2014/04/30 by B. Blossier, Blossier, Benoit
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.1405.0005
openalex publication_date 2014/04/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The 2-years old observation at LHC of a new boson, with a mass of 126 GeV, is\na great achievement. Its interpretation as a Brout-Englert-Higgs boson is very\nplausible and appealing to complete the zoology of fundamental particles in the\nStandard Model. The interplay between theorists and experimentalists that we\nhave witnessed has come with a huge work to determine with enough precision the\nparameters of the Standard Model: couplings, masses, mixing angles. Among the\nvarious tools developed by physicists, lattice QCD is particularly suitable to\nknow those parameters in the quark sector. In this report I discuss the lattice\nmeasurement of Standard Model fundamental parameters that are closely related\nto Higgs boson: its main production mode is the gluon-gluon fusion, whose the\nmagnitude is governed by the strong coupling constant, while its most favored\ndecay channel, H \→ b \b, has a coupling proportional to the b quark\nmass. I outline the improvements brought by the lattice community: simulations\nwith Nf=2+1+1 dynamical quarks are crucial to study how much the charm quark\nimpacts the strong coupling constant calculation. A non perturbative matching\nbetween Heavy Quark Effective Theory and QCD is welcome to handle in an\nappropriate way the b quark physics. An extensive methodological exploration\nis necessary to get rid of contribution from excited states in correlation\nfunctions computed to extract hadron masses and decay constants. The effort to\nmeasure the u/d, s and c quark masses is also discussed, illustrating the\nbenefit of using an automatic O(a) improved lattice regularization.\n