Koide, Yoshio, Nishiura, Hiroyuki
Based on a neutrino mass matrix model in which a 2-3 symmetry is only broken by a phase parameter, it is investigated how the lepton mixing matrix can deviate from the so-called tribimaximal mixing...
Charged Lepton Mass Spectrum and Supersymmetric Yukawaon Model (2009)
On the basis of the so-called supersymmetric yukawaon model, it is investigated what form of the superpotential W can lead to the observed charged lepton mass spectrum. A simple form of W can...
Yukawaon Model in the Quark Sector and Nearly Tribimaximal Neutrino Mixing (2009)
For the purpose of deriving the observed nearly tribimaximal neutrino mixing, a possible yukawaon model in the quark sector is investigated. Five observable quantities (2 up-quark mass ratios and 3...
Yukawaons in the Charged Lepton Sector (2009)
In the so-called Yukawaon model, the effective Yukawa coupling constants Y_f^{eff} (f=e,\nu,u,d) are given by vacuum expectation values (VEVs) of gauge singlet scalars (Yukawaons) Y_f with 3\times 3...
Based on a new approach (the so-called Yukawaon model) to the mass spectra and mixings, a neutrino mass matrix which is described in terms of the up-quark masses and CKM matrix parameters is...
Charged Lepton Mass Relations in a Supersymmetric Yukawaon Model (2008)
According to an idea that effective Yukawa coupling constants Y_f^{eff} are given vacuum expectation values < Y_f> of fields ("Yukawaons") Y_f as Y_f^{eff}=y_f < Y_f>/\Lambda, a possible...
Maximal CP Violation Hypothesis and a Lepton Mixing Matrix (2008)
Koide, Yoshio, Nishiura, Hiroyuki
Maximal CP violation hypothesis is applied to a simple lepton mixing matrix form U=V_{CKM}^\dagger U_{TB}, which has recently been speculated under an ansatz that U becomes an exact tribimaximal...
Phenomenological Meaning of a Neutrino Mass Matrix Related to Up-Quark Masses (2008)
Recently, a curious neutrino mass matrix has been proposed: it is related to up-quark masses, and it can excellently give a nearly tribimaxial mixing. It is pointed out that, in order to obtain such...
Testable Deviation from Exact Tribimaximal Mixing (2008)
Koide, Yoshio, Nishiura, Hiroyuki
A simple relation U_{MNS}=V_{CKM}^\dagger U_{TB} between the lepton and quark mixing matrices (U_{MNS} and V_{CKM}) is speculated under an ansatz that U_{MNS} becomes an exact tribimaximal mixing...
Neutrino Mass Hierarchies in a Mass Matrix Form Versus its Inverse Form (2008)
A neutrino mass matrix model M_\nu with M_\nu^T =M_\nu and a model with its inverse matrix form \widetilde{M}_\nu = m_0^2 (M_\nu^*)^{-1} can be diagonalized by the same mixing matrix U_\nu. It is...
O(3) Flavor Symmetry and an Empirical Neutrino Mass Matrix (2008)
Based on a new approach to quark and lepton masses, where the mass spectra originate in vacuum expectation values of O(3)-flavor 1+5 (gauge singlet) scalars, a neutrino mass matrix of a new type is...
Empirical Neutrino Mass Matrix Related to Up-Quark Masses (2008)
Based on an approach to quark and lepton masses, where the mass spectra originate in vacuum expectation values of U(3) flavor nonet (gauge singlet) scalars, neutrino masses and mixing are...
U(3)-Flavor Nonet Scalar as an Origin of the Flavor Mass Spectra (2008)
According to an idea that the quark and lepton mass spectra originate in a VEV structure of a U(3)-flavor nonet scalar \Phi, the mass spectra of the down-quarks and charged leptons are investigated....
F-term Induced Flavor Mass Spectrum (2008)
New mechanism of generating flavor mass spectrum is proposed by using an O'Raifeartaigh-type supersymmetry breaking model. A desired bilinear form of fermion mass spectrum is naturally realized...
How to Evade a No-Go Theorem in Flavor Symmetries (2008)
A no-go theorem in flavor symmetries is reviewed. The theorem asserts that we cannot bring any flavor symmetry into mass matrix model in which number of Higgs scalars is, at most, one for each sector...
NNI-Form Quark Mass Matrix Expressed by the Observable Quantities (2007)
It is pointed out that the phase convention of the CKM matrix V affects texture analysis of the quark mass matrices (M u ; M d ) when we try to describe (M u ; M d ) by the observable quantities...
New Origin of a Bilinear Mass Matrix Form (2007)
The charged lepton mass formula can be explained when the masses are propotinal to the squared vacuum expectation values (VEVs) of scalar fields. We introduce U(3) flavor symmetry and its nonet...
Broken SU(3) Flavor Symmetry and Tribimaximal Neutrino Mixing (2007)
Recent work on a lepton mass matrix model based on an SU(3) flavor symmetry which is broken into S_4 is reviewed. The flavor structures of the masses and mixing are caused by VEVs of SU(2)_L-singlet...
Neutrino Mixing based on Mass Matrices with a $2 \leftrightarrow 3$ Symmetry (2007)
Koide, Yoshio, Takasugi, Eiichi
Under the assumption that the $2\leftrightarrow 3$ symmetry is broken only through phases, we give a systematical investigation of possible lepton mass matrix forms without referring to the explicit...
Charged Lepton Mass Formula -- Development and Prospect -- (2007)
The recent devolopment on the charged lepton mass forumula m_e+m_{\mu}+m_{\tau}={2/3}(\sqrt{m_e}+\sqrt{m_\mu}+\sqrt{m_{\tau}})^2 is reviewed. An S_3 or A_4 model will be promising for the mass...
S_4 Flavor Symmetry Embedded into SU(3) and Lepton Masses and Mixing (2007)
Based on an assumption that an S_4 flavor symmetry is embedded into SU(3), a lepton mass matrix model is investigated. A Frogatt-Nielsen type model is assumed, and the flavor structures of the masses...
A_4 Symmetry and Lepton Masses and Mixing (2007)
Stimulated by Ma's idea which explains the tribimaximal neutrino mixing by assuming an A_4 flavor symmetry, a lepton mass matrix model is investigated. A Frogatt-Nielsen type model is assumed, and...
S_3 Symmetry and Neutrino Masses and Mixings (2006)
Based on a universal seesaw mass matrix model with three scalars \phi_i, and by assuming an S_3 flavor symmetry for the Yukawa interactions, the lepton masses and mixings are investigated...
Tribimaximal Neutrino Mixing and a Relation Between Neutrino- and Charged Lepton-Mass Spectra (2006)
Brannen has recently pointed out that the observed charged lepton masses satisfy the relation m_e +m_\mu +m_\tau = {2/3} (\sqrt{m_e}+\sqrt{m_\mu}+\sqrt{m_\tau})^2, while the observed neutrino masses...
Shape of the Unitary Triangle and Phase Conventions of the CKM Matrix (2006)
A shape of the unitary triangle versus a CP violating parameter \delta depends on the phase conventions of the CKM matrix, because the CP violating parameter \delta cannot directly be observed, so...
Permutation Symmetry S_3 and VEV Structure of Flavor-Triplet Higgs Scalars (2005)
A model with flavor-triplet Higgs scalars \phi_i (i=1,2,3)is investigated under a permutation symmetry S_3 and its symmetry breaking. A possible S_3 breaking form of the Higgs potential whose vacuum...
Seesaw Mass Matrix Model of Quarks and Leptons with Flavor-Triplet Higgs Scalars (2005)
In a seesaw mass matrix model M_f = m_L M_F^{-1} m_R^\dagger with a universal structure of m_L \propto m_R, as the origin of m_L (m_R) for quarks and eptons, flavor-triplet Higgs scalars whose vacuum...
Challenge to the Mystery of the Charged Lepton Mass Formula (2005)
Why the charged lepton mass formula m_e +m_\mu +m_\tau = {2/3} (\sqrt{m_e}+\sqrt{m_\mu} +\sqrt{m_\tau})^2 is mysterious is reviewed, and guiding principles to solve the mystery are presented....
Quark and Lepton Mass Matrix Structures Suggested by the Observed Unitary Triangle Shape (2005)
Under the hypothesis that the CP violating phase parameter \delta in the CKM matrix V takes own value so that the radius R(\delta) of the circle circumscribed about the unitary triangle takes its...
Maximal CP Violation Hypothesis and Phase Convention of the CKM Matrix (2004)
The maximal CP violation hypothesis depends on the phase convention of the Cabibbo-Kobayashi-Maskawa matrix. A phase convention which leads to successful prediction under the maximal CP violation...
A radiatively-induced neutrino mass matrix with a simple structure is proposed on the basis of an SU(5) SUSY GUT model with R-parity violation. The model has matter fields $\bar{5}'_{L}+5'_{L}$ in...
Comments on a Flavor Symmetry (2004)
It is pointed out that if a flavor symmetry (a discrete symmetry, a U(1) symmetry, and so on) exists, we cannot obtain the observed CKM quark mixing matrix V_q and MNS lepton mixing matrix U_\ell,...
What Happens If an Unbroken Flavor Symmetry Exists? (2004)
Without assuming any specific flavor symmetry and/or any specific mass matrix forms, it is demonstrated that if a flavor symmetry (a discrete symmetry, a U(1) symmetry, and so on) exists, we cannot...
Within the framework of an SU(5) SUSY GUT model, a possible general form of the neutrino mass matrix induced by R-parity violation is investigated. The model has matter fields \bar{5}'_{L}+5'_{L} in...
Against the conventional picture that the mass matrix forms in the quark sectors will take somewhat different structures from those in the lepton sectors, on the basis of an idea that all the mass...
Radiative Neutrino Masses in a SUSY GUT Model (2003)
Radiatively-induced neutrino mass matrix is investigated within the framework of an SU(5) SUSY GUT model. The model has matter fields of three families \bar{5}_{L(+)i}+5_{L(+)i} in addition to the...
R-Parity Violation in a SUSY GUT Model and Radiative Neutrino Masses (2003)
Within the framework of an SU(5) SUSY GUT model, a mechanism which effectively induces R-parity-violating terms below the unification energy scale M_X is proposed. The model has matter fields...
Universal Texture of Quark and Lepton Mass Matrices (2003)
Koide, Yoshio, Nishiura, Hiroyuki, Matsuda, Koichi, Kikuchi, Tatsuru, Fukuyama, Takeshi
Against the conventional picture that the mass matrix forms in the quark sectors will take somewhat different structures from those in the lepton sectors, a possibility that all the mass matrices of...
An SU(5) SUSY Model with R-Parity Violation and Radiatively Induced Neutrino Masses (2002)
The radiatively induced neutrino mass matrix is investigated on the basis of an SU(5) SUSY model. In order to evade the proton decay, an ansatz based on a discrete symmetry $Z_2$ is assumed:...
Universal Texture of Quark and Lepton Mass Matrices and a Discrete Symmetry Z_3 (2002)
Koide, Yoshio, Nishiura, Hiroyuki, Matsuda, Koichi, Kikuchi, Tatsuru, Fukuyama, Takeshi
Recent neutrino data have been favourable to a nearly bimaximal mixing, which suggests a simple form of the neutrino mass matrix. Stimulated by this matrix form, a possibility that all the mass...
A Unified Description of Quark and Lepton Mass Matrices in a Universal Seesaw Model (2002)
In the democratic universal seesaw model, the mass matrices are given by \bar{f}_L m_L F_R + \bar{F}_L m_R f_R + \bar{F}_L M_F F_R (f: quarks and leptons; F: hypothetical heavy fermions), m_L and m_R...
Radiatively Induced Neutrino Mass Matrix in a SUSY GUT Model with R-Parity Violation (2002)
In order to evade the proton decay which appears when the Zee model is embedded into a SUSY GUT scenario with R-parity violation, a new idea based on a discrete Z_2 symmetry is proposed. Under the...
Prospect of the Zee model (2002)
The Zee model is one of promising models of neutrino mass generation mechanism. However, the original Zee model is not on the framework of the ground unification scenario, and moreover, it is...
New Trends in the Zee Model (2001)
Recent trends in the Zee model are reviewed. Especially, the importance of a serious constraint in the Zee model, sin^2 2\theta_{solar} =1.0, is pointed out.
Can the Zee Model Explain the Observed Neutrino Data? (2001)
The eigenvalues and mixing angles in the Zee model are investigated parameter-independently. When we require |\Delta m^2_{12}/\Delta m^2_{23}| \ll 1 in order to understand the solar and atmospheric...
Lepton Flavor Violating Z Decays in the Zee Model (2001)
Ghosal, Ambar, Koide, Yoshio, Fusaoka, Hideo
We calculate lepton flavor violating (LFV) Z decays Z \to {{e_i^\pm}}e_j^\mp (i, j = e, \mu, \tau ; i\neq j) in the Zee model keeping in view the radiative leptonic decays e_i\to e_j\gamma (i = \mu,...
Evolution of the Yukawa coupling constants and seesaw operators in the universal seesaw model (2000)
The general features of the evolution of the Yukawa coupling constants and seesaw operators in the universal seesaw model with det M_F=0 are investigated. Especially, it is checked whether the model...
Bimaximal Neutrino Mixing in a Zee-type Model with Badly Broken Flavor Symmetry (2000)
A Zee-type neutrino mass matrix model with a badly broken horizontal symmetry SU(3)_H is investigated. By putting a simple ansatz on the symmetry breaking effects of SU(3)_H for transition matrix...
Democratic Universal Seesaw Model with Three Light Sterile Neutrinos (2000)
Based on the "democratic" universal seesaw model, where mass matrices $M_f$ of quarks and leptons f_i (f=u,d,\nu,e; i=1,2,3) are given by a seesaw form M_f\simeq -m_L M_F^{-1} m_R, and m_L and m_R...
Quark and Lepton Mass Matrices with a Cyclic Permutation Invariant Form (2000)
As an attempt to give an unified description of quark and lepton mass matrices M_f, the following mass matrix form is proposed: the form of the mass matrices are invariant under a cyclic permutation...
SO(10) \times SO(10) Universal Seesaw Model and its Intermediate Mass Scales (1999)
On the basis of the universal seesaw mass matrix model, which is a promising model of the unified description of the quark and lepton mass matrices, the behaviors of the gauge coupling constants and...
Universal Seesaw Mass Matrix Model with an S_3 Symmetry (1999)
Stimulated by the phenomenological success of the universal seesaw mass matrix model, where the mass terms for quarks and leptons f_i (i=1,2,3) and hypothetical super-heavy fermions F_i are given by...
Universal Seesaw Mass Matrix Model and SO(10)\times SO(10) Unification (1998)
On the universal seesaw mass matrix model, which is a promising model of the unified description of the quark and lepton mass matrices, the behaviors of the gauge coupling constants and intermediate...
Universal Seesaw Mass Matrix Model with Three Light Pseudo-Dirac Neutrinos (1998)
A universal seesaw mass matrix model, which gives successful description of quark mass matrix in terms of lepton masses, yields three "sterile" neutrinos \nu^s_{i}, which compose pseudo-Dirac...
Universal Seesaw Mass Matrix Model and Neutrino Phenomenology (1998)
Stimulated by the recent development of the ``universal seesaw mass matrix model", an application of the model to the neutrino mass matrix is investigated: For the charged lepton and down-quark...
New Aspects on a Seesaw Mass Matrix Model (1998)
Recent development of the universal seesaw mass matrix model is reviewed. The model was proposed in order to explain why quark and lepton masses are so small compared with the electroweak scale...
Coupling Constants Evolution in a Universal Seesaw Mass Matrix Model (1998)
Stimulated by a universal seesaw mass matrix model which can successfully give quark masses and CKM matrix elements in terms of charged lepton masses, the evolution of the seesaw mass matrices is...
Updated Estimate of Running Quark Masses (1997)
Stimulated by recent development of the calculation methods of the running quark masses $m_q(\mu)$ and renewal of the input data, for the purpose of making a standard table of $m_q(\mu)$ for...
Neutrino Masses and Mixings in a Universal Seesaw Mass Matrix Model (1997)
Neutrino masses and mixings are investigated on the basis of a universal seesaw mass matrix model, in which quark (except for top) and charged lepton mass matrices M_f and neutrino mass matrix M_\nu...
Abnormal Structure of Fermion Mixings in a Seesaw Quark Mass Matrix Model (1997)
It is pointed out that in a seesaw quark mass matrix model which yields a singular enhancement of the top-quark mass, the right-handed fermion-mixing matrix U_R^u for the up-quark sector has a...
Updated Running Quark Mass Values (1997)
The running quark masses at various energy scales are evaluated by using the mass renormalization equations systematically. Also, those at energy scales higher than m_Z are evaluated by using the...
Democratic Seesaw Mass Matrix Model and New Physics (1997)
A seesaw mass matrix model is reviewed as a unification model of quark and lepton mass matrices. The model can understand why top-quark mass m_t is so singularly enhanced compared with other quark...
NNI-Form Quark Mass Matrix Expressed by the Observable Quantities (1997)
It is pointed out that the phase convention of the CKM matrix V affects texture analysis of the quark mass matrices (M_u, M_d) when we try to describe (M_u, M_d) by the observable quantities (quark...
Flavor-Changing Neutral Currents Induced by the Democratic Seesaw Mass Matrix (1997)
Flavor-changing neutral currents (FCNC) are studied on the basis of a ``democratic seesa'' mass matrix model, which yields a singular enhancement of the top-quark mass m_t and can give reasonable...
Analytical Expressions of Masses and Mixings in a Democratic Seesaw Mass Matrix Model (1996)
On the basis of a seesaw-type mass matrix model $M_f\simeq m_L M_F^{-1} m_R$ for quarks and leptons $f$, analytical expressions of the masses and mixings of the fermions $f$ are investigated. Here,...
Neutrino Mixing in a Democratic-Seesaw-Mass-Matrix Model (1996)
On the basis of a seesaw-type mass matrix model for quarks and leptons, $M_f \simeq m_L M_F^{-1} m_R$, where $m_L\propto m_R$ are universal for $f=u,d,\nu$ and $e$ (up-quark-, down-quark-, neutrino-...
A Democratic Seesaw Quark Mass Matrix Related to the Charged Lepton Masses (1996)
We investigate a seesaw type mass matrix $M_f\simeq m_L M_F^{-1} m_R$ for quarks and leptons, $f$, under the assumptions that the matrices $m_L$ and $m_R$ have common structures for the quarks and...
Democracy of Families and Neutrino Mass Matrix (1995)
On the basis of a seesaw-type mass matrix model for quarks and leptons, $M_f \simeq m_L M_F^{-1} m_R$, where $m_L\propto m_R$ are universal for $f=u,d,\nu$ and $e$ (up-quark-, down-quark-, neutrino-...
U(3)-Family Nonet Higgs Boson and its Phenomenology (1995)
Koide, Yoshio, Tanimoto, Morimitu
In a model where quark and lepton masses and family-mixings are caused not by a variety of Yukawa couplings $y_{ij}$ ($i,j=1,2,3$: family indices) with one vacuum expectation value (VEV)...
New Physics from U(3)-Family Nonet Higgs Boson Scenario (1995)
Being inspired by a phenomenological success of a charged lepton mass formula, a model with U(3)-family nonet Higgs bosons is proposed. Here, the Higgs bosons $\phi_L$ ($\phi_R$) couple only between...
HAYASHI, Takemi, Koide, Yoshio, Matsuda, Masahisa, Tanimoto, Morimitsu, Wakaizumi, Seiichi
We study the electric dipole moments(EDM) of the neutron and the electron in the two-Higgs-doublet model, in the case that $CP$ symmetry is violated maximally in the neutral Higgs sector. We take...
Table of Running Quark Mass Values : 1994 (1994)
Running quark mass values $m_q(\mu)$ at some typical energy scales ($\mu=1$ GeV, $\mu=m_W$, and so on) are reviewed. The values depend considerably on the value of $\Lambda_{\overline{MS}}$,...
Seesaw-Type Quark and Lepton Mass Matrices and U(3)-Family Nonet Higgs Bosons (1994)
A unified mass matrix model of quarks and leptons with a seesaw-type form $M_f=m M_F^{-1} m$ is proposed on the basis of a non-standard Higgs scenario. The matrix $m$ is provided by U(3)-family nonet...
Neutron Electric Dipole Moment in Two Higgs Doublet Model (1994)
Hayashi, Tkemi, Koide, Yoshio, Matsuda, Masahisa, Tanimoto, Morimitsu
We study the effect of the "chromo-electric" dipole moment on the electric dipole moment(EDM) of the neutron in the two Higgs doublet model. We systematically investigate the Weinberg's operator...
Phenomenological Quark Mass Matrix Model with Two Adjustable Parameters (1993)
A phenomenological quark mass matrix model which includes only two adjustable parameters is proposed from the point of view of the unification of quark and lepton mass matrices. The model can provide...
Esophageal Cancer in the Intermediate Stage (1982)
ISONO, KAICHI, KOIDE, YOSHIO, SATO, HIROSHI
When we consider the prognosis of esophageal carcinoma, we come to the conclusion that the less the invasion of the disease, the better the prognosis can be. It is quite reasonable that the prognosis...
T1n0乳癌再発例の検討 : 乳房温存療法術後残存乳房再発に対する一考察
宮沢, 幸正, ミヤザワ, ユキマサ, Miyazawa, Yukimasa, MIYAZAWA, Yukimasa, 朱, 琮杰, CHU, Chung Chieh, ...
1965年より1993年に当科で手術を施行した全乳癌症例中両側乳癌を除く女子乳癌手術例で病理型のはっきりしているものは466例であり,...
T1n0乳癌再発例の検討 : 乳房温存療法術後残存乳房再発に対する一考察
宮沢, 幸正, 朱, 琮杰, 吉田, 雅博, 大渕, 徹, 松崎, 弘志, 小出, 義雄, ...
1965年より1993年に当科で手術を施行した全乳癌症例中両側乳癌を除く女子乳癌手術例で病理型のはっきりしているものは466例であり,...
胸部食道癌の集学的治療の研究 : 3領域郭清例における補助療法の検討
小出, 義雄, コイデ, ヨシオ, Koide, Yoshio, KOIDE, Yoshio
胸部食道癌に対する集学的治療の成績向上を目的として, 3領域郭清の治療成績の評価,...
胸部食道癌の集学的治療の研究 : 3領域郭清例における補助療法の検討
小出, 義雄, コイデ, ヨシオ, Koide, Yoshio, KOIDE, Yoshio
胸部食道癌に対する集学的治療の成績向上を目的として, 3領域郭清の治療成績の評価,...
宮沢, 幸正, ミヤザワ, ユキマサ, MIYAZAWA, Yukimasa, 朱, 琮杰, CHU, Chung Chieh, 窪澤, 仁, ...
骨, 軟骨化生を伴う乳癌は,...
宮沢, 幸正, ミヤザワ, ユキマサ, MIYAZAWA, Yukimasa, 朱, 琮杰, CHU, Chung Chieh, 窪澤, 仁, ...
骨, 軟骨化生を伴う乳癌は,...