International Science Index


Search for Flavour Changing Neutral Current Couplings of Higgs-up Sector Quarks at Future Circular Collider (FCC-eh)

Abstract:In the search for new physics beyond the Standard Model, Flavour Changing Neutral Current (FCNC) is a good research field in terms of the observability at future colliders. Increased Higgs production with higher energy and luminosity in colliders is essential for verification or falsification of our knowledge of physics and predictions, and the search for new physics. Prospective electron-proton collider constituent of the Future Circular Collider project is FCC-eh. It offers great sensitivity due to its high luminosity and low interference. In this work, thq FCNC interaction vertex with off-shell top quark decay at electron-proton colliders is studied. By using MadGraph5_aMC@NLO multi-purpose event generator, observability of tuh and tch couplings are obtained with equal coupling scenario. Upper limit on branching ratio of tree level top quark FCNC decay is determined as 0.012% at FCC-eh with 1 ab ^−1 luminosity.
[1] S. L. Glashow, J. Iliopoulos, and L.Maiani, “Weak Interactions with Lepton-Hadron Symmetry,” Phys. Rev. D, vol. 2, no 7, 1285, (1970).
[2] J. A. Aguilar-Saavedra, “Top flavour-changing neutral interactions: theoretical expectations and experimental detection,” Acta Phys. Polon. B 35, 2695-2710,2004, arXiv:0409342v4
[3] O. Bruning, J. Jowett, M. Klein, D. Pellegrini, D. Schulte, and F. Zimmermann, “Future Circular Collider Study FCC-he Baseline Parameters,” Tech. Rep. CERN-ACC-2017-0019, CERN, Geneva, Apr 2017.
[4] J. L. Abelleira Fernandez et al. (LHeC Study Group), “A Large Hadron Electron Collider At CERN,” J. Phys. G: Nucl. Part. Phys., vol. 39, 075001, June 2012.
[5] The ATLAS collaboration, Aad, G., Abbott, B. et al. J. High Energ. Phys. (2015) 2015: 1.
[6] The CMS collaboration, Khachatryan, V., Sirunyan, A.M. et al. J. High Energ. Phys. (2017) 2017: 79.
[7] J. Alwall et al, “The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations,” 2014, arXiv:1405.0301
[8] C. Degrande, C. Duhr, B. Fuks, D. Grellscheid, O. Mattelaer and T. Reiter, Comput. Phys. Commun., vol. 183, 1201-1214, June 2012, arXiv:1108.2040
[9] Mathieu Buchkremer, Giacomo Cacciapaglia, Aldo Deandrea, Luca Panizzi, “Model-independent framework for searches of top partners,” Nuclear Physics B, Vol. 876, Issue 2, pp. 376-417, Nov. 2013.
[10] Ling-Lie Chau and Wai-Yee Keung, “Comments on the Parametrization of the Kobayashi-Maskawa Matrix,” Phys. Rev. Lett. vol. 53, no. 4, 1802-1805, Nov. 1984.
[11] C. Patrignani et al. (Particle Data Group), Chin. Phys. C, vol. 40, 100001 (2016).
[12] Chong Sheng Li, Robert J. Oakes, and Tzu Chiang Yuan, “QCD corrections to t → W+ + b,” Phys. Rev. D, vol. 43, pp. 3759-3762, June 1991.
[13] Wei-Shu Hou, “Tree level t → ch0 or h0 → tc decays,” Physics Letters B, vol. 296, Issues 1–2, pp. 179-184, Dec. 1992.
[14] Wei Liu, Hao Sun, XiaoJuan Wang, Xuan Luo, “Probing the anomalous FCNC top-Higgs Yukawa couplings at the Large Hadron Electron Collider,” Phys. Rev. D, vol 92, , pp. 074015 1-10, Oct. 2015.
[15] XiaoJuan Wang, Hao Sun, and Xuan Luo, “Searches for the Anomalous FCNC Top-Higgs Couplings with Polarized Electron Beam at the LHeC,” Advances in High Energy Physics, vol. 2017, Article ID 4693213, pp.1-9, Mar. 2017.