arXiv subjects

Jianyang Qi

Publications and source records attributed to Jianyang Qi.

5 recordsLinked to original sources

arXiv2026

Design of ALPHA Phase I: A Plasma Haloscope for 10--20 GHz Post-Inflation Axions

The axion is a well-motivated hypothetical particle capable of resolving both the strong CP problem and the dark matter mystery, with recent post-inflationary cosmological simulations favoring masses above 40 μeV. Plasma haloscopes serve as a promising experimental approach to reach theoretically preferred sensitivities in this mass range. ALPHA, hosted at Yale Wright Laboratory, is an international collaboration developing plasma haloscopes to search for QCD dark matter axions. In this letter we present the detailed design and sensitivity projection for the first phase of the ALPHA experiment, which will search the mass range from 10 GHz to 20 GHz (~40 μeV to 80 μeV). This search will make use of wire-array plasma resonators to decouple the physical size from the resonant frequency, a limitation typically faced by traditional microwave cavities, allowing broadband sensitivity approaching KSVZ coupling strengths.

hep-ex↗

arXiv2026

Gas Electroluminescence in a Dual Phase Xenon-Doped Argon Detector

Noble element detectors using argon or xenon as the detection medium are widely used in the searches for rare neutrino and dark matter interactions. Xenon doping in liquid argon can preserve attractive properties of an argon target while enhancing the detectable signals with properties of xenon. In this work, we deployed a dual-phase liquid argon detector with up to 4% xenon doping in the liquid and studied its gas electroluminescence properties as a function of xenon concentration. At $\sim$2% xenon doping in liquid argon, we measured $\sim$34 ppm of xenon in the gas and observed $\sim$2.5 times larger electroluminescence signals in the detector than those in pure argon. By analyzing signals recorded by photosensors of different wavelength sensitivities, we confirm that the argon gas electroluminescence process is strongly affected by the addition of xenon. We propose an analytical model to describe the underlying energy transfer mechanism in argon-xenon gas mixtures. Lastly, the implications of this measurement for low energy ionization signal detection will be discussed.

physics.ins-det↗

arXiv2024

Feasibility of Liquid-phase Xenon Proportional Scintillation for Low-energy Physics

Dual phase xenon time projection chambers (TPCs) detect both the scintillation photons and ionization electrons created by energy depositions within the liquid xenon (LXe) volume. The electrons are extracted from the interaction site through a gas gap, where they meet a high electric field where proportional scintillation occurs. This converts the electron signal into a light signal, and yields a high electron detection efficiency with a gain of tens of photoelectrons (PE) per electron. This technique of detecting both scintillation and ionization gives dual phase xenon TPCs the capability to distinguish between electronic and nuclear recoils, which is a key part of how these detectors are able to reach world-leading limits on Weakly Interacting Massive Particle (WIMP) dark matter. However, not all electrons can be extracted through the liquid-gas interface, and a constant millimeter-scale gas gap needs to be maintained, which may be a technological challenge if dual-phase xenon TPCs are to be scaled up for future dark matter searches. Furthermore, there is a background of single-electron peaks that follow a large ionization signal (S2) of unclear origin which may be due in part to the liquid-gas interface, and limits the sensitivity of these detectors towards low mass dark matter. In this paper, we demonstrate that a purely single-phase liquid xenon TPC which produces proportional scintillation directly in the liquid is still capable of discriminating between electronic and nuclear recoils, but that the background of single-electrons following an S2 is still likely unrelated to the liquid-gas interface.

physics.ins-det↗

arXiv2023

Low Energy Electronic Recoils and Single Electron Detection with a Liquid Xenon Proportional Scintillation Counter

Liquid xenon (LXe) is a well-studied detector medium to search for rare events in dark matter and neutrino physics. Two-phase xenon time projection chambers (TPCs) can detect electronic and nuclear recoils with energy down to kilo-electron volts (keV). In this paper, we characterize the response of a single-phase liquid xenon proportional scintillation counter (LXePSC), which produces electroluminescence directly in the liquid, to detect electronic recoils at low energies. Our design uses a thin (10 - 25 $μ$m diameter), central anode wire in a cylindrical LXe target where ionization electrons, created from radiation particles, drift radially towards the anode, and electroluminescence is produced. Both the primary scintillation (S1) and electroluminescence (S2) are detected by photomultiplier tubes (PMTs) surrounding the LXe target. Up to 17 photons are produced per electron, obtained with a 10 $μ$m diameter anode wire, allowing for the highly efficient detection of electronic recoils from beta decays of a tritium source down to roughly 1 keV. Single electrons, from photo-emission of the cathode wires, are observed at a gain of 1.8 photoelectrons (PE) per electron. The delayed signals following the S2 signals are dominated by single-photon-like hits, without evidence for electron signals observed in the two-phase xenon TPCs. We discuss the potential application of such a LXePSC for reactor neutrino detection via Coherent Elastic Neutrino Nucleus Scattering (CE$ν$NS).

physics.ins-det↗

arXiv2022

Performance of a Radial Time Projection Chamber with Electroluminescence in Liquid Xenon

The dual-phase xenon time projection chamber (TPC) is a leading detector technology in rare event searches for dark matter and neutrino physics. The success of this type of detector technology relies on its capability to detect both primary scintillation and ionization signals from particle interactions in liquid xenon (LXe). The ionization electrons are converted into electroluminescence in the gas xenon (GXe), where a single electron can be amplified by more than 100 times in number of photons in a strong electric field. Maintaining a strong and uniform electric field in the small gas gap in large diameter TPCs is challenging. One alternative solution is to produce the electroluminescence in the LXe directly to overcome the gas gap uniformity problem. Here we report on the design and performance of a single-phase Radial TPC (RTPC) which can create and detect the electroluminescence directly in LXe. It simplifies the design and operation of the LXe TPC by using a single wire in the axial center to create the strong electric field. We present the performance of such an RTPC and discuss its limitations for potential applications.

physics.ins-det↗