Exploring charm decays with missing energy in leptoquark models

• Published in: The journal of high energy physics Vol. 2021; no. 4; pp. 1 - 16
• Main Authors: Faisel, Gaber, Su, Jhih-Ying, Tandean, Jusak
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.04.2021; Springer Nature B.V; SpringerOpen
• Subjects: Beyond Standard Model; Charm (particle physics); Classical and Quantum Gravitation; Effective Field Theories; Elementary Particles; Flavor (particle physics); Hadrons; Heavy Quark Physics; High energy physics; Neutrino Physics; Neutrinos; Particle decay; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Quarks; Regular Article - Theoretical Physics; Relativity Theory; Standard model (particle physics); String Theory; Heavy Quark Physics; Neutrino Physics; Effective Field Theories; Beyond Standard Model
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP04(2021)246

A bstract We investigate the possibility that scalar leptoquarks generate consequential effects on the flavor-changing neutral-current decays of charmed hadrons into final states with missing energy carried away by either standard model or sterile neutrinos. We focus on scenarios involving the R 2 , R ˜ 2 , and S ¯ 1 leptoquarks and take into account various pertinent constraints, learning that meson-mixing ones and those inferred from collider searches can be of significance. We find in particular that the branching fractions of charmed meson decays D → , M = π, ρ , and D s → and singly charmed baryon decays Λ c + → and Ξ c → are presently allowed to attain the 10 − 7 -10 − 6 levels if induced by R 2 and that the impact of R ˜ 2 is comparatively much less. In contrast, the contributions of S ¯ 1 , which couples to right-handed up-type quarks and the sterile neutrinos, could lead to branching fractions as high as order 10 − 3 . This suggests that these charmed hadron decays might be within reach of the BESIII and Belle II experiments or future super charm-tau factories and could serve as potentially promising probes of leptoquark interactions with sterile neutrinos.