High-Resolution Na I and Ca II Absorption Observations toward M13, M15, and M33

International audienceWe present high resolution (R = 60000) measurements of the Na I D1 & D2 (5890 ) and Ca II K (3933 ) interstellar absorption line profiles recorded toward several post-AGB stars located within the M13 and M15 globular clusters, supplemented with a lower resolution spectrum of the Ca II K-line observed in absorption toward 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