Search for H → WW → $$\ell \nu \ell \nu $$ Decays of a Heavy Higgs Boson Produced in pp Collisions at $$\sqrt s $$ = 13 TeV Using a 139-fb–1 Event Sample Recorded by the ATLAS Experiment

Physics of Atomic Nuclei - Events with final-state electron and muon pairs produced in pp collisions at $$\sqrt s $$ = 13 TeV are analyzed toward detecting H → WW → $$\ell \nu \ell \nu...     

On the Energy Dependence of the Rate of Muon Transfer from Proton to Oxygen

Physics of Atomic Nuclei - The results obtained by calculating the rate of muon transfer from the $$1s$$ state of muonic protium to a free-oxygen nucleus in the collision-energy range between...     

Birefringence induced by pp-wave modes in an electromagnetically active dynamic aether

The European Physical Journal C - We calculate the corrections for constant radial magnetic field in muon $${g}-2$$ and electric-dipole-moment experiments in storage rings. While the correction is...     

Measurement of the Michel Parameter $${\xi^{\prime}}$$ in Tau-Lepton Decays at the Super Charm-Tau Factory

Physics of Atomic Nuclei - In this paper, we present a feasibility study of the first measurement of the longitudinal polarization of a muon from the $$\tau$$ -lepton decay to extract the Michel...     

How much do charm sea quarks affect the charmonium spectrum?

The European Physical Journal C - We will examine the muon $$g-2$$ anomaly with the background of the Higgs global fit data in the framework of the Left-Right Twin Higgs (LRTH) Models. The joint...     

Measurement of Seasonal Variations of Horizontal Muons with Underground LVD Setup

The Large-Volume scintillation Detector commonly known as LVD and located at the Gran Sasso Laboratory at an average depth of 3650 m w.e. measures muons of intensity $$3.31\times 10^{-4}$$ m$${}^{-2}$$ s$${}^{-1}$$. The results obtained from an analysis of the properties of seasonal variations of the horizontal and vertical muon fluxes are presented in this article. Horizontal muons detected in LVD mostly correspond to rock depths of about 5 km w.e. and zenith angles $$\theta$$ of about $$75^{\circ}$$, while vertical muons ($$\theta\approx 13^{\circ}$$) correspond to depths of about 4.6 km w.e.     

The neutrinos in muon decay

We review the available information on the identity of the neutrino states emitted in muon decay, and discuss the exotic decay .     

Total cross sections of charged-current neutrino and antineutrino interactions on isoscalar nuclei

New measurements of the total crosssections of charged-current interactions of muonneutrinos and antineutrinos on isoscalar nuclei have been performed. Data were recorded in an exposure of the CHARM detector in an 160 GeV narrow-band beam. The antineutrino flux was determined from the measurements of the pion and kaon flux, and independently from the muon flux measured in the shield; the two methods are found to agree. The neutrino flux was determined from the muon flux ratio forv _μ and \(\bar v_\mu \) runs which was normalized to the antineutrino flux. The cross-section slopes thus determined are $$\begin{gathered} \sigma _T^{\bar v} /E = (0.335 \pm 0.004(stat) \hfill \\ \pm 0.010(syst)).10^{ - 38} cm^2 /(GeV \cdot nucleon) \hfill \\ \sigma _T^v /E = (0.686 \pm 0.002(stat) \hfill \\ \pm 0.020(syst)).10^{ - 38} cm^2 /(GeV \cdot nucleon) \hfill \\ \end{gathered} $$ The momentum sum of the quarks in the nucleon and the ratio of sea quark to total quark momentum are derived from the measurements.     

Single and multiple muons and the generation of neutrons in the LVD experiment

The large geometric factor and good spatial resolution of the Large Volume Detector (LVD) ensures statistically significant and highly accurate measurements of muon trajectories and determination of the multiplicity of muon groups. The developed algorithm allows us to reconstruct 2 × 10⁶ muon events (single muons and muon groups). Characteristics of muon groups are obtained and the specific yield of neutrons produced by single muons, muon groups, and showers is determined.     

Study on the Muon Backgroud in the Underground Laboratory of KIMS

KIMS is a group aiming at the search for WIMP. In WIMP search experiment, the muon is one important background. We measure the muon flux in Yangyang laboratory where is located at 700m underground. The structure and performance test of muon detector is described. The analysis on muon hit position and angle distribution has been performed. The simulations of muon flux have been done. The muon flux in the laboratory is found to be about (7.0±0.4)×10^-8/s/cm²/sr.     

The Muon Science Facility at the JKJ Project

The muon science facility is one of the experimental arenas of the JKJ project, which was recently approved for construction in a period from 2001 to 2006, as well as neutron science, particle and nuclear physics, neutrino physics and nuclear transmutation science. The muon science experimental area is planned to be located in the integrated building of the facility for the materials and life science study. One muon target will be installed upstream of the neutron target in a period of phase 1. The beam line and facility are designed to allow the later installation of a 2nd muon target in a more upstream location. The detailed design for electricity, cooling water, primary proton beam line, one muon target and secondary beam lines (a superconducting solenoid decay muon channel, a dedicated surface muon channel, and an ultra slow muon channel) is underway. In the symposium, a latest status of the muon science facility at JKJ project will be reported. This revised version was published online in August 2006 with corrections to the Cover Date.     

Cosmic Ray Muon on the Altitude of 5500m Above the Sea Level

215 blocks of K6,K7,K8 lead emulsion chambers on Mt.Kanbala are carefully scanned,and a total of 111 muon events are found with zenith angle M(=tgθ)>2.5.The energy of muon showers are determined by saddle-shape curves.The intensity of muon,the energy spectrum and the zenith angle distribution of muon showers on the altitude of 5500m above sea level are shown in the energy region E_μ>2TeV.Meanwhile the simulation calculation is done for the behaviour of muon inside the emulsion chamber,simulation results are basically in agreement with the experiment.     

Detection of GLE of December 13, 2006, using the muon hodoscope

GLE of December 13, 2006, is analyzed based on the data of the muon hodoscope located at MEPhI (Moscow). The setup supermodules registered that the muon flux intensity started increasing at 0254 UTC. An increase at a maximum (0300 UTC) was 0.61 ± 0.09% (for the 10-min data), which is larger than six standard deviations. The detection of the muon flux in the hodoscope mode for the first time made it possible to obtain the two-dimensional images of an increase in the muon flux. A comparison of the muon hodoscope and neutron monitor data makes it possible to conclude that the muon event was caused by a highly collimated bunch of the solar proton fast component.     

Effect of zero point motion on the hyperfine field at an interstitial positive muon site in ferromagnetic Ni

Using the inhomogeneous electron charge and spin density distribution around the octahedral site in ferromagnetic nickel from a self-consistent band structure scheme, and the abiabatic approximation, we have calculated the muon hyperfine field as a function of the muon displacement. By folding the electron spin density at the vibrating muon site obtained in a self-consistent Kohn-Sham scheme with the finite width of the muon wave function, we find a striking effect on the average muon hyperfine field. The result agrees better with the experiment than earlier calculations based on the jellium model.     

Aspects of the two-component and four-component neutrino theories in connection with weak lepton and semilepton processes

A comparison is made of the results found in the application of two-component and four-component theories of the two neutrinos to weak lepton processes (muon decay) and semilepton processes. The predictions of the two theories clearly differ in the V-A version of the coupling of electron and muon currents and of muon and baryon currents. In contrast with the theory of two-component neutrinos (the V-A interaction), four-component theory predicts that a V + A interaction of electron and muon currents is responsible for muon decay.     

Specific features of studying Forbush decreases in the muon flux

The variations in the cosmic ray (CR) muon flux during the Forbush decreases (FDs), registered by the DECOR muon detector and the URAGAN muon hodoscope during the periods of their operation from 2004 to 2006, are analyzed. The unified method for determining the parameters of variations in the CR flux during FDs has been developed, and the dependences of the FD characteristics on the rigidity of primary CRs and information about the spatial-angular dynamics of the muon flux during FDs have been obtained.     

Signals in the underground scintillation detectors of the Yakutsk array from muons of extensive air showers

A model of the underground part of the Yakutsk array was developed. The signals from muon scintillation detectors were calculated using the GEANT4 code within this model. It was shown that the signals strongly fluctuate and may be several times higher that the mean ionization energy losses by a single muon. These large losses imitate high muon multiplicity in the case of a low muon density. It was also shown that there are many gamma particles near the shower axis, which significantly contribute to signals in underground detectors and thus make data interpretation difficult.     

Muon diagnostics of the Earth’s atmosphere and magnetosphere

A method of distant monitoring of the Earth’s magnetosphere and atmosphere is described, which is based on the close correlation between the modulations in the flux of atmospheric muons detected at the Earth’s surface and the dynamic processes in the Earth’s magnetosphere and atmosphere and implies the use of large-area muon hodoscopes with high angular accuracy of muon detection. The results of the analysis of the experimental data obtained on the muon hodoscopes used at the Moscow Engineering Physics Institute show that muon detection at the Earth’s surface in the hodoscopic mode gives a qualitatively new information about the main sources of muon flux modulation.     

Alignment and measurement of the magnetic field for the BESIII muon counter

Based on cosmic ray events without a magnetic field taken with the BESIII detector during the summer shutdown of BEPCII in 2012 and di-muon events from a data sample taken at center-of-mass energy of 3.686 GeV in 2009, we compare the coordinates of hits registered in the BESIII muon counter with the expected interaction point extrapolated from reconstructed tracks from the inner tracking system in the absence of a magnetic field. By minimizing the difference, we align the muon counter with the inner tracking system. Moreover, the strength of the magnetic field in the muon counter is measured for the first time with di-muon events from data taken at a center-of-mass energy of 3.686 GeV. After the alignment and the magnetic field strength measurement, the offsets in the reconstructed hit positions for muon tracks are reduced, which improves the muon identification. The alignment and magnetic field strength measurement have been adopted in the latest version of the BESIII offline software system. This addition to the software reduces the systematic uncertainty for the physics analysis in cases where the muon counter information is used.     

Analysis of the anisotropy of the muon flux, according to data obtained by the URAGAN muon hodoscope during heliospheric disturbances

Features of studying heliospheric disturbances caused by changes in the parameters of the interplanetary magnetic field by the anisotropy of the muon flux of cosmic rays detected on the surface of the Earth by the URAGAN muon hodoscope are considered. The anisotropy of the muon flux in the period 2007–2011 is analyzed. The forecasting potential of our approaches to studying heliospheric disturbances using the penetrating component of cosmic rays is evaluated.