相关论文: New precise spectroscopy of the hyperfine structur…
Precise determinations of the masses of the $W$ boson and of the top quark could stringently test the radiative structure of the Standard Model (SM) or provide evidence for new physics. We analyze the excellent prospects at a muon collider…
We make precise calculation of hyperfine structure of $S$-states in muonic ions of lithium, beryllium and boron in quantum electrodynamics. Corrections of orders $\alpha^5$ and $\alpha^6$ due to the vacuum polarization, nuclear structure…
True muonium ($\mu^+\mu^-$) is one of the heaviest and smallest electromagnetic bound states not containing hadrons, and has never been observed so far. In this work it is shown that the spin-1 TM state (ortho-TM) can be observed at a…
We propose a new experiment to measure the running of the fine-structure constant in the space-like region by scattering high-energy muons on atomic electrons of a low-Z target through the process $\mu e \to \mu e$. The differential cross…
The spectrum of electrons from muons decaying in an atomic bound state is significantly modified by their interaction with the nucleus. Somewhat unexpectedly, its first measurement, at the Canadian laboratory TRIUMF, differed from basic…
In this work we describe the latest results for the measurements of the hyperfine structure of antiprotonic helium-3. Two out of four measurable super-super-hyperfine SSHF transition lines of the (n,L)=(36,34) state of antiprotonic helium-3…
A paramagnetic muonium (Mu) state with an extremely small hyperfine parameter was observed for the first time in single-crystalline GaN below 25 K. It has a highly anisotropic hyperfine structure with axial symmetry along the [0001]…
Axion-like particles and similar new pseudoscalar as well as vector bosons coupled to nucleons and electrons are predicted to lead to spin-dependent forces in atoms and ions. We argue that hyperfine structure measurements in hydrogen- and…
This paper describes measurements of the hyperfine structure of two antiprotonic atoms that are planned at the Antiproton Decelerator (AD) at CERN. The first part deals with antiprotonic helium, a three-body system of alpha-particle,…
The hyperfine splitting of the ground and low-energy $3/2^+(7.8 \pm 0.5$ eV) levels in the $^{229}$Th nucleus in muonic atom ($\mu^-_{1S_{1/2}}{}^{229}$Th$)^*$ has been calculated considering the distribution of the nuclear magnetization in…
The potential of muon colliders to study a low-energy supersymmetry is addressed in the framework of the minimal supergravity model, whose predictions are first briefly surveyed. Foremost among the unique features of a muon collider is…
Corrections of orders alpha^5, alpha^6 are calculated in the hyperfine splitting of the 2S state in the muonic hydrogen. The nuclear structure effects are taken into account in the one- and two-loop Feynman amplitudes by means of the proton…
The discovery of the proton-radius puzzle and the subsequent deuteron-radius puzzle is fueling an on-going debate on possible explanations for the difference in the observed radii obtained from muonic atoms and from electron-nucleus…
We develop an intuitive model of 2D microwave near-fields in the unusual regime of centimeter waves localized to tens of microns. Close to an intensity minimum, a simple effective description emerges with five parameters which characterize…
A muon collider is expected to produce a high intensity neutrino beam which is an admixture of either $\nu_{\mu}+\bar{\nu_e}$ or $\bar{\nu}_{\mu} +\nu_e$ which can can be directed to underground detectors far away from the source. It will…
Laser spectroscopy of muonic atoms has been recently used to probe properties of light nuclei with unprecedented precision. We introduce nuclear effects in hydrogen-like atoms, nucleon structure quantities (form factors, structure…
We report on measurements of the hyperfine $A, B$ and $C$-constants of the $3d4s^2 ~^2D_{5/2}$ and $3d4s^2 ~^2D_{3/2}$ atomic states in $^{45}$Sc. High-precision atomic calculations of the hyperfine fields of these states and second-order…
We perform precision microwave spectroscopy--aided by Stark deceleration--to reveal the low magnetic field behavior of OH in its ^2\Pi_{3/2} ro-vibronic ground state, identifying two field-insensitive hyperfine transitions suitable as…
We have measured the frequency splitting between the $(2S, F=1/2)$ and $(2S, F=3/2)$ hyperfine sublevels in atomic deuterium by an optical differential method based on two-photon Doppler-free spectroscopy on a cold atomic beam. The result…
We demonstrate efficient transverse compression of a 12.5 MeV/c muon beam stopped in a helium gas target featuring a vertical density gradient and crossed electric and magnetic fields. The muon stop distribution extending vertically over 14…