Large Isospin-Mixing Matrix Element inC12

1972 ◽  
Vol 29 (6) ◽  
pp. 376-379 ◽  
Author(s):  
W. J. Braithwaite ◽  
J. E. Bussoletti ◽  
F. E. Cecil ◽  
G. T. Garvey
Keyword(s):  
2015 ◽  
Vol 30 (05) ◽  
pp. 1550019 ◽  
Author(s):  
Jun Iizuka ◽  
Teruyuki Kitabayashi ◽  
Yuki Minagawa ◽  
Masaki Yasuè

CP violation in neutrino interactions is described by three phases contained in Pontecorvo–Maki–Nakagawa–Sakata mixing matrix (U PMNS ). We argue that the phenomenologically consistent result of the Dirac CP violation can be obtained if U PMNS is constructed along bipair neutrino mixing scheme, namely, requiring that |U12| = |U32| and |U22| = |U23| (case 1) and |U12| = |U22| and |U32| = |U33| (case 2), where Uij stands for the i × j matrix element of U PMNS . As a result, the solar, atmospheric and reactor neutrino mixing angles θ12, θ23 and θ13, respectively, are correlated to satisfy cos 2θ12 = sin 2 θ23 - tan 2 θ13 (case 1) or cos 2θ12 = cos 2 θ23 - tan 2 θ13 (case 2). Furthermore, if Dirac CP violation is observed to be maximal, θ23 is determined by θ13 to be: [Formula: see text] (case 1) or [Formula: see text] (case 2). For the case of non-maximal Dirac CP violation, we perform numerical computation to show relations between the CP-violating Dirac phase and the mixing angles.


1996 ◽  
Vol 367 (1-4) ◽  
pp. 45-49 ◽  
Author(s):  
M.J Iqbal ◽  
Xuemin Jin ◽  
Derek B Leinweber

1995 ◽  
Vol 10 (22) ◽  
pp. 3125-3141 ◽  
Author(s):  
A.A. PIVOVAROV

The leading αs corrections to the B parameter of the [Formula: see text] mixing matrix element are calculated within the sum rules method. Numerical estimates given in the framework of the factorization hypothesis for vacuum expectation values of four-quark local operators show a decrease of the [Formula: see text] matrix element from the factorized value by about 20% at the normalization point μ~1 GeV. The nonanalytical dependence of the B parameter on the kaon mass mK (~a, log mK) is discovered in the chiral limit.


1978 ◽  
Vol 31 (4) ◽  
pp. 239 ◽  
Author(s):  
FC Barker ◽  
Nasima Ferdous

Level parameters for the 3+ doublet at about 19 MeV in "Be are obtained from a two-level R-matrix fit to the 7Li+p 5P3 phase shift, using the restrictions of the two-state isospin mixing model. The energy of the lower level is appreciably below the accepted value. Predicted contributions from the 3 + levels to the cross sections for the reactions 7Li(p, n), 7Li(p, y), lOBed, ex) and 9Be(d, t) are compared with measured values, and qualitative agreement is obtained. The new values of the level parameters give agreement with values of the isospin mixing matrix element and of the excitation energy difference of the 3 +, T = 1 states in "Li and "Be, calculated assuming that the charge-dependent nteraction is purely Coulomb.


1995 ◽  
Vol 10 (22) ◽  
pp. 1577-1582 ◽  
Author(s):  
T. KURIMOTO

It is shown that the complex phase of [Formula: see text] mixing matrix element is the same as that of the standard model up to the minor correction of the order of (mc/mt)2 or less in the SUSY standard model. This conclusion is valid as far as the Yukawa coupling constants are perturbative and realistic, and can be available for other realistic models where generation mixing and CP-violation are solely due to Yukawa interaction among quarks and Higgs doublets.


2007 ◽  
Vol 2007 ◽  
pp. 1-15 ◽  
Author(s):  
Alexander Merle ◽  
Werner Rodejohann

We consider the possibility to gain information on the lepton mixing matrix element|Ue3|from an improved experimental limit on the effective neutrino mass governing neutrinoless double beta decay. We show that typically a lower limit on|Ue3|as a function of the smallest neutrino mass can be set. Furthermore, we give the values of the sum of neutrino masses and|Ue3|which are allowed and forbidden by an experimental upper limit on the effective mass. Alternative explanations for neutrinoless double beta decay, Dirac neutrinos or unexplained cosmological features would be required if future measurements showed that the values lie in the respective regions. Moreover, we show that a measurement of|Ue3|from neutrinoless double beta decay is very difficult due to the expected errors on the effective mass and the oscillation parameters.


2014 ◽  
Vol 89 (5) ◽  
Author(s):  
M. Ablikim ◽  
M. N. Achasov ◽  
X. C. Ai ◽  
O. Albayrak ◽  
D. J. Ambrose ◽  
...  

1980 ◽  
Vol 58 (2) ◽  
pp. 249-254
Author(s):  
J. J. Bevelacqua

Parity-mixing matrix elements for ΔT = 0 and ΔT = 1 transitions are calculated for selected transitions below 30 MeV excitation energy in the 4He system. The effective potential of Box, McKellar, Pick, and Lassey is utilized in the calculations. The results are based on detailed 4He wave functions which are calculated in a [Formula: see text] model space. The calculated parity-mixing matrix elements are in qualitative agreement with those predicted on the basis of a least-squares fit to 2 ≤ A ≤ 181 data by Desplanques and Missimer. The ΔT = 0 matrix element is calculated between the (0+,0)20.1 MeV level and the (0−,0)21.1 MeV level, while the ΔT = 1 matrix element is evaluated between the (1+,0) 25.5 MeV level and the (1−,1) 27.4 MeV state. The ΔT = 0 and ΔT = 1 calculations lead to parity-mixing matrix elements of −0.014 and +0.049 eV, respectively. These matrix elements correspond to parity-mixed components which are 10−8 smaller than the dominant parity component of an energy level. The parity-non-conserving (PNC) transitions lead to circular polarizations of 1.2 × 10−7 for the (1+,0) 25.5 MeV level and −2.2 × 10−8 for the (1−,1) 27.4 MeV level. The inclusion of a neutral current enhancement factor of about 10 increases the ΔT = 1 parity-mixing matrix element by about a factor of two.


1989 ◽  
Vol 222 (2) ◽  
pp. 293-297 ◽  
Author(s):  
P. Colangelo ◽  
G. Nardulli ◽  
N. Paver

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