Related papers: Testing $CP$ in the Bjorken process
Extra Higgs states appear in various scenarios beyond the current Standard Model of elementary particles. If discovered at the LHC or future colliders, the question will arise whether CP is violated or conserved in the extended scalar…
Since decays to four leptons is widely considered a promising way to search for the Higgs particle, we show how the same final state can also be used to search for signals of CP nonconservation. Energy asymmetries and triple correlations…
Possibilites for measuring the $J^{PC}$ quantum numbers of the Higgs particle through its interactions with gauge bosons and with fermions are discussed. Observables which indicate CP violation in these couplings are also identified.
We investigate the phenomenological constraints on a model where, besides the standard model Higgs sector, there is an effective new strong interaction acting on the third generation of quarks and characterized by a $\theta$-like term. This…
We present results of an investigation to study CP violation in the Higgs sector in $t\bar t$ production at a $\gamma\gamma$-collider, via the process $ \gamgam \ra \phi \ra t \bar t$ where the $\phi$ is a scalar with indeterminate CP…
A test of $CP$ invariance in Higgs boson production via vector-boson fusion has been performed in the $H\rightarrow\gamma\gamma$ channel using 139 fb$^{-1}$ of proton-proton collision data at $\sqrt{s}=13\,\mathrm{TeV}$ collected by the…
We evaluate the experimental sensitivity to the $CP$-odd admixture in the standard Higgs boson for the process $e^+e^-\to HZ$. The analysis is performed assuming the future lepton collider CEPC reference detector operating at…
In this paper we consider CP-violating new-physics contributions to the decay $t \to b \bar b c$. We examine the prospects for detecting such new physics at the LHC, which requires studying the process $gg \to t (\to b \bar b c) \bar t (\to…
Most studies of Higgs sector CP violation focus on the detection of CP-violating neutral Higgs-fermion Yukawa couplings, which yield P-odd, CP-violating phenomena. There is some literature on purely bosonic signatures of Higgs sector CP…
In this paper, we study the extent to which CP parity of a Higgs boson, and more generally its anomalous couplings to gauge bosons, can be measured at the LHC and a future electron-positron collider. We consider several processes, including…
Now that the Higgs particle has been observed by the ATLAS and CMS experiments at the LHC, the next endeavour would be to probe its fundamental properties and to measure its couplings to fermions and gauge bosons with the highest possible…
A search for the violation of the charge-parity ($CP$) symmetry in the production of top quarks in association with Z bosons is presented, using events with at least three charged leptons and additional jets. The search is performed in a…
Current experiments do not support, as ATLAS and CMS collaborations at the Large Hadron Collider reported, that the Higgs-like resonance discovered in July 2012 is a pure CP-odd state. We examine a general $hZZ$ vertex which contains…
Precise measurements of the $B_s^0 - \overline{B}_s^0$ mixing parameters provide a powerful test of the Standard Model, offering potential hints to new physics. The LHCb collaboration has performed updated measurements of the $CP$-violating…
We present a collection of $\mathrm{CP}$-odd observables for the process $pp\to t\,\left(\rightarrow b {\ell}^+ \nu_{\ell}\right) \bar{t}\,\left(\rightarrow \bar{b} {\ell}^-{\bar{\nu}}_{\ell}\right)\,H$ that are linearly dependent on the…
We investigate a potentially large CP violating asymmetry in the neutral Higgs boson decay into a heavy quark pair or a $W^+$--$W^-$ pair. The source of the CP nonconservation is in the Yukawa couplings of the Higgs boson which can contain…
One of the main goals of the LHCb experiment is to determine the mixing-induced $CP$ violating phase $\phi_s$ in $b \rightarrow c\bar{c}s$ transitions. Assuming the Standard Model, $\phi_s$ is precisely predicted, hence new physics could…
Measuring charge-parity (CP) violation in Higgs-fermion interactions is a key target of future precision Higgs programs. The decay $H\to\tau\tau$ is particularly sensitive to the CP structure of the Higgs Yukawa coupling via $\tau$ spin…
Generically, non-Standard-Model particles contribute to processes with order-one charge-parity (CP) violating phases, as CP is not a fundamental symmetry of nature. The exploration of CP violation becomes therefore a sensitive search for…
We study possible effects of CP violation in the Higgs sector on $t\bar t$ production at a $\gamma\gamma$-collider. These studies are performed in a model-independent way in terms of six form-factors $\{\Re(S_{\gamma}), \Im(S_{\gamma}),…