Prafulla Kumar Behera

Bio: Prafulla Kumar Behera is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Large Hadron Collider & Branching fraction. The author has an hindex of 109, co-authored 1204 publications receiving 65248 citations. Previous affiliations of Prafulla Kumar Behera include CERN & Aomori University.

Search for new neutral Higgs bosons through the H→ZA→ℓ+ℓ−bb¯¯¯ process in pp collisions at √s = 13 TeV

Abstract: This paper reports on a search for an extension to the scalar sector of the standard model, where a new CP-even (odd) boson decays to a Z boson and a lighter CP-odd (even) boson, and the latter further decays to a b quark pair. The Z boson is reconstructed via its decays to electron or muon pairs. The analysed data were recorded in proton-proton collisions at a center-of-mass energy $ \sqrt{s} $ = 13 TeV, collected by the CMS experiment at the LHC during 2016, corresponding to an integrated luminosity of 35.9 fb$^{−1}$. Data and predictions from the standard model are in agreement within the uncertainties. Upper limits at 95% confidence level are set on the production cross section times branching fraction, with masses of the new bosons up to 1000 GeV. The results are interpreted in the context of the two-Higgs-doublet model.[graphic not available: see fulltext]

Search for associated production of dark matter with a Higgs boson decaying to bb or γγ at √s=13 TeV

Abstract: A search for dark matter is performed looking for events with large missing transverse momentum and a Higgs boson decaying either to a pair of bottom quarks or to a pair of photons. The data from proton-proton collisions at a center-of-mass energy of 13TeV, collected in 2015 with the CMS detector at the LHC, correspond to an integrated luminosity of 2.3 fb(-1). Results are interpreted in the context of a Z'-two-Higgs-doublet model, where the gauge symmetry of the standard model is extended by a U(1) Z' group, with a new massive Z' gauge boson, and the Higgs sector is extended with four additional Higgs bosons. In this model, a high-mass resonance Z' decays into a pseudoscalar boson A and a light SM-like scalar Higgs boson, and the A decays to a pair of dark matter particles. No signi fi cant excesses are observed over the background prediction. Combining results from the two decay channels yields exclusion limits in the signal cross section in the m(Z')-m(A) phase space. For example, the observed data exclude the Z' mass range from 600 to 1860 GeV, for Z' coupling strength gZ' = 0: 8, the coupling of A with dark matter particles g(X) = 1, the ratio of the vacuum expectation values tan beta = 1, and m(A) = 300GeV. The results of this analysis are valid for any dark matter particle mass below 100 GeV.

Decomposing transverse momentum balance contributions for quenched jets in PbPb collisions at √sNN = 2.76 TeV

Abstract: Interactions between jets and the quark-gluon plasma produced in heavy ion collisions are studied via the angular distributions of summed charged-particle transverse momenta (pt) with respect to both the leading and subleading jet axes in high-pt dijet events. The contributions of charged particles in different momentum ranges to the overall event pt balance are decomposed into short-range jet peaks and a long-range azimuthal asymmetry in charged-particle pt. The results for PbPb collisions are compared to those in pp collisions using data collected in 2011 and 2013, at collision energy sqrt(s[NN]) = 2.76 TeV with integrated luminosities of 166 inverse microbarns and 5.3 inverse picobarns, respectively, by the CMS experiment at the LHC. Measurements are presented as functions of PbPb collision centrality, charged-particle pt, relative azimuth, and radial distance from the jet axis for balanced and unbalanced dijets.

A Deep Neural Network for Simultaneous Estimation of b Jet Energy and Resolution.

Abstract: We describe a method to obtain point and dispersion estimates for the energies of jets arising from b quarks produced in proton-proton collisions at an energy of s=13TeV at the CERN LHC. The algorithm is trained on a large sample of simulated b jets and validated on data recorded by the CMS detector in 2017 corresponding to an integrated luminosity of 41 fb-1 . A multivariate regression algorithm based on a deep feed-forward neural network employs jet composition and shape information, and the properties of reconstructed secondary vertices associated with the jet. The results of the algorithm are used to improve the sensitivity of analyses that make use of b jets in the final state, such as the observation of Higgs boson decay to bb¯ .

Measurement of the top quark mass with lepton+jets final states using p p collisions at √s=13TeV

Abstract: The mass of the top quark is measured using a sample of $${{\text {t}}\overline{{\text {t}}}}$$ events collected by the CMS detector using proton-proton collisions at $$\sqrt{s}=13$$ $$\,\text {TeV}$$ at the CERN LHC. Events are selected with one isolated muon or electron and at least four jets from data corresponding to an integrated luminosity of 35.9 $$\,\text {fb}^{-1}$$ . For each event the mass is reconstructed from a kinematic fit of the decay products to a $${{\text {t}}\overline{{\text {t}}}}$$ hypothesis. Using the ideogram method, the top quark mass is determined simultaneously with an overall jet energy scale factor (JSF), constrained by the mass of the W boson in $${\text {q}} \overline{{\text {q}}} ^\prime $$ decays. The measurement is calibrated on samples simulated at next-to-leading order matched to a leading-order parton shower. The top quark mass is found to be $$172.25 \pm 0.08\,\text {(stat+JSF)} \pm 0.62\,\text {(syst)} \,\text {GeV} $$ . The dependence of this result on the kinematic properties of the event is studied and compared to predictions of different models of $${{\text {t}}\overline{{\text {t}}}}$$ production, and no indications of a bias in the measurements are observed.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Phd by thesis

Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These