4 research outputs found
Pseudoscalar top-Higgs coupling: Exploration of -odd observables to resolve the sign ambiguity
We present a collection of -odd observables for the process
that
are linearly dependent on the scalar () and pseudoscalar
() top-Higgs coupling and hence sensitive to the
corresponding relative sign. The proposed observables are based on triple
product (TP) correlations that we extract from the expression for the
differential cross section in terms of the spin vectors of the top and antitop
quarks. In order to explore other possibilities, we progressively modify these
TPs, first by combining them, and then by replacing the spin vectors by the
lepton momenta or the and momenta by their visible parts. We
generate Monte Carlo data sets for several benchmark scenarios, including the
Standard Model (, ) and two scenarios with
mixed properties (, ).
Assuming an integrated luminosity that is consistent with that envisioned for
the High Luminosity Large Hadron Collider, using Monte Carlo-truth and taking
into account only statistical uncertainties, we find that the most promising
observable can disentangle the "-mixed" scenarios with an
effective separation of . In the case of observables that do not
require the reconstruction of the and momenta, the power of
discrimination is up to for the same number of events. We also
show that the most promising observables can still disentangle the
-mixed scenarios when the number of events is reduced to values
consistent with expectations for the Large Hadron Collider in the near term.Comment: 28 pages, 7 figures. Published versio
Pseudoscalar top-Higgs coupling: exploration of CP-odd observables to resolve the sign ambiguity
We present a collection of CP-odd observables for the process ppât(âbâ+Îœâ)tÂŻ(âbÂŻââÎœÂŻâ) H that are linearly dependent on the scalar (kt) and pseudoscalar (kËt) top-Higgs coupling and hence sensitive to the corresponding relative sign. The proposed observables are based on triple product (TP) correlations that we extract from the expression for the differential cross section in terms of the spin vectors of the top and antitop quarks. In order to explore other possibilities, we progressively modify these TPs, first by combining them, and then by replacing the spin vectors by the lepton momenta or the t and tÂŻ momenta by their visible parts. We generate Monte Carlo data sets for several benchmark scenarios, including the Standard Model (kt = 1, kËt= 0) and two scenarios with mixed CP properties (kt = 1, kËt = ± 1). Assuming an integrated luminosity that is consistent with that envisioned for the High Luminosity Large Hadron Collider, using Monte Carlo-truth and taking into account only statistical uncertainties, we find that the most promising observable can disentangle the âCP-mixedâ scenarios with an effective separation of ⌠19Ï. In the case of observables that do not require the reconstruction of the t and tÂŻ momenta, the power of discrimination is up to ⌠13Ï for the same number of events. We also show that the most promising observables can still disentangle the CP-mixed scenarios when the number of events is reduced to values consistent with expectations for the Large Hadron Collider in the near term.Facultad de Ciencias ExactasInstituto de FĂsica La Plat