Singlet Fermion Assisted Dominant Seesaw with Lepton Flavor and Number Violations and Leptogenesis

In a recent review Mohapatra has discussed how type-I seesaw mechanism suppressed by fine tuning of Yukawa couplings, or specific textures of associated fermion mass matrices, can form the basis of neutrino masses in TeV scale $W_R$ boson models. In this paper we review recent works in another class of theories where the added presence of fermion singlets manifesting as sterile neutrinos render the type-I seesaw contribution vanishing but extended seesaw dominant where the light neutrino mass formula is same as the classic inverse seesaw but all massive neutrinos are Majorana fermions. We also show domunance of linear seesaw, or double seesaw, or type-II seesaw in due to cancellation of type-I seesaw. Embeddings of this mechnism in supersymmetric as well as non-supersymmetric SO(10) with low or intermediate masses of $W_R$ or $Z_R$ bosons are discussed. We also discuss how this cancellation criteria has led to a new mechanism of type-II seesaw dominance which permits $U(1)_{B-L}$ breaking scale much smaller than the left-handed triplet mass. Out of a number of new observable predictions, the most visible ones are the dominant contribution to LFV decays and neutrinoless double beta decay mediated by light sterile neutrinos in the $W_L-W_L$ channel. These seesaw dominance mechanisms are applicable in the extensions of the SM and high, intermediate, or low scale left-right gauge theories with or without their SO(10) origin. Other recent works on the applications of this mechanism covering dark matter and leptogenesis are noted..Comment: 66 pages pdfLatex, 9 figures; Review Artile on Neutrino Physics, Seesaw Mechanisms, and Beyond SM Physics Including GUT

High scale perturbative gauge coupling in R-parity conserving SUSY SO(10) with longer proton lifetime

It is well known that in single step breaking of R-parity conserving SUSY SO(10) that needs the Higgs representations $126+\bar 126$ the GUT-gauge coupling violates the perturbative constraint at mass scales few times larger than the GUT scale. Therefore, if the SO(10) gauge coupling is to remain perturbative up the Planck scale(=2x10^{18} GeV), the scale $M_U$ of GUT symmetry breaking is to be bounded from below. The bound depends upon specific Higgs representations used for SO(10) symmetry breaking but, as we find, can not be lower than $1.5x10^{17}$ GeV. In order to obtain such high unification scale we propose a two-step SO(10) breaking through $SU(2)_LXSU(2)_RXU(1)_{B-L}XSU(3)_C(g_{2L} \neq g_{2R})$ intermediate gauge symmetry. We estimate potential threshold and gravitational corrections to the running of gauge couplings and show that they can make the picture of perturbative GUT- gauge coupling running consistent at least up to the Planck scale. We also show that when $SO(10) \to G_{2213}$ by $210 + 54$, gravitational corrections alone with negligible threshold effects may guarantee such perturbative gauge coupling. The lifetime of the proton is found to increase by nearly 6 orders over the current experimental limit for $p \to e^+\pi^0$. For the proton decay mediated by dim.5 operator a wide range of lifetimes is possible extending from the current experimental limit up to values 2-3 orders longer.Comment: 11 pages epjc LaTex as per specifications of European Physical Journal

Vanishing corrections on the intermediate scale and implications for unification of forces

In two-step breaking of a class of grand unified theories including SO(10),we prove a theorem showing that the scale $M_I$ where the Pati-Salam gauge symmetry with parity breaks down to the standard gauge group,has vanishing corrections due to all sources emerging from higher scales $\mu >M_I$ such as the one-loop and all higher loop effects,the GUT-threshold,gravitational smearing,and string threshold effects. Implications of such a scale for the unification of gauge couplings with small Majorana neutrino masses are discussed.In string inspired SO(10) we show that $M_I \simeq 5\times 10^{12}$,needed for neutrino masses,with the GUT scale $M_U \simeq M_{str}$ can be realized provided certain particle states in the predicted spectum are light.Comment: 21 pages, Late

Sistem Pengambilan Keputusan Kelayakan Peminjaman Kredit dengan Metode Ahp pada Koperasi Kredit Karya Bhakti Kotabumi

Koperasi Kredit Karya Bhakti Kotabumi adalah salah satu Koperasi yang ada di kotabumi. Selama ini Koperasi Kredit Karya Bhakti Kotabumi khususnya dalam menentukan kelayakan peminjaman belum memanfaatkan terknologi komputerisasi dalam mengambil keputusan karna masih menggunakan proses yang manual. Metode yang digunakan dalam penelitian tugas akhir ini adalah metode Waterfall,   alat perancangan sistem yang digunakan adalah mapping chat, data flow diagram, struktur basis database, desain input, desain output, pengkodean, flowchat program, dan struktur menu aplikasi. Hasil dari penelitian ini adalah sebuah program SPK dalam bentuk Microsof Visual Basic 6.0 yang dapat membantu team surpey dalam pengolahan data pemohoan yang akan mengajukan peminjaman kredit. Basis data yang di buat adalah DB-PEMINJAM . Dengan demikian disarankan kepada bagian Team SurpeyKoperasi Kredit Karya Bhakti Kotabumi supaya menggunakan program aplikasi ini agar dalam pengambilan keputusan kelayakan peminjaman kredit dapat lebih efektif dan efisie

New Formulas and Predictions for Running Masses at Higher Scales in MSSM

Including contributions of scale-dependent vacuum expectation values of Higgs scalars, we derive new one-loop formulas analytically for running quark-lepton masses at higher scales in MSSM. Apart from the gauge-coupling dependence being different from earlier formulas, the third-generation- Yukawa-coupling effects are absent in the masses of the first two generations. While predicting the masses and $\tan\beta$ numerically, we also include two-loop effects.Comment: 9 pages Latex.Typos correcte

Intermediate left-right gauge symmetry, unification of couplings and fermion masses in SUSY SO(10)×S4SO(10)\times S_4

If left-right gauge theory occurs as an intermediate symmetry in a GUT then, apart from other advantages, it is possible to obtain the see-saw scale necessary to understand small neutrino masses with Majorana coupling of order unity. Barring threshold or non-renormalizable gravitational effects, or assumed presence of additional light scalar particles of unprescribed origin, all other attempts to achieve manifest one-loop gauge coupling unification in SUSY SO(10) with left-right intermediate symmetry have not been successful so far. Attributing this failure to lack of flavor symmetry in the GUT, we show how the spontaneous symmetry breaking of $SO(10)\times S_4$ leads to such intermediate scale extending over a wide range, $M_R \simeq 5\times 10^{9}$ GeV to $10^{15}$ GeV. All the charged fermion masses are fitted at the see-saw scale, $M_N\simeq M_R \simeq 4 \times 10^{13}$ GeV which is obtained with Majorana coupling $f_0 \simeq 1$. Using a constrained parametrization in which CP-violation originates only from quark sector, besides other predictions made in the neutrino sector, the reactor mixing angle is found to be $\theta_{13} \simeq 3^{\circ} - 5^{\circ}$ which is in the range accessible to ongoing and planned experiments. The leptonic Dirac phase turns out to be $\delta \sim 2.9- 3.1$ radians with Jarlskog invariant $J \sim 2.95 \times 10^{-5} - 10^{-3}$.Comment: Minor clarification and few references added to match the published versio

Precision and uncertainties in mass scale predictions in SUSY SO(10) with SU(2)_L x SU(2)_R x U(1)_{B-L} x SU(3)_C intermediate breaking

In a class of SUSY SO(10) with $SU(2)_L x SU(2)_R x U(1)_{B-L} x SU(3)_C$ $(g_{2L}\neq g_{2R})$ intermediate gauge symmetry, we observe that the prediction on the unification mass $(M_U)$ is unaffected by Planck-scale-induced gravitational and intermediate-scale-threshold effects, although the intermediate scale $(M_I)$ itself is subject to such corrections. In particular, without invoking the presence of additional lighter scalar degrees of freedom but including plausible and reasonable threshold effects, we find that interesting solutions for neutrino physics corresponding to $M_I\simeq 10^{10}-10^{13}$ GeV and $M_U\simeq (5-6) x 10^{17}$ GeV are permitted in the minimal models. Possibilities of low-mass right-handed gauge bosons corresponding to $M_I\simeq 1-10$ TeV consistent with the CERN-LEP data are pointed out in a number of models when threshold effects are included using effective mass parameters.Comment: 12 pages including 7 tables (Typos corrected as per the published version

Standard Coupling Unification in SO(10), Hybrid Seesaw Neutrino Mass and Leptogenesis, Dark Matter, and Proton Lifetime Predictions

We discuss gauge coupling unification of the SM descending directly from SO(10) while providing solutions to the three outstanding problems: neutrino masses, dark matter, and the baryon asymmetry of the universe. Conservation of matter parity as gauged discrete symmetry in the model calls for high-scale spontaneous symmetry breaking through ${126}_H$ Higgs representation. This naturally leads to the hybrid seesaw formula for neutrino masses mediated by heavy scalar triplet and right-handed neutrinos. The seesaw formula predicts two distinct patterns of RH$\nu$ masses, one hierarchical and another not so hierarchical (or compact) when fitted with the neutrino oscillation data. Predictions of the baryon asymmetry via leptogenesis are investigated through the decays of both the patterns of RH$\nu$ masses. A complete flavor analysis has been carried out to compute CP-asymmetries and solutions to Boltzmann equations have been utilized to predict the baryon asymmetry. The additional contribution to vertex correction mediated by the heavy left-handed triplet scalar is noted to contribute as dominantly as other Feynman diagrams. We have found successful predictions of the baryon asymmetry for both the patterns of RH$\nu$ masses. The triplet fermionic dark matter at the TeV scale carrying even matter parity is naturally embedded into the non-standard fermionic representation ${45}_F$ of SO(10). In addition to the triplet scalar and the triplet fermion, the model needs a nonstandard color octet fermion of mass $\sim 10^7$ GeV to achieve precision gauge coupling unification. Threshold corrections due to superheavy components of ${126}_H$ and other representations are estimated and found to be substantial. It is noted that the proton life time predicted by the model is accessible to the ongoing and planned experiments over a wide range of parameter space.Comment: 58 pages PDFLATEX, 19 Figures, Revised as suggested by JHEP Revie

New Formulas and Predictions for Running Fermion Masses at Higher Scales in SM, 2HDM, and MSSM

Including contributions of scale-dependent vacuum expectation values, we derive new analytic formulas and obtain substantially different numerical predictions for the running masses of quarks and charged-leptons at higher scales in the SM, 2HDM and MSSM. These formulas exhibit significantly different behaviours with respect to their dependence on gauge and Yukawa couplings than those derived earlier. At one-loop level the masses of the first two generations are found to be independent of Yukawa couplings of the third generation in all the three effective theories in the small mixing limit. Analytic formulas are also obtained for running $\tan\beta(\mu)$ in 2HDM and MSSM. Other numerical analyses include study of the third generation masses at high scales as functions of low-energy values of $\tan\beta$ and SUSY scale $M_S=M_Z-10^4$ GeV.Comment: 42 pages RevTeX, including 16 figures. Typos corrected and one reference adde