Instead of ls, could you use something like:
find \ -name '*.?1@$*' -print
to see what they are in the first place, then use this listing (once you're satisfied that they aren't required!) to rm them, possibly like:
find \ -name '*.?1@$*' -exec rm {} \;
Be very careful, particularly executing an rm in the root directory! Are you aware what is causing these files to be produced, as it looks like something that needs sorting out.
HTH.