- ID:
- ivo://CDS.VizieR/J/MNRAS/397/1756
- Title:
- Fourier-derived parameters of the CIG sample
- Short Name:
- J/MNRAS/397/1756
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present here the results of a Fourier photometric decomposition of a representative sample of ~100 isolated CIG galaxies (Catalog of Isolated Galaxies) in the morphological range Sb-Sc. This study is an integral part of the AMIGA (Analysis of the Interstellar Medium of Isolated Galaxies) project. It complements the photometric analysis presented in our previous paper for the same sample of disc galaxies by allowing a description of the spiral structure morphology. We also estimate dynamical measures like torque strength for bar and spiral, and also the total non-axisymmetric torque by assuming a constant mass-to-light ratio, and explore the interplay between the spiral and bar components of galaxies. Both the length (l_bar_) and the contrast (e.g. A_2b_) of the Fourier bars decrease along the morphological sequence Sb-Sbc-Sc, with bars in earlier types being longer and showing higher contrast. The bars of Sb galaxies are ~ three times longer than the bars in Sc types, consistent with our previous study. We find that the longer bars are not necessarily stronger (as quantified by the torque Q_b_measure), but longer bars show a higher contrast A_2b_, in very good agreement with theoretical predictions. Our data suggest that bar and spiral components are rather independent in the sense that the torque strengths of the two components are not correlated. The total strength Q_g_ is a very reliable tracer of the bar strength measure Q_b_, the two quantities showing a very tight linear correlation. Comparison with a similar sample of disc galaxies (same morphological range) extracted from the OSUBGS (Ohio State University Bright Galaxy Survey) indicates that the isolated CIG/AMIGA galaxies host significantly longer Fourier bars and possibly show a different distribution of spiral torque Q_s_. The Fourier analysis also revealed a potential case of counterwinding spiral structure (KIG652/NGC5768), which deserves further kinematic study. We find that m=2 (i.e. dominating two-armed pattern) is the most common spiral arm multiplicity among the sample of Sb-Sc CIG/AMIGA galaxies (~40 per cent), m=2 and 3 and m=1 and 2 are found in ~28 and ~13 per cent of isolated galaxies, respectively.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/369/723
- Title:
- Fourier parameters for Cepheid variables
- Short Name:
- J/MNRAS/369/723
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The superb phase resolution and quality of the OGLE data on LMC and SMC Cepheids, together with existing data on Galactic Cepheids, are combined to study the period-colour (PC) and amplitude-colour (AC) relations as a function of pulsation phase. Our results confirm earlier work that the LMC PC relation (at mean light) is more consistent with two lines of differing slopes, separated at a period of 10 days. However, our multi-phase PC relations reveal much new structure which can potentially increase our understanding of Cepheid variables. These multi-phase PC relations provide insight into why the Galactic PC relation is linear but the LMC PC relation is non-linear. This is because the LMC PC relation is shallower for short (logP<1) and steeper for long (logP>1) period Cepheids than the corresponding Galactic PC relation. Both of the short and long period Cepheids in all three galaxies exhibit the steepest and shallowest slopes at phases around 0.75-0.85, respectively. A consequence is that the PC relation at phase ~0.8 is highly non-linear. Further, the Galactic and LMC Cepheids with logP>1 display a flat slope in the PC plane at phases close to the maximum light. When the LMC period- luminosity (PL) relation is studied as a function of phase, we confirm that it changes with the PC relation. The LMC PL relation in V- and I-band near the phase of 0.8 provides compelling evidence that this relation is also consistent with two lines of differing slopes joined at a period close to 10 days.
- ID:
- ivo://CDS.VizieR/J/AJ/156/140
- Title:
- Four new eclipsing mid M-dwarf systems from MEarth
- Short Name:
- J/AJ/156/140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using data from the MEarth-North and MEarth-South transit surveys, we present the detection of eclipses in four mid M-dwarf systems: LP 107-25, LP 261-75, LP 796-24, and LP 991-15. Combining the MEarth photometry with spectroscopic follow-up observations, we show that LP 107-25 and LP 796-24 are short-period (1.388 and 0.523 day, respectively) eclipsing binaries in triple-lined systems with substantial third-light contamination from distant companions. LP 261-75 is a short-period (1.882 day) single-lined system consisting of a mid M-dwarf eclipsed by a probable brown dwarf secondary, with another distant visual brown dwarf companion. LP 991-15 is a long-period (29.3 day) double-lined eclipsing binary on an eccentric orbit with a geometry that produces only primary eclipses. A spectroscopic orbit is given for LP 991-15, and initial orbits for LP 107-25 and LP 261-75.
- ID:
- ivo://CDS.VizieR/J/A+A/510/A100
- Title:
- Four new SDSS eclipsing systems
- Short Name:
- J/A+A/510/A100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometry of nine cataclysmic variable stars identified by the Sloan Digital Sky Survey, aimed at measuring the orbital periods of these systems. Four of these objects show deep eclipses, from which we measure their orbital periods. The light curves of three of the eclipsing systems are also analysed using the LCURVE code, and their mass ratios and orbital inclinations determined. SDSS J075059.97+141150.1 has an orbital period of 134.1564+/-0.0008min, making it a useful object with which to investigate the evolutionary processes of cataclysmic variables. SDSS J092444.48+080150.9 has a period of 131.2432+/-0.0014min and is probably magnetic. The white dwarf ingress and egress phases are very deep and short, and there is no clear evidence that this object has an accretion disc. SDSS J115207.00+404947.8 and SDSS J152419.33+220920.1 are nearly identical twins, with periods of 97.5+/-0.4 and 93.6+/-0.5min and mass ratios of 0.14+/-0.03 and 0.17+/-0.03, respectively. Their eclipses have well-defined white dwarf and bright spot ingress and egress features, making them excellent candidates for detailed study. All four of the orbital periods presented here are shorter than the 2-3 hour period gap observed in the known population of cataclysmic variables.
- ID:
- ivo://CDS.VizieR/J/ApJ/830/51
- Title:
- FourStar galaxy evolution survey (ZFOURGE)
- Short Name:
- J/ApJ/830/51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The FourStar galaxy evolution survey (ZFOURGE) is a 45 night legacy program with the FourStar near-infrared camera on Magellan and one of the most sensitive surveys to date. ZFOURGE covers a total of 400arcmin^2^ in cosmic fields CDFS, COSMOS and UDS, overlapping the CANDELS fields.
- 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.
1487. FSVS Cluster Catalogue
- ID:
- ivo://CDS.VizieR/J/MNRAS/369/1334
- Title:
- FSVS Cluster Catalogue
- Short Name:
- J/MNRAS/369/1334
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a large sample of 598 galaxy clusters and rich groups discovered in the data of the Faint Sky Variability Survey (FSVS). The clusters have been identified using a fully automated, semiparametric technique based on a maximum likelihood approach applied to Voronoi tessellation, and enhanced by colour discrimination. The sample covers a wide range of richness, has a density of ~28 clusters/deg^2^, and spans a range of estimated redshifts of 0.05<z<0.9 with mean <z>=0.345. Assuming the presence of a cluster red sequence, the uncertainty of the estimated cluster redshifts is assessed to be {sigma}~0.03. Containing over 100 clusters with z>0.6, the catalogue contributes substantially to the current total of optically selected, intermediate-redshift clusters, and complements the existing, usually X-ray selected, samples. The FSVS fields are accessible for observation throughout the whole year, making them particularly suited for large follow-up programmes. The construction of this FSVS Cluster Catalogue completes a fundamental component of our continuing programmes to investigate the environments of quasars and the chemical evolution of galaxies. We publish here the list of all clusters with their basic parameters, and discuss some illustrative examples in more detail. The full FSVS Cluster Catalogue, together with images and lists of member galaxies etc., will be issued as part of the 'NOAO (National Optical Astronomy Observatories) data products', and accessible at http://www.noao.edu/dpp/ . We describe the format of these data and access to them.
- ID:
- ivo://CDS.VizieR/J/ApJ/854/73
- Title:
- Full-data results of HFF: galaxies z~6-9
- Short Name:
- J/ApJ/854/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present UV luminosity functions of dropout galaxies at z~6-10 with the complete Hubble Frontier Fields data. We obtain a catalog of ~450 dropout-galaxy candidates (350, 66, and 40 at z~6-7, 8, and 9, respectively), with UV absolute magnitudes that reach ~-14mag, ~2 mag deeper than the Hubble Ultra Deep Field detection limits. We carefully evaluate number densities of the dropout galaxies by Monte Carlo simulations, including all lensing effects such as magnification, distortion, and multiplication of images as well as detection completeness and contamination effects in a self-consistent manner. We find that UV luminosity functions at z~6-8 have steep faint-end slopes, {alpha}~-2, and likely steeper slopes, {alpha}<~-2 at z~9-10. We also find that the evolution of UV luminosity densities shows a non-accelerated decline beyond z~8 in the case of M_trunc_=-15, but an accelerated one in the case of M_trunc_=-17. We examine whether our results are consistent with the Thomson scattering optical depth from the Planck satellite and the ionized hydrogen fraction Q_HII_ at z<~7 based on the standard analytic reionization model. We find that reionization scenarios exist that consistently explain all of the observational measurements with the allowed parameters of f_esc_=0.17_-0.03_^+0.07^ and M_trunc_>-14.0 for log{xi}_ion_/[erg^-1^Hz]=25.34, where f_esc_ is the escape fraction, Mtrunc is the faint limit of the UV luminosity function, and {xi}_ion_ is the conversion factor of the UV luminosity to the ionizing photon emission rate. The length of the reionization period is estimated to be {Delta}z=3.9_-1.6_^+2.0^ (for 0.1<Q_HII_<0.99), consistent with the recent estimate from Planck.
- ID:
- ivo://CDS.VizieR/J/ApJS/227/3
- Title:
- Full spectroscopic data release of the SPT-GMOS
- Short Name:
- J/ApJS/227/3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500deg^2^ of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W, of [OII]{lambda}{lambda}3727, 3729 and H-{delta}, and the 4000{AA} break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m*). Finally, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ~20% of the full SPT-SZ sample.
- ID:
- ivo://CDS.VizieR/J/A+A/476/217
- Title:
- Fundamental parameters of five old open clusters
- Short Name:
- J/A+A/476/217
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The outer parts of the Milky Way disk are believed to be one of the main arenas where the accretion of external material in the form of dwarf galaxies and subsequent formation of streams is taking place. The Monoceros stream and the Canis Major and Argo over-densities are notorious examples. Understanding whether what we detect is the signature of accretion or, more conservatively, simply the intrinsic nature of the disk, represents one of the major goals of modern Galactic astronomy. We try to shed more light on the properties of the outer disk by exploring the properties of distant anti-center old open clusters. We want to verify whether distant clusters follow the chemical and dynamical behavior of the solar vicinity disk, or whether their properties can be better explained in terms of an extra-galactic population.
