Luka Leskovec (Avtor), Stefan Meinel (Avtor), Marcus Petschlies (Avtor), John W. Negele (Avtor), Srijit Paul (Avtor), Andrew Pochinsky (Avtor)

Povzetek

The decay $B \to \rho \ell \bar{\nu}$ is an attractive process for determining the magnitude of the smallest Cabibbo-Kobayashi-Maskawa matrix element, $|V_{ub}|$, and can provide new insights into the origin of the longstanding exclusive-inclusive discrepancy in determinations of this standard-model parameter. This requires a nonperturbative QCD calculation of the $B \to \rho$ form factors $V$, $A_0$, $A_1$, and $A_{12}$. The unstable nature of the $\rho$ resonance has prevented precise lattice QCD calculations of these form factors to date. Here, we present the first lattice QCD calculation of the $B \to \rho$ form factors in which the $\rho$ is treated properly as a resonance in $P$-wave $\pi \pi$ scattering. To this end, we use the Lellouch-Lüscher finite-volume formalism to compute the $B \to \pi \pi$ form factors as a function of both momentum transfer and $\pi \pi$ invariant mass, and then analytically continue to the $\rho$ resonance pole. This calculation is performed with 2 + 1 dynamical quark flavors at a pion mass of approximately 320 MeV, and demonstrates a clear path toward results at the physical point.

Ključne besede

fizika osnovnih delcev;interakcije delcev;kvantna kromodinamika na mreži;oblikovni faktorji;physics of elementary particles;particle interactions;lattice QCD;form factors;

Podatki

Jezik: Angleški jezik
Leto izida:
Tipologija: 1.01 - Izvirni znanstveni članek
Organizacija: UL FMF - Fakulteta za matematiko in fiziko
UDK: 539.120.811
COBISS: 234136323 Povezava se bo odprla v novem oknu
ISSN: 0031-9007
Št. ogledov: 49
Št. prenosov: 3
Ocena: 0 (0 glasov)
Metapodatki: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Ostali podatki

Sekundarni jezik: Slovenski jezik
Sekundarne ključne besede: fizika osnovnih delcev;interakcije delcev;kvantna kromodinamika na mreži;oblikovni faktorji;
Vrsta dela (COBISS): Članek v reviji
Strani: str. 161901-1-161901-8
Letnik: ǂVol. ǂ134
Zvezek: ǂiss. ǂ16
Čas izdaje: 2025
DOI: 10.1103/PhysRevLett.134.161901
ID: 26265070