Eb  |--------------------------------------------------------------|
Bb  |--------------------------------------------------------------|
Gb  |-s13-11-9--------------------------9h11r9-----9---------------|
Db  |-----------------9h11-11-9------------------11---11-9---------|
Ab  |---------------------------11-9-11----------------------------|
eb  |--------------------------------------------------------------|


What does the R mean?
I dont think its pull off as there is another in the tab which is labled with an P.
Well the symbols used in tabs aren't exactly universal. You'll often find yourself taking a best guess.

In this case, I think r means 'release', so yeah, a pull-off from the 11th fret you just hammered onto.