Open AccessLate‐type galaxies observed with SAURON: two‐dimensional stellar and emission‐line kinematics of 18 spirals
Author(s) -
Ganda Katia,
FalcónBarroso Jesús,
Peletier Reynier F.,
Cappellari Michele,
Emsellem Eric,
McDermid Richard M.,
Tim de Zeeuw P.,
Carollo C. Marcella
Publication year - 2006
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2005.09977.x
Subject(s) - physics , astrophysics , stellar kinematics , velocity dispersion , galaxy , bulge , doubly ionized oxygen , william herschel telescope , spiral galaxy , astronomy , star formation , elliptical galaxy , emission spectrum , luminous infrared galaxy , spectrograph , spectral line , milky way
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, Mg b absorption features and the emission in the Hβ line and the [O iii ]λλ4959, 5007 Å and [N i ]λλ5198, 5200 Å doublets over a 33 × 41‐arcsec 2 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.