Publication

New Theory Paper

November 18, 2020

Theory Division

“A new B-flavour anomaly in Bd,s->K0 anti-K0: anatomy and interpretation” by M. Algueró, A. Crivellin, S. Descotes-Genon, J. Matias and M. Novoa-Brunet. has been submitted to the arXiv.

We identify a new anomaly in an observable that we called L, constructed upon the longitudinal amplitudes of the non-leptonic decays Bd->K0* anti K0* versus Bs->K0* anti K0*. This observable is protected from leading order infrared divergences in hard-scattering and weak annihilation diagrams and exihibits a 2.6 sigma tension with data.

We establish a parallelism with RK of semileptonic B decays interchanging leptons by quarks and we identify the dominant Wilson coefficient in an EFT approach that could explain the anomaly with a 25% NP contribution.

Latest Group News

New publication

New theory paper on CP violation

May 25, 2022

New-physics signatures via CP violation in η (0) → π 0 µ + µ − and η 0 → ηµ + µ − decays” by R. Escribano, E. Royo and P. Sánchez-Puertas has been published in JHEP.

New publication

New theory paper on the muon anomalous magnetic moment

May 18, 2022

Evaluation of the three-flavor quark-disconnected contribution to the muon anomalous magnetic moment from experimental data” by S. Peris, M. Golterman (IFAE visitor) and collaborators has been published at Physical Review D. The article is highlighted as an Editor’s Suggestion.

New Member

New Member in the Theory group

May 11, 2022

Mario Herrero has just joined the Theory group as a Juan de la Cierva Postdoc researcher.