  I present the effervescent zone model to account for the compact dense
circumstellar material (CSM) around the progenitor of the core collapse
supernova (CCSN) SN 2023ixf. The effervescent zone is composed of bound dense
clumps that are lifted by stellar pulsation and envelope convection to
distances of tens AUs, and then fall back. The dense clumps provide most of the
compact CSM mass and exist alongside the regular (escaping) wind. I crudely
estimate that for a compact CSM within ~30 AU that contains ~0.01 Mo, the
density of each clump is >3000 times the density of the regular wind at the
same radius and that the total volume filling factor of the clumps is several
percent. The clumps might cover only a small fraction of the CCSN photosphere
in the first days post-explosion, accounting for the lack of strong narrow
absorption lines. The long-lived effervescent zone is compatible with no
evidence for outbursts in the years prior to SN 2023ixf explosion and the
large-amplitude pulsations of its progenitor, and it is an alternative to the
CSM scenario of several-years-long high mass loss rate wind.
