K. Mavrokoridis
A5104438592- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- Muon and positron interactions and applications
- Particle accelerators and beam dynamics
- Nuclear Physics and Applications
- Atmospheric Ozone and Climate
- Radiation Therapy and Dosimetry
- CCD and CMOS Imaging Sensors
- Spectroscopy and Laser Applications
- Cosmology and Gravitation Theories
- Calibration and Measurement Techniques
- Particle Accelerators and Free-Electron Lasers
- Gas Sensing Nanomaterials and Sensors
- Superconducting Materials and Applications
- Advanced NMR Techniques and Applications
- Electronic and Structural Properties of Oxides
- Parallel Computing and Optimization Techniques
- High-Energy Particle Collisions Research
- Astronomical Observations and Instrumentation
- Scientific Research and Discoveries
University of Liverpool
2015-2024
D. Mendeleyev University of Chemical Technology of Russia
2023
University of Pennsylvania
2021
Philadelphia University
2021
Colorado State University
2011
University of Sheffield
2006-2010
Imperial College London
2009
Rutherford Appleton Laboratory
2007-2009
University of Oxford
2009
Texas A&M University
2009
For the first time secondary scintillation, generated within holes of a thick gas electron multiplier (THGEM) immersed in liquid argon, has been observed and measured using silicon photomultiplier device (SiPM). 250 electron-ion pairs, argon via interaction 5.9 keV Fe-55 gamma source, were drifted under influence 2.5 kV/cm field towards 1.5 mm thickness THGEM, local sufficiently high to generate scintillation light as charge traversed central region THGEM hole. The resulting VUV was incident...
The T2K experiment studies oscillations of an off-axis muon neutrino beam between the J-PARC accelerator complex and Super-Kamiokande detector. Special emphasis is placed on measuring mixing angle theta_13 by observing electron appearance via sub-dominant to oscillation, searching for CP violation in lepton sector. includes a sophisticated, off-axis, near detector, ND280, situated 280 m downstream production target order measure properties understand better interactions at energy scale below...
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 experiments neutrino sector are based around using LAr or more Time Projection Chambers (TPCs), leading resolution three-dimensional reconstruction. In this paper, we review summarise a these Chamber (LArTPC) experiments, briefly describe specific technologies that they currently employ. This includes single phase...
To optimise the design of light readout in ArDM 1-ton liquid argon dark matter detector, a range reflector and WLS coating combinations were investigated several small setups, where scintillation was generated by radioactive sources gas at normal temperature pressure shifted into blue region tetraphenyl butadiene (TPB). Various thicknesses TPB deposited spraying vacuum evaporation onto specular 3M{\small\texttrademark}-foil diffuse Tetratex{\small\textregistered} (TTX) substrates. Light...
The ARIADNE project is developing innovative optical readout technologies for two-phase liquid Argon time projection chambers (LArTPCs). Optical presents an exciting alternative to the current paradigm of charge readout. simple, scalable and cost effective. This paper first demonstration 3D TPC, using CF4 gas as a proof principle. Both cosmic rays Americium-241 alpha source have been imaged in 100 mbar CF4. A single-photon sensitive camera was developed by combining Timepix3 (TPX3) based...
Abstract Argon gas doped with 1% wavelength-shifter (CF 4 ) has been employed in an optical time projection chamber (OTPC) to image cosmic radiation. We present results obtained during the system commissioning, performed two stacked glass thick gaseous electron multipliers (THGEMs) and electron-multiplying charge coupled device (EMCCD camera) at 1 bar. Preliminary estimates indicate that combined gain was of order 10 6 (ph/e), producing sharp high-contrast raw images without resorting any...
The performance of a silicon photomultiplier has been assessed at low temperature in order to evaluate its suitability as scintillation readout device liquid argon particle physics detectors. gain, measured 2.1 × 106 for constant over-voltage 4V was between 25°C and -196°C found be invariant with temperature, the corresponding single photoelectron dark count rate reducing from 1MHz 40Hz respectively. Following multiple thermal cycles no deterioration observed. photon detection efficiency...
The Argon Dark Matter (ArDM-1t) experiment is a ton-scale liquid argon (LAr) double-phase time projection chamber designed for direct searches. Such device allows to explore the low energy frontier in LAr with charge imaging detector. ionization extracted from into gas phase and there amplified by use of Large Electron Multiplier order reduce detection threshold. Direct fine spatial granularity, combined measurement amplitude evolution associated primary scintillation light, provide powerful...
Coulomb crystals have proven to be powerful and versatile tools for the study of ion–molecule reactions under cold controlled conditions. Reactions in are typically monitored through a combination situ fluorescence imaging laser-cooled ions destructive time-of-flight mass spectrometry measurements ejected ions. However, neither these techniques is able provide direct structural information on positions nonfluorescing "dark" within crystal. In this work, obtained using phosphor screen...
ArDM-1t is the prototype for a next generation WIMP detector measuring both scintillation light and ionization charge from nuclear recoils in 1-ton liquid argon target. The goal to reach minimum recoil energy of 30 keVr detect recoiling nuclei. In this paper we describe experimental concept present results on detection system, tested first time ArDM surface at CERN. With preliminary incomplete set PMTs, yield zero electric field found be between 0.3-0.5 phe/keVee depending position within...
This paper presents a preliminary study into the use of CCDs to image secondary scintillation light generated by THick Gas Electron Multipliers (THGEMs) in two phase LAr TPC. A Sony ICX285AL CCD chip was mounted above double THGEM gas 40 litre two-phase TPC with majority camera electronics positioned externally via feedthrough. An Am-241 source on rotatable motion feedthrough allowing positioning alpha either inside or outside field cage. Developed for and incorporated design novel high...
The ARIADNE Experiment, utilising a 1-ton dual-phase Liquid Argon Time Projection Chamber (LArTPC), aims to develop and mature optical readout technology for large scale LAr detectors. This paper describes the characterisation, using cosmic muons, of Timepix3-based camera mounted on detector. raw data from are natively 3D zero suppressed, allowing straightforward event reconstruction, gallery reconstructed interaction events is presented. Taking advantage 1.6 ns time resolution readout,...
Optical readout of large scale dual-phase liquid Argon TPCs is an attractive alternative to charge and has been successfully demonstrated on a 2 × m active region within the CERN protoDUNE cold box. ARIADNE+ uses four Timepix3 cameras imaging S2 light produced by 16 novel, patent pending, glass THGEMs. takes advantage raw data coming natively 3D zero suppressed with 1.6 ns timing resolution. Three THGEM quadrants implement readouts in visible range through wavelength shifting, fourth...
Future giant liquid argon (LAr) time projection chambers (TPCs) require a purity of better than 0.1 parts per billion (ppb) to allow the ionised electrons drift without significant capture by any electronegative impurities. We present comprehensive study effects impurity on gaseous and scintillation light, an analysis efficiency various purification chemicals, as well Liverpool LAr setup, which utilises novel re-circulation system. Of impurities tested - Air, O2, H2O, N2 CO2 in range between...
Colossal two-phase Liquid Argon Time Projection Chambers (LAr TPCs) are a proposed option for future long-baseline neutrino experiments. This study illustrates the feasibility of using an EMCCD camera to capture light induced by single cosmic events in LAr TPC employing THGEM. An Andor iXon Ultra 897 was externally mounted via borosilicate glass viewport on Liverpool TPC. The successfully captured secondary scintillation produced at THGEM holes that had been events. collection capability...
This paper details a novel, patent pending, abrasive machining manufacturing process for the formation of sub-millimetre holes in THGEMs, with intended application gaseous and dual-phase TPCs. Abrasive favours non-ductile substrate such as glasses or ceramics. innovative allows unprecedented versatility THGEM substrates, electrodes, hole geometry pattern. Consequently, THGEMs produced via can be tailored specific properties, example: high stiffness, low total thickness variation,...
ARIADNE is a 1-ton (330 kg fiducial mass) dual-phase liquid argon (LAr) time projection chamber (TPC) featuring novel optical readout. Four electron-multiplying charge-coupled device (EMCCD) cameras are mounted externally, and these capture the secondary scintillation light produced in holes of thick electron gas multiplier (THGEM). Track reconstruction using this readout approach demonstrated. Optical has potential to be cost effective alternative charge future LArTPCs. In paper, technical...
In liquid argon time projection chambers exposed to neutrino beams and running on or near surface levels, cosmic muons, other particles are incident the detectors while a single neutrino-induced event is being recorded. practice, this means that data from will be dominated by particles, both as source of triggers majority particle count in true neutrino-triggered events. work, we demonstrate novel application deep learning techniques remove these background applying full detector images SBND...