https://doi.org/10.1140/epjc/s10052-015-3322-z
Regular Article - Theoretical Physics
Angular distributions in the radiative decays of the 
state of charmonium originating from polarized 
collisions
1
Department of Physics and Astronomy, Georgia State University, Atlanta, GA, 30303, USA
2
Department of Physics, Hong Kong Baptist University, Kowloon Tong, Hong Kong
* e-mail: cwong14@student.gsu.edu
Received:
26
December
2014
Accepted:
17
February
2015
Published online:
7
March
2015
Using the helicity formalism, we calculate the combined angular distribution function of the two gamma photons (
and 
) and the electron (
) in the triple cascade process 
, when 
and 
are arbitrarily polarized. We also derive six different partially integrated angular distribution functions which give the angular distributions of one or two particles in the final state. Our results show that by measuring the two-particle angular distribution of and and that of and , one can determine the relative magnitudes as well as the relative phases of all the helicity amplitudes in the two charmonium radiative transitions 
and 
.
© SIF and Springer-Verlag Berlin Heidelberg, 2015
