The PdBI Arcsecond Whirlpool Survey (PAWS): Multi-phase Cold Gas Kinematic of M51

摘要: The kinematic complexity and the favorable position of M51 on sky make this galaxy an ideal target to test different theories spiral arm dynamics. Taking advantage new high-resolution PdBI Arcsecond Whirlpool Survey data, we undertake a detailed study characterize quantify origin nature non-circular motions. Using tilted-ring analysis supported by several other archival data sets, update estimation M51's angle (P.A. = (173 ± 3)°) inclination (i (22 5)°). Harmonic decomposition (~40 pc) CO velocity field shows first evidence m 3 wave in inner disk with corotation at R CR, 1.1 0.1 kpc pattern speed Ω p, ≈ 140 km s-1 kpc-1. This mode seems be excited nuclear bar, while beat frequencies generated coupling between main structure confirm its density-wave nature. We observe also signature 1 that is likely responsible for lopsidedness small large radii. provide simple method estimate radial variation amplitude perturbation (V sp) attributed modes. has langV sprang 50-70 s-1, streaming associated modes is, general, two times lower. Our joint H I fields low high spatial resolution reveals atomic molecular gas phases respond differently due their vertical distribution emission morphology. Based observations carried out IRAM Plateau de Bure Interferometer 30 telescope. operated INSY/CNRS (France), MPG (Germany), IGN (Spain).