Differences between CO- and calcium triplet-derived velocity dispersions in spiral galaxies: evidence for central star formation?
Author | dc.contributor.author | Riffel, Rogemar A. | |
Author | dc.contributor.author | Ho, Luis | |
Author | dc.contributor.author | Mason, Rachel | |
Author | dc.contributor.author | Rodríguez Ardila, Alberto | |
Author | dc.contributor.author | Martins, Lucimara | |
Author | dc.contributor.author | Riffel, Rogerio | |
Author | dc.contributor.author | Diaz, Ruben | |
Author | dc.contributor.author | Colina, Luis | |
Author | dc.contributor.author | Alonso-Herrero, Almudena | |
Author | dc.contributor.author | Flohic, Helene | |
Author | dc.contributor.author | González, Omaira | |
Author | dc.contributor.author | Lira Teillery, Paulina | |
Author | dc.contributor.author | McDermid, Richard | |
Author | dc.contributor.author | Ramos Almeida, Cristina | |
Author | dc.contributor.author | Schiavon, Ricardo | |
Author | dc.contributor.author | Thanjavur, Karun | |
Author | dc.contributor.author | Ruschel-Dutra, Daniel | |
Author | dc.contributor.author | Winge, Claudia | |
Author | dc.contributor.author | Perlman, Eric | |
Admission date | dc.date.accessioned | 2015-05-20T19:36:36Z | |
Available date | dc.date.available | 2015-05-20T19:36:36Z | |
Publication date | dc.date.issued | 2015 | |
Cita de ítem | dc.identifier.citation | MNRAS 446, 2823–2836 (2015) | en_US |
Identifier | dc.identifier.other | doi:10.1093/mnras/stu2256 | |
Identifier | dc.identifier.uri | https://repositorio.uchile.cl/handle/2250/130657 | |
General note | dc.description | Artículo de publicación ISI | en_US |
Abstract | dc.description.abstract | We examine the stellar velocity dispersions (σ) of a sample of 48 galaxies, 35 of which are spirals, from the Palomar nearby galaxy survey. It is known that for ultra-luminous infrared galaxies (ULIRGs) and merger remnants, the σ derived from the near-infrared CO band heads is smaller than that measured from optical lines, while no discrepancy between these measurements is found for early-type galaxies. No such studies are available for spiral galaxies – the subject of this paper. We used cross-dispersed spectroscopic data obtained with the Gemini Near-Infrared Spectrograph, with spectral coverage from 0.85 to 2.5 µm, to obtain σ measurements from the 2.29 µm CO band heads (σ CO) and the 0.85 µm calcium triplet (σ CaT). For the spiral galaxies in the sample, we found that σ CO is smaller than σ CaT, with a mean fractional difference of 14.3 per cent. The best fit to the data is given by σopt = (46.0 ± 18.1) + (0.85 ± 0.12)σ CO. This ‘σ-discrepancy’ may be related to the presence of warm dust, as suggested by a slight correlation between the discrepancy and the infrared luminosity. This is consistent with studies that have found no σ-discrepancy in dust-poor early-type galaxies, and a much larger discrepancy in dusty merger remnants and ULIRGs. That σ CO is lower than σopt may also indicate the presence of a dynamically cold stellar population component. This would agree with the spatial correspondence between low-σ CO and young/intermediate-age stellar populations that has been observed in spatially resolved spectroscopy of a handful of galaxies. | en_US |
Lenguage | dc.language.iso | en | en_US |
Publisher | dc.publisher | Royal Astronomical Society | en_US |
Type of license | dc.rights | Atribución-NoComercial-SinDerivadas 3.0 Chile | * |
Link to License | dc.rights.uri | http://creativecommons.org/licenses/by-nc-nd/3.0/cl/ | * |
Keywords | dc.subject | galaxies: active | en_US |
Keywords | dc.subject | galaxies: kinematics and dynamics | en_US |
Keywords | dc.subject | galaxies: star formation | en_US |
Keywords | dc.subject | infrared: galaxies | en_US |
Título | dc.title | Differences between CO- and calcium triplet-derived velocity dispersions in spiral galaxies: evidence for central star formation? | en_US |
Document type | dc.type | Artículo de revista |
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