subroutine kget_beam_momentum(p4)
*
* begin_doc
*
*  Returns the 4-momentum of the center of mass system.
*
*  Input Parameters:
*  None
*
*  Output Parameters:
*  p4(4)          double precision array
*                 (px,py,pz,E) of center of mass returned to caller
*
*  Other routines:
*
*  Notes:
*
*  Author:   Paul Avery      Created:  Fri Sep  5 14:06:40 EDT 1997
*
*  Major revisions:
*
*
* end_doc