Perhaps you should try some spelling variations:
"particle acceleration" » "particle accelerators"
"particle accelerating" » "particle accelerations", "particles acceleration", "pareticle acceleration"
"particle accelerator" » "particle accelerators"
"particle acceleraton" » "particles acceleration", "particle accelerations", "pareticle acceleration"

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (("particle accelerator") OR ((("particle acceleration") OR ((("particle accelerating") OR ("particle acceleraton")))))).
• Removing quotes may allow a broader search: (( particle accelerator ) or ((( particle acceleration ) or ((( particle accelerating ) or ( particle acceleraton )))))).
• Adding a wildcard symbol may retrieve word variants: (("particle accelerator") or ((("particle acceleration") or ((("particle accelerating") or ("particle acceleraton"))))))*.