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تسجيل مستخدم جديدRecent Advances in Bubble-Assisted Liquid Hole Multipliers in Liquid Xenon
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We report on recent advances in the operation of bubble-assisted Liquid Hole Multipliers (LHM). By confining a vapor bubble under or adjacent to a perforated electrode immersed in liquid xenon, we could record both radiation-induced ionization electrons and primary scintillation photons in the noble liquid. Four types of LHM electrodes were investigated: a THGEM, standard double-conical GEM, 50 $mu$m-thick single-conical GEM (SC-GEM) and 125 $mu$m-thick SC-GEM - all coated with CsI photocathodes. The 125 $mu$m-thick SC-GEM provided the highest electroluminescence (EL) yields, up to ~400 photons per electron over 4$pi$ with an RMS pulse-height resolution reaching 5.5% for events comprising ~7000 primary electrons. Applying a high transfer field across the bubble, the EL yield was further increased by a factor of ~5. The feasibility of a vertical-mode LHM, with the bubble confined between two vertical electrodes, and the operation of a two-stage LHM configuration were demonstrated for the first time. We combine electrostatic simulations with observed signals to draw conclusions regarding the location of the liquid-gas interface and suggest an explanation for the observed differences in EL yield between the investigated electrodes.
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In bubble-assisted Liquid HoleMultipliers(LHM), developed for noble-liquid radiation detectors, the stability of the bubble and the electro-mechanical properties of the liquid-to-gas interface play a dominant role in the detector performance. A model
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Bubble formation in liquid xenon underneath a Thick Gaseous Electron Multiplier (THGEM) electrode immersed in liquid xenon was observed with a CCD camera. With voltage across the THGEM, the appearance of bubbles was correlated with that of electrolum
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First imaging results in liquid xenon of a Liquid Hole Multiplier (LHM) coupled to a Quad-Silicon Photomultiplier (SiPM) array are presented. Ionization electrons deposited in the noble liquid by 5.5 MeV alpha particles, are collected into the holes
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The bubble-assisted Liquid Hole Multiplier (LHM) is a novel concept for the combined detection of ionization electrons and scintillation photons in noble-liquid time projection chambers. It consists of a perforated electrode immersed in the noble liq
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