New vector-like quarks can have sizable couplings to first generation quarks without conflicting with current experimental constraints. The coupling with valence quarks and unique kinematics make ...single production the optimal discovery process. We perform a model-independent analysis of the discovery reach at the Large Hadron Collider for new vector-like quarks considering single production and subsequent decays via electroweak interactions. An early LHC run with 7 TeV center of mass energy and 1 fb
−1
of integrated luminosity can probe heavy quark masses up to 1 TeV and can be competitive with the Tevatron reach of 10 fb
−1
. The LHC with 14 TeV center of mass energy and 100 fb
−1
of integrated luminosity can probe heavy quark masses up to 3.7 TeV for order one couplings.
A
bstract
New vector-like quarks can mix sizeably with first generation Standard Model quarks without conflicting with current experimental constraints. Searches for such new quarks have been ...performed in pair production and electroweak single production channels with subsequent decays into electroweak gauge bosons. To fully explore the underlying structure of the theory the channels with heavy quark decays into Higgs bosons are crucial and in this article we consider for the first time the LHC reach for such channels. The two main production mechanisms involve single production of new quarks through the fusion of a vector boson and the Higgs and single production in association with a Higgs boson. We show that both channels have promising reach at the LHC and that they complement the current direct searches involving decays into electroweak gauge bosons.
The search for heavy Majorana neutrinos Atre, Anupama; Han, Tao; Pascoli, Silvia ...
The journal of high energy physics,
05/2009, Letnik:
2009, Številka:
5
Journal Article
In the Standard Model of strong and electroweak interactions, neutrinos are strictly massless due to the absence of the right-handed chiral states and the requirement of gauge invariance and ...renormalizability. However, recent neutrino oscillation experiments have provided strong evidence that neutrinos are massive and their flavors defined with respect to the charged leptons oscillate, presenting a pressing need for physics beyond the Standard Model. We do not know the nature of mass generation; in particular, we do not know if neutrinos are of Dirac or Majorana type-the former preserves lepton number and the latter violates it by two units. Although the prevailing theoretical prejudice prefers Majorana neutrinos, experimentally testing the Dirac or Majorana nature of neutrinos is of fundamental importance. The unambiguous proof of the existence of a Majorana neutrino is the observation of a lepton number violating process. Since neutrinos interact so weakly and leave no trace in ordinary detectors, the only appropriate signatures must involve two like-sign charged leptons for a process that violates lepton number by two units. To establish the Majorana nature of neutrinos definitively many low energy and collider processes that probe Majorana neutrino masses over many orders of magnitude, from sub-electron-volt to hundreds of giga-electron-volt have been studied.
Thesis (Ph.D.)--University of Wisconsin--Madison, 2007.
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New vector-like quarks can mix sizably with first generation Standard Model quarks without conflicting with current experimental constraints. Searches for such new quarks have been performed in pair ...production and electroweak single production channels with subsequent decays into electroweak gauge bosons. To fully explore the underlying structure of the theory the channels with heavy quark decays into Higgs bosons are crucial and in this article we consider for the first time the LHC reach for such channels. The two main production mechanisms involve single production of new quarks through the fusion of a vector boson and the Higgs and single production in association with a Higgs boson. We show that both channels have promising reach at the LHC and that they complement the current direct searches involving decays into electroweak gauge bosons.