National University of La Plata

About: National University of La Plata is a education organization based out in La Plata, Argentina. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 12993 authors who have published 30013 publications receiving 495118 citations. The organization is also known as: UNLP & Universidad Nacional de La Plata.

Search for supersymmetry using final states with one lepton, jets, and missing transverse momentum with the ATLAS detector in √s=7TeV pp collisions

Abstract: This Letter presents the first search for supersymmetry in final states containing one isolated electron or muon, jets, and missing transverse momentum from sqrt{s} = 7 TeV proton-proton collisions at the LHC. The data were recorded by the ATLAS experiment during 2010 and correspond to a total integrated luminosity of 35 pb-1. No excess above the standard model background expectation is observed. Limits are set on the parameters of the minimal supergravity framework, extending previous limits. For A_0 = 0 GeV, tan beta = 3, mu > 0 and for equal squark and gluino masses, gluino masses below 700 GeV are excluded at 95% confidence level.

Automatic first-breaks picking: New strategies and algorithms

Abstract: We have developed three methods for the automatic pickingoffirstbreaksthatcanbeusedformarine,dynamite,orvibroseisshotrecords:amodifiedCoppens’smethod,anentropy-based method, and a variogram fractal-dimension method.Thetechniquesarebasedonthefactthatthetransitionbetweennoiseandnoiseplussignalcanbeautomaticallyidentified by detecting rapid changes in a certain attribute energy ratio, entropy, or fractal dimension, which we calculate withinmovingwindowsalongtheseismictrace.Theapplication of appropriate edge-preserving smoothing operators to enhancethesetransitionsallowedustodevelopanautomated strategy that can be used to easily signal the precise location ofthefirst-arrivalonset.Furthermore,weproposeamispickcorrectingtechniquetoexploitthebenefitsofthedatapresent in the entire shot record, which allows us to adjust the traceby-trace picks and to discard picks associated with bad or dead traces. As a result, the consistency of the first-break picks is significantly improved. The methods are robust under noisy conditions, computationally efficient, and easy to apply. Results using dynamite and vibroseis field data show that accurate and consistent picks can be obtained in an automated manner even under the presence of correlated noise, badtraces,pulsechanges,andindistinctfirstbreaks.