16,105 research outputs found
Closing the light gluino gap with electron-proton colliders
The future electron-proton collider proposals, LHeC and FCC-he, can deliver
(TeV) center-of-mass energy collisions, higher than most of the
proposed lepton accelerators, with (ab) luminosity, while
maintaining a much cleaner experimental environment as compared to the hadron
machines. This unique capability of colliders can be harnessed in
probing BSM scenarios giving final states that look like hadronic noise at
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 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
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
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 studies at FCC-ee
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 integrated luminosity in the range of center-of-mass energies
~=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 's radiated from the 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 collisions.Comment: 6 pages, Proceedings ICHEP'16 (Chicago
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