Central-edge asymmetry as a probe of Higgs-top coupling in ttˉht\bar{t}h production at LHC

The Higgs-top coupling plays a central role in the hierarchy problem and the vacuum stability of the Standard Model (SM). We propose a central-edge asymmetry ($A_{CE}$) to probe the CP violating Higgs-top coupling in dileptonic channel of $t\bar{t}h(\to b\bar{b})$ production at the LHC. We demonstrate that the CP-violating Higgs-top coupling can affect the central-edge asymmetry through distorting $\Delta y_{\ell^+\ell^-}$ distribution because of the contribution of new top charge asymmetric term. Since $\Delta y_{\ell^+\ell^-}$ distribution is frame-independent and has a good discrimination even in boosted regime, we use the jet substructure technique to enhance the observability of the dileptonic channel of $t\bar{t}h$ production. We find that (1) the significance of dileptonic channel of $t\bar{t}h$ production can reach $5\sigma$ for CP phase $\xi=0,\pi/4,\pi/2$ when the luminosity ${\cal L}=795,993,1276$ fb$^{-1}$ at 14 TeV LHC. (2) the central-edge asymmetry $A_{CE}$ show a good discrimination power of CP phase of $t\bar{t}h$ interaction, which are -40.26\%, -26.60\%, -9.47\% for $\xi=0$, $\pi/4$, $\pi/2$ respectively and are hardly affected by the event selections. Besides, by performing the binned-$\chi^2$ analysis of $\Delta y_{\ell^+\ell^-}$ distribution, we find that the scalar and pseudo-scalar interactions can be distinguished at 95\% C.L. level at 14 TeV HL-LHC.Comment: minor changes, version accepted by PL

Trade of agricultural products between China and Australia: tendency and prospects

Trade between China and Australia has been fast expanding in the recent decade and China has now become Australia's second-largest export market In particular, Australia's agricultural exports to China have increased rapidly and have almost trebled over the past decade, reaching A$2.5 billion in 2004. This makes China Australia's third-largest agricultural export market. China's demand for agricultural commodities is expected to continue to rise, driven by the effects of fast economic growth, higher incomes and rapid urbanisation. China's increasing demand for agricultural products presents enormous opportunities for Australian agricultural exports to this growing market. To best capture the emerging opportunities, it is pertinent for Australian agricultural industries to gain an in-depth understanding of the changing patterns of agricultural trade between Australia and China and the driving forces behind such dynamics. In this paper, we investigate the major trends of and changes in the bilateral agricultural trade between Australia and China and examine trade intensity, intra-industry trade and comparative advantages associated with the two countries' agricultural trade. Implications for promoting future agricu1tural trade and cooperation between Australia and China are drawn