Tata Institute of Fundamental Research

About: Tata Institute of Fundamental Research is a education organization based out in Mumbai, Maharashtra, India. It is known for research contribution in the topics: Magnetization & Large Hadron Collider. The organization has 7786 authors who have published 21742 publications receiving 622368 citations. The organization is also known as: TIFR.

Supersymmetry Parameter Analysis: SPA Convention and Project

Abstract: High-precision analyses of supersymmetry parameters aim at reconstructing the fundamental supersymmetric theory and its breaking mechanism. A well defined theoretical framework is needed when higher-order corrections are included. We propose such a scheme, Supersymmetry Parameter Analysis SPA, based on a consistent set of conventions and input parameters. A repository for computer programs is provided which connect parameters in different schemes and relate the Lagrangian parameters to physical observables at LHC and high energy e+e- linear collider experiments, i.e., masses, mixings, decay widths and production cross sections for supersymmetric particles. In addition, programs for calculating high-precision low energy observables, the density of cold dark matter (CDM) in the universe as well as the cross sections for CDM search experiments are included. The SPA scheme still requires extended efforts on both the theoretical and experimental side before data can be evaluated in the future at the level of the desired precision. We take here an initial step of testing the SPA scheme by applying the techniques involved to a specific supersymmetry reference point.

Phenomenology of the low-energy spectral function in high-T c superconductors

Abstract: We introduce a simple phenomenological form for the self-energy which allows us to extract important information from angle-resolved photoemission data on the high-${T}_{c}$ superconductor ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8}$ for binding energies of order the spectral gap. First, we find a rapid suppression of the single particle scattering rate below ${T}_{c}$ for all doping levels. Second, we find that in the overdoped materials the gap $\ensuremath{\Delta}$ at all k points on the Fermi surface has significant temperature dependence and vanishes near ${T}_{c}.$ In contrast, in the underdoped samples such behavior is found only at k points close to the diagonal. Near $(\ensuremath{\pi},0)$, $\ensuremath{\Delta}$ is essentially $T$ independent in the underdoped samples. The filling-in of the pseudogap with increasing $T$ is described by a broadening proportional to $T\ensuremath{-}{T}_{c},$ which is naturally explained by pairing correlations above ${T}_{c}.$

Time-Resolved Area-Normalized Emission Spectroscopy (TRANES): A Novel Method for Confirming Emission from Two Excited States

Abstract: A model-free method is described for constructing time-resolved area-normalized emission spectra (TRANES) using luminescence decays at all emission wavelengths. An isoemissive point in TRANES indicates that the observed emission from the sample is due to two species only, irrespective of the origin of the two species or the excited-state kinetics. Proof for the existence of an isoemissive point in TRANES is given for various cases involving two emissive species. The isoemissive point in TRANES is qualitatively similar to the isosbestic point in time-resolved absorption spectra (TRAS) in kinetic spectrophotometry involving two species.

The Belle II Physics Book

Abstract: The Belle II detector will provide a major step forward in precision heavy flavor physics, quarkonium and exotic states, searches for dark sectors, and many other areas. The sensitivity to a large number of key observables can be improved by about an order of magnitude compared to the current measurements, and up to two orders in very clean search measurements. This increase in statistical precision arises not only due to the increased luminosity, but also from improved detector efficiency and precision for many channels. Many of the most interesting observables tend to have very small theoretical uncertainties that will therefore not limit the physics reach. This book has presented many new ideas for measurements, both to elucidate the nature of current anomalies seen in flavor, and to search for new phenomena in a plethora of observables that will become accessible with the Belle II dataset. The simulation used for the studiesinthis book was state ofthe artat the time, though weare learning a lot more about the experiment during the commissioning period. The detector is in operation, and working spectacularly well.