2012/07/04 by Marcus Berg, Joseph P. Conlon, David Marsh +1
Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Coupling (piping) #F-theory #Flavour #Moduli #Orbifold #Quantum Chromodynamics and Particle Interactions #String (physics) #Superpotential #Yukawa potential #hep-th
paper · pdf · doi:10.1007/jhep02(2013)018
published as JHEP 1302:018,2013 · 37 pages + appendices, 8 figures
arxiv created 2012/07/04 · openalex publication_date 2013/02/01 · arxiv updated 2013/02/12 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Non-perturbative superpotential cross-couplings between visible sector matter and Kähler moduli can lead to significant flavour-changing neutral currents in compactifications of type IIB string theory. Here, we compute corrections to Yukawa couplings in orbifold models with chiral matter localised on D3-branes and non-perturbative effects on distant D7-branes. By evaluating a threshold correction to the D7-brane gauge coupling, we determine conditions under which the non-perturbative corrections to the Yukawa couplings appear. The flavour structure of the induced Yukawa coupling generically fails to be aligned with the tree-flavour structure. We check our results by also evaluating a correlation function of two D7-brane gauginos and a D3-brane Yukawa coupling. Finally, by calculating a string amplitude between n hidden scalars and visible matter we show how non-vanishing vacuum expectation values of distant D7-brane scalars, if present, may correct visible Yukawa couplings with a flavour structure that differs from the tree-level flavour structure.