- ID:
- ivo://CDS.VizieR/J/A+A/562/A121
- Title:
- ARRAKIS: Atlas of Resonance Rings as Known In S4G
- Short Name:
- J/A+A/562/A121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Resonance rings and pseudorings (here collectively called "rings") are thought to be related to the gathering of material near dynamical resonances caused by non-axisymmetries in galaxy discs. Therefore, they are the consequence of secular evolution processes that redistribute material and angular momentum in discs. Their study may give clues on the formation and growth of bars and other disc non-axisymmetries. Our aims are to produce a Catalogue and an Atlas of the rings detected in the Spitzer Survey of Stellar Structure in Galaxies (S4G) and to conduct a statistical study of the data in the Catalogue. We traced the contours of rings previously identified by Buta et al. (in preparation) and fitted them with ellipses. We found the orientation of bars by studying the galaxy ellipse fits from S4G's Pipeline4. We used the galaxy orientation data obtained by S4G's Pipeline 4 to obtain intrinsic ellipticities and orientations of rings and the bars. ARRAKIS contains data on 724 ringed galaxies in the S4G. The frequency of resonance rings in the S4G is of 16+/-1% and 35+/-1% for outer and inner features, respectively. Outer rings are mostly found in Hubble stages -1<=T<=4. Inner rings are found in a broad distribution that covers the range -1<=T<=7. We confirm that outer rings have two preferred orientations, namely parallel and perpendicular to the bar. We confirm a tendency for inner rings to be oriented parallel to the bar, but we report the existence of a significant fraction (maybe as large as 50%) of inner features that have random orientations with respect to the bar. These misaligned inner rings are mostly found in late-type galaxies (T>=4). We find that the fraction of barred galaxies hosting outer (inner) rings is ~1.7 times (~1.3 times) that in unbarred galaxies. We confirm several results from previous surveys, as well as predictions from simulations of resonant rings and/or from manifold flux tube theory. We report that a significant fraction of inner rings in late-type galaxies have a random orientation with respect to the bar. This may be due to spiral modes decoupled from the bar dominating the Fourier amplitude spectrum at the radius of the inner ring. The fact that rings are only mildly favoured by bars suggests that those in unbarred galaxies either formed due to weak departures from the axisymmetry of the galactic potential or that they are born because of bars that have been destroyed after the ring formation.
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- ID:
- ivo://CDS.VizieR/J/ApJS/96/39
- Title:
- Catalog of Southern Ringed Galaxies
- Short Name:
- J/ApJS/96/39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Catalog of Southern Ringed Galaxies (CSRG) is a comprehensive compilation of diameters, axis ratios, relative bar position angles, and morphologies of inner and outer rings, pseudorings, and lenses in 3692 galaxies south of declination -17{deg}. The purpose of the catalog is to evaluate the idea that these ring phenomena are related to orbital resonances with a bar or oval in galaxy potentials. The catalog is based on visual inspection of most of the 606 fields of the Science Research Council (SRC) IIIa-J southern sky survey, with the ESO-B, ESO-R, and Palomar Sky surveys used as auxiliaries when needed for overexposed core regions. The catalog is most complete for SRC fields 1-303 (mostly south of declination -42{deg}). In addition to ringed galaxies, a list of 859 mostly nonringed galaxies intended for comparison with other catalogs is provided.
- ID:
- ivo://CDS.VizieR/J/A+A/582/A86
- Title:
- Catalogue of features in the S4G
- Short Name:
- J/A+A/582/A86
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalogue of the features for the complete Spitzer Survey of Stellar Structure in Galaxies (S4G), including 2352 nearby galaxies, is presented. The measurements are made using 3.6um images, largely tracing the old stellar population; at this wavelength the effects of dust are also minimal. The measured features are the sizes, ellipticities, and orientations of bars, rings, ringlenses, and lenses. Measured in a similar manner are also barlenses (lens-like structures embedded in the bars), which are not lenses in the usual sense, being rather the more face-on counterparts of the boxy/peanut structures in the edge-on view. In addition, pitch angles of spiral arm segments are measured for those galaxies where they can be reliably traced. More than one pitch angle may appear for a single galaxy. All measurements are made in a human- supervised manner so that attention is paid to each galaxy. We create a catalogue of morphological features in the complete S4G. We used isophotal analysis, unsharp masking, and fitting ellipses to measured structures. We find that the sizes of the inner rings and lenses normalized to barlength correlate with the galaxy mass: the normalized sizes increase toward the less massive galaxies; it has been suggested that this is related to the larger dark matter content in the bar region in these systems. Bars in the low mass galaxies are also less concentrated, likely to be connected to the mass cut-off in the appearance of the nuclear rings and lenses. We also show observational evidence that barlenses indeed form part of the bar, and that a large fraction of the inner lenses in the non-barred galaxies could be former barlenses in which the thin outer bar component has dissolved.
- ID:
- ivo://CDS.VizieR/J/ApJS/181/572
- Title:
- Collisional ring galaxies atlas
- Short Name:
- J/ApJS/181/572
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog and imaging atlas of classical (collisional) RING galaxies distilled from the Arp-Madore Atlas of Southern Peculiar Galaxies and Associations and supplemented with other known RING galaxies from the published literature. The catalog lists the original host object, compiles available redshifts, and presents newly determined positions for the central (target) galaxy and its nearest companion(s). 127 collisional RING systems are illustrated and their components identified. All of the RINGS have plausible colliders identified; many are radial-velocity confirmed companions. Finally, we make note of the existence of a rare subclass of RING galaxies exemplified by AM 2136-492, double/concentric RING galaxies. These objects are predicted by numerical simulations, but they appear to be quite rare and/or short lived in nature.
- ID:
- ivo://CDS.VizieR/J/A+AS/104/1
- Title:
- Faint ring-shaped galaxies near South Pole
- Short Name:
- J/A+AS/104/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A list of probable ring galaxies with a limiting magnitude of 17.5 has been prepared based on visual inspection of the film copies of the J SRC/ESO survey. About 88% of the sample of 125 selected objects seem to be new, hitherto unrecognized as ring galaxies. The candidate objects have been classified following the ring structure and the nucleus appearance.
- ID:
- ivo://CDS.VizieR/J/A+A/319/401
- Title:
- HI survey of polar ring galaxies. II.
- Short Name:
- J/A+A/319/401
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a neutral hydrogen survey conducted with the 100-m radiotelescope at Effelsberg of 44 northern objects in the polar-ring galaxy atlas of Whitmore et al. (1990AJ....100.1489W). These observations were performed to complement the Green Bank observations of polar-ring galaxies (Paper I, 1994AJ....107...99R). We detected 29 of these above our detection limit of a few mJy. The relative content of neutral hydrogen (M_HI_/L_B_) of the early-type galaxies (E, S0) in this sample is significantly higher than for galaxies of the same morphological types from comparison samples, i.e. for elliptical galaxies M_HI_/L_B_=0.17+/-0.09 and for S0 galaxies M_HI_/L_B_=0.75+/-0.13 which is about 6 times the mean value from the comparison samples for the same morphological types.
- ID:
- ivo://CDS.VizieR/J/A+A/386/140
- Title:
- HI survey of polar ring galaxies. IV.
- Short Name:
- J/A+A/386/140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A total of 33 polar ring galaxies and polar ring galaxy candidates were observed in the 21-cm HI line with the 64-m Parkes radio telescope. The objects, selected by their optical morphology, are all south of declination -39{deg} and in only 5 of them had been reported previously. HI line emission was detected towards 18 objects, though in 3 cases the detection may be confused by another galaxy in the telescope beam, and one is a marginal detection. Eight objects were detected for the first time in HI, of which 5 did not have previously known redshifts.
- ID:
- ivo://CDS.VizieR/J/A+A/555/L4
- Title:
- Inner rings in disc galaxies from UV + H{alpha}
- Short Name:
- J/A+A/555/L4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this Letter, I distinguish "passive" inner rings to be those with no current star formation, as distinct from "active" inner rings which have undergone recent star formation. I built a sample of nearby galaxies with inner rings observed in the near- and mid-infrared by the NIRS0S and the S^4^G surveys. I used archival far-ultraviolet (FUV) and H{alpha} imaging of 319 galaxies to diagnose whether their inner rings are passive or active. I found that passive rings are found only in early-type disc galaxies (-3<=T<=2). In this range of stages, 21+/-3% and 28+/-5% of rings are passive according to the FUV and H{alpha} indicators, respectively. A ring which is passive according to FUV is always passive according to H{alpha}, but the reverse is not always true. Ring-lenses form 30-40% of passive rings, which is four times more than the fraction of ring-lenses found in active rings in the stage range -3<=T<=2. This is consistent with both a resonance and a manifold origin for the rings because both models predict purely stellar rings to be wider than their star-forming counterparts. In the case of resonance rings, the widening may be at least partly due to the dissolution of rings. If most inner rings have a resonance origin, I estimate 200Myr to be a lower bound for their dissolution time-scale. This time-scale is on the order of one orbital period at the radius of inner rings.
- ID:
- ivo://CDS.VizieR/J/A+AS/129/357
- Title:
- Morphology of peculiar ring galaxies
- Short Name:
- J/A+AS/129/357
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It is proposed that Peculiar Ring Galaxies can be divided into five principal types according to the morphology of the ring and bulge, based on the visual inspection of 489 selected object. Those objects have been named "peculiar" following the "Catalogue of Southern Peculiar Galaxies and Associations" by Arp & Madore (1986, Cat. <VII/170>).
- ID:
- ivo://CDS.VizieR/J/A+A/330/881
- Title:
- Radial velocities of Cartwheel Galaxy
- Short Name:
- J/A+A/330/881
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on high spectral and spatial resolution kinematic observations of H{alpha} emission from the Cartwheel system obtained with a scanning Fabry-Perot interferometer. Velocity fields for two galaxies were measured, for the main galaxy of the system, the Cartwheel galaxy, and for a spiral companion ~25h^-1^kpc to the north. The velocity field and the rotation curve of the spiral companion shows classical differential rotation and indicates the mass of the galaxy to be in the range 2.9-4.8x10^9^M{sun}. The Cartwheel galaxy contains strong H{alpha} in emission asymmetrically distributed along its outer ring, with some faint emission detected inside it. The velocity field and the rotation curve of the Cartwheel galaxy is clearly dominated by differential rotation although second-order effects cause distortions which can be understood in a scenario where expansion and density-wave motions are also considered. Our best model-fit to the observed velocity field of the Cartwheel galaxy includes three components for the kinematic of its outer ring: a circular velocity of 217km/s, an expansion velocity of 13-30+/-10km/s and a sinusoidal perturbation with an amplitude of 20+/-5km/s. This expansion velocity, lower than found in previous studies, implies that the ring could be older than previously thought. The rotation curve of the Cartwheel galaxy is consistent with a progenitor which had the morphology of a late-type spiral galaxy. Our measurements support the collisional models of ring galaxy formation and should impose strong constraints to simulations.
