Zee-model predictions for lepton flavor violation

The Zee model provides a simple model for one-loop Majorana neutrino masses. The new scalars can furthermore explain the long-standing deviation in the muon's magnetic moment and the recent CDF measurement of the $W$-boson mass. Together, these observations yield predictions for lepton flavor violating processes that are almost entirely testable in the near future. The remaining parameter space makes testable predictions for neutrino masses.Comment: 6 pages, 4 figures, Updated references, matches published versio

WW boson mass shift, dark matter and (g−2)ℓ(g-2)_\ell in ScotoZee model

We present a singly charged scalar extension of the Scotogenic model, ScotoZee, which resolves the recently reported deviations in $W$ boson mass as well as lepton $g-2$. The model admits a scalar or a fermionic dark matter while realizing naturally small radiative neutrino masses. The mass splitting of $\sim 100$ GeV, required by the shift in $W$ boson mass, among the inert doublets fields can be evaded by its mixing with the singlet scalar, which is also key to resolving $(g-2)_\ell$ anomaly within $1\sigma$. We establish the consistency of this framework with dark matter relic abundance while satisfying constraints from charged lepton flavor violation, direct detection as well as collider bounds. The model gives predictions for the lepton flavor violating $\tau\to\ell\gamma$ processes testable in upcoming experiments.Comment: 4 pages and references, 5 figures, references added, improved LFV analysi

General Approach to Neutrino Mass Mechanisms with Sterile Neutrinos

We present a mathematical framework for constructing the most general neutrino mass matrices that yield the observed spectrum of light active neutrino masses in conjunction with arbitrarily many heavy sterile neutrinos, without the need to assume a hierarchy between Dirac and Majorana mass terms. The seesaw mechanism is a byproduct of the formalism, along with many other possibilities for generating tiny neutrino masses. We comment on phenomenological applications of this approach, in particular deriving a mechanism to address the long-standing $(g-2)_\mu$ anomaly in the context of the left-right symmetric model.Comment: 5 pages and appendices, 2 figure

Neutrinos: A gateway to beyond the standard model

The Standard Model (SM) of particle physics based on the gauge group $SU(3) \otimes SU(2)_L \otimes U(1)_Y$ is very appealing as it describes physics at low energy quite spectacularly. However, it cannot be an ultimate theory of nature as both theoretical and experimental evidence implies new physics at high and low energy scales. For instance, it fails to describe several phenomena such as neutrino masses and mixings, the strong hierarchy in the masses of fermions, dark matter candidates, and the origin of the baryon asymmetry in the universe. Thus, a fundamental framework beyond the standard model (BSM) is needed to resolve the shortcomings of the SM. Constructing such BSM models to tackle these fundamental problems of the SM while being consistent with the existing low-energy data, focusing on explaining the neutrino masses and oscillations, is the primary goal of this dissertation.Several BSM models have been developed in this thesis to resolve the shortcomings of the SM, using applied group theory and quantum field theory. Furthermore, each model detailed out has its unique characteristics and several phenomenological consequences. Various neutrino mass models, in particular, are proposed to shed light on the unresolved puzzles of fundamental physics. Neutrinos can play an important role in particle physics, cosmology, and astrophysics: their properties have significant consequences on large-scale cosmological structures and the baryon asymmetry of the universe. On the other hand, cosmology put essential constraints on the neutrino mass making as a probe to test the proposed theories beyond the SM. This dissertation cast light on BSM physics with various neutrino mass models ranging from MeV scale to TeV scale new physics that can be tested at future colliders and neutrino experiments. For instance, it discusses the model of radiative neutrino masses at electroweak scale which also resolves anomalies reported in $B$-meson decays, $R_{D^{(\star)}}$ and $R_{K^{(\star)}}$, as well as in muon $g-2$ measurement, $\Delta a_\mu$. Moreover, models of radiative Majorana neutrino masses that require new scalars can also generate observable neutrino non-standard interactions (NSI) with the matter

Response of Stubble Shaving Times on Ratoon Yield of Different Sugarcane Genotypes

Ratooning is common practice done in sugarcane with purpose of reducing the total cost of cultivation and early cane maturity. More than 35% of sugarcane productivity is lost due to improper attention of the farmers towards ratoons. Majority of farmers reported that the ratoonability wasn’t good when harvested in December-January. This experiment was carried out to find the appropriate ratoon shaving time with response to different varieties in sugarcane ratoon crop in the year 2018/19 at national sugarcane research project, Jitpur, Bara. The experiment was conducted in split plot design with four levels of cane genotypes as Co – 0238, CoLk – 94184, Co – 0233 and CoS – 07250 as the main plot factor while four harvesting dates as sub plot factor with three replications. Observations of a number of millable canes, single cane weight, plant height and single cane diameter were recorded, tabulated and analyzed in R-studio. Ratoon stubble shaving in the month of November had the highest number of millable canes (88079/ha) which wasn’t significantly different from the stubble shaving in the month of December, January. Likewise, highest cane yield (60.04 mt/ha), single cane weight (0.757 kg), cane diameter (2.11 cm), plant height (1.82 m) were found in early stubble shaving dates. Cane Yield and various yield parameter shows better performance in early ratoon shaving periods i.e. from November to January than late ratoon shaving dates

Minimal model for the WW-boson mass, (g−2)μ(g−2)μ​, h→μ+μ−h→μ+μ− and quark-mixing-matrix unitarity

The SU(2)L triplet scalar with hypercharge Y=0 predicts a positive definite shift in the W mass, with respect to the Standard Model prediction, if it acquires a vacuum expectation value. As this new field cannot couple directly to Standard Model fermions (on its own), it has no significant impact on other low-energy precision observables and is weakly constrained by collider searches. In fact, the multilepton anomalies at the LHC even point toward new scalars that decay dominantly to W bosons, as the neutral component of the triplet naturally does. In this article, we show that with a minimal extension of the scalar triplet model by a heavy vectorlike lepton, being either (I) an SU(2)L doublet with Y=−1/2 or (II) an SU(2)L triplet with Y=−1, couplings of the triplet to Standard Model leptons are possible. This minimal extension can then provide, in addition to the desired positive shift in the W mass, a chirally enhanced contribution to (g−2)μ. In addition, versions (I) and (II) can improve on Z→μ+μ− and alleviate the tension in first-row Cabibbo-Kobayashi-Maskawa unitarity (known as the Cabibbo angle anomaly), respectively. Finally, both options, in general, predict sizable changes of h→μ+μ−, i.e., much larger than most other (g−2)μ explanations where only O(%) effects are expected, making this channel a smoking gun signature of our model

Neutrino mass models at μ\muTRISTAN

We study the prospects of probing neutrino mass models at the newly proposed antimuon collider $\mu$TRISTAN, involving $\mu^+e^-$ scattering at $\sqrt{s}= 346$ GeV and $\mu^+\mu^+$ scattering at $\sqrt{s}= 2$ TeV. We show that $\mu$TRISTAN is uniquely sensitive to leptophilic neutral and doubly-charged scalars naturally occurring in various neutrino mass models, such as Zee, Zee-Babu, cocktail, and type-II seesaw models, over a wide range of mass and coupling values, well beyond the current experimental constraints. It also allows for the possibility to correlate the collider signals with neutrino mixing parameters and charged lepton flavor violating observables.Comment: 8 pages and references, 5 figure