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Related papers: CP and Flavour in Effective Type I String Models

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We study the contributions of supersymmetric models with a $U(1)$ horizontal symmetry and only spontaneous CP breaking to various lepton flavor observables, such as $\mu \to e\gamma$ and the electron electric dipole moment. We show that…

High Energy Physics - Phenomenology · Physics 2021-12-16 Daniel Aloni , Pouya Asadi , Yuichiro Nakai , Matthew Reece , Motoo Suzuki

A review of CP violation from the Standard Model to strings is given which includes a broad landscape of particle physics models, encompassing the non-supersymmetric 4D extensions of the standard model, and models based on supersymmetry, on…

High Energy Physics - Phenomenology · Physics 2008-11-26 Tarek Ibrahim , Pran Nath

I show that the effective action of string compactifications has a structure that can naturally solve the supersymmetric flavour and CP problems. At leading order in the g_s and \alpha' expansions, the hidden sector factorises. The moduli…

High Energy Physics - Theory · Physics 2009-06-10 Joseph P. Conlon

We analyse a possible connection between CP violations in the quark and lepton sectors, parametrised by the CKM and PMNS phases. If one assumes that CP breaking arises from complex Yukawa couplings, both in the quark and lepton sectors, the…

High Energy Physics - Phenomenology · Physics 2021-09-01 João M. Alves , Francisco J. Botella , Gustavo C. Branco , Fernando Cornet-Gomez , Miguel Nebot

The weakly-coupled heterotic string is known to have problems of dilaton/moduli stabilization, supersymmetry breaking (by hidden-sector gaugino condensation), gauge coupling unification (or the Newton's constant), QCD axion, as well as…

High Energy Physics - Theory · Physics 2007-05-23 Yi-Yen Wu

The flavor changing and CP violating phenomena predicted in supersymmetric unified theories as a consequence of the large top quark Yukawa coupling, are investigated in the quark sector and compared with related phenomena in the lepton…

High Energy Physics - Phenomenology · Physics 2009-10-09 Riccardo Barbieri , Lawrence Hall , Alessandro Strumia

Non-universality in the soft breaking terms is a common feature in most superstring inspired SUSY models. This property is required to obtain sizeable CP violation effects from SUSY and, on the other hand, can be used to avoid the Electric…

High Energy Physics - Phenomenology · Physics 2009-10-31 Shaaban Khalil , Tatsuo Kobayashi , Oscar Vives

We reconsider the origin of CP violation in fundamental theory. Existing string models of spontaneous CP violation make ambiguous predictions, due to the arbitrariness of CP transformation and the apparent non-invariance of the results…

High Energy Physics - Phenomenology · Physics 2014-11-17 Thomas Dent

We investigate the possibility of large CP- violating phases in the soft breaking terms derived in superstring models. The bounds on the electric dipole moments (EDM's) of the electron and neutron are satisfied through cancellations…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Brhlik , L. Everett , G. L. Kane , J. Lykken

We analyse the CP problem in the context of a supersymmetric extension of the standard model with universal strength of Yukawa couplings. A salient feature of these models is that the CP phases are constrained to be very small by the…

High Energy Physics - Phenomenology · Physics 2009-09-25 G. C. Branco , M. E. Gomez , S. Khalil , A. M. Teixeira

We consider a spontaneously broken gauge theory based on the standard model (SM) group G = SU(2) x U(1) with scalar fields that carry arbitrary representations of G, and we investigate some general properties of the charged and neutral…

High Energy Physics - Phenomenology · Physics 2014-11-17 W. Bernreuther , O. Nachtmann

We demonstrate that in effective theories arising from a class of N=1 fluxless compactifications of M-theory on a G2 manifold with low energy supersymmetry, CP-violating phases do not appear in the soft-breaking Lagrangian except via the…

High Energy Physics - Phenomenology · Physics 2011-01-26 Gordon Kane , Piyush Kumar , Jing Shao

The two principles of spontaneous CP violation and natural flavor conservation can be realized in the $SU(2)_{L}\times U(1)_{Y}$ model with two Higgs doublets. In particular, this model provides a consistent application to the CP violating…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yue-Liang Wu

We analyse the properties of generic models based on an SU(3) family symmetry providing a full description of quark charged lepton and neutrino masses and mixing angles. We show that a precise fit of the resulting fermion textures is…

High Energy Physics - Phenomenology · Physics 2009-11-10 Graham G. Ross , Liliana Velasco-Sevilla , Oscar Vives

We study the contraints on non-flavour-blind soft supersymmetry breaking terms coming from flavour and CP violating processes in the presence of hierarchical Yukawa couplings, and quantify how much these constraints are weakened in the…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. H. Chankowski , K. Kowalska , S. Lavignac , S. Pokorski

We propose a model of spontaneous CP violation to address the strong CP problem in warped extra dimensions that relies on sequestering flavor and CP violation. We assume that brane-localized Higgs Yukawa interactions respect a U(3) flavor…

High Energy Physics - Theory · Physics 2009-01-06 Clifford Cheung , A. Liam Fitzpatrick , Lisa Randall

We formulate general conditions under which the strong CP problem is solved by spontaneous CP violation. Quark-mass matrix elements are polynomials in the CP-breaking order parameters, engineered such that their determinant is a real…

High Energy Physics - Phenomenology · Physics 2024-08-16 Ferruccio Feruglio , Matteo Parriciatu , Alessandro Strumia , Arsenii Titov

The possibility of spontaneous breaking of CP symmetry by the expectation values of orbifold moduli is investigated with particular reference to $CP$ violating phases in soft supersymmetry breaking terms. The effect of different mechanisms…

High Energy Physics - Theory · Physics 2014-11-18 D. Bailin , G. V. Kraniotis , A. Love

The suppression of flavor and CP violation in supersymmetric theories may be due to the mechanism responsible for the structure of the Yukawa couplings. We study model independently the compatibility between low energy flavor and CP…

High Energy Physics - Phenomenology · Physics 2009-02-23 Yasunori Nomura , Daniel Stolarski

We study the lepton-flavor violation processes tau ->mu gamma and mu->e gamma in two different examples of models with non-universal soft breaking terms derived from strings. We show that the predictions are quite different from those of…

High Energy Physics - Phenomenology · Physics 2010-02-03 Daniel F. Carvalho , Mario E. Gomez , Shaaban Khalil