For the first time, the successful operation of the so-called "bubble- assisted Liquid Hole-Multiplier" (LHM) in liquid argon was demonstrated. The LHM represents a novel concept for the combined detection of radiation-induced ionization electrons and primary scintillation photons. This detector consists of a perforated electrode (THGEM) immersed in the noble liquid with an inflated stable gas bubble trapped underneath. Electrons created in the liquid or scintillation-induced photoelectrons emitted from a CsI photocathode deposited on the electrode’s surface are collected into the holes and transferred from the liquid phase into the gaseous one. In the bubble, electroluminescence is induced and detected with a PMT or a pixilated SiPM array – to provide the event’s energy and localization.
We will present the concept and show preliminary results of the LHM performance in liquid argon.
Potential applications will be briefly discussed.