Semileptonic decays of heavy mesons with artificial neural networks
paper by Cody M. Grant, Ayesh Gunawardana, and Alexey A Petrov
Project abstract: Experimental checks of the second row unitarity of the Cabibbo-Kobayashi-Maskawa matrix involve extractions of the matrix element $V_{cd}$, which may be obtained from semileptonic decay rates of D to \pi. These decay rates are proportional to hadronic form factors which parameterize how the quark $c \to d$ transition is realized in $D \to \pi$ meson decays. The form factors can not yet be analytically computed over the whole range of available momentum transfer $q^2$, but can be parameterized with a varying degree of model dependency. We propose using artificial neural networks trained from experimental pseudo-data to predict the shape of these form factors with a prescribed uncertainty. We comment on the parameters of several commonly-used model parameterizations of semileptonic form factors. We extract shape parameters and use unitarity to bound the form factor at a given $q^2$, which then allows us to bound the CKM matrix element $|V_{cd}|$.
Graphs and some other relevant files
Other files: ANN structure
Python code for the neural net training (zip file with data): code
Additional questions? Please contact the authors: Cody M. Grant, Ayesh Gunawardana, and Alexey A Petrov