Results 21 to 30 of about 1,411 (170)
Parity realization in vector-like theories from fermion bilinears [PDF]
Journal of High Energy Physics, 2008 We reconsider in this paper the old aim of trying to understand if the observed realization of discrete symmetries as Parity or CP in the QCD vacuum can be satisfied from first principles. We show how under the appropriate assumptions implicitely done by Vafa and Witten in their old paper on parity realization in vector-like theories, all parity and CP
Azcoiti, V., di Carlo, G., Vaquero, A.
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Wilson coefficients and natural zeros from the on-shell viewpoint
Journal of High Energy Physics, 2022 We show how to simplify the calculation of the finite contributions from heavy particles to EFT Wilson coefficients by using on-shell methods. We apply the technique to the one-loop calculation of g − 2 and Hγγ, showing how finite contributions can be ...
Luigi Delle Rose +2 more
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SU(5) × U(1)′ Models with a Vector-like Fermion Family [PDF]
Universe, 2021 Motivated by experimental measurements indicating deviations from the Standard Model predictions, we discuss F-theory-inspired models, which, in addition to the three chiral generations, contain a vector-like complete fermion family. The analysis takes place in the context of SU(5)×U(1)′ GUT embedded in an E8 covering group, which is associated with ...
A. Karozas +2 more
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Current status on pair-produced muon-philic vectorlike leptons in multilepton channels at the LHC
Journal of High Energy Physics, 2023 In this work, we obtain the current limits on the pair production of vectorlike leptons decaying to a Standard Model gauge boson and a lepton in the second generation using the Run-2 data at the LHC.
Junichiro Kawamura, Seodong Shin
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The two scales of new physics in Higgs couplings
Journal of High Energy Physics, 2023 Higgs coupling deviations from Standard Model predictions contain information about two scales of Nature: that of new physics responsible for the deviation, and the scale where new bosons must appear. The two can coincide, but they do not have to.
Raffaele Tito D’Agnolo +3 more
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Integrating out new fermions at one loop
Journal of High Energy Physics, 2021 We present the fermionic universal one-loop effective action obtained by integrating out heavy vector-like fermions at one loop using functional techniques. Even though previous approaches are able to handle integrating out heavy fermions with non-chiral
Andrei Angelescu, Peisi Huang
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Higgs vacuum stability with vectorlike fermions [PDF]
Physical Review D, 2019 We present the effects of vector-like fermions (VLF) on the stability of the Higgs electroweak vacuum, using the renormalization group improved Higgs effective potential. We review the calculation of the one-loop beta-functions of the standard model couplings, paying particular attention to the fermion contributions.
Gopalakrishna, Shrihari +1 more
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On a Standard Model Extension with Vector-like Fermions and Abelian Symmetry [PDF]
Communications in Physics, 2020 We investigate an extension of the standard model with vector-like fermions and an extra Abelian gauge symmetry. The particle mass spectrum is calculated explicitly. The Lagrangian terms for all the gauge interactions of leptons and quarks in the model are derived.
Hieu Minh Tran +2 more
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Pseudoscalar portal dark matter and new signatures of vector-like fermions [PDF]
Journal of High Energy Physics, 2016 Fermionic dark matter interacting with the Standard Model sector through a pseudoscalar portal could evade the direct detection constraints while preserving a WIMP miracle. We study the LHC constraints on the pseudoscalar production in simplified models with the pseudoscalar either dominantly coupled to b quarks or tau leptons and explore their ...
Fan, JiJi +2 more
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Partial compositeness under precision scrutiny
Journal of High Energy Physics, 2022 We revisit the impact of top partial compositeness on electroweak precision observables in the misaligned vacuum basis. We identify a new source for S in the singlet mixing case, and for S-T in the bi-doublet mixing, stemming from misalignment in the ...
Haiying Cai, Giacomo Cacciapaglia
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