16,105 research outputs found

    Closing the light gluino gap with electron-proton colliders

    Get PDF
    The future electron-proton collider proposals, LHeC and FCC-he, can deliver O\mathcal{O}(TeV) center-of-mass energy collisions, higher than most of the proposed lepton accelerators, with O\mathcal{O}(ab−1^{-1}) luminosity, while maintaining a much cleaner experimental environment as compared to the hadron machines. This unique capability of e−pe^- p colliders can be harnessed in probing BSM scenarios giving final states that look like hadronic noise at pppp machines. In the present study, we explore the prospects of detecting such a prompt signal having multiple soft jets at the LHeC. Such a signal can come from the decay of gluino in RPV or Stealth SUSY, where there exists a gap in the current experimental search with mg~≈50−70m_{\tilde{g}} \approx 50 - 70 GeV. We perform a simple analysis to demonstrate that, with simple signal selection cuts, we can close this gap at the LHeC at 95 % confidence level, even in the presence of a reasonable systematic error. More sophisticated signal selection strategies and detailed knowledge of the detector can be used to improve the prospects of signal detection.Comment: 7 pages, 5 figure

    Studies of Quantum Chromodynamics at the LHC

    Full text link
    A successful description of hadron-hadron collision data demands a profound understanding of quantum chromodynamics. Inevitably, the complexity of strong-interaction phenomena requires the use of a large variety of theoretical techniques -- from perturbative cross-section calculations up to the modelling of exclusive hadronic final states. Together with the unprecedented precision of the data provided by the experiments in the first running period of the LHC, a solid foundation of hadron-hadron collision physics at the TeV scale could be established that allowed the discovery of the Higgs boson and that is vital for estimating the background in searches for new phenomena. This chapter on studies of quantum chromodynamics at the LHC is part of a recent book on the results of LHC Run 1 and presents the advances in theoretical methods side-by-side with related key measurements in an integrated approach.Comment: 49 pages, 24 figures, To appear in "The Large Hadron Collider -- Harvest of Run 1", Thomas Sch\"orner-Sadenius (ed.), Springer, 2015 (532 pages, 253 figures; ISBN 978-3-319-15001-7, for more details, see http://www.springer.com/de/book/9783319150000

    Top-Quark Physics at the LHC

    Full text link
    The top quark is the heaviest of all known elementary particles. It was discovered in 1995 by the CDF and D0 experiments at the Tevatron. With the start of the LHC in 2009, an unprecedented wealth of measurements of the top quark's production mechanisms and properties have been performed by the ATLAS and CMS collaborations, most of these resulting in smaller uncertainties than those achieved previously. At the same time, huge progress was made on the theoretical side yielding significantly improved predictions up to next-to-next-to-leading order in perturbative QCD. Due to the vast amount of events containing top quarks, a variety of new measurements became feasible and opened a new window to precisions tests of the Standard Model and to contributions of new physics. In this review, originally written for a recent book on the results of LHC Run 1, top-quark measurements obtained so far from the LHC Run 1 are summarised and put in context with the current understanding of the Standard Model.Comment: 35 pages, 25 figures. To appear in "The Large Hadron Collider -- Harvest of Run 1", Thomas Sch\"orner-Sadenius (ed.), Springer, 2015 (532 pages, 253 figures; ISBN 978-3-319-15000-0; eBook ISBN 978-3-319-15001-7, for more details, see http://www.springer.com/de/book/9783319150000

    QCD and γ γ\gamma\,\gamma studies at FCC-ee

    Full text link
    The Future Circular Collider (FCC) is a post-LHC project aiming at searches for physics beyond the SM in a new 80--100~km tunnel at CERN. Running in its first phase as a very-high-luminosity electron-positron collider (FCC-ee), it will provide unique possibilities for indirect searches of new phenomena through high-precision tests of the SM. In addition, by collecting tens of ab−1^{-1} integrated luminosity in the range of center-of-mass energies s\sqrt{s}~=90--350~GeV, the FCC-ee also offers unique physics opportunities for precise measurements of QCD phenomena and of photon-photon collisions through, literally, billions of hadronic final states as well as unprecedented large fluxes of quasireal γ\gamma's radiated from the e+e−\rm e^+e^- beams. We succinctly summarize the FCC-ee perspectives for high-precision extractions of the QCD coupling, for detailed analyses of parton radiation and fragmentation, and for SM and BSM studies through γγ\gamma\gamma collisions.Comment: 6 pages, Proceedings ICHEP'16 (Chicago
    • …
    corecore