There is a new alien vessel research tree on the way where capturing any intact alien craft will allow you to research "Alien Ship Theory" and then go on to be able to research any alien vessel you capture. Unfortunately not in 2.2 though there may be a patch / add-on to install it in 2.2.
I think to research particle beams you need to have researched the particle beam rifle and maybe the blaster as well before you can study the vessel sized one. There is also a research project directly on the particle accelerator cartridges that may be needed first.
The Wiki lists most of the research projects and at the bottom tells what research project needs to be finished to be able to start on the one you are reading.
Brett