https://doi.org/10.1140/epja/i2018-12539-9
Regular Article - Theoretical Physics
Differential technique for the covariant orbital angular momentum operators
1
National Research Centre “Kurchatov Institute”: Petersburg Nuclear Physics Institute, RU-188300, Gatchina, Russia
2
Helmholtz-Institut für Strahlen- und Kernphysik der Universität Bonn, Nußallee 14-16, D-53115, Bonn, Germany
* e-mail: cyrstsh@gmail.com
Received:
22
February
2018
Accepted:
15
May
2018
Published online:
26
June
2018
The orbital angular momentum operator expansion turns out to be a powerful tool to construct the fully covariant partial wave amplitudes of hadron decay reactions and hadron photo- and electroproduction processes. In this paper we consider a useful development of the orbital angular momentum operator expansion method. We present the differential technique allowing the direct calculation of convolutions of two orbital angular momentum operators with an arbitrary number of open Lorentz indices. This differential technique greatly simplifies calculations when the reaction subject to the partial wave analysis involves high spin particles in the initial and/or final states. We also present a useful generalization of the orbital angular momentum operators.
© SIF, Springer-Verlag GmbH Germany, part of Springer Nature, 2018
