Prospects for a lattice calculation of the rare decay Σ+ → pℓ + ℓ −

Abstract We present a strategy for calculating the rare decay of a Σ+(uus) baryon to a proton (uud) and di-lepton pair using lattice QCD. To determine this observable one needs to numerically evaluate baryonic two-, three-, and four-point correlation functions related to the target process. In parti...

Full description

Bibliographic Details
Main Authors: Felix Erben, Vera Gülpers, Maxwell T. Hansen, Raoul Hodgson, Antonin Portelli
Format: Article
Language:English
Published: SpringerOpen 2023-04-01
Series:Journal of High Energy Physics
Subjects:
Online Access:https://doi.org/10.1007/JHEP04(2023)108
_version_ 1797769736896905216
author Felix Erben
Vera Gülpers
Maxwell T. Hansen
Raoul Hodgson
Antonin Portelli
author_facet Felix Erben
Vera Gülpers
Maxwell T. Hansen
Raoul Hodgson
Antonin Portelli
author_sort Felix Erben
collection DOAJ
description Abstract We present a strategy for calculating the rare decay of a Σ+(uus) baryon to a proton (uud) and di-lepton pair using lattice QCD. To determine this observable one needs to numerically evaluate baryonic two-, three-, and four-point correlation functions related to the target process. In particular, the four-point function arises from the insertion of incoming and outgoing baryons, together with a weak Hamiltonian mediating the s → d transition and an electromagnetic current creating the outgoing leptons. As is described in previous work in other contexts, this four-point function has a highly non-trivial relation to the physical observable, due to proton and proton-pion intermediate states. These lead to growing Euclidean time dependence and, in the case of the two-particle intermediate states, to power-like volume effects. We discuss how to treat these issues in the context of the Σ+ → pℓ + ℓ − decay and, in particular, detail the relation between the finite-volume estimator and the physical, complex-valued amplitude. In doing so, we also make connections between various approaches already described in the literature.
first_indexed 2024-03-12T21:13:19Z
format Article
id doaj.art-d00d30308c774e5cb353eaefcf87249f
institution Directory Open Access Journal
issn 1029-8479
language English
last_indexed 2024-03-12T21:13:19Z
publishDate 2023-04-01
publisher SpringerOpen
record_format Article
series Journal of High Energy Physics
spelling doaj.art-d00d30308c774e5cb353eaefcf87249f2023-07-30T11:03:59ZengSpringerOpenJournal of High Energy Physics1029-84792023-04-012023414010.1007/JHEP04(2023)108Prospects for a lattice calculation of the rare decay Σ+ → pℓ + ℓ −Felix Erben0Vera Gülpers1Maxwell T. Hansen2Raoul Hodgson3Antonin Portelli4School of Physics and Astronomy, University of EdinburghSchool of Physics and Astronomy, University of EdinburghSchool of Physics and Astronomy, University of EdinburghSchool of Physics and Astronomy, University of EdinburghSchool of Physics and Astronomy, University of EdinburghAbstract We present a strategy for calculating the rare decay of a Σ+(uus) baryon to a proton (uud) and di-lepton pair using lattice QCD. To determine this observable one needs to numerically evaluate baryonic two-, three-, and four-point correlation functions related to the target process. In particular, the four-point function arises from the insertion of incoming and outgoing baryons, together with a weak Hamiltonian mediating the s → d transition and an electromagnetic current creating the outgoing leptons. As is described in previous work in other contexts, this four-point function has a highly non-trivial relation to the physical observable, due to proton and proton-pion intermediate states. These lead to growing Euclidean time dependence and, in the case of the two-particle intermediate states, to power-like volume effects. We discuss how to treat these issues in the context of the Σ+ → pℓ + ℓ − decay and, in particular, detail the relation between the finite-volume estimator and the physical, complex-valued amplitude. In doing so, we also make connections between various approaches already described in the literature.https://doi.org/10.1007/JHEP04(2023)108Algorithms and Theoretical DevelopmentsHadronic Matrix Elements and Weak DecaysLattice QCD
spellingShingle Felix Erben
Vera Gülpers
Maxwell T. Hansen
Raoul Hodgson
Antonin Portelli
Prospects for a lattice calculation of the rare decay Σ+ → pℓ + ℓ −
Journal of High Energy Physics
Algorithms and Theoretical Developments
Hadronic Matrix Elements and Weak Decays
Lattice QCD
title Prospects for a lattice calculation of the rare decay Σ+ → pℓ + ℓ −
title_full Prospects for a lattice calculation of the rare decay Σ+ → pℓ + ℓ −
title_fullStr Prospects for a lattice calculation of the rare decay Σ+ → pℓ + ℓ −
title_full_unstemmed Prospects for a lattice calculation of the rare decay Σ+ → pℓ + ℓ −
title_short Prospects for a lattice calculation of the rare decay Σ+ → pℓ + ℓ −
title_sort prospects for a lattice calculation of the rare decay σ pl l
topic Algorithms and Theoretical Developments
Hadronic Matrix Elements and Weak Decays
Lattice QCD
url https://doi.org/10.1007/JHEP04(2023)108
work_keys_str_mv AT felixerben prospectsforalatticecalculationoftheraredecayspll
AT veragulpers prospectsforalatticecalculationoftheraredecayspll
AT maxwellthansen prospectsforalatticecalculationoftheraredecayspll
AT raoulhodgson prospectsforalatticecalculationoftheraredecayspll
AT antoninportelli prospectsforalatticecalculationoftheraredecayspll