Neutrino Masses and Mixings in a Minimal SO(10) Model

We consider a minimal formulation of SO(10) Grand Unified Theory wherein all the fermion masses arise from Yukawa couplings involving one 126 and one 10 of Higgs multiplets. It has recently been recognized that such theories can explain, via the type-II seesaw mechanism, the large \nu_\mu - \nu_\tau mixing as a consequence of b-tau unification at the GUT scale. In this picture, however, the CKM phase \delta lies preferentially in the second quadrant, in contradiction with experimental measurements. We revisit this minimal model and show that the conventional type-I seesaw mechanism generates phenomenologically viable neutrino masses and mixings, while being consistent with CKM CP violation. We also present improved fits in the type-II seesaw scenario and suggest fully consistent fits in a mixed scenario.Comment: 27 pages, 13 eps figures, revtex4; references added, some minor correction

Dihedral Families of Quarks, Leptons and Higgs Bosons

We consider finite groups of small order for family symmetry. It is found that the binary dihedral group Q_6, along with the assumption that the Higgs sector is of type II, predicts mass matrix of a nearest neighbor interaction type for quarks and leptons. We present a supersymmetric model based on Q_6 with spontaneously induced CP phases. The quark sector contains 8 real parameters with one independent phase to describe the quark masses and their mixing. Predictions in the |V_{ub}|-bar{eta}, |V_{ub}|-sin 2 beta(phi_1) and |V_{ub}|-|V_{td}/V_{ts}| planes are given. The lepton sector contains also 9 parameters. A normal as well as an inverted spectrum of neutrino masses is possible, and we compute V_{e3}. We find that |V_{e3}|^2 > 10^{-4} in the case of a normal spectrum, and |V_{e3}|^2 >8 10^{-4} in the case of an inverted spectrum. It is also found that Q_6 symmetry forbids all Baryon number violating terms of d=4, and the contributions to EDMs from the A terms vanish in this model.Comment: 27 pages, 8 figure

Supersymmetry, local horizontal unification, and a solution to the flavor puzzle

Supersymmetric gauge models with local horizontal symmetries are known to generate large flavor changing neutral current effects induced by supersymmetry breaking D-terms. We show how the presence of a U(1) gauge symmetry solves this problem. We then construct a realistic gauge model with SU(2)_H x U(1)_H as the local horizontal symmetry and suggest that the U(1)_H factor may be identified with the anomalous U(1) induced by string compactification. This model explains the observed hierarchies among the quark masses and mixing angles, accommodates naturally the solar and atmospheric neutrino data, and provides simultaneously a solution to the supersymmetric flavor problem. The model can be excluded if the rare decay \mu --> e \gamma is not observed in the current round of experiments.Comment: 10 pages in RevTe

Natural Gauge Hierarchy in SO(10)

It is shown that a natural gauge hierarchy and doublet-triplet splitting can be achieved in SO(10) using the Dimopoulos-Wilczek mechanism. Artificial cancellations (fine-tuning) and arbitrary forms of the superpotential are avoided, the superpotential being the most general compatible with a symmetry. It is shown by example that the Dimopoulos-Wilczek mechanism can be protected against the effects of higher-dimension operators possibly induced by Planck-scale physics. Natural implementation of the mechanism leads to an automatic Peccei-Quinn symmetry. The same local symmetries that would protect the gauge hierarchy against Planck-scale effects tend to protect the axion also. It is shown how realistic quark and lepton masses might arise in this framework. It is also argued that ``weak suppression'' of proton decay can be implemented more economically than can ``strong suppression'', offering some grounds to hope (in the context of SO(10)) that proton decay could be seen at Superkamiokande.Comment: 26 pages in plain LaTeX, 5 figures available on request, BA-94-0

Mayer-Rokitansky-Kuster-Hauser syndrome with gonadohypoplasia:a rare case report

MRKH (Mayer Rokitansky Kuster Hauser) syndrome is a congenital abnormality seen in one out of 5,000 women characterized by the agenesis of the vagina, cervix, and uterus. It is also associated with kidney, bone and hearing difficulties. The ovaries are present with a normal function similar to that of a healthy reproductive woman’s by producing eggs and female hormones. Chromosomes are the normal 46xx female karyotype. We report this rare syndrome in a 26–year-old female where she had presented with complaints of absence of uterus with the absence of left kidney. She didn’t attain menarchy, secondary sexual characters are well developed. Small right ovarian follicular cyst with a rim of ovarian tissue was observed. She had undergone vaginoplasty

Water-saving Rice Production Technologies in Krishna Western Delta Command of Andhra Pradesh – An Economic Analysis

The economic analysis of water-saving rice production technologies, viz. system of rice intensification (SRI), semi-dry and rotational irrigation vis-à-vis farmers’ practice has been carried out based on the study executed in Modukuru pilot area of Guntur district of Andhra Pradesh. Among the three water-saving rice production technologies analyzed, the total cost of cultivation has been recorded highest in SRI (Rs 58645/ha), followed by rotational (Rs 47140/ha) and semi-dry (Rs 39321/ha). But, the per hectare yield has been found highest in SRI (6.85 t), followed by semi-dry (6.66 t) and rotational (6.2 t), inferring that all the three technologies have recorded higher yields over farmers’ practice of 5.5 t/ha. However, the net returns and B-C ratio are maximum in semi-dry (Rs 43,484/ha; 1.11), followed by rotational (Rs 30,085; 0.64) and SRI (Rs 26,466/ha; 0.45) methods. Similarly, the water-use efficiency has been found highest in SRI (8.53 kg/ ha-mm), followed by semi-dry (8.02 kg/ha-mm) and rotational (7.33 kg/ ha-mm) methods, while the water-use efficiency benefit (Rs/ha-mm) has been recorded maximum in semi-dry (52.39), followed by SRI (42.08) and rotational (35.56) methods. With the initiation of Andhra Pradesh Water Management Project, Bapatla, the area under semi-dry rice cultivation has been found increasing over a period of four years, from 0.6 ha in 2004-2005 to 22 ha in 2007 -2008.Agricultural and Food Policy,

Design and Fabrication of Little gourd cutter

Plywood base was used as a platform to place the entire equipment. Stainless steel blade was attached to the shaft of motor of 240V which acts as cutting unit. Stainless steel cylinder with supporting iron rod is used for feeding little gourds. A rectangular frame made up of metallic stands was used as main frame and supporting main units. A collection tray made up of metal sheet was used for collection of slices. Moisture content of little gourds was 85%. The dimensions of little gourds were measured using digital Vernier callipers and weight of each little gourd was measured using electronic weighing balance. Average length and diameter of little gourds were found to be 17.93mm and 18.88mm respectively. The other parameters like Sphericity, roundness, cylindrical and elliptical were found to be 0.14cm, 3.73cm2, 19.87cm3 and 0.89cm-3 respectively. Average weight of the little gourds were found to be 16.5g. The surface area and bulk density of little gourds were found to be 180.6 sq.cm and 500 kg/m3. Performance evaluation of little gourd cutter was performed where slicing operation was performed at different motor speeds and voltages. High motor speed with voltage of 240V gave slices of 0.75mm which were suitable for household consumption

Solar neutrinos and grand unification

We consider the Grand Unification (GU) scenario for neutrino masses which is based on the see-saw mechanism with the mass of the heaviest right handed (RH) neutrino at the GU-scale: $M_3 \sim \Lambda_{GU}$, and on the quark-lepton symmetry for fermions from the third generation. The scenario predicts for the light neutrinos: $m_3 \sim (2 - 4) \cdot 10^{-3}$ eV and $m_2 \sim (0.3 - 3) \cdot 10^{-5}$ eV (in the case of a linear mass hierarchy of the RH neutrinos or/and in presence of the Planck scale suppressed non-renormalizable operators). It also predicts large $\nu_e - \nu_{\mu}$ mixing: $~\sin^2 2\theta_{e\mu} \stackrel{_>}{_\sim} 0.2$. In this scenario the solar neutrinos ($\nu_{\odot}$) undergo both the \nue $\to$ \nutau resonance conversion in the Sun and substantial \nue $\to$ \numu vacuum oscillations on the way from the Sun to the Earth. The interplay of both effects enlarges the range of neutrino parameters which solve the $\nu_{\odot}$-problem. In particular, $\nu_e - \nu_{\tau}$ mixing angle can be as small as the corresponding quark mixing: $\sin^2 2\theta_{e\tau} \geq (2~-~5) \cdot 10^{-4}$. The scenario predicts peculiar (oscillatory) distortion of the boron neutrino energy spectrum and seasonal variations of signals. Manifestations of these effects in the Super-Kamiokande and SNO experiments are studied.Comment: 36 pages, LaTeX, includes 14 figures, revised and expande

Universal Seesaw Mass Matrix Model with an S_3 Symmetry

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 \bar{f}_L m_L F_R +\bar{F}_L m_R f_R + \bar{F}_L M_F F_R + h.c. and the form of M_F is democratic on the bases on which m_L and m_R are diagonal, the following model is discussed: The mass terms M_F are invariant under the permutation symmetry S_3, and the mass terms m_L and m_R are generated by breaking the S_3 symmetry spontaneously. The model leads to an interesting relation for the charged lepton masses.Comment: 8 pages + 1 table, latex, no figures, references adde