Repolarization of Negative Muons by Polarized<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi mathvariant="normal">Bi</mml:mi></mml:mrow><mml:mprescripts /><mml:mrow /><mml:mrow><mml:mn>209</mml:mn></mml:mrow><mml:mrow /><mml:mrow /></mml:mmultiscripts></mml:mrow></mml:math>Nuclei

Kadono, R.; Imazato, J.; Ishikawa, Takashi; Nishiyama, K.; Nagamine, K.; Yamazaki, T.; Bosshard, A.; Döbeli, M.; Elmbt, Larry van; Schaad, M. W.; Truöl, P.; Bay, A.; Perroud, J. P.; Deutsch, J.; Tasiaux, Bernadette; Hagn, E.

doi:10.1103/physrevlett.57.1847

Cited by 16 publications

(2 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Because of its large spin, Bi is strongly polarized by the internal magnetic field of ferromagnetic compounds BiMn. 6) In these studies it is very important to have accurate information on the degree of muon polarization in the 1s1/2 state of muonic atoms experimentally.…”

Section: Introductionmentioning

confidence: 99%

Angular Distribution of Electrons in Bound Muon Decay

Watanabe¹,

Fukui²,

Ohtsubo³

et al. 1987

Progress of Theoretical Physics

View full text Add to dashboard Cite

A general formalism of the angular distribution of emitted electrons in the bound muon decay is made in terms of the multi pole series of the relativistic electron wave functions. The effect of the finite size nucleus to wave functions is properly taken into account for the bound muon and emitted electron. In order to show the importance of this effect, energy spectra and asymmetry coefficients are given numerically in the cases of 160, 40Ca, 90Zr and 2°"Pb. § 1. Introduction Recent development of experimental facilities has made it possible to produce high-intensity muon beams available for studying various fields of physics. In nuclear physics there have been increasing interests in polarization phenomena due to the muon capture in complex nuclei. These are asymmetric distribution of neutrons after the muon capture, I) nuclear polarization of the daughter nucleV) asymmetry of y-rays in radiative capture, etc. 3 ) In atomic physics there are also a number of publications. Two of them are referred to here on the depolarization of bound muons due to the spin-orbit interactions and hyperfine interactions between muon and nucleus,4),5) and the repolarization of bound muons due to hyperfine interactions of muon with Bi. Because of its large spin, Bi is strongly polarized by the internal magnetic field of ferromagnetic compounds BiMn.6) In these studies it is very important to have accurate information on the degree of muon polarization in the 1s1/2 state of muonic atoms experimentally.In the muon decay, the emitted electron is distributed asymmetrically with respect to the muon polarization axis because of parity nonconservation. Therefore, the muon polarization in the 1s1/2 state of a muonic atom is deterinined by measuring the asymmetric distribution of electrons in the bound muon decay. Since the measured electron asymmetry is described by a product of the muon polarization and the asymmetry parameter, it is indispensable to know a theoretical value of the asymmetry parameter in the bound muon decay in order to extract the muon polarization from the measured electron asymmetry accurately. The asymmetry parameter is supposed to be different from that in the free muon decay. Until now this difference is, however, not fully clarified yet.In the early 1950's, Porter and PrimakoW) first pointed out that the decay rate and the electron energy spectrum in the bound muon decay are quite different from those in the free muon decay. Later, there appeared several works on these problems. B )-Il)Huff 9 ) and Hanggi et al. lO ) calculated the electron energy spectrum in heavy muonic atoms accurately, where they expanded electron wave functions into partial waves and took the nuclear finite size effect into account.On the other hand there were only two publications on the electron angular

show abstract

Section: Introductionmentioning

confidence: 99%

Angular Distribution of Electrons in Bound Muon Decay

Watanabe¹,

Fukui²,

Ohtsubo³

et al. 1987

Progress of Theoretical Physics

View full text Add to dashboard Cite

show abstract

“…For a muonic atom with a non-zero nuclear spin, it is known that the residual muon spin polarisation at the 1s state is significantly reduced, but even in this case, it could be recovered by using a spin-polarised nuclear target [26,27].…”

Section: To Determine or Constrain How Many Coefficients?mentioning

confidence: 99%

Selecting μ → e conversion targets to distinguish lepton flavour-changing operators

Davidson¹,

Kuno²,

Yamanaka³

2019

Physics Letters B

View full text Add to dashboard Cite

The experimental sensitivity to µ → e conversion on nuclei is set to improve by four orders of magnitude in coming years. However, various operator coefficients add coherently in the amplitude for µ → e conversion, weighted by nucleus-dependent functions, and therefore in the event of a detection, identifying the relevant new physics scenarios could be difficult. Using a representation of the nuclear targets as vectors in coefficient space, whose components are the weighting functions, we quantify the expectation that different nuclear targets could give different constraints. We show that all but two combinations of the 10 Spin-Independent (SI) coefficients could be constrained by future measurements, but discriminating among the axial, tensor and pseudoscalar operators that contribute to the Spin-Dependent (SD) process would require dedicated nuclear calculations. We anticipate that µ → e conversion could constrain 10 to 14 combinations of coefficients; if µ → eγ and µ → eēe constrain eight more, that leaves 60 to 64 "flat directions" in the basis of QED×QCD-invariant operators which describe µ → e flavour change below § Another interesting observable at these experiments is the µ − e − → e − e − in a muonic atom. This process could have not only photonic dipole but also contact interactions, and the atomic number dependence of its reaction rate makes possible to discriminate the type of relevant CLFV interactions [7,8,9]. * * Since the current MEG bound on the dipole coefficients constrains them to be below the sensitivity of the current µ → e conversion bounds, the dipole overlap integral was set to zero in obtaining this Figure.

show abstract