###
Λ _{b}→pl⁻ν¯ _{l} form factors from lattice QCD with static b quarks

We present a lattice QCD calculation of form factors for the decay Λ

_{b}→pμ⁻ν¯_{μ}, which is a promising channel for determining the Cabibbo-Kobayashi-Maskawa matrix element |V_{ub}| at the Large Hadron Collider. In this initial study we work in the limit of static b quarks, where the number of independent form factors reduces to two. We use dynamical domain-wall fermions for the light quarks, and perform the calculation at two different lattice spacings and at multiple values of the light-quark masses in a single large volume. Using our form factor results, we calculate the Λ_{b}→pμ⁻ν¯_{μ}differential decay rate in the range 14 GeV²≤q²≤q²_{max}, and obtain the integral ∫^{q²max}_{14 GeV²}[dΓ/dq²]dq²/|V_{ub}|²=15.3±4.2 ps⁻¹. Combined with future experimental data, this will give a novel determination of |V_{ub}| with about 15% theoretical uncertainty. The uncertainty is dominated by the use of the static approximation for the b quark, and can be reduced further by performing the lattice calculation with a more sophisticated heavy-quark action.- Publication Date:

- Type:
- Publisher's Accepted Manuscript

- Journal Name:
- Physical Review. D, Particles, Fields, Gravitation and Cosmology

- Additional Journal Information:
- Journal Name: Physical Review. D, Particles, Fields, Gravitation and Cosmology Journal Volume: 88 Journal Issue: 1; Journal ID: ISSN 1550-7998

- Publisher:
- American Physical Society

- Sponsoring Org:
- USDOE

- Country of Publication:
- United States

- Language:
- English

- OSTI Identifier:
- 1104294

```
Detmold, William, Lin, C.-J. David, Meinel, Stefan, and Wingate, Matthew.
```*Λb→pl⁻ν¯l form factors from lattice QCD with static b quarks*. United States: N. p.,
Web. doi:10.1103/PhysRevD.88.014512.

```
Detmold, William, Lin, C.-J. David, Meinel, Stefan, & Wingate, Matthew.
```*Λb→pl⁻ν¯l form factors from lattice QCD with static b quarks*. United States. doi:10.1103/PhysRevD.88.014512.

```
Detmold, William, Lin, C.-J. David, Meinel, Stefan, and Wingate, Matthew. 2013.
"Λb→pl⁻ν¯l form factors from lattice QCD with static b quarks". United States.
doi:10.1103/PhysRevD.88.014512.
```

```
@article{osti_1104294,
```

title = {Λb→pl⁻ν¯l form factors from lattice QCD with static b quarks},

author = {Detmold, William and Lin, C.-J. David and Meinel, Stefan and Wingate, Matthew},

abstractNote = {We present a lattice QCD calculation of form factors for the decay Λb→pμ⁻ν¯μ, which is a promising channel for determining the Cabibbo-Kobayashi-Maskawa matrix element |Vub| at the Large Hadron Collider. In this initial study we work in the limit of static b quarks, where the number of independent form factors reduces to two. We use dynamical domain-wall fermions for the light quarks, and perform the calculation at two different lattice spacings and at multiple values of the light-quark masses in a single large volume. Using our form factor results, we calculate the Λb→pμ⁻ν¯μ differential decay rate in the range 14 GeV²≤q²≤q²max, and obtain the integral ∫q²max 14 GeV²[dΓ/dq²]dq²/|Vub|²=15.3±4.2 ps⁻¹. Combined with future experimental data, this will give a novel determination of |Vub| with about 15% theoretical uncertainty. The uncertainty is dominated by the use of the static approximation for the b quark, and can be reduced further by performing the lattice calculation with a more sophisticated heavy-quark action.},

doi = {10.1103/PhysRevD.88.014512},

journal = {Physical Review. D, Particles, Fields, Gravitation and Cosmology},

number = 1,

volume = 88,

place = {United States},

year = {2013},

month = {7}

}