arXiv subjects

Yuanning Gao

Publications and source records attributed to Yuanning Gao.

At least 19 recordsLinked to original sources

arXiv2026

Simulation of the electron escape ratio for keV alpha-particle ionization tracks in liquid helium

The electron escape ratio for 5.3 MeV alpha-particle ionization tracks in liquid helium under varying external electric fields has been measured in several experiments. However, to the best of our knowledge, the corresponding ratio for keV-scale alpha tracks in the same medium has not yet been reported. In this article, we demonstrate for the first time that this ratio can be accurately characterized using COMSOL-based simulations. Our simulation framework was developed in two stages. In Stage I, we aimed to verify consistency between our simulated results and published experimental data for 5.3 MeV alpha particles. Following successful verification in Stage I, we proceeded to Stage II, in which the 5.3 MeV track was replaced by 2, 5, and 10 keV tracks. Our simulated results reveal that (a) keV-scale tracks exhibit electron escape ratios approximately 1.5-2.5 times higher than that of the 5.3 MeV track, and (b) the escape ratios for all track energies (2, 5, 10 keV, and 5.3 MeV) exhibit a linear dependence on the ion number density at the simulation's T0, but not on the electron number density.

astro-ph.IM↗

arXiv2026

Ferromagnetic broadband sensing of axionlike dark matter

Levitated particles have demonstrated ultrahigh sensitivity to magnetic fields and accelerations owing to their extremely low dissipation. Such systems have strong potential for fundamental physics research, particularly for the detection of axions and axionlike particles, well-motivated dark matter candidates spanning a broad mass range. In this context, both high sensitivity and large bandwidth are essential. Here, we demonstrate a levitated magnet magnetometer based on an engineered double-resonance mode, achieving an effective linewidth at its optimal sensitivity that is approximately three orders of magnitude broader than those of previous approaches. Together with a hard-magnet array that enhances the axion-induced signal and soft-ferromagnetic shielding that suppresses environmental magnetic noise, this system constitutes a hybrid ferromagnetic platform for axionlike dark matter searches. We search for axionlike dark matter through its photon coupling $g_{aγ}$ over the $40$-$3000\,\mathrm{Hz}$ frequency range and establish new direct limits in this frequency band. The best sensitivity is achieved near the upper resonance around $276\,\mathrm{Hz}$, where the magnetometer reaches a magnetic-field resolution of $0.7\,\mathrm{fT}$, corresponding to a limit of $g_{aγ}\sim10^{-7}\,\mathrm{GeV}^{-1}$. At this frequency, this result improves upon previous direct limits by more than four orders of magnitude. The demonstrated high-bandwidth levitated sensor may also enable a broad range of applications, including biological sensing and precision measurements.

hep-ex↗

arXiv2026

Colloquium: Hadron Production in Open-charm Meson Pair at $e^+e^-$ Collider

The standard model of particle physics is a well-established theoretical framework, yet several unresolved issues remain that warrant further experimental and theoretical exploration. In the realm of quark physics, these issues include understanding the nature of quark confinement and elucidating the mechanism linking quarks and gluons to strongly interacting particles within the standard model theory, which may offer insights into the underlying physics mechanisms. These issues inquiries can be addressed through the study of hadrons produced at $e^+e^-$ collisions and decaying to open-charm meson pairs utilizing the capabilities of {\it BABAR}, Belle, BESIII, and CLEO-c experiments, which have yielded valuable insights into nonstandard hadrons in recent decades. This Colloquium examines the contributions of $e^+e^-$ colliders from the {\it BABAR}, Belle, BESIII, and CLEO-c experiments to such studies in the past two decades and discusses future prospects for $e^+e^-$ collider experiments.

hep-ex↗

arXiv2026

Characterization of FBK NUV-HD-Cryo SiPMs near LHe temperature

Five FBK ``NUV-HD-Cryo'' SiPMs have been characterized at 7 K and 10 K, with 405 nm and 530 nm LED light, respectively. The dark count rate (DCR) was measured to be $\sim$ 1 Hz for the $\sim$ 100 mm$^2$-size SiPMs, or 0.01 Hz/mm$^2$, which is $\sim$ 7 orders lower than the DCR at room temperature (RT). Given the very low DCR at these cryogenic temperatures, we measured the SiPMs' I-V curves with such a method: illuminated the SiPMs with weak light, which differs from the conventional measurements at RT. Then, we measured the photo-detection efficiency (PDE), after-pulse (AP), and cross-talk (CT) with a bias voltage ranging from overvoltage (OV) 5 to 11 V. At the OV interval (5 to 11 V), the PDE was between 20\% - 45\%, and the AP and CT were both between $\sim$ 5\% and $\sim$ 20\%. With an OV higher than 10 V, the PDE would be $\ge$ 40\%, and the AP and CT are $\sim$ 20\%. Combining all of the measurements, we are confident that the SiPMs can be equipped as the photosensors on liquid helium detectors, including but not limited to the time projection chambers, which we have proposed in hunting for low-mass dark matter directly and beyond.

physics.ins-det↗

arXiv2025

New Physics Search at the CEPC: a General Perspective

The Circular Electron-Positron Collider (CEPC), a proposed next-generation Higgs factory, provides new opportunities to explore physics beyond the Standard Model (SM). With its clean electron-positron collision environment and the ability to collect large samples of Higgs, W, and Z bosons, the CEPC enables precision measurements and searches for new physics. This white paper outlines the CEPC's discovery potential, including studies of exotic decays of the Higgs, Z, and top quarks, dark matter and dark sector phenomena, long-lived particles, supersymmetry, and neutrino-related signatures. Advanced detector technologies and reconstruction techniques, such as one-to-one correspondence reconstruction and jet origin identification, significantly improve sensitivity to rare and weakly interacting processes. The CEPC is particularly well suited to probe the electroweak phase transition and test models of electroweak baryogenesis and dark sector interactions. In addition, global fit analyses highlight the CEPC's complementary role in constraining a wide range of new physics scenarios. These features position the CEPC as a powerful tool for exploring the next frontier in fundamental particle physics in the post-Higgs discovery era.

hep-ex↗

arXiv2025

Flavor Physics at the CEPC: a General Perspective

We discuss the landscape of flavor physics at the Circular Electron-Positron Collider (CEPC), based on the nominal luminosity outlined in its Technical Design Report. The CEPC is designed to operate in multiple modes to address a variety of tasks. At the $Z$ pole, the expected production of 4 Tera $Z$ bosons will provide unique and highly precise measurements of $Z$ boson couplings, while the substantial number of boosted heavy-flavored quarks and leptons produced in clean $Z$ decays will facilitate investigations into their flavor physics with unprecedented precision. We investigate the prospects of measuring various physics benchmarks and discuss their implications for particle theories and phenomenological models. Our studies indicate that, with its highlighted advantages and anticipated excellent detector performance, the CEPC can explore beauty and $τ$ physics in ways that are superior to or complementary with the Belle II and Large-Hadron-Collider-beauty experiments, potentially enabling the detection of new physics at energy scales of 10 TeV and above. This potential also extends to the observation of yet-to-be-discovered rare and exotic processes, as well as testing fundamental principles such as lepton flavor universality, lepton and baryon number conservation, etc., making the CEPC a vibrant platform for flavor physics research. The $WW$ threshold scan, Higgs-factory operation and top-pair productions of the CEPC further enhance its merits in this regard, especially for measuring the Cabibbo-Kobayashi-Maskawa matrix elements, and Flavor-Changing-Neutral-Current physics of Higgs boson and top quarks. We outline the requirements for detector performance and considerations for future development to achieve the anticipated scientific goals.

hep-ex↗

arXiv2024

A Monte Carlo Study of Single Baryon Reconstruction Method

A Monte Carlo study for single baryon reconstruction method is presented based on two-body baryonic decays of charmonium, $jJ/ψ$, $ψ(3686)\rightarrowΞ\barΞ$ at BESIII experiment. As a result, we find that the detection efficiency for single baryon reconstruction method can be increased by a factor of $\sim$4 relative to the traditional full-reconstruction method. It indicates that single baryon reconstruction method could be used in the other two-body baryonic decays of charmonium, such as $J/ψ$, $ψ(3686)\rightarrowΞ(1530)\barΞ(1530)$, $Ξ(1530)\barΞ$, whose expected yields are estimated based on single baryon reconstruction method. The expected uncertainties for the measurements of the angular distribution parameters are also discussed.

hep-ex↗

arXiv2024

A novel nuclear recoil calibration for liquid noble gas detectors

According to many dark matter models, a potential signal registered in a detector would feature a single-scattering nuclear recoil (NR). So, it is crucial to calibrate the detector's response to NR events. The conventional calibrations implement $\sim$ keV to MeV neutrons, which can be produced by an accelerator, a neutron generator, or a radioactive source. Although the calibrating methods have been widely employed, they could be improved in several ways: (a) the incident neutron energy should be more monoenergetic, (b) the calibrating NR energy should line up with the region of interest (ROI) of the experiment, and (c) the intensity of the beam should be appropriate. In the paper, we introduce a novel NR calibration method for liquid helium detectors, in which a helium beam ($α$ particles) will be implemented to calibrate the detectors. The helium beam can (i) be tuned precisely to have a jitter of $\lesssim $ 4\% (the $α$ beam's kinetic energy is equivalent to the recoil energy in the conventional calibrations with fast neutrons); (ii) have an energy between $\sim$ 100 eV and tens of keV; and (iii) provide a tunable flux from nA to 100 $μ$A, which presents convenience in beam pipe configuration to obtain a $\sim$ 100 Hz events rate so that the events pileup would be ignorable.

physics.ins-det↗

arXiv2023

A scheme to fix multiple solutions in amplitude analyses

Decays of unstable heavy particles usually involve the coherent sum of several amplitudes, like in a multiple slit experiment. Dedicated amplitude analysis techniques have been widely used to resolve these amplitudes for better understanding of the underlying dynamics. For special cases, where two spin-1/2 particles and two (pseudo-)scalar particles are present in the process, multiple equivalent solutions are found due to intrinsic symmetries in the summed probability density function. In this paper, the problem of multiple solutions is discussed and a scheme to overcome this problem is proposed by fixing some free parameters. Toys are generated to validate the strategy. A new approach to align helicities of initial- and final-state particles in different decay chains is also introduced.

hep-ph↗

arXiv2023

Search for ER and/or NR-like dark matter signals with the especially low background liquid helium TPCs

In the Dark Matter (DM) direct detection community, the absence of convincing signals has become a "new normal" for decades. Among other possibilities, the "new normal" might indicate that DM-matter interactions could generate not only the hypothetical NR (Nuclear Recoil) events but also the ER (Electron Recoil) ones, which have often been tagged as backgrounds historically. Further, we argue that ER and NR-like DM signals could co-exist in a DM detector's same dataset. So in total, there would be three scenarios we can search for DM signals: (i) ER excess only, (ii) NR excess only, and (iii) ER and NR excesses combined. To effectively identify any possible DM signal under the three scenarios, a DM detector should (a) have the minimum ER and NR backgrounds and (b) be capable of discriminating ER events from NR ones. Accordingly, we introduce the newly established project, ALETHEIA, which implements liquid helium-filled TPCs (Time Projection Chambers) in hunting for DM. Thanks to the nearly single-digit number of ER and NR backgrounds on 1 ton*yr exposure, presumably, the ALETHEIA detectors could identify any form of DM-induced excess in its ROI (Research Of Interest). As far as we know, ALETHEIA is the first DM direct detection experiment claiming such an inclusive search; conventional detectors search DM mainly on the "ER excess only" and/or the "NR excess only" channel, not the "ER and NR excesses combined" channel.

astro-ph.IM↗

arXiv2023

Conceptual design and progress of transmitting $\sim$ MV DC HV into 4 K LHe detectors

A dual-phase TPC (Time Projection Chamber) is more advanced in characterizing an event than a single-phase one because it can, in principle, reconstruct the 3D (X-Y-Z) image of the event, while a single-phase detector can only show a 2D (X-Y) picture. As a result, more enriched physics is expected for a dual-phase detector than a single-phase one. However, to build such a detector, DC HV (High Voltage) must be delivered into the chamber (to have a static electric field), which is a challenging task, especially for an LHe detector due to the extremely low temperature, $\sim$ 4 K, and the very high voltage, $\sim$ MV (Million Volts). This article introduces a convincing design for transmitting $\sim$ MV DC into a 4 K LHe detector. We also report the progress of manufacturing a 100 kV DC feedthrough capable of working at 4 K. Surprisingly, we realized that the technology we developed here might be a valuable reference to the scientists and engineers aiming to build residential bases on the Moon or Mars.

physics.ins-det↗

arXiv2022

ALETHEIA: Hunting for Low-mass Dark Matter with Liquid Helium TPCs

Dark Matter (DM) is one of the most critical questions to be understood and answered in fundamental physics today. Observations with varied astronomical and cosmological technologies strongly indicated that DM exists in the Universe, the Milky Way, and the Solar System. Nevertheless, understanding DM under the language of elementary physics is still in progress. DM direct detection tests the interactive cross-section between galactic DM particles and an underground detector's nucleons. Although Weakly Interactive Massive Particles (WIMPs) are the most discussed DM candidates, the null-WIMPs conclusion has been consistently addressed by the most convincing experiments in the field. Relatively, the low-mass WIMPs region ($\sim$ 10 MeV/c$^2$ - 10 GeV/c$^2$) has not been fully exploited compared to high-mass WIMPs ($\sim$ 10 GeV/c$^2$ - 10 TeV/c$^2$). The ALETHEIA (A Liquid hElium Time projection cHambEr In dArk matter) experiment aims to hunt for low-mass WIMPs with liquid helium-filled TPCs (Time Projection Chambers). In this paper, we go through the physics motivation of the project, the detector's design, the R\&D plan, and the progress we have made since the project has been launched in the summer of 2020.

astro-ph.IM↗

arXiv2022

Introduction to a low-mass dark matter project, ALETHEIA: A Liquid hElium Time projection cHambEr In dArk matter

Dark Matter (DM) is one of the most critical questions to be understood and answered in fundamental physics today. Plenty of astronomical and cosmological observations have already pinned down that DM exists in the Universe, the Milky Way, and the Solar System. However, understanding DM with the language of elementary physics is still in progress. DM direct detection tests the interactive cross-section between galactic DM particles and an underground detector's nucleons. WIMPs is the most discussed DM candidate. After decades of hunting, a convincing WIMPs signal is still at large. Relatively, the low-mass WIMPs region ($\sim$ 10 MeV/c$^2$ - 10 GeV/c$^2$) has not been fully exploited compared to high-mass WIMPs ($\sim$ 10 GeV/c$^2$ - 10 TeV/c$^2$). By filling the arguably cleanest bulk material, LHe, into the arguably most competitive detector in the field, TPCs, ALETHEIA is supposed to achieve an extremely low-level background; therefore, to help answer one of the most pressing physical questions today: the nature of DM. In this paper, we briefly go through the physics motivation of low-mass DM, the ALETHEIA detector's design, possible analysis channels available for DM searches, and the progress we have made since the project launched in the summer of 2020.

astro-ph.IM↗

arXiv2022

NETR-Tree: An Eifficient Framework for Social-Based Time-Aware Spatial Keyword Query

The development of global positioning system stimulates the popularity of location-based social network (LBSN) services. With a large volume of data containing locations, texts, check-in information, and social relationships, spatial keyword queries in LBSNs have become increasingly complex. In this paper, we identify and solve the Social-based Time-aware Spatial Keyword Query (STSKQ) that returns the top-k objects by considering geo-spatial score, keywords similarity, visiting time score, and social relationship effect. To tackle STSKQ, we propose a two-layer hybrid index structure called Network Embedding Time-aware R-tree (NETR-Tree). In the user layer, we exploit the network embedding strategy to measure the relationship effect in users' relationship network. In the location layer, we build a Time-aware R-tree (TR-tree) considered spatial objects' spatiotemporal check-in information, and present a corresponding query processing algorithm. Finally, extensive experiments on two different real-life LBSNs demonstrate the effectiveness and efficiency of our methods, compared with existing state-of-the-art methods.

cs.SI↗

arXiv2021

A low-mass dark matter project, ALETHEIA: A Liquid hElium Time projection cHambEr In dArk matter

Dark Matter (DM) is one of the most critical questions to be understood and answered in fundamental physics today. Observations with varied astronomical and cosmological technologies already pinned down that DM exists in the Universe, the Milky Way, and the Solar System. However, the understanding of DM under the language of elementary physics is still in progress. DM direct detection aims to test the interactive cross-section between galactic DM particles and an underground detector's nucleons. Although Weakly Interactive Massive Particles (WIMPs) is the most discussed DM candidate, the null-WIMPs conclusion has been consistently addressed by most convincing experiments in the field. The low-mass WIMPs region (100s MeV/c$^2$ - 10 GeV/c$^2$) has not been fully exploited comparing to high-mass WIMPs (10 GeV/c$^2$ - 1 TeV/c$^2$) experiments which implement liquid xenon or argon TPCs (Time Projection Chambers). The ALETHEIA experiment aims to hunt for low-mass WIMPs with liquid helium-filled TPCs. In this paper, we go through the physics motivation of low-mass DM, the ALETHEIA detector's design, a series of R&D programs that should be launched to address a liquid helium TPC's functionality, and possible analysis channels available for DM searches. We designed and homemade a 30 g liquid helium prototype detector at CIAE. In Summer 2021, the detector was cooled down to 4.5 K successfully. The detector's dark current is less than ten pA for an external voltage up to 17 kV/cm when filled with vacuum, 1 atm nitrogen gas, and liquid nitrogen.

astro-ph.IM↗

arXiv2021

ILC Study Questions for Snowmass 2021

To aid contributions to the Snowmass 2021 US Community Study on physics at the International Linear Collider and other proposed $e^+e^-$ colliders, we present a list of study questions that could be the basis of useful Snowmass projects. We accompany this with links to references and resources on $e^+e^-$ physics, and a description of a new software framework that we are preparing for $e^+e^-$ studies at Snowmass.

hep-ph↗

arXiv2019

Helicity Amplitude Analysis of $J/ψ$ and $ψ(2S)\rightarrowΞ(1530)\barΞ(1530)$

We perform a helicity amplitude analysis for the processes of $e^+e^-$$\rightarrow$$J/ψ,ψ(2S)\rightarrowΞ(1530)\barΞ(1530)\rightarrowππΞ\barΞ\rightarrowΛ\bar\Lambda4π\rightarrow p\bar{p}6π$. The joint angular distribution for these processes are obtained, which allows a proper estimation of the detection efficiency using helicity amplitude information. In addition, the sensitivities of measurement of hyperon asymmetry decay parameters for these processes are discussed.

hep-ex↗

arXiv2019

Precision Higgs Physics at CEPC

The discovery of the Higgs boson with its mass around 125 GeV by the ATLAS and CMS Collaborations marked the beginning of a new era in high energy physics. The Higgs boson will be the subject of extensive studies of the ongoing LHC program. At the same time, lepton collider based Higgs factories have been proposed as a possible next step beyond the LHC, with its main goal to precisely measure the properties of the Higgs boson and probe potential new physics associated with the Higgs boson. The Circular Electron Positron Collider~(CEPC) is one of such proposed Higgs factories. The CEPC is an $e^+e^-$ circular collider proposed by and to be hosted in China. Located in a tunnel of approximately 100~km in circumference, it will operate at a center-of-mass energy of 240~GeV as the Higgs factory. In this paper, we present the first estimates on the precision of the Higgs boson property measurements achievable at the CEPC and discuss implications of these measurements.

hep-ex↗