Diagnostics of a Nuclear Starburst: Water and Methanol Masers
  We test models of starburst driven outflows using observations of the 22.2
GHz H$_2$O and 36.2 GHz class I CH$_3$OH maser lines. We have observed the
starburst galaxy NGC 253 using the Karl G. Jansky Very Large Array. We present
evidence for entrainment of star-forming dense-molecular gas in the outflow of
NGC 253. We also show that H$_2$O masers are associated with forming super star
clusters and not with supernova remnants. We detect four new 36 GHz CH$_3$OH
masers in the central kpc and show possible evidence for a star-formation
origin of two class I CH$_3$OH masers. Such high resolution observations are
essential for understanding the origin of these masers.
