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  • Late-type galaxies observed...
    Ganda, Katia; Falcón-Barroso, Jesús; Peletier, Reynier F.; Cappellari, Michele; Emsellem, Eric; McDermid, Richard M.; Tim de Zeeuw, P.; Carollo, C. Marcella

    Monthly notices of the Royal Astronomical Society, March 2006, Letnik: 367, Številka: 1
    Journal Article

    We present the stellar and gas kinematics of a sample of 18 nearby late-type spiral galaxies (Hubble types ranging from Sb to Sd), observed with the integral-field spectrograph SAURON at the 4.2-m William Herschel Telescope. SAURON covers the spectral range 4800–5380 Å, allowing us to measure the Hβ, Fe, Mgb absorption features and the emission in the Hβ line and the O iiiλλ4959, 5007 Å and N iλλ5198, 5200 Å doublets over a 33 × 41-arcsec2 field of view. The maps cover the nuclear region of these late-type galaxies and in all cases include the entire bulge. In many cases the stellar kinematics suggests the presence of a cold inner region, as visible from a central drop in the stellar velocity dispersion. The ionized gas is almost ubiquitous and behaves in a complicated fashion: the gas velocity fields often display more features than the stellar ones, including wiggles in the zero-velocity lines, irregular distributions, ring-like structures. The line ratio O iii/Hβ often takes on low values over most of the field, probably indicating a wide-spread star formation.