Extraction of bare form factors for Bs →Kℓν decays in nonperturbative HQET
| Autor: | Rainer Sommer, Mateusz Koren, Hubert Simma, Fabio Bernardoni, Debasish Banerjee, Felix Bahr |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Nuclear and High Energy Physics
Particle physics High Energy Physics::Lattice clover [fermion] Wilson [quark] gap nonperturbative Euclidean 01 natural sciences quantum chromodynamics excited state 0103 physical sciences Heavy quark effective theory ddc:530 ground state correlation function flavor: 2 [quark] numerical calculations 010306 general physics Spectroscopy lattice form factor Physics Heavy Quark Effective Theory 010308 nuclear & particles physics Extraction (chemistry) Astronomy and Astrophysics Lattice QCD Atomic and Molecular Physics and Optics mass dependence [quark] gauge field theory semileptonic decay [B/s] |
| Zdroj: | International journal of modern physics / A 34(28), 1950166-(2019). doi:10.1142/S0217751X19501665 |
| ISSN: | 1793-656X 0217-751X |
| DOI: | 10.1142/s0217751x19501665 |
| Popis: | We discuss the extraction of the ground state $\langle \mathrm{K} ({\bf p})|V_\mu(0)|\mathrm{B} ({\bf 0})\rangle$ matrix elements from Euclidean lattice correlation functions. The emphasis is on the elimination of excited state contributions. Two typical gauge-field ensembles with lattice spacings $0.075, \; 0.05$ fm and pion masses $330,\;270$ MeV are used from the O($a$)- improved CLS 2-flavour simulations and the final state momentum is $|{\bf p}|=0.5\,{\rm GeV}$. The b-quark is treated in HQET including the $1/m_\mathrm{b}$ corrections. Fits to two-point and three-point correlation functions and suitable ratios including summed ratios are used, yielding consistent results with precision of around 2% which is $not$ limited by the $1/m_\mathrm{b}$ corrections but by the dominating static form factors. Excited state contributions are under reasonable control but are the bottleneck towards precision. We do not yet include a specific investigation of multi-hadron contaminations, a gap in the literature which ought to be filled soon. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|