Measurements of top quark properties at the Tevatron collider

The discovery of the top quark in 1995 opened a whole new sector of investigation of the Standard Model; today top quark physics remains a key priority of the Tevatron program. Some of the measurements of top quark properties, for example its mass, will be a long-standing legacy. The recent evidence of an anomalously large charge asymmetry in top quark events suggests that new physics could couple preferably with top quarks. I will summarize this long chapter of particle physics history and discuss the road the top quark is highlighting for the LHC program.Comment: Presented at the 2011 Rencontres de Moriond EW, La Thuile, Aosta Valley, Italy, 13-20 Mar 201

Top physics at the Tevatron Collider

The top quark has been discovered in 1995 at the CDF and DO experiments located in the Tevatron ring at the Fermilab laboratory. After more than a decade the Tevatron collider, with its center-of-mass energy collisions of 1.96 TeV, is still the only machine capable of producing such exceptionally heavy particle. Here I present a selection of the most recent CDF and DO measurements performed analyzing ~ 1 fb-1 of integrated luminosity.Comment: 5 pages, 4 figure, Proceedings 19th Conference on High Energy Physics (IFAE 2007), Naples, Italy, April 11-13, 200

Measurement of the top quark properties at the Tevatron and the LHC

Almost two decades after its discovery at Fermilab's Tevatron collider experiments, the top quark is still under the spotlight due to its connections to some of the most interesting puzzles in the Standard Model. The Tevatron has been shut down two years ago, yet some interesting results are coming out of the CDF and D0 collaborations. The LHC collider at CERN produced two orders of magnitude more top quarks than Tevatron's, thus giving birth to a new era for top quark physics. While the LHC is also down at the time of this writing, many top quark physics results are being extracted out of the 7\,TeV and 8\,TeV proton proton collisions by the ATLAS and CMS collaborations, and many more are expected to appear before the LHC will be turned on again sometime in 2015. These proceedings cover a selection of recent results produced by the Tevatron and LHC experiments.Comment: PIC 2013 conference proceedings, to appear in International Journal of Modern Physic

The search for the Standard-Model Higgs boson at hadron colliders

This paper summarises the results of the search for the Standard-Model Higgs boson at the Tevatron and LHC experiments. With their everincreasing integrated data samples, the CDF and D0 experiments have now ruled out the possibility for the existence of the Higgs boson with mass in the 163–166GeV/c2 window. The excluded region is supposed to grow over time as more data is collected and experimentalists refine their searches. At the LHC, data taking at 7TeV center-of-mass energy has recently started and up to 1 fb−1 is expected to be collected by the end of 2011, before a shutdown will halt operations for about a year. Sensitivity projections for the ATLAS and CMS Collaborations are discussed

Direct constraints on the top-Higgs coupling from the 8 TeV LHC data

The LHC experiments have analyzed the 7 and 8 TeV LHC data in the main Higgs production and decay modes. Current analyses only loosely constrain an anomalous top-Higgs coupling in a direct way. In order to strongly constrain this coupling, the Higgs-top associated production is reanalyzed. Thanks to the strong destructive interference in the t-channel for standard model couplings, this process can be very sensitive to both the magnitude and the sign of a non-standard top-Higgs coupling. We project the sensitivity to anomalous couplings to the integrated luminosity of 50 fb^{-1}, corresponding to the data collected by the ATLAS and CMS experiments in 7 and 8 TeV collisions, as of 2012. We show that the combination of di-photon and multi-lepton signatures, originating from different combinations of the top and Higgs decay modes, can be a potential probe to constrain a large portion of the negative top-Higgs coupling space presently allowed by the ATLAS and CMS global fits.Comment: 21 pages, 4 figures; a few reducible backgrounds included, final results unchanged, to appear in JHE

Quality Testing of Gaseous Helium Pressure Vessels by Acoustic Emission

The resistance of pressure equipment is currently tested, before commissioning or at periodic maintenance, by means of normal pressure tests. Defects occurring inside materials during the execution of these tests or not seen by usual non-destructive techniques can remain as undetected potential sources of failure . The acoustic emission (AE) technique can detect and monitor the evolution of such failures. Industrial-size helium cryogenic systems employ cryogens often stored in gaseous form under pressure at ambient temperature. Standard initial and periodic pressure testing imposes operational constraints which other complementary testing methods, such as AE, could significantly alleviate. Recent reception testing of 250 m3 GHe storage vessels with a design pressure of 2.2 MPa for the LEP and LHC cryogenic systems has implemented AE with the above-mentioned aims

Physics Behind Precision

This document provides a writeup of contributions to the FCC-ee mini-workshop on "Physics behind precision" held at CERN, on 2-3 February 2016.Comment: https://indico.cern.ch/event/469561