High resolution NaI and CaII absorption observations towards M13, M15
  and M33
  We present high resolution (R = 60,000) measurements of the NaI D1 and D2
(5890 A) and CaII K (3933 A) interstellar absorption line profiles recorded
towards several post-AGB stars located within the M13 and M15 globular
clusters, supplemented with a lower resolution spectrum of the CaII K-line
observed in absorption towards an Ofpe/WN9 star in the central region of the
M33 galaxy. The normalized interstellar absorption profiles have been fit with
cloud component velocities, doppler widths and column densities in order to
investigate the kinematics and physical conditions of the neutral and partially
ionized gas observed along each sight-line. Our CaII observations towards M13
have revealed 4 absorption components that can be identified with galactic
Intermediate Velocity Clouds (IVCs) spanning the -50 > Vlsr > -80 km/s range.
The NaI/CaII ratio for these IVC's is<0.3, which characterizes the gas as being
warm (T=1000 K) and partially ionized. Similar observations towards two stars
within M15 have revealed absorption due to a galactic IVC at Vlsr=+65 km/s.
This IVC is revealed to have considerable velocity structure, requiring at
least 3 cloud components to fit the observed NaI and CaII profiles. CaII K-line
observations of a sight-line towards the center of the M33 galaxy have revealed
at least 10 cloud components. A cloud at Vlsr=-130 km/s is either an IVC
associated with the M33 galaxy occurring at +45 km/s with respect to the M33
local standard of rest, or it is a newly discovered HVC associated with our own
Galaxy. In addition, 4 clouds have been discovered in the -165 > Vlsr > -205
km/s range. Three of these clouds are identified with the disk gas of M33,
whereas a component at - 203 km/s could be IVC gas in the surrounding halo of
M33.
