Publications
Publication Information
| Title | A dispersive treatment of $K_{\ell 4}$ decays |
| Authors | Peter Stoffer, Gilberto Colangelo, Emilie Passemar |
| JLAB number | JLAB-THY-17-2489 |
| LANL number | (None) |
| Other number | DOE/OR/23177-4162 |
| Document Type(s) | (Meeting) |
| Associated with EIC: | No |
| Supported by Jefferson Lab LDRD Funding: | No |
| Funding Source: | Nuclear Physics (NP) |
|
Meeting Paper compiled for KAON 2016 Proceedings Proceedings of KAON2016 Edited By IoP (2017) Refereed Page(s) 012026 | |
| Publication Abstract: | K_l4 decays have several features of interest: they allow an accurate measurement of pipi-scattering lengths, the decay is the best source for the determination of some low-energy constants of chiral perturbation theory (XPT), one form factor of the decay is connected to the chiral anomaly. We present the results of our dispersive analysis of decays, which provides a resummation of pipi- and Kpi-rescattering effects. The free parameters of the dispersion relation are fitted to the data of the high-statistics experiments E865 and NA48/2. By matching to XPT at NLO and NNLO, we determine the low-energy constants and . In contrast to a pure chiral treatment, the dispersion relation describes the observed curvature of one of the form factors, which we understand as an effect of rescattering beyond NNLO. |
| Experiment Numbers: | |
| Group: | THEORY CENTER |
| Document: | |
| DOI: | http://dx.doi.org/10.1088/1742-6596/800/1/012026 |
| Accepted Manuscript: | Stoffer_2017_J._Phys.__Conf._Ser._800_012026.pdf |
| Supporting Documents: | |
| Supporting Datasets: | |