On July 4, 2012 two experiments, working at the CERN Large Hadron Collider, jointly announced a strong evidence of observing a new particle state. The observed particle, approximately 135 times heavier than proton and with a very short life time, could be the elusive Higgs boson which the high energy physicists have been earnestly looking for during the past 25 years. This will close one of the puzzles of the Standard Model of particle physics. More recent data have demonstrated some of the intrinsic properties of this new particle. The search involved a consolidated effort from thousands of physicists from all over the world over two decades. The challenges in this search and Indian effort in this process will be discussed.
06/05/2013 at 4:00 pm
Prof. Prasanta Tripathy, IIT Chennai
HEP Seminar
Lecture Hall Block A, Institute of Physics
Document Date:
Attractor Mechanism in String Theory and Gauged Supergravity
We determine the strong coupling constant alpha_s from the au; hadronic width using renormalization group summed expansion of the QCD Adlerfunction. The main theoretical uncertainty in the extraction of alpha_s is due tothe way in which renormalization group invariance is implemented and the yetuncalculated higher order terms in the QCD perturbative series. We show that new expansion exhibitsnice renormalization group improvement and the behaviour of the series is similar tostandard CIPT expansion. We further study the convergence properties of this expansion improved byBorel transformation and the analytical continuation in the Borel plane. We find that thenew, non-power expansions for different conformal mappings have remarkable convergence. Finally weprovide the value of strong coupling alpha_s using the new, non-power perturbative expansionswhich is alpha_s(M_ au ) = 0.3189+0.0145−0.0115, which translates to alpha_s(M_Z ) =0.1184+0.0018−0.0015.
17/04/2013 at 4:00 pm
Mr. Suprabh Prakash, IIT, Bombay
HEP Seminar
Lecture Hall Block A, Institute of Physics
Document Date:
Exploring 3-flavor effects with present and next generation long baseline superbeam neutrino experiments
Exploring 3-flavor effects with present and next generation long baseline superbeam neutrino experiments
Abstract
Various neutrino experiments till now, have explored the dominant 2-flavoreffects in neutrino oscillations.They have been very successful in constraining some of the oscillationparameters. The next step in thisfield is building experiments which will probe the sub-dominant 3-flavoreffects and the related oscillationparameters. This is a difficult task. In this talk, I will start with abrief discussion of the physics of neutrinooscillations. This will be followed by a discussion of the present statusof the neutrino oscillation parameters.Finally, I will present my work which is phenomenology of present and nextgeneration long baselinesuperbeam neutrino experiments.
