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We report on a novel application of computer vision techniques to extract beyond the Standard Model (BSM) parameters directly from high energy physics (HEP) flavor data. We develop a method of transforming angular and kinematic distributions into "quasi-images" that can be used to train a convolutional neural network to perform regression tasks, similar to fitting. This contrasts with the usual classification functions performed using ML/AI in HEP. As a proof-of-concept, we train a 34-layer Residual Neural Network to regress on these images and determine the Wilson Coefficient $C_{9}$ in MC (Monte Carlo) simulations of $B \rightarrow K^{*}\mu^{+}\mu^{-}$ decays. The technique described here can be generalized and may find applicability across various HEP experiments and elsewhere.

Within the widely used EvtGen framework, we have added a new event generator model for $B\to K^* \ell^+ \ell^-$ with improved standard model (SM) decay amplitudes and possible BSM physics contributions, which are implemented in the operator product expansion in terms of Wilson coefficients. This event generator can then be used to investigate the experimental sensitivity to the most general BSM signal resulting from dimension-six operators. We describe the advantages and potential of the newly developed `Sibidanov Physics Generator' in improving experimental sensitivity of searches for lepton non-universal BSM physics and clarifying signatures. The new generator can properly simulate BSM scenarios, interference between SM and BSM amplitudes, and correlations between different BSM observables as well as acceptance bias. We show that exploiting such correlations substantially improves experimental sensitivity. As a demonstration of the utility of the MC generator, we examine the prospects for improved measurements of lepton non-universality in angular distributions for $B \to K^* \ell \ell$ decays from the expected 50 ab$^{-1}$ data set of the Belle II experiment, using a four-dimensional unbinned maximum likelihood fit. We describe promising experimental signatures and correlations between observables. The use of lepton-universality violating $\Delta$-observables significantly reduce uncertainties in the SM expectations due to QCD and resonance effects, are ideally suited for Belle II with the large data sets expected in the next decade. Our simulation studies also show that Belle II should have excellent sensitivity to BSM physics in the Wilson coefficients $C_7$ and $C_7'$, which appears at low $q^2$ in the di-electron channel., Comment: A contribution to Snowmass 2021 but not included in the final proceedings, to be submitted to JHEP

The seamless forecast approach of subseasonal to seasonal scale variability has been succeeding in the forecast of multiple meteorological scales in a uniform framework. In this paradigm, it is hypothesized that reduction in initial error in dynamical forecast would help to reduce forecast error in extended lead-time up to 2-3 weeks. This is tested in a version of operational extended range forecasts based on Climate Forecast System version 2 (CFSv2) developed at Indian Institute of Tropical Meteorology (IITM), Pune. Forecast skills are assessed to understand the role of initial errors on the prediction skill for MJO. A set of lowest and highest initial day error (LIDE & HIDE) cases are defined and the error-growth for these categories are analysed for the strong MJO events during May to September (MJJAS). The MJO forecast initial errors are categorized and defined using the well-known multivariate MJO index introduced by Wheeler &Hendon (2004). The probability distribution of bivariate RMSE and error growth evolution (first order difference of index error for each successive lead days) with respect to extended range lead-time are used as metrics in this analysis. The result showed that initial error is not showing any influence in the skill of model after a lead time of 7-10 days and the error growth remains the same for both set of errors. A rapid error growth evolution of same order is seen for both the classified cases. Further the physical attribution of these errors is studied and found that the errors originate from the events with initial phase in Western Pacific and Indian Ocean. The spatial distribution of OLR and the zonal winds also confirms the same. The study emphasises the importance of better representation of MJO phases especially over Indian ocean in the model to improve the MJO prediction rather than focusing primarily on the initial condition, Comment: 27 pages, 9 figures

Thin films and heterostructures of hexagonal manganites as promising multiferroic materials have attracted a considerable interest recently. We report structural transformations of high quality epitaxial h-TMO/YSZ(111) films, analyzed by means of various characterization techniques. A phase transition from P63mc to P63mcm structure at TC~800 K was observed by temperature dependent Raman spectroscopy and optical ellipsometry. The latter probing directly electronic system, indicates its modification at the structural phase transition likely due to charge transfer from oxygen to Mn. In situ transmission electron microscopy (TEM) of the lamella samples displayed an irreversible P63mc-P63mcm transformation and vanishing of ferroelectric domains already at 410 K. After the temperature cycling (300K-1300K-300K) the room temperature TEM of h-TMO films revealed an inhomogeneous microstructure, containing ferroelectric and paraelectric nanodomains with P63mc and P63mcm structure, respectively. We point out a strong influence of stress relaxation, induced by temperature and by constrained sample geometry onto the structure and ferroelectricity in strain-stabilized h-TMO thin films., Comment: 24 pages, 10 figures

We report magneto-dielectric properties of partially B-site ordered monoclinic Tb2CoMnO6 double perovskite thin film epitaxially grown by metalorganic aerosol deposition technique. Transmission electron microscopy and electron energy loss spectroscopy mapping shows the presence and distribution of both Co2+ and Co3+ ions in the film, evidencing a partial B-site disorder, which was further confirmed by the observation of reduced saturation magnetization at low temperatures. The ferromagnetic Curie temperature, TC=110 K, is slightly higher as compared to the bulk value (100 K) probably due to an in plane tensile strain. Remarkably, a short range ordering of spins at T*~190 K>>TC was established and assigned to the B-site disorder in the film. Two different dielectric relaxation peaks have been observed; they merge at the same temperature T* of short range spin correlations. Moreover, an unexpected high temperature dipolar relaxor-glass-like transition at T~T* was observed, at which a coupling to short range magnetic correlations results in a 4% magneto-dielectric coupling., Comment: 19 pages, 6 figures

We report on the synthesis of carbon nanotubes on quasicrystalline alloys. Aligned multiwalled carbon nanotubes (MWNTs) on the conducting faces of decagonal quasicrystals were synthesized using floating catalyst chemical vapor deposition. The alignment of the nanotubes was found perpendicular to the decagonal faces of the quasicrystals. A comparison between the growth and tube quality has also been made between tubes grown on various quasicrystalline and SiO2 substrates. While a significant MWNT growth was observed on decagonal quasicrystalline substrate, there was no significant growth observed on icosahedral quasicrystalline substrate. Raman spectroscopy and high resolution transmission electron microscopy (HRTEM) results show high crystalline nature of the nanotubes. Presence of continuous iron filled core in the nanotubes grown on these substrates was also observed, which is typically not seen in MWNTs grown using similar process on silicon and/or silicon dioxide substrates. The study has important implications for understanding the growth mechanism of MWNTs on conducting substrates which have potential applications as heat sinks.

A four dimensional description for the trigonal phase is presented. It has been demonstrated that it is possible to model one dimensional quasiperiodic structure with trigonal symmetry apart from recovering the Miller-Bravais scheme for the description of hexagonal phases. A similar discussion on the two classes of decagonal phases having 10/m and 105 symmetries will be given. The distinction in the six dimensional models of the two classes of solids has been pointed out. The zone rules for all the cases have been formulated. The critical comparison for the structural description of trigonal, decagonal and related phases in terms of higher dimension is made. The unification achieved in the higher dimensional structural models of various phases has been emphasized. The importance of such models for the study of structural phase transformation has been indicated., Comment: 27 pages having a comprehensive table

The Kolmogorov-Johnson-Mehl-Avrami model for isothermal transformation kinetics is universal under specific assumptions. However, the experimental Avrami exponent deviates from the universal value. In this context, we study the effect of transient heterogeneous nucleation on the Avrami exponent for bulk materials and also for transformations leading to nanostructured materials. All transformations are assumed to be polymorphic. A discrete version of the KJMA model is modified for this purpose. Scaling relations for transformations under different conditions are reported., Comment: 19 pages, 6 figures Accepted for publication in Journal of Non-Crystalline Solids