As a fundamental subatomic particle, muon has many unique properties that make it an important tool for research in Physics, Chemistry, and Materials science. In recent years, abundant achievements have been made in the generation and application of muon beam, such as μSR, muon tomography, muon cooling, and muon collider. However, because we did not have suitable proton accelerators before,...
At J-PARC, a muon linac is being developed for future muon $g-2$/EDM experiments. The muon linac starts with an ultra-slow muon (USM) source that generates muons with an extremely small momentum of 3 keV/c (kinetic energy W=25 meV) by laser ionization of thermal muonium. The generated USM accelerated to 5.6 keV by an electrostatic field and injected into a radio frequency quadrupole (RFQ). The...
The Fermilab Muon g-2 Experiment aims to search for evidence of new physics by measuring the anomalous magnetic moment of muons, represented by the quantity (g-2)/2. The experiment injects muons into a storage ring, where the precession frequency is measured to determine (g-2)/2.
The analysis of the experiment involves two main components: measuring the difference frequency (ωa) between the...
The COMET (COherent Muon to Electron Transition) experiment at the Japan Proton Accelerator Research Complex (J-PARC) is a cutting-edge high-energy physics experiment that aims to search for the muon-to-electron conversion process, which is a rare phenomenon that would be a clear indication of physics beyond the Standard Model. The COMET experiment utilizes a high-intensity proton beam from...
Lepton flavor is a conserved quantity of nature in the standard model. With the discovery of neutrino oscillation, charged lepton flavor violation (CLFV) is predicted to exist by various New Physics theories beyond the standard model. The Mu2e experiment at Fermilab will search for the CLFV process of neutrinoless muon to electron conversion in the field of a nucleus. Mu2e aims to measure the...
In the standard model (SM), neutrinos are massless and lepton flavor is conserved. However, the discovery of neutrino oscillations indicates that neutrinos are massive and there is lepton mixing. On the one hand, tiny neutrino masses result in extremely low weak-interaction-induced lepton flavor violation branching ratio, making it impossible to observe. On the other hand, if the tiny neutrino...
The Fermilab Muon g-2 experiment aims to measure the magnetic anomaly of the muon at the precision level of 140 ppb. The data model to extract the anomalous precession frequency is subjected to various beam dynamics corrections, contributing significantly to the systematics of the extracted frequency. These beam dynamics corrections were estimated by monte-carlo simulations, which often are...
Muon plays an essential role in both fundamental physics research and applied sciences. And the high quality of muon beam is the key to realizing research and application. A muon beam is typically produced in a proton accelerator complex through the proton-on-target process. Recently, other types of particles, such as high-energy electrons, gamma rays, and laser beams, have been proposed to...
The Run1 result of the Fermilab muon g-2 experiment have shown a 4.2 standard deviation between the experimental measurement and theoretical prediction of $a_{\mu}$, strongly indicating a new physics signal.
The experiment already accumulated 21x data compared to the BNL experiment. The J-PARC muon g-2 experiment will collect ~3.5x statistics compared to Fermilab. It can be expected that,...
Longitudinally polarized Vector Boson Scattering (VBS) process provides us with a perfect probe to precisely measure electroweak observables and Higgs coupling as massive vector bosons have longitudinally polarized components originating from the Higgs mechanism. A TeV-scaled muon collider that would effectively be a “high-luminosity weak boson collider”, has great potential to measure VBS...
Signs of charged lepton flavor violation (cLFV) processes directly indicate the existence of new physics beyond the standard model. The COMET experiment is located at the Japan High Current Proton Accelerator Center (J-PARC), and its goal is to find the charged lepton flavor violation process μN→eN with an accuracy of more than 10-17. In order to obtain high-precision experimental results, it...
Here I present our recent proposal for connecting neutrino and energy frontiers by exploiting collimated muon beams for neutrino oscillation. As know, neutrino oscillation is one the most important problems beyond standard model physics. Its observations enable us to infer that neutrinos have masses, although tiny. Another crucial problem within neutrino physics is the violation of Charge and...
The first phase of the muEDM experiment at Paul Scherrer Institute (PSI), Switzerland, aims to probe the muon electric dipole moment (EDM) using the frozen-spin technique in a compact storage ring, at a sensitivity of 3×10-21 e⋅cm. A fast entrance detector is expected to work in concert with a magnetic pulse generator to kick muons to the desired orbit. At the same time, the...
Dear organizing committee,
I will be representing our group to introduce our recent progress in the form of a poster presentation. Our work is focused on revealing the origin of neutrino masses through the Type II and Type III Seesaw mechanism at high-energy muon colliders.Here are the related papers we published on this work
[https://arxiv.org/abs/2301.07274][2] and...
Charmonium weak decay is allowed in the Standard Model but has never been observed. Using $(10087\pm44)\times{10}^6$ $J/\psi$ events collected with the BESIII detector at the BEPCII $e^+e^-$ storage ring at the center-of-mass energy of $\sqrt s=3.097\ \rm{GeV}$, we present a search for the charmonium rare semi-muonic decay $J/\psi\rightarrow D^-\mu^+\nu_\mu$ and its charge conjugation ($c.c.$)...
In this talk, I will introduce the muon spin rotation/relaxation (muSR) method in application to study superconducting materials. I will also present our experimental results obtained on several unconventional superconducting systems, including Sr2RuO4, Ba1-xKxFe2As2 and FeSe, under various experimental conditions (in zero and applied magnetic field, under hydrostatic and uniaxial pressure)...
Muon spin spectroscopy, known as a collection of muon spin rotation, relaxation and resonance (μSR) techniques, uses highly polarized muons to study the microscopic magnetic structure and dynamics of condensed matter. The interaction between muon spins and the local field inside materials forms the physical basis of μSR techniques. Such information is extracted by the detection of positrons...
宇宙射线缪子是由来自太空的高能宇宙射线与大气层相互作用产生的次级射线粒子，具有极强的穿透能力，不易受高Z屏蔽体的干扰，没有人工辐射，避免了从业人员辐照损伤的风险，这使得缪子成像技术在近十年得到了广泛的关注和应用。在过去的几十年间，有关宇宙射线缪子探测技术研究课题的数量在持续增长，成果应用范围也不断拓展。当前宇宙射线缪子成像技术主要可分为两大类：基于多次角度散射和基于强度衰减的两种机理的成像技术。缪子成像技术也被国际辐射探测成像和粒子探测领域公认为21世纪极具开发价值与应用前景的新型成像技术，本报告将重点讲述当前国内外有关缪子成像的研究，并介绍南华大学在该领域取得的一些成果。
缪子对撞机具有高对撞能量和干净本底的优势，对于寻找新物理过程有着特别的潜力。而当前粒子物理对于早期宇宙的诸多问题还尚未有确切的答案，比如宇宙正反物质不对称该如何解释，电弱相变的确切图案是怎样的？缪子对撞机的高对撞能量给予了检验早期宇宙这些问题的可能性，其干净的本底和较大的亮度有望让我们对上述问题的参数空间有着更进一步的检验。在这个报告中，我们将寻找缪子对撞机上的新物理过程与早期宇宙的关联，尤其是揭示宇宙正反物质不对称的轻子生成机制，和电弱相变图案。
Motivated by the recent rare B decays measurements, we study the matching procedure of operators O9,O10 in the low energy effective Hamiltonian and operators in the Standard Model effective theory (SMEFT). It is noticed that there are more related operators in the SMEFT whose coefficients can not be determined only from the low-energy data from B physics. We demonstrate how to determine these...
- We propose a neutrino lepton collider where the neutrino beam is generated from TeV scale muon decays. Such a device would allow for a precise measurement of the W mass based on single W production. Although it is challenging to achieve high instantaneous luminosity with such a collider, we find that a total luminosity of 0.1/fb can already yield competitive physics results
- We further...
Muon collider is a potential accelerator solution for future particle physics in energy frontier. It provides unique properties to the research in multi-TeV energy range, as compared to other accelerator solutions such as proton-proton colliders and linear electron-positron colliders. This talk reviews the worldwide study history of muon colliders since 1990’s, different design schemes, R&D...
