- ID:
- ivo://CDS.VizieR/J/AJ/110/1699
- Title:
- F-P observations of globular clusters
- Short Name:
- J/AJ/110/1699
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the Rutgers Imaging Fabry-Perot Spectrophotometer on the CTIO 4-m telescope, we have measured radial velocities for 548 stars in 47 Tuc (NGC 104), 128 stars in NGC 6397, and 132 stars in M30 (NGC 7099), with uncertainties between 0.5 and 5km/s. In 47 Tuc and NGC 6397, the dispersion profiles at first increase with decreasing radii but then flatten in the central 0.4'. This is the same behavior seen in our previously published profile for M15. The measured stellar velocities show that 47 Tuc is rotating, with a projected rotation axis that is aligned with the isophotal minor axis. We also find a similar alignment for the rotation that we previously measured in M15. A map of the average velocity in the central regions derived from the integrated light shows rotation for NGC 6397 and 47 Tuc. For 47 Tuc, NGC 6397, and M15, the amplitude of the projected rotation measured at a radius of 0.6' using the individual stellar velocities is equal to, or smaller than, that measured at a radius of 0.2' using the integrated light. This is not consistent with the solid-body rotation usually assumed for the inner regions. To study further the form of the projected rotation we have used two-dimensional spline smoothing to derive a mean velocity map for 47 Tuc using the individual stellar velocities. This map shows that the projected rotation velocity reaches a plateau at a radius of 3' and that the radial dependence of the projected rotation velocity deviates significantly from solid body beyond 2'. We have repeat measurements of the two "high-velocity" stars of Meylan, Dubath, and Mayor. However, we detect more stars with similar large offsets from the cluster mean velocity. The number of stars that we measure with large velocity offsets is consistent with a normal distribution, so that there is no need to invoke a special creation mechanism for these stars.
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- ID:
- ivo://CDS.VizieR/J/A+A/633/A147
- Title:
- FQS. Galactic Plane CO survey
- Short Name:
- J/A+A/633/A147
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Forgotten Quadrant Survey (FQS), an ESO large project that used the 12m antenna of the Arizona Radio Observatory to map the Galactic Plane in the range 220{deg}<l<240{deg}, and -2.5{deg}<b<0{deg}, both in ^12^CO(1-0), and ^13^CO(1-0), at a spectral resolution of 0.65km/s and 0.26km/s. We used the (1-0) transition of carbon monoxide to trace the molecular component of the interstellar medium. Our data set allows us to easily identify how the molecular dense gas is organised at different spatial scales: from the giant clouds with their denser filamentary networks, down to the clumps and cores that host the new-born stars and to obtain reliable estimates of their key physical parameters such as size and mass. We present the first release of the data of the FQS survey and discuss their quality. Spectra with 0.65km/s velocity channels have noise ranging from 0.8K to 1.3K for ^12^CO (1-0) and from 0.3K to 0.6K for ^13^CO (1-0). In this first paper, we used the ^12^CO (1-0) spectral cubes to produce a catalogue of 263 molecular clouds. The clouds are grouped in three main structures corresponding to the Local, Perseus, and Outer arms up to a distance of ~8.6kpc from the Sun. This is the first self-consistent statistical catalogue of molecular clouds of the outer Galaxy obtained with a subarcminute spatial resolution and therefore able to detect not only the classical giant molecular clouds, but also the small clouds and to resolve the cloud structure at the sub-parsec scale up to a distance of a few kiloparsec. We found two classes of objects: structures with sizes above a few parsecs that are typical molecular clouds and may be self-gravitating, and subparsec structures that cannot be in gravitational equilibrium and are likely transient or confined by external pressure. We used the ratio between the Herschel H2 column density and the integrated intensity of the CO lines to calculate the CO conversion factor and we found mean values of (3.3+/-1.4)x10^20^cm^-2^/(K.km/s) and (1.2+/-0.4)x10^21^cm^-2^/(K.km/s), for ^12^CO (1-0) and ^13^CO (1-0), respectively. FQS contributes to the general effort in producing a new generation of high-quality spectroscopic data for the Galactic Plane in the less studied third Galactic Quadrant, toward the outer Galaxy. FQS has produced a data-set of great legacy value, largely improving the data quality both in terms of sensitivity and spatial resolution over previous data sets.
- ID:
- ivo://CDS.VizieR/J/MNRAS/490/2521
- Title:
- Fractal Statistics in Young Star Clusters
- Short Name:
- J/MNRAS/490/2521
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used fractal statistics to quantify the degree of observed substructures in a sample of 50 embedded clusters and more evolved open clusters (<100Myr) found in different galactic regions. The observed fractal parameters were compared with N-body simulations from the literature, which reproduce star-forming regions under different initial conditions and geometries that are related to the cluster' dynamical evolution. Parallax and proper motion from Gaia-DR2 were used to accurately determine cluster membership by using the Bayesian model and cross-entropy technique. The statistical parameters Q, <m> and <s> were used to compare observed cluster structure with simulations. A low level of substructures (Q<0.8) is found for most of the sample that coincides with simulations of regions showing fractal dimension D~2-3. Few clusters (<20 per cent) have uniform distribution with a radial density profile ({alpha}<2). A comparison of Q with mass segregation ({LAMBDA}MSR) and local density as a function of mass ({SIGMA}LDR) shows the clusters coinciding with models that adopt supervirial initial conditions. The age-crossing time plot indicates that our objects are dynamically young, similar to the unbound associations found in the Milky Way. We conclude that this sample may be expanding very slowly. The flat distribution in the Q-age plot and the absence of trends in the distributions of {LAMBDA}MSR and {SIGMA}LDR against age show that in the first 10 Myr the clusters did not change structurally and seem not to have expanded from a much denser region.
- ID:
- ivo://CDS.VizieR/J/A+A/618/A147
- Title:
- Fraction of bulge metal poor & metal rich stars
- Short Name:
- J/A+A/618/A147
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent spectroscopic surveys of the Galactic bulge have unambiguously shown that the bulge contains two main components, which are best separated by their iron content, but also differ in spatial distribution, kinematics, and abundance ratios. The so-called metal poor component peaks at [Fe/H]~-0.4, while the metal rich component peaks at [Fe/H]~+0.3. The total metallicity distribution function is therefore bimodal with a dip at [Fe/H]~0. The relative fraction of the two components changes significantly across the bulge area. We provide, for the first time, the fractional contribution of the metal poor and metal rich stars to the stellar mass budget of the Galactic bulge and its variation across the bulge area. This result follows from the combination of the stellar mass profile obtained empirically, by our group, from VISTA Variables in the Via Lactea data, with the relative fraction of metal poor and metal rich stars, across the bulge area, derived from the GIRAFFE Inner Bulge spectroscopic Survey. We find that metal poor stars make up 48% of the total stellar mass of the bulge, within the region |l|<10, |b|<9.5 and that the remaining 52% are made up of metal rich stars. The latter dominate the mass budget at intermediate latitudes |b|~4, but become marginal in the outer bulge (|b|>8). The metal poor component is more axisymmetric than the metal rich component, and it is at least comparable and possibly slightly dominant in the inner few degrees. As a result, the metal poor component, which does not follow the main bar, is not marginal in terms of the total mass budget as previously thought, and this new observational evidence must be included in bulge models. While the trend of the total radial velocity dispersion follows the total stellar mass, when we examine the velocity dispersion of each component individually, we find that metal poor stars have higher velocity dispersion where they make up a smaller fraction of the stellar mass, and vice versa. This is due to the kinematical and spatial distribution of the two metallicity components being significantly different, as already discussed in the literature.
- ID:
- ivo://CDS.VizieR/J/AJ/134/1133
- Title:
- Fraction of contact binary trojan asteroids
- Short Name:
- J/AJ/134/1133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an optical light-curve survey of 114 Jovian Trojan asteroids conducted to determine the fraction of contact binaries. Sparse sampling was used to assess the photometric range of the asteroids, and those showing the largest ranges were targeted for detailed follow-up observations. This survey led to the discovery of two Trojan asteroids, (17365) and (29314), displaying large light-curve ranges (~1mag) and long rotation periods (<2rotations/day) consistent with a contact binary nature.
- ID:
- ivo://CDS.VizieR/J/ApJ/827/L25
- Title:
- Fractions of quiescent galaxies evolution
- Short Name:
- J/ApJ/827/L25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the UltraVISTA DR1 and 3D-HST catalogs, we construct a stellar-mass-complete sample, unique for its combination of surveyed volume and depth, to study the evolution of the fractions of quiescent galaxies, moderately unobscured star-forming galaxies, and dusty star-forming galaxies as a function of stellar mass over the redshift interval 0.2<=z<=3.0. We show that the role of dusty star-forming galaxies within the overall galaxy population becomes more important with increasing stellar mass and grows rapidly with increasing redshift. Specifically, dusty star-forming galaxies dominate the galaxy population with log(M_star_/M_{sun}_)>~10.3 at z>~2. The ratio of dusty and non-dusty star-forming galaxies as a function of stellar mass changes little with redshift. Dusty star-forming galaxies dominate the star-forming population at log(M_star_/M_{sun}_)>~10.0-10.5, being a factor of ~3-5 more common, while unobscured star-forming galaxies dominate at log(M_star_/M_{sun}_)<~10. At log(M_star_/M_{sun}_)>10.5, red galaxies dominate the galaxy population at all redshift z<3, either because they are quiescent (at late times) or dusty star-forming (in the early universe).
- ID:
- ivo://CDS.VizieR/J/MNRAS/456/2041
- Title:
- Fragmentation in filamentary molecular clouds
- Short Name:
- J/MNRAS/456/2041
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent surveys of dust continuum emission at sub-mm wavelengths have shown that filamentary molecular clouds are ubiquitous along the Galactic plane. These structures are inhomogeneous, with overdensities that are sometimes associated with infrared emission and active of star formation. To investigate the connection between filaments and star formation, requires an understanding of the processes that lead to the fragmentation of filaments and a determination of the physical properties of the overdensities (clumps). In this paper, we present a multiwavelength study of five filamentary molecular clouds, containing several clumps in different evolutionary stages of star formation. We analyse the fragmentation of the filaments and derive the physical properties of their clumps. We find that the clumps in all filaments have a characteristic spacing consistent with the prediction of the 'sausage' instability theory, regardless of the complex morphology of the filaments or their evolutionary stage. We also find that most clumps have sufficient mass and density to form high-mass stars, supporting the idea that high-mass stars and clusters form within filaments.
- ID:
- ivo://CDS.VizieR/J/other/PASA/33.45
- Title:
- FRBCAT: The Fast Radio Burst (FRB) Catalog
- Short Name:
- J/other/PASA/33.
- Date:
- 06 Dec 2021 20:29:39
- Publisher:
- CDS
- Description:
- Here, we present a catalogue of known Fast Radio Burst sources in the form of an online catalogue, FRBCAT. The catalogue includes information about the instrumentation used for the observations for each detected burst, the measured quantities from each observation, and model-dependent quantities derived from observed quantities. To aid in consistent comparisons of burst properties such as width and signal-to-noise ratios, we have re-processed all the bursts for which we have access to the raw data, with software which we make available. The originally derived properties are also listed for comparison.
- ID:
- ivo://CDS.VizieR/J/A+A/609/A1
- Title:
- FR0CAT. a FIRST catalog of FR 0 radio galaxies
- Short Name:
- J/A+A/609/A1
- Date:
- 04 Jan 2022 14:18:36
- Publisher:
- CDS
- Description:
- With the aim of exploring the properties of the class of FR 0 radio galaxies, we selected a sample of 108 compact radio sources, called FR0CAT, by combining observations from the NVSS, FIRST, and SDSS surveys. We included in the catalog sources with redshift <=0.05, with a radio size <=5kpc, and with an optical spectrum characteristic of low-excitation galaxies. Their radio luminosities at 1.4GHz are in the range 10^38^<={nu}L_1.4_<=10^40^erg/s. The FR0CAT hosts are mostly (86%) luminous (-21>=M_r_>=-23) red early-type galaxies with black hole masses 10^8^<=M_BH_<=10^9^M_{sun}_. These properties are similar to those seen for the hosts of FR I radio galaxies, but they are on average a factor ~1.6 less massive. The number density of FR0CAT sources is ~5 times higher than that of FR Is, and thus they represent the dominant population of radio sources in the local Universe. Different scenarios are considered to account for the smaller sizes and larger abundance of FR 0s with respect to FR Is. An age-size scenario that considers FR 0s as young radio galaxies that will all eventually evolve into extended radio sources cannot be reconciled with the large space density of FR 0s. However, the radio activity recurrence, with the duration of the active phase covering a wide range of values and with short active periods strongly favored with respect to longer ones, might account for their large density number. Alternatively, the jet properties of FR 0s might be intrinsically different from those of the FR Is, the former class having lower bulk Lorentz factors, possibly due to lower black hole spins. Our study indicates that FR 0s and FR I/IIs can be interpreted as two extremes of a continuous population of radio sources that is characterized by a broad distribution of sizes and luminosities of their extended radio emission, but shares a single class of host galaxies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/683
- Title:
- Free-form lensing grid solution for A1689
- Short Name:
- J/MNRAS/446/683
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine Abell 1689 non-parametrically, combining strongly lensed Hubble Space Telescope images and weak distortions from wider field Subaru imaging. Our model incorporates member galaxies to improve the lens solution. By adding luminosity-scaled member galaxy deflections to our smooth grid, we can derive meaningful solutions with sufficient accuracy to permit the identification of our own strongly lensed images, so our model becomes self-consistent. We identify 11 new multiply lensed system candidates and clarify previously ambiguous cases, in the deepest optical and near-infrared data to date from Hubble and Subaru. Our improved spatial resolution brings up new features not seen when the weak and strong lensing effects are used separately, including clumps and filamentary dark matter around the main halo. Our treatment means we can obtain an objective mass ratio between the cluster and galaxy components. We find a typical mass-to-light ratios of M/L_B_=21+/-14 inside the r<1arcmin region. Our model independence means we can objectively evaluate the competitiveness of stacking cluster lenses for defining the geometric lensing-distance-redshift relation in a model-independent way.