this work, we present a method on how to arrange the fuses in order to achieve maximal worst-case Q factor for the given circuit topology given the process parameters and requirements on capacitance. We also analyse and discuss the accuracy and limitations of the topology with regard to fuse resistance and parasitic elements such as bond pads.

This paper analyses the frequency limitations of an active rectifier for RFID applications that has been optimised for 13.56 MHz. The rectifier utilises an active MOS diode with threshold cancellation and a control scheme to reduce reverse leakage. The rectifier is implemented in AMS 0.35 μm CMOS and simulated in Cadence Spectre. For an input voltage of 2 V and an output current of 20 μA, a power and voltage conversion efficiency of 83 % and 89 %, respectively, are achieved at 13.56 MHz. We show that reducing the width of the main MOS transistor from 90 to 60 μm improves the upper frequency limit, but beyond 30 MHz the finite speed of the threshold cancellation control circuit limits the efficiency of the rectifier circuit.

In order to provide instantaneous three-dimensional radar measurements spanning the entire vertical extent of the ionosphere, the planned EIS-CAT_3D incoherent scatter radar system includes multiple receive-only antenna arrays, situated at 90-280 km from the main transmit/receive site. These employs band-pass sampling at 80 MHz, with the input signal spectrum contained in the 6 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> Nyquist zone. This paper presents simulations and methods used to investigate use of a post-ADC fractional-sample-delay (FSD) system necessary to perform true time-delay beam-forming. To test the feasibility and limitations of the system an extensive simulation tool has been developed. The simulation system is implemented in Matlab to provide cross-platform compatibility and can be applied to any similar system. Performance degrading aspects such as noise, jitter, bandwidth and resolution can be included in the simulations. The use of FIR-filters in the base-band of a band-pass sampled signal to apply true time-delay beam-forming is shown to be feasible

The objective of this thesis is to investigate if it is possible to use stereo vision to find and track the players and the ball during a football game. The thesis shows that it is possible to dete ...

When discussing powering wireless sensor net- work nodes, there are a few major energy consumers: com- munications, microcontroller and the sensor. We propose a wireless sensor network platform architecture minimizing the energy consumption of sensing. The architecture proposed herein is based on a reactive approach to sensing. A number of possible hardware approaches are evaluated and compared. This comparison indicates that analog storage between the sensing element and the sensor electronics can be a feasible method for reducing the energy consumption of the system.

As part of its HL-LHC upgrade program, the CMS collaboration is replacing its existing endcap calorimeters with a high-granularity calorimeter (CE). The new calorimeter is a sampling calorimeter with unprecedented transverse and longitudinal readout for both electromagnetic and hadronic compartments. Due to its compactness, intrinsic time resolution, and radiation hardness, silicon has been chosen as active material for the regions exposed to higher radiation levels. The silicon sensors are fabricated as 20 cm (8") wide hexagonal wafers and are segmented into several hundred pads which are read out individually. As part of the sensor qualification strategy, 8" sensor irradiation with neutrons has been conducted at the Rhode Island Nuclear Science Center (RINSC) and followed by their electrical characterisation in 2020-21. The completion of this important milestone in the CE's R&D program is documented in this paper and it provides detailed account of the associated infrastructure and procedures. The results on the electrical properties of the irradiated CE silicon sensors are presented.

This paper presents electromagnetic simulations of a wireless power transfer system suitable for a monitoring system for detection of solder fatigue in power semiconductor modules. Power is provided wirelessly from a printed spiral coil on a printed circuit board to a silicon chip with an on-chip coil. We use and adapt a known gradient-ascent-based optimization algorithm to obtain suitable coil geometries. For a frequency of 433 MHz, the simulations show an efficiency of -33.9 dB which we conclude is sufficient for the proposed monitoring system.

Acute hypoxia changes the redox-state of pulmonary arterial smooth muscle cells (PASMCs). This might influence the activity of redox-sensitive voltage-gated K⁺-channels (Kv-channels) whose inhibition initiates hypoxic pulmonary vasoconstriction (HPV). However, the molecular mechanism of how hypoxia-or the subsequent change in the cellular redox-state-inhibits Kv-channels remains elusive. For this purpose, a new multifunctional gas-tight microfluidic system was developed enabling simultaneous single-cell Raman spectroscopic studies (to sense the redox-state under normoxic/hypoxic conditions) and patch-clamp experiments (to study the Kv-channel activity). The performance of the system was tested by optically recording the O₂-content and taking Raman spectra on murine PASMCs under normoxic/hypoxic conditions or in the presence of H₂O₂. Oxygen sensing showed that hypoxic levels in the gas-tight microfluidic system were achieved faster, more stable and significantly lower compared to a conventional open system (1.6 ± 0.2%, respectively 6.7 ± 0.7%, n = 6, p < 0.001). Raman spectra revealed that the redistribution of biomarkers (cytochromes, FeS, myoglobin and NADH) under hypoxic/normoxic conditions were improved in the gas-tight microfluidic system (p-values from 0.00% to 16.30%) compared to the open system (p-value from 0.01% to 98.42%). In conclusion, the new redox sensor holds promise for future experiments that may elucidate the role of Kv-channels during HPV.

Abstract The channeling process in bent silicon crystals are used since '70s to manipulate beams of high energy particles. During the last decade, several studies and experiments carried out by the UA9 Collaboration at CERN demonstrated the possibility to use bent crystals for beam collimation, extraction, focusing and splitting in particle accelerators. These crystals are subject to deterioration due to the interaction of the particles with the crystal lattice, degrading the beam steering performance. For this reason, robustness tests are crucial to estimate their reliability and operational lifetime. A ∼8% of reduction in channeling efficiency on crystals irradiated with 2.5·10 21 /cm 2 thermal neutrons was measured and reported in this manuscript. Extrapolations to possible operational scenarios in high energy accelerators are also discussed.

This paper presents a discrete model of the DC charge-up phase in a single MOS diode rectifier for an inductively coupled RFID system. The model was derived for a rectifier driven by a coil antenna and with a storage capacitor connected to the output. A comparison between the model and a simulation of a rectifier implemented in a 0.35 μm CMOS process demonstrated fast and accurate modeling of the charge up-phase for both LF and HF RFID applications. The model was used to determine the relationship between the voltage induced in the coil antenna and the available chip current based on a specification for the durations of the charge-up and the data-communication phases in a typical LF RFID application.

This thesis collects the work performed by the author on electronics for measurement systems. The first part is the work performed on the EISCAT 3D ionospheric research radar, including two papers ...

In this paper the performance of passive range measurement imaging using stereo technique in real time applications is described. Stereo vision uses multiple images to get depth resolution in a similar way as Synthetic Aperture Radar (SAR) uses multiple measurements to obtain better spatial resolution. This technique has been used in photogrammetry for a long time but it will be shown that it is now possible to do the calculations, with carefully designed image processing algorithms, in e.g. a PC in real time. In order to get high resolution and quantitative data in the stereo estimation a mathematical camera model is used. The parameters to the camera model are settled in a calibration rig or in the case of a moving camera the scene itself can be used for calibration of most of the parameters. After calibration an ordinary TV camera has an angular resolution like a theodolite, but to a much lower price. The paper will present results from high resolution 3D imagery from air to ground. The 3D-results from stereo calculation of image pairs are stitched together into a large database to form a 3D-model of the area covered.

The High Granularity Calorimeter (HGCAL) is presently being designed to replace the CMS endcap calorimeters for the High Luminosity phase at LHC. It will feature six million silicon sensor channels and 52 longitudinal layers. The requirements for the frontend electronics include a 0.3 fC-10 pC dynamic range, low noise (2000 e-) and low power consumption (10 mW /channel). In addition, the HGCAL will perform 50 ps resolution time of arrival measurements to combat the effect of the large number of interactions taking place at each bunch crossing, and will transmit both triggered readout from on-detector buffer memory and reduced resolution real-time trigger data. We present the challenges related to the frontend electronics, data transmission and off-detector trigger preprocessing that must be overcome, and the design concepts currently being pursued.

The Low-Frequency Aperture Array (LFAA) and the Mid-Frequency Aperature Array (MFAA) elements of the Square Kilometre Array (SKA) will be made up of thousands of antennas spread over thousands of metres in Western Australia [1]. These distances make it difficult to study these antennas within an-echoic chambers. Furthermore, an-echoic chamber studies neglect any effects that the surrounding environment, such as the soil and the background RFI, have on the instrument. Thus, alternative methods were developed to study an antenna's radiation pattern in-situ.

The CMS Binary Chip (CBC) is a front-end ASIC to be used by the CMS tracker following its upgrade for High Luminosity LHC operation. It will instrument special silicon microstrip detectors to identify high transverse momentum particles in real time so tracking data can be used in the L1 trigger. The CBC should be robust against Single Event Upsets (SEUs). SEU rates have been measured in a series of tests in a 62 MeV proton beam. Each version of the chip has increased the digital circuitry, and hence the SEU susceptibility, and has also been subject to design improvements which affect SEU tolerance. The relevant design features are explained and SEU measurements reported. The expected SEU rates at the HL-LHC are estimated.

Abstract This paper presents a theory for the power transfer efficiency of printed circuit board coils to integrated circuit coils, with focus on load-dependence for low-power single-chip systems. The theory is verified with electromagnetic simulations modelled on a 350 nm CMOS process which in turn are verified by measurements on manufactured integrated circuits. The power transfer efficiency is evaluated by on-chip rectification of a 151 MHz signal transmitted by a spiral coil on a printed circuit board at 10 mm of separation to an on-chip coil. Such an approach avoids the influence of off-chip parasitic elements such as bond wires, which would reduce the accuracy of the evaluation. It is found that there is a lower limit for the load below which reducing the power consumption of on-chip circuits yield no increase in voltage generated at the load. For the examined process technology, this limit appears to lie around 56 k $$\Omega$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Ω</mml:mi> </mml:math> . The paper is focused on the analysis and verification of the theory behind this limit. We relate the results presented in this work to the application of wireless single-chip temperature monitoring of power semiconductors and conclude that such a system would be compatible with this limit.

This paper presents an approach for the design of a time stretcher based on charging and discharging a capacitor by currents with a ratio equal to the desired stretch factor. The stretched time interval can be measured by using a time-to-digital converter to achieve improved system resolution. Expressions for the current source output impedance and transistor area required to reach a specified linearity and matching are derived. The realization uses wide-swing current mirrors to achieve the required output impedance at an acceptable voltage swing at the capacitor. The derived expressions and the overall design are validated with schematic and extracted simulations in a 0.35 μm CMOS process technology.

This paper presents a background and an overview of the initial design considerations for phased array antenna being designed for the New Generation multi-static, incoherent-scatter radar station - EISCAT_3D - in Northern Scandinavia. Its anticipated electrical, mechanical and environmental design requirements are given both by the physics as well as by the extreme climate in the subarctic region of northern Scandinavia.

SUMMARY Variable-frequency drives (VFDs) are used for efficient control of AC motors in various electro-mechanical systems like pumps, fans, and compressors. It is expected that the use of VFD systems will increase due to their energy saving potential. However, there are certain challenges in securing continuous operation of VFDs in safety-critical systems. In a recent pre-study, based on a literature survey and interviews, three main challenges have been identified. These are, (1) New techniques for improved power semiconductor monitoring to meet rising demands on reliability when VFDs are applied in critical applications, (2) New techniques to model the electrodynamics of VFD systems to allow for EMC studies, (3) Adopting and developing international standards for software frameworks to allow for robust operation of VFD systems. These three main challenges are now addressed in a recently started multidisciplinary project including three PhD students and will continue until 2018.

Abstract This paper presents an encapsulation concept that enables the construction of small wireless measurement systems that can operate in industrial environments with ambient temperatures of up to 1200°C. To maximize operational time and minimize size, a layer of thermal insulation is combined with water absorbed in a porous material in the core of the device. The simulated operating time before all of the frozen water at 0°C has transformed into steam at 100°C when the ambient temperature of the device was 1200°C is 21 minutes for a sphere with an outer radius of 4 cm. If the outer radius is increased to 10 cm the simulated operating time increases to 125 minutes. Measurements were performed to validate the design. When a sphere with a radius of 4 cm was subjected to an oven temperature of 1200°C the device held the core temperature at or below 101°C for a total of 25 minutes. The time to reach the boiling point of the water was 9 minutes. Thereafter, the temperature was held constant at 100 +/− 1°C for an additional 16 minutes whereafter a rapid rise in temperature took place once all water had evaporated.

Vid dodnatstart av produktionsanlaggningar och drift av svaga nat eller o-drift ar frekvensomriktare som driver pumpar och flaktar kritiska komponenter. Om frekvensomriktare paverkas av storningar ...

Cloud computing beskrivs som ett paradigmskifte inom IT-branschen, cloudbaseradetjanster ar har for att stanna. En del av cloudcomputing ar cloudbaserade affarssystem.Genom att fa bade systemet och ...

Studien syftar till att belysa finanskrisens reella paverkan pa foretagens finansiella riskhantering. Lasaren ska ocksa fa en okad forstaelse for hur ett mindre antal svenska foretag hanterar sin f ...

Forfattarna har under perioden januari till augusti 2013 genomfort en systematisk kunskapsoversikt av vetenskapligt utvarderade och rapporterade empiriska studier av tillganglighet till elektronisk ...

Uppsatsen grundar sig pa mina funderingar kring amnesplanens syfte for amnet latin med allmansprakkunskap och hur det kan nas, speciellt med avseende pa vad elever maste lara sig for attkunna sagas ...

The analogue time expansion technique, where the time interval to be measured is stretched by a factor k, can be realized with current integration. This kind of time stretcher can be used as a time domain amplifier to improve the precision of the time to digital conversion. Two specific circuit techniques have been investigated for the realization of a time stretcher in a CMOS technology. A comparison has been made between a Miller and an open-loop integrator based time stretcher with respect to the available linearity, power consumption and circuit area. The simulations show that the open loop approach with carefully optimized circuit configurations may lead to a compact and low power single photon avalanche diode pixel configuration with the required time amplification property. The application field for the studied techniques in this work is the on-pixel-based time interval measurement unit in 3D time-of-flight cameras based on a 2D single photon avalanche diode array.

To study the layers of the ionosphere and also the interactions between Earth and Sun, the EISCAT association will build a three dimensional imaging radar: EISCAT3D. The infra­structure of the radar system will include 5 sites with ~10000 antenna elements each.For such arrays, the electromagnetic interaction between radiating elements (coupling effects) and the influence of the ground plane cannot be neglected. In addition, for array applications requiring a large number of elements, a process called thinning is most often applied to remove elements while maintaining much of the same characteristics for the antenna. When the density of components decreases, the coupling in the array will decrease as well.The relative position of elements doesn’t have a great influence on the performance of main beam. It has, however, on the mutual coupling that changes the input impedance of the radiators and the characteristics of the radiation pattern. The challenge is to find a layout where radiating elements will be separated enough for them not to couple but close enough to not disturb the performance of the array antenna.For the purpose of analyzing the performance of the EISCAT3D array, a simulation tool has been developed in Matlab/ Mathematica. In this initial study, thinned arrays with three types of elements: isotropic, half wavelength dipoles and an antenna element designed and simulated at Lulea Technical University are investigated. The latter element was designed with the ambition to meet the rigorous requirements put on the EISCAT3D array when deployed in the Northern part of Scandinavia in order to withstand the harsh environment. The radiation pattern of the single radiator is provided by an EM simulation tool (NEC2) andincludes the mutual coupling to identical elements. Thus, analyzing the radiation pattern of the array with Lulea elements, the mutual coupling effects are taken into consideration.In the simulations an attempt is made to, in a realistic manner and for different scanning angles, calculate per­formance indicators such as Directivity and Sidelobe level. When the main beam is directed towards the zenith, it was found that between the three elements analyzed, dipoles will result in the lowest directivity and the smallest side lobe level. The directivity of the array with isotropic elements and Lulea elements increases with a regular pattern with increasing number of elements. Between the three types of radiators, Lulea elements will results in the highest average side lobe level and the peak side lobe level gets better than isotropic elements when more than 60% of elements are active.

Efficient beamforming of phased-array antennas requires that the phase delay of each channel is accurately known. One technique for achieving this is to distribute a calibration or local-oscillator reference signal through a delay-insensitive signal distribution network. In this paper, we propose using passive hierarchical signal distribution networks to distribute such signals, a method that scales significantly better with the size of the array than existing signal distribution methods. We analyze the impact of impedance variations within the network on the phase accuracy and propose a calibration front-end architecture. This front end also enables the return loss and coupling between antennas to be monitored for diagnostic purposes. We present an implementation of this front end that was applied to a small prototype antenna array, and show that this implementation exhibited low sensitivity to delays within the calibration network, reduced the temperature-dependent phase error of the front ends substantially, and can be used for performing antenna return-loss measurements.

Uppslaget till var uppsats har framkommit som ett resultat av diskussioner mellan forfattarna och handledare. Forfattarna har alla tre en foretagsekonomisk bakgrund och har tidigare studerat de for ...

SammanfattningVarje hogskola och universitet har ett ansvar att vara oppen for alla oavsett etnisk eller social bakgrund, konstillhorighet, funktionshinder med mera vilket har fatt till foljd att K ...

Traditionally BJT or BiCMOS amplifiers have been used to achieve equivalent input noise densities of 1 nV√Hz or less, as desirable in some ultrasonic applications. Due to an increasing demand on in ...

SPICE models of a piezoelectric device and the ultrasound propagation medium can be used in a simu- lator intended for electronic circuits and IC design to make efficient system level optimizations. This paper presents the inclusion of mechanical noise in the SPICE model of an ultrasound system. The modeling of the noise is based on the mechanical thermal noise which is equivalent to elec- tronic Johnson (thermal) noise. For a system with a high-Q piezoelectric device designed into a medium-Q transducer the main energy loss, and thus also the main noise contri- bution, will occur in backing and sound propagation me- dia. Thus, the modeling of the mechanical noise is per- formed by including electrical noise generation in the re- sistors that model these media in the electrical equivalent circuit. The resulting output voltage noise follows theo- retical derivations of transducer noise as published by Far- low and Hayward. Simulations of a 4 MHz Pz27 piezo- electric disc with a diameter of 8 mm give a peak spectral noise density over1nV= p Hz, which is comparable to that

Traffen Hjorthagen ar en oppen traffpunkt for dig som fyllt 65 ar och bor pa Ostermalm. Har kan du delta i olika aktiviteter sasom sittgymnastik, ballongtraning och ipad-cafe. Kaffe finns till sjalvkostnadspris. Oppet torsdagar klockan 10-14.

The authors wish to make the following correction to our published paper [...]

In this paper, we discuss an experimental layout for the two-crystals scenario at the Super Proton Synchrotron (SPS) accelerator. The research focuses on a fixed target setup at the circulating machine in a frame of the Physics Beyond Colliders (PBC) project at CERN. The UA9 experiment at the SPS serves as a testbench for the proof of concept, which is planning to be projected onto the Large Hadron Collider (LHC) scale. The presented in the text configuration was used for the quantitative characterization of the deflected particle beam by a pair of bent silicon crystals. For the first time in the double-crystal configuration, a particle deflection efficiency by the second crystal of $0.188 \pm 3 \cdot 10^{-5}$ and $0.179 \pm 0.013$ was measured on the accelerator by means of the Timepix detector and Beam Loss Monitor (BLM) respectively. In this setup, a wide range angular scan allowed a possibility to \textit{in situ} investigate different crystal working regimes (channeling, volume reflection, etc.), and to measure a bent crystal torsion.

Tv-serien Vikings har blivit valdigt popular sedan den forst sandes i mars 2013. Vi undrar dock hur de olika folken (nordbor och engelsman) i serien framstalls i de religiosa kontakter och konflikt ...

As part of its HL-LHC upgrade program, the CMS Collaboration is developing a High Granularity Calorimeter (CE) to replace the existing endcap calorimeters. The CE is a sampling calorimeter with unprecedented transverse and longitudinal readout for both electromagnetic (CE-E) and hadronic (CE-H) compartments. The calorimeter will be built with $\sim$30,000 hexagonal silicon modules. Prototype modules have been constructed with 6-inch hexagonal silicon sensors with cell areas of 1.1~$cm^2$, and the SKIROC2-CMS readout ASIC. Beam tests of different sampling configurations were conducted with the prototype modules at DESY and CERN in 2017 and 2018. This paper describes the construction and commissioning of the CE calorimeter prototype, the silicon modules used in the construction, their basic performance, and the methods used for their calibration.

jonnyjohanssongltu.se, ugwgeiscat.se Abstract -Inorder toprovide instantaneous three- dimensional radar measurements spanning theentire vertical extent oftheionosphere, theplanned EIS- CAT_3Dincoherent scatter radarsystemincludes multiple receive-only antenna arrays, situated at90- 280kmfromthemaintransmit/receive site. These will employ band-pass sampling at80MHz,withtheinput signal spectrum contained inthe6th Nyquist zone. This paperpresents simulations andmethodsusedto investigate useofapost-ADC fractional-sample-delay (FSD)system necessary toperform truetime-delay beam-forming. Totest thefeasibility andlimitations of thesystemanextensive simulation toolhasbeen developed. Thesimulation system isimplemented in matlabtoprovide cross-platform compatibility and canbeapplied toanysimilar system. Performance degrading aspects suchasnoise, jitter, bandwidth and resolution canbeincluded inthesimulations. Theuse ofFIR-filters inthebase-band ofaband-pass sampled signal toapply truetime-delay beam-forming isshown tobefeasible.

Var undersokning syftar till att ta reda pa om de potentiella kunderna kanner till Optikhuset i Kristinehamn, undersoka vilka kriterier som ar viktiga vid val av optiker och hur viktig optikern ar ...

The first part of this thesis contains a literature study of current tuning techniques for continuous-time integrated filters. These tuning methods are characterised by which quantity they measure, ...

ABSTRACT In muscovite mica, the short tracks of low energy ions (0.2 ≥ E ≥ 3 keV/a.m.u.) with atomic numbers Z ≤ 10 can be revealed as very shallow “track-etch-pits” upon etching in a wide variety of chemical reagents. The geometrical characteristics of such etch pits when measured both before and after thermal annealing runs already allow the use of mica as an interesting detector in the unconventional range of low energy ions. The basic radiation damage mechanism responsible for the formation of the very short track of low energy ions in mica has still to be clearly identified. The direct search for similar tracks in other solid state track detectors has been unsuccessful as yet.