Three-particle distribution in the B meson and charm-quark loops in FCNC B decays

Author(s)
Dmitri Melikhov
Abstract

We discuss a nonfactorizable (NF) contribution of a charm loop to the FCNC B-decay amplitude given through the three-particle Bethe-Salpeter amplitude (3BS) of the B-meson. This 3BS contains one heavy-quark field and two light fields (a light quark and a gluon). Our discussion is aimed at clarifying properties of the B-meson 3BS necessary to describe properly charm-loop contributions to the amplitudes of FCNC B-decays. We demonstrate that the dominant contribution of nonfactorizable charm to FCNC B-decay amplitude is given in the heavy-quark limit by a convolution of some hard kernel and the B-meson 3BS in a "double-collinear"light cone (LC) configuration: one of the light degrees of freedom φ(x), x2=0, lies on the (+)-direction of the LC, whereas another light degree of freedom φ′(x′), x′2=0 lies along the (-)-direction. We show the emergence of new constraints on the distribution amplitudes which parametrize the 3BS in this double-collinear configuration.

Organisation(s)
Particle Physics
External organisation(s)
Anuchin Research Institute and Museum of Anthropology, Universität Wien, Joint Institute for Nuclear Research
Journal
Physical Review D
Volume
108
No. of pages
11
ISSN
2470-0010
DOI
https://doi.org/10.1103/PhysRevD.108.034007
Publication date
08-2023
Peer reviewed
Yes
Austrian Fields of Science 2012
103034 Particle physics
ASJC Scopus subject areas
Nuclear and High Energy Physics
Portal url
https://ucris.univie.ac.at/portal/en/publications/threeparticle-distribution-in-the-b-meson-and-charmquark-loops-in-fcnc-b-decays(3b289d15-120d-4a01-b13f-48ac9cb5a7a3).html