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The LUXE experiment is designed to explore the strong-field QED regime in interactions of high-energy electrons from the European XFEL in a powerful laser field. One of the crucial aims of this experiment is to measure the production of electron-positron pairs as a function of the laser field strength where non-perturbative effects are expected to kick in above the Schwinger limit. For the positron energy measurements and multiplicity spectra, a tracker and an electromagnetic calorimeter are foreseen. Since the expected number of positrons varies over five orders of magnitude, and has to be measured over a widely spread low energy background, the calorimeter must be compact and finely segmented. The concept of a sandwich calorimeter made of tungsten absorber plates interspersed with thin sensor planes is developed. The sensor planes comprise a silicon pad sensor, flexible kapton printed circuit planes for bias voltage supply and signal transport to the sensor edge, all embedded in a carbon fibre support. The thickness of a sensor plane is less than 1 mm. As an alternative, gallium arsenide sensors are considered with integrated readout strips. Prototypes of both sensor planes were studied in an electron beam of 5 GeV at DESY. Results from this test beam are presented on the sensor response homogeneity, edge effects, signal sharing and embedded trace effect.

The residual atmospheric muon flux was measured at a candidate site for a new underground, low-radiation physics laboratory beneath the Kokhav HaYarden national park in Israel. Located inside the tunnels of a hydroelectric pumped-storage facility, the proposed site benefits from a vertical rock overburden of 361 m, large potential floorspace, and easy access by road. A muon hodoscope of vertically stacked wide-area plastic scintillator plates was employed to measure the suppression in the integrated muon flux at the site as compared with above ground at sea level. The suppression factor is reported at 4456 ± 77 , expressed as 3.75 ± 0.2 × 10 - 6 cm - 2 s - 1 in absolute terms, corresponding to an effective overburden of roughly 873 m.w.e.. Furthermore, the asymmetric topography of the mountain above and its muon shadow are clearly visible in the angular data. Finally, auxiliary environmental measurements recorded low background radon activity at 28.3 ± 14.0 Bq m - 3 . The experimental campaign thus succeeded in demonstrating the viability of the site’s working conditions for future scientific research.

We utilise muons from cosmic ray to explore hidden underground archaeological structures. Presented here is the design, simulation studies and first laboratory results of a compact, scintillators based, cosmic ray muon telescope for underground muon radiography.

We report on studies of non-toxic scintillating liquid useful for large surface detectors. Arrays of liquid scintillators offer a rather simple tool for detecting charged particles traversing a surface and tracking their path through a defined volume. Insertion of wavelength shifting fibres along the liquid scintillating containers significantly improves the light collection at the two ends of the scintillators. We have demonstrated that we can achieve timing resolution of O(1 ns) allowing good spatial resolution. Liquid scintillators with fibres read by Photo-multipliers or SiPMs provide an inexpensive alternative technology which suits well the requirement of the MATHUSLA experiment tracking system.

We report on studies of non-toxic scintillating liquid useful for large surface detectors. Arrays of liquid scintillators offer a rather simple tool for detecting charged particles traversing a surface and tracking their path through a defined volume. Insertion of wavelength shifting fibres along the liquid scintillating containers significantly improves the light collection at the two ends of the scintillators. We have demonstrated that we can achieve timing resolution of  ( 1 ns) allowing good spatial resolution. Liquid scintillators with fibres read by Photo-multipliers or SiPMs provide an inexpensive alternative technology which suits well the requirement of the MATHUSLA experiment tracking system.

This Conceptual Design Report describes LUXE (Laser Und XFEL Experiment), an experimental campaign that aims to combine the high-quality and high-energy electron beam of the European XFEL with a powerful laser to explore the uncharted terrain of quantum electrodynamics characterised by both high energy and high intensity. We will reach this hitherto inaccessible regime of quantum physics by analysing high-energy electron-photon and photon-photon interactions in the extreme environment provided by an intense laser focus. The physics background and its relevance are presented in the science case which in turn leads to, and justifies, the ensuing plan for all aspects of the experiment: Our choice of experimental parameters allows (i) effective field strengths to be probed at and beyond the Schwinger limit and (ii) a precision to be achieved that permits a detailed comparison of the measured data with calculations. In addition, the high photon flux predicted will enable a sensitive search for new physics beyond the Standard Model. The initial phase of the experiment will employ an existing 40 TW laser, whereas the second phase will utilise an upgraded laser power of 350 TW. All expectations regarding the performance of the experimental set-up as well as the expected physics results are based on detailed numerical simulations throughout.

The LUXE experiment (Laser Und XFEL Experiment) is a new experiment in planning at DESY Hamburg using the electron beam of the European XFEL (Eu.XFEL). LUXE is intended to study collisions between a high-intensity optical laser and up to 16.5 GeV electrons from the Eu.XFEL electron beam, or, alternatively, high-energy secondary photons. The physics objective of LUXE are processes of Quantum Electrodynamics (QED) at the strong-field frontier, where QED is non-perturbative. The design of the experimental setup and the different detectors are presented.

The instantaneous luminosity of the Large Hadron Collider at CERN will be increased up to a factor of five with respect to the present design value by undergoing an extensive upgrade program over the coming decade. The most important upgrade project for the ATLAS Muon System is the replacement of the present first station in the forward regions with the so-called New Small Wheels (NSWs). The NSWs will be installed during the LHC long shutdown in 2018/19. Small-Strip Thin Gap Chamber (sTGC) detectors are designed to provide fast trigger and high precision muon tracking under the high luminosity LHC conditions. To validate the design, a full-size prototype sTGC detector of approximately 1.2 \\(\\times\\) \\(1.0\\, \\mathrm{m}^2\\) consisting of four gaps has been constructed. Each gap provides pad, strip and wire readouts. The sTGC intrinsic spatial resolution has been measured in a \\(32\\, \\mathrm{GeV}\\) pion beam test at Fermilab. At perpendicular incidence angle, single gap position resolutions of about \\(50\\,\\mathrm{\\mu m}\\) have been obtained, uniform along the sTGC strip and perpendicular wire directions, well within design requirements. Pad readout measurements have been performed in a \\(130\\, \\mathrm{GeV}\\) muon beam test at CERN. The transition region between readout pads has been found to be \\(4\\,\\mathrm{mm}\\), and the pads have been found to be fully efficient.

The plasma panel sensor (PPS) is a gaseous micropattern radiation detector under current development. It has many operational and fabrication principles common to plasma display panels. It comprises a dense matrix of small, gas plasma discharge cells within a hermetically sealed panel. As in plasma display panels, it uses nonreactive, intrinsically radiation-hard materials such as glass substrates, refractory metal electrodes, and mostly inert gas mixtures. We are developing these devices primarily as thin, low-mass detectors with gas gaps from a few hundred microns to a few millimeters. The PPS is a high gain, inherently digital device with the potential for fast response times, fine position resolution (<50-mm RMS) and low cost. In this paper, we report on prototype PPS experimental results in detecting betas, protons, and cosmic muons, and we extrapolate on the PPS potential for applications including the detection of alphas, heavy ions at low-to-medium energy, thermal neutrons, and X-rays.

The plasma panel sensor (PPS) is an inherently digital, high gain, novel variant of micropattern gas detectors inspired by many operational and fabrication principles common to plasma display panels (PDPs). The PPS is comprised of a dense array of small, plasma discharge, gas cells within a hermetically-sealed glass panel, and is assembled from non-reactive, intrinsically radiation-hard materials such as glass substrates, metal electrodes and mostly inert gas mixtures. We are developing the technology to fabricate these devices with very low mass and small thickness, using gas gaps of at least a few hundred micrometers. Our tests with these devices demonstrate a spatial resolution of about 1 mm. We intend to make PPS devices with much smaller cells and the potential for much finer position resolutions. Our PPS tests also show response times of several nanoseconds. We report here our results in detecting betas, cosmic-ray muons, and our first proton beam tests.