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As noble liquid time projection chambers grow in size their high voltage requirements increase, and detailed, reproducible studies of dielectric breakdown and the onset of electroluminescence are needed to inform their design. The Xenon Breakdown Apparatus (XeBrA) is a 5-liter cryogenic chamber built to characterize the DC high voltage breakdown behavior of liquid xenon and liquid argon. Electrodes with areas up to 33 cm2 were tested while varying the cathode-anode separation from 1 to 6 mm with a voltage difference up to 75 kV. A power-law relationship between breakdown field and electrode area was observed. The breakdown behavior of liquid argon and liquid xenon within the same experimental apparatus was comparable.

We present a measurement of the extraction efficiency of quasi-free electrons from the liquid into the gas phase in a two-phase xenon time-projection chamber. The measurements span a range of electric fields from 2.4 to 7.1 kV/cm in the liquid xenon, corresponding to 4.5 to 13.1 kV/cm in the gaseous xenon. Extraction efficiency continues to increase at the highest extraction fields, implying that additional charge signal may be attained in two-phase xenon detectors through careful high-voltage engineering of the gate-anode region.

We calibrate a two-phase xenon detector at 0.27 keV in the charge channel and at 2.8 keV in both the light and charge channels using a 37Ar source that is directly released into the detector. We map the light and charge yields as a function of electric drift field. For the 2.8 keV peak, we calculate the Thomas-Imel box parameter for recombination and determine its dependence on drift field. For the same peak, we achieve an energy resolution, Eσ/Emean, between 9.8% and 10.8% for 0.1 kV/cm to 2 kV/cm electric drift fields.

Liquid Argon (LAr) is one of the most widely used scintillators in particle detection, due to its low cost, high availability and excellent scintillation properties. A large number of experiments in the neutrino sector are based around using LAr in one or more Time Projection Chambers (TPCs), leading to high resolution three-dimensional particle reconstruction. In this paper, we review and summarise a number of these Liquid Argon Time Projection Chamber (LArTPC) experiments, and briefly describe the specific technologies that they currently employ. This includes single phase LAr experiments (ICARUS T600, MicroBooNE, SBND, LArIAT, DUNE-SP, ProtoDUNE-SP, ArgonCube and Vertical Drift) and dual phase LAr experiments (DUNE-DP, WA105, ProtoDUNE-DP and ARIADNE). We also discuss some new avenues of research in the field of LArTPC readout, which show potential for wide-scale use in the near future. [ABSTRACT FROM AUTHOR]

Liquid Argon (LAr) is one of the most widely used scintillators in particle detection, due to its low cost, high availability and excellent scintillation properties. A large number of experiments in the neutrino sector are based around using LAr in one or more Time Projection Chambers (TPCs), leading to high resolution three-dimensional particle reconstruction. In this paper, we review and summarise a number of these Liquid Argon Time Projection Chamber (LArTPC) experiments, and briefly describe the specific technologies that they currently employ. This includes single phase LAr experiments (ICARUS T600, MicroBooNE, SBND, LArIAT, DUNE-SP, ProtoDUNE-SP, ArgonCube and Vertical Drift) and dual phase LAr experiments (DUNE-DP, WA105, ProtoDUNE-DP and ARIADNE). We also discuss some new avenues of research in the field of LArTPC readout, which show potential for wide-scale use in the near future.

We tested the performance of two types of silicon photomultipliers, AdvanSiD ASD-NUV-SiPM3S-P and Hamamatsu 3×3 MM-50 UM VUV2, both at room (300 K) and at liquid nitrogen (77 K) temperature: breakdown voltage, quenching resistance, signal shape, gain and dark counts rate have been studied as function of temperature. The response of the devices to ultra-violet light is also studied. [ABSTRACT FROM AUTHOR]

An evaluation of the behavior of three large cathode area photo-multiplier tubes, Hamamatsu R5912 Mod and R5912-02 Mod, and ETL 9357 KFLB, was carried out both at room and cryogenic temperature, using a 405 nm light source. The main electrical and optical features of the devices were studied; the obtained results were compared with the characteristics of the ETL 9357 FLA tubes, used in the ICARUS experiment. Tubes were also studied as a function of the Earth׳s magnetic field and an evaluation of the quantum efficiency was made in the vacuum ultraviolet light region. [ABSTRACT FROM AUTHOR]

Abstract: ICARUS (Imaging Cosmic And Rare Underground Signals) is the the largest Liquid Argon Time Projection Chamber (LAr-TPC) in the world (containing _600 tons of LAr) addressed to the study of rare events and, among these, neutrino interactions. Installed in the Gran Sasso National Laboratory (INFN-LNGS, Italy), ICARUS started working gradually since May, 27th 2010, collecting data both from the cosmic rays able to reach the depths of the laboratory and from neutrino interactions from the CNGS beam. The detector, providing a completely uniform imaging and calorimetry with a high accuracy on massive volumes, allows to reconstruct in real time neutrino and cosmic interactions, measuring the full kinematics of the identified particles. The ICARUS technology can be considered as a milestone towards the realization of next generation of massive detectors (tens of ktons) for neutrino and rare event phy sics.In this paper a short description of the ICARUS T600 experiment, detector main features and performances and its first underground results are presented. [Copyright &y& Elsevier]

Abstract: A high Light Yield Liquid Argon chamber has been radiated with an Am/Be source for signal-to-background separation level characterization in a Dark Matter Liquid Argon based detector. Apart from the standard nuclear recoil and electron events, from neutron elastic interactions and gamma conversions respectively, an intermediate population has been observed which is attributed to inelastic neutron scatters on Argon nuclei producing Argon recoil and simultaneous gammas from nuclear de-excitation. Taking account of these events results in a better determination of the recoil-like to electron-like separation based on the shape of the scintillation pulse. The results of this recent study as well as from a previous study with a chamber with a lower Light Yield are presented. [Copyright &y& Elsevier]

The direct detection of the Universe's Dark Matter is one of the key questions in particle astrophysics. Cryogenic based detectors offer advantages in low radioactive backgrounds, target mass, sensitivity to the small energy depositions and rejection of possible background sources. I will summarize the main experimental approaches, including both cryogenic crystal and liquid targets and the options pursued for their signal readout. Recent advances from around the world and prospects for future proposed experiments will be discussed. [ABSTRACT FROM AUTHOR]

It is now well established and accepted that roughly 25% of the total mass-energy density of the Universe is in the form of non-relativistic particles. That these particles, referred to as Dark Matter, have remained a mystery has served as motivation for the design and implementation of increasingly ingenious and far reaching experiments in an attempt to identify and understand them. This paper will review various ongoing Dark Matter searches with focus on the variety of techniques and implementation used to both detect the rare Dark Matter interactions as well as reject the vast number of background events. [ABSTRACT FROM AUTHOR]