共查询到20条相似文献,搜索用时 15 毫秒
1.
on the basis of calculations performed withi nthe relativistic multiconfiguration Dirac-Fock method, it is shown that the probability of the decay of the 3.5-eV nuclear level in the 229m Th isomer via resonance conversion exceeds the probability of its direct radiative decay by at least a factor of about 600. The possibility of experimentally observing delayed soft photons or alpha particles in the decay of this isomer is discussed. 相似文献
2.
M Auger DJ Auty PS Barbeau E Beauchamp V Belov C Benitez-Medina M Breidenbach T Brunner A Burenkov B Cleveland S Cook T Daniels M Danilov CG Davis S Delaquis R Devoe A Dobi MJ Dolinski A Dolgolenko M Dunford W Fairbank J Farine W Feldmeier P Fierlinger D Franco G Giroux R Gornea K Graham G Gratta C Hall K Hall C Hargrove S Herrin M Hughes A Johnson TN Johnson A Karelin LJ Kaufman A Kuchenkov KS Kumar DS Leonard F Leonard D Mackay R Maclellan M Marino B Mong M Montero Díez AR Müller R Neilson 《Physical review letters》2012,109(3):032505
We report on a search for neutrinoless double-beta decay of ^{136}Xe with EXO-200. No signal is observed for an exposure of 32.5?kg?yr, with a background of ~1.5×10^{-3} kg^{-1}?yr^{-1}?keV^{-1} in the ±1σ region of interest. This sets a lower limit on the half-life of the neutrinoless double-beta decay T_{1/2}^{0νββ}(^{136}Xe)>1.6×10^{25} yr (90% C.L.), corresponding to effective Majorana masses of less than 140-380?meV, depending on the matrix element calculation. 相似文献
3.
The intensities of the transitions to the ground-state and the first excited level of 201Hg in 201Tl decay and the values of the constant log ft are estimated on the basis of an analysis of the relative intensities of the mercury M 4 N 6,7 N 6,7 Auger electron line induced by ? capture and the mercury conversion O 3 line caused by the 1.56-keV nuclear transition. 相似文献
4.
In this work we study the semileptonic decay of ${\bar{B}}_{s}^{0}\to \phi {l}^{+}{l}^{-}$ (l=e, μ, τ) with the QCD sum rule method. We calculate the ${\bar{B}}_{s}^{0}\to \phi $ translation form factors relevant to this semileptonic decay, then the branching ratios of ${\bar{B}}_{s}^{0}\to \phi {l}^{+}{l}^{-}$ (l=e, μ, τ) decays are calculated with the form factors obtained here. Our result for the branching ratio of ${\bar{B}}_{s}^{0}\to \phi {\mu }^{+}{\mu }^{-}$ agree very well with the recent experimental data. For the unmeasured decay modes such as ${\bar{B}}_{s}^{0}\to \phi {e}^{+}{e}^{-}$ and ${\bar{B}}_{s}^{0}\to \phi {\tau }^{+}{\tau }^{-}$ , we give theoretical predictions. 相似文献
5.
S. G. Zemlyanoi D. V. Karaivanov Yu. P. Gangrsky K. P. Marinova B. N. Markov J. Badamsambuu 《Hyperfine Interactions》2010,196(1-3):107-113
Using the method of laser-induced fluorescence in an atomic beam we have measured the hyperfine splitting constants, A and B, of the ground and excited states of the optical transition 4f 76s 2 8S $_{1/2}\to 4f^{7}$ 6s6p 6P5/2 (564.58 nm) for 151???155Eu isotopes. For all isotopes, the magnetic dipole constants of the 6P5/2 atomic level are determined to a precision better than 0.04%. The A and B constants for the ground state 8S7/2 of the radioactive 152,154,155Eu were obtained for the first time with a precision better than 0.5%. Our data along with previous ground state hyperfine structure measurements for the stable europium isotopes allow us to determine the hyperfine anomaly for mentioned Eu isotopes. 相似文献
6.
7.
8.
The state of polarization of the recoil nucleus inγ+3He→π°+3He as well as the asymmetry in the differential cross-section when the initial3He is polarized are studied together with the differential cross-section taking into consideration theS, S′ andD-state admixtures in the nuclear wavefunctions. In view of the considerable spin dependence in the photoproduction amplitudes these observables are found to be quite sensitive to the small admixtures ofS′ andD-states in the nuclear wave-functions. 相似文献
9.
Alexander Yu. Korchin Vladimir A. Kovalchuk 《The European Physical Journal C - Particles and Fields》2012,72(9):1-11
The fully differential angular distribution for the rare flavor-changing neutral current decay $\bar{B}_{d}^{0} \to\bar{K}^{*0} (\to K^{-} \pi^{+}) \mu^{+}\mu^{-} $ is studied. The emphasis is placed on accurate treatment of the contribution from the processes $\bar{B}_{d}^{0} \to\bar{K}^{*0} (\to K^{-} \pi^{+}) V $ with intermediate vector resonances V=??(770),??(782),?(1020),J/??,??(2S),?? decaying into the ?? + ?? ? pair. The dilepton invariant-mass dependence of the branching ratio, longitudinal polarization fraction f L of the $\bar{K}^{*0}$ meson, and forward?Cbackward asymmetry A FB is calculated and compared with data from Belle, CDF and LHCb. It is shown that inclusion of the resonance contribution may considerably modify the branching ratio, calculated in the SM without resonances, even in the invariant-mass region far from the so-called charmonia cuts applied in the experimental analyses. This conclusion crucially depends on values of the unknown phases of the B 0??K ?0 J/?? and B 0??K ?0 ??(2S) decay amplitudes with zero helicity. 相似文献
10.
In this article, we study the $\frac{1} {2}^ -$ and $\frac{3} {2}^ -$ heavy and doubly heavy baryon states $\Sigma _Q \left( {\frac{1} {2}^ - } \right)$ , $\Xi '_Q \left( {\frac{1} {2}^ - } \right)$ , $\Omega _Q \left( {\frac{1} {2}^ - } \right)$ , $\Xi _{QQ} \left( {\frac{1} {2}^ - } \right)$ , $\Omega _{QQ} \left( {\frac{1} {2}^ - } \right)$ , $\Sigma _Q^* \left( {\frac{3} {2}^ - } \right)$ , $\Xi _Q^* \left( {\frac{3} {2}^ - } \right)$ , $\Omega _Q^* \left( {\frac{3} {2}^ - } \right)$ , $\Xi _{QQ}^* \left( {\frac{3} {2}^ - } \right)$ and $\Omega _{QQ}^* \left( {\frac{3} {2}^ - } \right)$ by subtracting the contributions from the corresponding $\frac{1} {2}^ +$ and $\frac{3} {2}^ +$ heavy and doubly heavy baryon states with the QCD sum rules in a systematic way, and make reasonable predictions for their masses. 相似文献
11.
A three-body calculation for the \({^4_{\Lambda} \rm{He}}\) and \({^6_{\Lambda}{\rm H}}\) hypernuclei has been undertaken. The respective cores are \({^4_{\Lambda}{\rm H}}\) . The interactions in the \({^6_{\Lambda}{\rm He}}\) system, modeled as \({^4_{\Lambda} {\rm H+p+n}}\) , are reasonably well known. For example, the p n interaction is well determined by the p n scattering data, the \({^4_{\Lambda}{\rm H}}\) –p interaction can be fitted to the \({^5_{\Lambda}{\rm He}}\) binding energy. The \({^4_{\Lambda}{\rm He}}\) –n interaction can be fitted to α–n scattering data. For the 4He–n system the s-wave can be modeled alternatively as a repulsive potential or as an attractive potential with a forbidden bound state. We explore these alternatives in 6He, because the interaction comes into play in modeling \({^6_{\Lambda}{\rm He}}\) as well as in our \({^4_{\Lambda}{\rm H}}\) + n + n model of \({^6_{\Lambda}{\rm H}}\) , where the valence neutrons are Pauli blocked from the s-shell of the core nucleus. 相似文献
12.
JETP Letters - We have studied spectral evolution of the $$E_{u}^{1}$$ phonon line of a topological insulator Bi2 – xSrxSe3 with temperature. Unlike the Raman-active phonons, the... 相似文献
13.
14.
Andrey Mudrov 《Letters in Mathematical Physics》2012,101(2):157-172
We construct a ${U_\hbar(\mathfrak{sp}(4))}$ -equivariant quantization of the four-dimensional complex sphere ${\mathbb{S}^4}$ regarded as a conjugacy class, Sp(4)/Sp(2) ×?Sp(2), of a simple complex group with non-Levi isotropy subgroup, through an operator realization of the quantum polynomial algebra ${\mathbb{C}_\hbar[\mathbb{S}^4]}$ on a highest weight module of ${U_\hbar(\mathfrak{sp}(4))}$ . 相似文献
15.
CP violation in neutral D meson decays to the CP eigenstates and non-CP eigenstates is studied systematically within the framework of the Cabibbo-Kobayashi-Maskawa model. The nonleptonic two-body decay processes and the decay processes with semileptonic tagging are discussed in detail and the upper bounds of the direct and indirect CP violation in these decay processes are obtained. A method to measure the mixing parameter [(e)\tilde]\tilde{\epsilon} and to separate the direct and indirect CP violation in the decay processes with semileptonic tagging are also discussed. 相似文献
16.
17.
18.
19.
Piyaphat Phoonthong Michiaki Mizuno Kohta Kido Nobuyasu Shiga 《Applied physics. B, Lasers and optics》2014,117(2):673-680
\(^{171}\hbox {Yb}^+\) ions confined within a linear quadrupole trap were laser cooled to below 1 K. The microwave frequency of the hyperfine splitting of the ground state was continuously measured over 6 h. Frequency was corrected by evaluating the systematic shifts in each clock measurement. The absolute microwave frequency was determined as 12 642 812 118.468 2(4) Hz, in strong agreement with previously reported measurements. 相似文献
20.
S Tonegawa K Hashimoto K Ikada YH Lin H Shishido Y Haga TD Matsuda E Yamamoto Y Onuki H Ikeda Y Matsuda T Shibauchi 《Physical review letters》2012,109(3):036401
We report the first observation of cyclotron resonance in the hidden-order phase of ultraclean URu_{2}Si_{2} crystals, which allows the full determination of angle-dependent electron-mass structure of the main Fermi-surface sheets. We find an anomalous splitting of the sharpest resonance line under in-plane magnetic-field rotation. This is most naturally explained by the domain formation, which breaks the fourfold rotational symmetry of the underlying tetragonal lattice. The results reveal the emergence of an in-plane mass anisotropy with hot spots along the [110] direction, which can account for the anisotropic in-plane magnetic susceptibility reported recently. This is consistent with the "nematic" Fermi liquid state, in which itinerant electrons have unidirectional correlations. 相似文献