Prospects for measuring ttˉt\bar{t} production cross-section at s=10\sqrt{s}=10 TeV using the likelihood method with the ATLAS detector

Due to the large $t\bar{t}$ production cross-section at the LHC energies, the ATLAS experiment is expected to have enough statistics to measure $t\bar{t}$ cross-section even at initial luminosities. Recent studies performed in ATLAS on the development of $t\bar{t}$ cross-section measurements in the lepton+jets channel at $\sqrt{s}$=10 TeV using the likelihood method will be discussed. The expected statistical and systematic uncertainties for the cross-section measurement using the likelihood method are evaluated for an integrated luminosity of 50 pb$^{-1}$ of Monte Carlo (MC) simulated data. Measurements with data that will be collected in the first year of the LHC operation are emphasized.Comment: To be published in the proceedings of DPF-2009, Detroit, MI, July 2009, eConf C09072

Search for the Higgs boson in the H → WW →ℓ νjj decay channel in pp collisions at s{\sqrt{{s}}}: 7TeV with the ATLAS detector

A search for a Higgs boson has been performed in the H→WW→ℓνjj channel using 1.04 fb − 1 of pp collision data at $\sqrt{s} = 7~{\rm TeV}$ recorded with the ATLAS detector at the Large Hadron Collider. No significant excess of events is observed over the expected Standard Model (SM) background and limits on the Higgs boson production cross-section are derived for a Higgs boson mass in the range 240GeV < m H < 600GeV. The best sensitivity is obtained for m H = 400GeV, where the 95% confidence level upper bound on the cross-section for H→WW production is 3.1 pb, or 2.7 times the Standard Model predictio

SEARCH FOR THE STANDARD MODEL HIGGS BOSON PRODUCTION AND DECAY TO W BOSON PAIRS USING THE LEPTON + MET + JETS CHANNEL USING 4.7 fb−1fb^{-1} OF DATA RECORDED BY THE ATLAS DETECTOR AT s=\sqrt{s} = 7 TEV PROTON-PROTON COLLISION

A search for the Standard Model Higgs boson decaying to two W bosons with the subsequent decay to a final state containing one lepton, one neutrino, and two (or three) jets (H\rightarrow WW^{*}\rightarrow\ell\nujj where $\ell$ stands for electron or muon) is presented using 4.7~fb$^{-1}$ of data recorded by the ATLAS detector in 2011at center of mass energy $\sqrt{s} =$ 7~TeV. No significant excess is observed over the expected Standard Model background.Limits on the Higgs production cross section are derived for masses between \mH = 300 GeV and \mH = 600 GeV. For a Higgsboson mass \mH = 400~GeV, the 95\% confidence level upper bound on the cross-section for Higgs boson production by gluon fusion times thebranching ratio for $H\rightarrow WW^{*}$ is 2.2 pb, or approximately 1.9 times the Standard Model prediction

PREVALENCE OF AEROBIC BACTERIA CAUSING WOUND INFECTION IN PATIENTS WITH FILARIAL ELEPHANTIASIS IN A TERTIARY CARE HOSPITAL OF KOLKATA, INDIA

Lymphatic filariasis, thought to be a neglected tropical disease (NTD) globally, is caused by microscopic, thread-like nematodes. The present study was conducted to identify the microorganisms in the ulcerative wounds of filarial elephantiasis. A total of 100 samples were collected and studied from the patients attended on Filaria OPD, School of Tropical medicine, Kolkata, India. Staphylococcus aureus (46.67%) was identified as the predominant organism among the different aerobic bacteria present in the ulcer, followed by Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella sp., Enterococcus sp., Escherichia coli and Enterobacter sp

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements