dc.contributor.author | Colombo, D | |
dc.contributor.author | Meidt, SE | |
dc.contributor.author | Schinnerer, E | |
dc.contributor.author | García-Burillo, S | |
dc.contributor.author | Hughes, A | |
dc.contributor.author | Pety, J | |
dc.contributor.author | Leroy, AK | |
dc.contributor.author | Dobbs, CL | |
dc.contributor.author | Dumas, G | |
dc.contributor.author | Thompson, TA | |
dc.contributor.author | Schuster, KF | |
dc.contributor.author | Kramer, C | |
dc.date.accessioned | 2016-06-08T13:04:07Z | |
dc.date.issued | 2014-03-20 | |
dc.description.abstract | The kinematic complexity and the favorable position of M51 on the sky make this galaxy an ideal target to test different theories of spiral arm dynamics. Taking advantage of the new high-resolution PdBI Arcsecond Whirlpool Survey data, we undertake a detailed kinematic study of M51 to characterize and quantify the origin and nature of the non-circular motions. Using a tilted-ring analysis supported by several other archival data sets, we update the estimation of M51's position angle (P.A. = (173 ± 3)°) and inclination (i = (22 ± 5)°). Harmonic decomposition of the high-resolution (∼40 pc) CO velocity field shows the first kinematic evidence of an m = 3 wave in the inner disk of M51 with a corotation at R CR, m = 3 = 1.1 ± 0.1 kpc and a pattern speed of Ωp, m = 3 ≈ 140 km s -1 kpc-1. This mode seems to be excited by the nuclear bar, while the beat frequencies generated by the coupling between the m = 3 mode and the main spiral structure confirm its density-wave nature. We observe also a signature of an m = 1 mode that is likely responsible for the lopsidedness of M51 at small and large radii. We provide a simple method to estimate the radial variation of the amplitude of the spiral perturbation (V sp) attributed to the different modes. The main spiral arm structure has 〈V sp〉 = 50-70 km s-1, while the streaming velocity associated with the m = 1 and m = 3 modes is, in general, two times lower. Our joint analysis of H I and CO velocity fields at low and high spatial resolution reveals that the atomic and molecular gas phases respond differently to the spiral perturbation due to their different vertical distribution and emission morphology. © 2014. The American Astronomical Society. All rights reserved. | en_GB |
dc.description.sponsorship | We thank our anonymous referee for thoughtful comments
that improved the quality of the paper. We thank the IRAM
staff for their support during the observations with the Plateau
de Bure interferometer and the 30 m telescope. D.C. and A.H.
acknowledge funding from the Deutsche Forschungsgemeinschaft
(DFG) via grant SCHI 536/5-1 and SCHI 536/7-1 as
part of the priority program SPP 1573 “ISM-SPP: Physics of the
Interstellar Medium.” C.L.D. acknowledges funding from the
European Research Council for the FP7 ERC starting grant
project LOCALSTAR. T.A.T. acknowledges support from
NASA grant No. NNX10AD01G. During this work, J.P. was
partially funded by the grant ANR-09-BLAN-0231-01 from
the French Agence Nationale de la Recherche as part of the
SCHISM project (http://schism.ens.fr/). E.S., A.H. and D.C.
thank NRAO for their support and hospitality during their visits
in Charlottesville. E.S. thanks the Aspen Center for Physics and
the NSF grant No. 1066293 for hospitality during the development
and writing of this paper. D.C. thanks Glenn van de Ven for
the useful discussion and the help with the harmonic decomposition
code. S.G.B. acknowledges economic support from Junta
de Andalucia grant P08 TIC 03531. The National Radio Astronomy
Observatory is a facility of the National Science Foundation
operated under cooperative agreement by Associated Universities,
Inc. | en_GB |
dc.identifier.citation | Vol. 784: 4 | en_GB |
dc.identifier.doi | 10.1088/0004-637X/784/1/4 | |
dc.identifier.uri | http://hdl.handle.net/10871/21924 | |
dc.language.iso | en | en_GB |
dc.publisher | American Astronomical Society | en_GB |
dc.subject | galaxies | en_GB |
dc.subject | M51 | en_GB |
dc.subject | NGC 5194 | en_GB |
dc.subject | ISM | en_GB |
dc.subject | kinematics | en_GB |
dc.subject | dynamics | en_GB |
dc.subject | spiral | en_GB |
dc.subject | structure | en_GB |
dc.title | The PdBI Arcsecond Whirlpool Survey (PAWS): Multi-phase cold gas kinematic of M51 | en_GB |
dc.type | Article | en_GB |
dc.date.available | 2016-06-08T13:04:07Z | |
dc.identifier.issn | 0004-637X | |
dc.description | This is the final version of the article. Available from the publisher via the DOI in this record. | en_GB |
dc.identifier.journal | Astrophysical Journal | en_GB |