The conjoined production at the LHC of single top and Higgs boson via t-channel weak boson exchange is ideal to probe the top-quark Yukawa coupling , due to a delicate cancellation between the amplitudes with the htt and the hWW couplings. We find that the top quark is produced with 100% polarization in the leading order, and its quantum state is determined by the spin-vector direction in the t-quark rest frame. We relate the spin direction to the four-momenta of the top, Higgs and a jet in the helicity amplitude framework. We identify a polarization asymmetry that is sensitive to CP violation, even after partial integration over the forward jet momentum . This CP violating asymmetry may be observed at the LHC via the component of the top-quark polarization that is perpendicular to the th scattering plane. Based on arXiv:1807.00281

Dr. Ya -Juan Zheng got Ph.D in particle physics at Shandong University in 2012 . She was a postdoctoral researcher in Taiwan University, Yonsei University , and in Toyama, Osaka, and Shimane Universities as a JSPS fellow . She will move to University of Kansas to further conduct research on collider and flavour physics.