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Related papers: Should Squarks Be Degenerate?

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We discuss the supersymmetric O(alpha_s) QCD corrections to e+ e- -> squark_i + antisquark_j (i,j = 1,2) and to squark_i -> q' + chargino_j, q + neutralino_k (i,j = 1,2; k = 1...4) within the Minimal Supersymmetric Standard Model. In…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Bartl , H. Eberl , S. Kraml , W. Majerotto , W. Porod

It is argued that the topcolor models recently proposed by Hill [1] may face significant constraints from flavor-changing neutral current processes (such as $B-\bar{B}$ mixing) unless the mixing angles between down-type quarks are small.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Dimitris Kominis

Rare flavour-changing neutral-current transitions of the type $s \to d \ell^+\ell^-(\nu\bar\nu)$ and $b \to s \ell^+\ell^-(\nu\bar\nu)$ are analysed in supersymmetric extensions of the Standard Model with generic flavour couplings. It is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gino Isidori

In this letter we propose a multi-Higgs extension of the standard model with Abelian and non-Abelian discrete symmetries in which the mass matrices of the charged fermions obtained from renormalizable interactions are diagonal. Corrections…

High Energy Physics - Phenomenology · Physics 2009-04-06 A. C. B. Machado , V. Pleitez

We show that the decay gluino -> stop_1 b-quark W is important and can even be dominant in the region of parameter space where it is kinematically allowed. We discuss phenomenological implications within the Minimal Supersymmetric Standard…

High Energy Physics - Phenomenology · Physics 2011-01-27 W. Porod

QCD corrections to the gluino induced contribution to b --> s gamma are shown to be important in order to extract reliable bounds on the off-diagonal elements of the squark mass matrices.

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Greub , T. Hurth , D. Wyler

Within the broad context of quark-lepton unification, we investigate the implications of broken continuous family symmetries which result from requiring that in the limit of exact symmetry, the Dirac mass matrices yield hierarchical masses…

High Energy Physics - Phenomenology · Physics 2010-10-27 Lisa Everett , Pierre Ramond

Quark flavor mixing may originate in the soft breaking of horizontal symmetries. Those symmetries, which in the simplest case are three family U(1) groups, are obeyed only by the dimension-4 Yukawa couplings and lead, when unbroken, to the…

High Energy Physics - Phenomenology · Physics 2009-11-10 W. Grimus , L. Lavoura

We give explicit expressions for the amplitudes associated with the supersymmetric contributions to the process: b -> s gamma in the context of SUSY extensions of Standard Model with non-universal soft SUSY breaking terms. From experimental…

High Energy Physics - Phenomenology · Physics 2011-09-13 M. B. Causse , J. Orloff

An inverted mass hierarchy in the squark sector, as in so-called "natural supersymmetry", requires non-universal boundary conditions at the mediation scale of supersymmetry breaking. We propose a formalism to define such boundary conditions…

High Energy Physics - Phenomenology · Physics 2015-06-18 Felix Brümmer , Sabine Kraml , Suchita Kulkarni , Christopher Smith

We investigate couplings of squarks to gauge and Higgs-bosons within the framework of non-minimal flavour violation in the Minimal Supersymmetric Standard Model. Introducing non-diagonal elements in the mass matrices of squarks, we first…

High Energy Physics - Phenomenology · Physics 2014-11-21 Matthias Bruhnke , Björn Herrmann , Werner Porod

We apply the quark delocalization and color screening model to nucleon-baryon scattering. A semi-quantitative fit to N-N, N-Lambda and N-Sigma phase shifts and scattering cross sections is obtained without invoking meson exchange. Quarks…

Nuclear Theory · Physics 2009-09-25 Guang-han Wu , Jia-Lun Ping , Li-jian Teng , Fan Wang , T. Goldman

Squark and gluino decays are governed by the same mixing matrices as the contributions to flavour violating loop transitions of B-mesons. This allows for possible direct correlations between flavour non-diagonal observables in B and…

High Energy Physics - Phenomenology · Physics 2014-11-20 Tobias Hurth , Werner Porod

Renormalization effects of large baryon-nonconserving Yukawa couplings $\lambda^{\prime\prime}_{ijk} \overline{U_i} \overline{D_j} \overline{D_k}$ lower the right handed squark masses keeping the left-handed squark masses virtually…

High Energy Physics - Phenomenology · Physics 2014-11-17 Mar Bastero-Gil , Biswajoy Brahmachari

The 331 model, an extension of the standard electroweak theory to $SU(3)_L\times U(1)_X$, naturally predicts three families of quarks and leptons via the requirement of anomaly cancellation. This is accomplished by making one of the quark…

High Energy Physics - Phenomenology · Physics 2010-11-01 James T. Liu

We study the contribution of the gluino-squark mediated flavor changing process for the CP violation in $b\to s$ and $b\to d$ transitions facing on recent experimental data. The mass insertion parameters of squarks are constrained by the…

High Energy Physics - Phenomenology · Physics 2013-03-14 Yusuke Shimizu , Morimitsu Tanimoto , Kei Yamamoto

We calculate the electroweak-like one-loop supersymmetric contributions to the rare and flavor-violating decay of the top quark into a charm quark and a gauge boson: $t->c V$, with $V=\gamma,Z,g$. We consider loops of both charginos and…

High Energy Physics - Phenomenology · Physics 2009-10-30 Jorge L. Lopez , D. V. Nanopoulos , Raghavan Rangarajan

The discrete non-Abelian symmetry $A_4$, valid at some high-energy scale, naturally leads to degenerate neutrino masses, without spoiling the hierarchy of charged-lepton masses. Realistic neutrino mass splittings and mixing angles (one of…

High Energy Physics - Phenomenology · Physics 2009-09-17 K. S. Babu , Ernest Ma , J. W. F. Valle

The flavor changing neutral current processes $K_L \to \pi^0 e^+ e^-$, $B \to X_s e^+ e^-$ and $B \to X_s \mu^+ \mu^-$ are studied within the minimal supersymmetric extension of the Standard Model. We first examine the rates for these decay…

High Energy Physics - Phenomenology · Physics 2009-10-28 Peter Cho , Mikolaj Misiak , Daniel Wyler

In the scenario with Z mediated flavor changing neutral current occurring at the tree level due to the addition of a vector-like isosinglet down-type quark d' to the SM particle spectrum, we perform a chi square fit using the flavor physics…

High Energy Physics - Phenomenology · Physics 2012-12-07 Ashutosh Kumar Alok , Shireen Gangal