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Adragna, P.

Publications and source records attributed to Adragna, P..

At least 91 records · Page 5
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DOE OSTI2012

Search for second generation scalar leptoquarks in pp collisions at $\sqrt{s}=7~\mbox{TeV}$ with the ATLAS detector

The results of a search for the production of second generation scalar leptoquarks are presented for final states consisting of either two muons and at least two jets or a muon plus missing transverse momentum and at least two jets. A total of 1.03 fb -1 integrated luminosity of protonproton collision data produced by the Large Hadron Collider at √s = 7 TeV and recorded by the ATLAS detector is used for the search. The event yields in the signal regions are found to be consistent with the Standard Model background expectations. The production of second generation leptoquarks is excluded for a leptoquark mass m LQ < 594 (685) GeV at 95 % confidence level, for a branching ratio of 0.5 (1.0) for leptoquark decay to a muon and a quark.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2012

A search for $t\bar{t}$ resonances with the ATLAS detector in 2.05 fb -1 of proton-proton collisions at $\sqrt{s} = 7~\mathrm{TeV}$

A search for top quark pair resonances in final states containing at least one electron or muon has been performed with the ATLAS experiment at the CERN Large Hadron Collider. The search uses a data sample corresponding to an integrated luminosity of 2.05 fb -1 , which was recorded in 2011 at a proton-proton centre-of-mass energy of 7 TeV. No evidence for a resonance is found and limits are set on the production cross-section times branching ratio to $t\overline{t}$ for narrow and wide resonances. For narrow Z' bosons, the observed 95 % Bayesian credibility level limits range from 9.3 pb to 0.95 pb for masses in the range of m Z' =500 GeV to mZ' =1300 GeV. The corresponding excluded mass region for a leptophobic topcolour Z' boson (Kaluza-Klein gluon excitation in the Randall-Sundrum model) is m Z' <880 GeV (m gKK <1130 GeV).

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2012

Measurement of τ polarization in W→τν decays with the ATLAS detector in pp collisions at $\sqrt{s} =7~\mathrm{TeV}$

Here in this paper, a measurement of τ polarization in W→τν decays is presented. It is measured from the energies of the decay products in hadronic τ decays with a single final state charged particle. The data, corresponding to an integrated luminosity of 24 pb -1 , were collected by the ATLAS experiment at the Large Hadron Collider in 2010. The measured value of the τ polarization is P τ = -1.06 ± 0.04 (stat)$+0.05\atop{-0.07}$ (syst), in agreement with the Standard Model prediction, and is consistent with a physically allowed 95 % CL interval [-1,-0.91]. Measurements of τ polarization have not previously been made at hadron colliders.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗