ترغب بنشر مسار تعليمي؟ اضغط هنا

Slepton Mass Matrices, mu -> e gamma Decay and EDM in SUSY S4 Flavor Model

111   0   0.0 ( 0 )
 نشر من قبل Hajime Ishimori Dr.
 تاريخ النشر 2010
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

We discuss slepton mass matrices in the $S_4$ flavor model with SUSY SU(5) GUT. By considering the gravity mediation within the framework of supergravity theory, we estimate the SUSY breaking terms in the slepton mass matrices, which contribute to the $mu rightarrow e + gamma$ decay. We obtain a lower bound for the ratio of $murightarrow egamma$ as $10^{-13}$ if $m_{text{SUSY}}$ and $m_{1/2}$ are below 500GeV. The off diagonal terms of slepton mass matrices also contribute to EDM of leptons. The predicted electron EDM is around $10^{-29}-10^{-28}$cm. Our predictions are expected to be tested in the near future experiment.



قيم البحث

اقرأ أيضاً

We present a flavor model of quarks and leptons with the non-Abelian discrete symmetry $S_4$ in the framework of the SU(5) SUSY GUT. Three generations of $bar 5$-plets in SU(5) are assigned to ${bf 3}$ of $S_4$ while the first and second generations of 10-plets in SU(5) are assigned to ${bf 2}$ of $S_4$, and the third generation of 10-plet is assigned to ${bf 1}$ of $S_4$. Right-handed neutrinos are also assigned to ${bf 2}$ for the first and second generations and ${bf 1}$ for the third generation. We predict the Cabibbo angle as well as the tri-bimaximal mixing of neutrino flavors. We also predict the non-vanishing $U_{e3}$ of the neutrino flavor mixing due to higher dimensional mass operators. Our predicted CKM mixing angles and the CP violation are consistent with experimental values. We also study SUSY breaking terms in the slepton sector. Our model leads to smaller values of flavor changing neutral currents than the present experimental bounds.
We study lepton flavor models with the $S_4$ flavor symmetry. We construct simple models with smaller numbers of flavon fields and free parameters, such that we have predictions among lepton masses and mixing angles. The model with a $S_4$ triplet fl avon is not realistic, but we can construct realistic models with two triplet flavons, or one triplet and one doublet flavons.
There are many models with non-universal soft SUSY breaking sfermion mass parameters at the grand unification scale. Even in the mSUGRA model scalar mass unification might occur at a scale closer to M_Planck, and renormalization effects would cause a mass splitting at M_GUT. We identify an experimentally measurable quantity Delta that correlates strongly with delta m^2 = m^2_{selectron_R}(M_GUT) - m^2_{selectron_L}(M_GUT), and which can be measured at electron-positron colliders provided both selectrons and the chargino are kinematically accessible. We show that if these sparticle masses can be measured with a precision of 1% at a 500 GeV linear collider, the resulting precision in the determination of Delta may allow experiments to distinguish between scalar mass unification at the GUT scale from the corresponding unification at Q ~ M_Planck. Experimental determination of Delta would also provide a distinction between the mSUGRA model and the recently proposed gaugino-mediation model. Moreover, a measurement of Delta (or a related quantity Delta) would allow for a direct determination of delta m^2.
We construct a low-scale seesaw model to generate the masses of active neutrinos based on $S_4$ flavor symmetry supplemented by the $Z_2 times Z_3 times Z_4 times Z_{14}times U(1)_L$ group, capable of reproducing the low energy Standard model (SM) fe rmion flavor data. The masses of the SM fermions and the fermionic mixings parameters are generated from a Froggatt-Nielsen mechanism after the spontaneous breaking of the $S_4times Z_2 times Z_3 times Z_4 times Z_{14}times U(1)_L$ group. The obtained values for the physical observables of the quark and lepton sectors are in good agreement with the most recent experimental data. The leptonic Dirac CP violating phase $de _{CP}$ is predicted to be $259.579^circ$ and the predictions for the absolute neutrino masses in the model can also saturate the recent constraints.
We study muon pair production $ e^+ e^- to mu^+ mu^-$ in the noncommutative(NC) extension of the standard model using the Seiberg-Witten maps of this to the second order of the noncommutative parameter $Theta_{mu u}$. Using $mathcal{O}(Theta^2)$ Fey nman rules, we find the $mathcal{O}(Theta^4)$ cross section(with all other lower order contributions simply cancelled) for the pair production. The momentum dependent $mathcal{O}(Theta^2)$ NC interaction significantly modifies the cross section and angular distributions which are different from the commuting standard model. We study the collider signatures of the space-time noncommutativity at the International Linear Collider(ILC) and find that the process $ e^+ e^- to mu^+ mu^-$ can probe the NC scale $Lambda$ in the range $0.8 - 1.0$ TeV for typical ILC energy ranges.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا