Related papers: An Indirect Handle on the Down-Quark Yukawa Coupli…
In this paper, we study the anomalous flavor changing neutral current Yukawa interactions between the top quark, the Higgs boson, and either an up or charm quark ($\rm tqH, q=u, c$). We probe these couplings in $\rm e^- p\rightarrow \nu_e…
The top quark flavor changing neutral current (FCNC) process is an excellent probe to search for new physics in top sector since the Standard Model expectation is extremely suppressed. We explore Higgs-mediated top quark FCNC, focusing on…
Large top quark flavor changing through neutral currents is expected by many extensions of the standard model. Direct and indirect searches for flavor changing neutral currents (FCNC) in the top quark decays to an up type quark (up,charm)…
Measuring the fermion Yukawa coupling constants is important for understanding the origin of the fermion masses and its relationship to the spontaneously electroweak symmetry breaking. On the other hand, some new physics models will change…
In the framework of the Standard Model Effective Field Theory, we compare the lower bounds on the scale of new physics possibly contributing to the $f\bar{f}h$ effective couplings, obtained from the measurements of different observables,…
Although the 125 GeV Higgs boson discovered at the LHC is often heralded as the origin of mass, it may not in fact be the origin of Yukawa couplings. In alternative models, Yukawa couplings may instead arise from a seesaw type mechanism…
We consider the issue of the top quark Yukawa coupling measurement in a model in dependent and general case with the inclusion of CP-violation in the coupling. Arguably the best process to study this coupling is the associa ted production…
The study of the Higgs boson properties is one of the most relevant activities in current particle physics. In particular, the Higgs boson couplings to third generation fermions is an important test of the mechanism of mass generation. In…
Yukawa couplings of the first quark generation are notoriously difficult to constrain due to their small values within the Standard Model. Here we propose Higgs off-shell production, with the Higgs boson decaying to four leptons, as a probe…
We study the alignment of Yukawa couplings in the framework of general two Higgs doublet models (2HDMs) considering a scenario in which the lightest neutral Higgs boson is purely CP even while the two heavier neutral Higgs bosons are…
Low-energy experiments involving kaon, B-meson, D-meson, and hyperon flavor-changing neutral transitions have confirmed the loop-induced flavor-changing neutral current (FCNC) picture of the standard model (SM). The continuing study of…
We study the constraints on $t\to u$ flavor changing neutral Higgs (FCNH) coupling, and how it may be explored further at the Large Hadron Collider (LHC). In the general two Higgs doublet model, such transitions can be induced by a nonzero…
One of the puzzles of the SM is the large hierarchy between the Yukawa couplings of different flavours. Yukawa couplings of the first and the second generation are constrained only very weakly so far. However, one can obtain large…
We constrain the Higgs boson (Yukawa) coupling to quarks in the first two generations in the $H\to ZZ$ final states. Deviation of these couplings from the Standard Model values leads to change in the Higgs boson width and in the cross…
The coupling of the Higgs boson to first and second generation fermions has yet to be measured experimentally. There still could be very large deviations in these couplings, as the origin of flavor is completely unknown. Nevertheless, if…
We show that both flavor-conserving and flavor-violating Yukawa couplings of the Higgs boson to first- and second-generation quarks can be probed by measuring rare decays of the form h->MV, where M denotes a vector meson and V indicates…
The Top Yukawa coupling profoundly influences several core mysteries linked to the electroweak scale and the Higgs boson. We study the feasibility of measuring the Top Yukawa coupling at high-energy muon colliders by examining the…
In multi-Higgs-doublet models, the alignment in flavour space of all Yukawa matrices coupling to a given right-handed fermion guarantees the absence of tree-level flavour-changing neutral couplings, while introducing new sources of CP…
Experimental study at LHC of the possible Higgs boson should soon provide accurate estimates of the Yukawa couplings $Y_{H\bar{f}f}$ for $f=t,b,\tau$. In the presence of a non-abelian discrete flavor symmetry $G_F$ (e.g. T') the usual…
We discuss scenarios with wrong-sign (WS) Yukawa couplings for the discovered Higgs boson in the Yukawa-aligned two Higgs doublet model. In the WS scenario, Yukawa couplings for down-type quarks and/or charged leptons have an opposite sign…