- ID:
- ivo://CDS.VizieR/J/A+A/595/A62
- Title:
- CALIFA galaxies O/H and N/O slopes
- Short Name:
- J/A+A/595/A62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The study of the integrated properties of star-forming galaxies is central to understand their formation and evolution. Some of these properties are extensive and therefore their analysis require totally covering and spatially resolved observations. Among these properties, metallicity can be defined in spiral discs by means of integral field spectroscopy (IFS) of individual HII regions. The simultaneous analysis of the abundances of primary elements, as oxygen, and secondary, as nitrogen, also provides clues about the star formation history and the processes that shape the build-up of spiral discs. Our main aim is to analyse simultaneously O/H and N/O abundance ratios in HII regions in different radial positions of the discs in a large sample of spiral galaxies to obtain the slopes and the characteristic abundance ratios that can be related to their integrated properties. We analysed the optical spectra of individual selected HII regions extracted from a sample of 350 spiral galaxies of the CALIFA survey. We calculated total O/H abundances and, for the first time, N/O ratios using the semi-empirical routine HII-CHI-MISTRY, which, according to Perez-Montero (2014MNRAS.441.2663P), is consistent with the direct method and reduces the uncertainty in the O/H derivation using [NII] lines owing to the dispersion in the O/H-N/O relation. Then we performed linear fittings to the abundances as a function of the de-projected galactocentric distances.
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- ID:
- ivo://CDS.VizieR/J/A+A/593/A114
- Title:
- CALIFA space density distribution of galaxies
- Short Name:
- J/A+A/593/A114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We measure the distribution in absolute magnitude-circular velocity space for a well-defined sample of 199 rotating Calar Alto Legacy Integral Field Area Survey (CALIFA) galaxies using their stellar kinematics. Our aim in this analysis is to avoid subjective selection criteria and to take volume and large-scale structure factors into account. Using stellar velocity fields instead of gas emission line kinematics allows including rapidly rotating early type galaxies. Our initial sample contains 277 galaxies with available stellar velocity fields and growth curve r-band photometry. After rejecting 51 velocity fields that could not be modelled due to the low number of bins, foreground contamination or significant interaction we perform Markov Chain Monte Carlo (MCMC) modelling of the velocity fields, obtaining the rotation curve and kinematic parameters and their realistic uncertainties. We perform an extinction correction and calculate the circular velocity v_circ_ accounting for pressure support a given galaxy has. The resulting galaxy distribution on the M_r_-v_circ_ plane is then modelled as a mixture of two distinct populations, allowing robust a nd reproducible rejection of outliers, a significant fraction of which are slow rotators. The selection effects are understood well enough that the incompleteness of thesample can be corrected for and the 199 galaxies can be weighted by volume and large-scale structure factors enabling us to fit a volume-corrected Tully-Fisher relation (TFR). More importantly, we also provide the volume-corrected distribution of galaxies in the M_r_-v_circ_ plane, which can be compared with cosmological simulations. The joint distribution of the luminosity and circular velocity space densities, representative over the range of -20>M_r_>-22mag, can place more stringent constraints on the galaxy formation and evolution scenarios than linear TFR fit parameters or the luminosity function alone.
- ID:
- ivo://CDS.VizieR/J/AJ/155/89
- Title:
- California-Kepler Survey (CKS). IV. Planets
- Short Name:
- J/AJ/155/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Probing the connection between a star's metallicity and the presence and properties of any associated planets offers an observational link between conditions during the epoch of planet formation and mature planetary systems. We explore this connection by analyzing the metallicities of Kepler target stars and the subset of stars found to host transiting planets. After correcting for survey incompleteness, we measure planet occurrence: the number of planets per 100 stars with a given metallicity M. Planet occurrence correlates with metallicity for some, but not all, planet sizes and orbital periods. For warm super-Earths having P=10-100 days and R_P_=1.0-1.7 R_{Earth}_, planet occurrence is nearly constant over metallicities spanning -0.4 to +0.4 dex. We find 20 warm super-Earths per 100 stars, regardless of metallicity. In contrast, the occurrence of warm sub-Neptunes (R_P_=1.7-4.0 R_{Earth}_) doubles over that same metallicity interval, from 20 to 40 planets per 100 stars. We model the distribution of planets as df{prop.to}10^{beta}M^dM, where {beta} characterizes the strength of any metallicity correlation. This correlation steepens with decreasing orbital period and increasing planet size. For warm super-Earths {beta}=-0.3_-0.2_^+0.2^, while for hot Jupiters {beta}=+3.4_-0.8_^+0.9^. High metallicities in protoplanetary disks may increase the mass of the largest rocky cores or the speed at which they are assembled, enhancing the production of planets larger than 1.7 R_{Earth}_. The association between high metallicity and short-period planets may reflect disk density profiles that facilitate the inward migration of solids or higher rates of planet-planet scattering.
- ID:
- ivo://CDS.VizieR/J/AJ/155/48
- Title:
- California-Kepler Survey (CKS). V. Masses and radii
- Short Name:
- J/AJ/155/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have established precise planet radii, semimajor axes, incident stellar fluxes, and stellar masses for 909 planets in 355 multi-planet systems discovered by Kepler. In this sample, we find that planets within a single multi-planet system have correlated sizes: each planet is more likely to be the size of its neighbor than a size drawn at random from the distribution of observed planet sizes. In systems with three or more planets, the planets tend to have a regular spacing: the orbital period ratios of adjacent pairs of planets are correlated. Furthermore, the orbital period ratios are smaller in systems with smaller planets, suggesting that the patterns in planet sizes and spacing are linked through formation and/or subsequent orbital dynamics. Yet, we find that essentially no planets have orbital period ratios smaller than 1.2, regardless of planet size. Using empirical mass-radius relationships, we estimate the mutual Hill separations of planet pairs. We find that 93% of the planet pairs are at least 10 mutual Hill radii apart, and that a spacing of ~20 mutual Hill radii is most common. We also find that when comparing planet sizes, the outer planet is larger in 65%+/-0.4% of cases, and the typical ratio of the outer to inner planet size is positively correlated with the temperature difference between the planets. This could be the result of photo-evaporation.
- ID:
- ivo://CDS.VizieR/J/ApJ/823/95
- Title:
- CANDELS GOODS-S sources Chandra counterparts
- Short Name:
- J/ApJ/823/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Improving the capabilities of detecting faint X-ray sources is fundamental to increase the statistics on faint high-z AGN and star-forming galaxies. We performed a simultaneous Maximum Likelihood PSF fit in the [0.5-2]keV and [2-7]keV energy bands of the 4Ms Chandra Deep Field South (CDFS) data at the position of the 34930 CANDELS H-band selected galaxies. For each detected source we provide X-ray photometry and optical counterpart validation. We validated this technique by means of a raytracing simulation. We detected a total of 698 X-ray point-sources with a likelihood L>4.98 (i.e.> 2.7{sigma}). We show that the prior knowledge of a deep sample of Optical-NIR galaxies leads to a significant increase of the detection of faint (i.e. ~10^-17^cgs in the [0.5-2]keV band) sources with respect to "blind" X-ray detections. By including previous catalogs, this work increases the total number of X-ray sources detected in the 4Ms CDFS, CANDELS area to 793, which represents the largest sample of extremely faint X-ray sources assembled to date. Our results suggest that a large fraction of the optical counterparts of our X-ray sources determined by likelihood ratio actually coincides with the priors used for the source detection. Most of th e new detected sources are likely star-forming galaxies or faint absorbed AGN. We identified a few sources sources with putative photometric redshift z>4. Despite the low number statistics, this sample significantly increases the number of X-ray selected candidate high-z AGN.
- ID:
- ivo://CDS.VizieR/J/ApJS/206/10
- Title:
- CANDELS multiwavelength catalog
- Short Name:
- J/ApJS/206/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the multiwavelength ultraviolet to mid-infrared catalog of the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra-Deep Survey field observed as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). Based on publicly available data, the catalog includes the CANDELS data from the Hubble Space Telescope (near-infrared WFC3 F125W and F160W data and visible ACS F606W and F814W data); u-band data from CFHT/Megacam; B, V, Rc, i', and z' band data from Subaru/Suprime-Cam; Y and Ks band data from VLT/HAWK-I; J, H, and K band data from UKIDSS (Data Release 8); and Spitzer/IRAC data (3.6, 4.5um from SEDS; 5.8 and 8.0um from SpUDS). The present catalog is F160W-selected and contains 35932 sources over an area of 201.7arcmin^2^ and includes radio- and X-ray-detected sources and spectroscopic redshifts available for 210 sources.
- ID:
- ivo://CDS.VizieR/J/ApJ/775/106
- Title:
- CANDELS passive and massive early-type galaxies
- Short Name:
- J/ApJ/775/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the evolution of the number density, as a function of the size, of passive early-type galaxies (ETGs) with a wide range of stellar masses (10^10^M_{sun}_<M_*_<~10^11.5^M_{sun}_) from z~3 to z~1, exploiting the unique data set available in the GOODS-South field, including the recently obtained WFC3 images as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). In particular, we select a sample of ~107 massive (M_*_>10^10^M_{sun}_), passive (SSFR<10^-2^/Gyr), and morphologically spheroidal galaxies at 1.2<z<3, taking advantage of the panchromatic data set available for GOODS, including VLT, CFHT, Spitzer, Chandra, and HST ACS+WFC3 data. We find that at 1<z<3 the passively evolving ETGs are the reddest and most massive objects in the universe, and we prove that a correlation between mass, morphology, color, and star formation activity is already in place at that epoch. We measure a significant evolution in the mass-size relation of passive ETGs from z~3 to z~1, with galaxies growing on average by a factor of two in size in a 3Gyr timescale only. We also witness an increase in the number density of passive ETGs of 50 times over the same time interval. We find that the first ETGs to form at z>~2 are all compact or ultra-compact, while normal-sized ETGs (meaning ETGs with sizes comparable to those of local counterparts of the same mass) are the most common ETGs only at z<1. The increase of the average size of ETGs at 0<z<1 is primarily driven by the appearance of new large ETGs rather than by the size increase of individual galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/509/A81
- Title:
- Candidate clusters detected in six CFHTLS fields
- Short Name:
- J/A+A/509/A81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Counting clusters is one of the methods to constrain cosmological parameters, but has been limited up to now both by the redshift range and by the relatively small sizes of the homogeneously surveyed areas. In order to enlarge publicly available optical cluster catalogs, in particular at high redshift, we have performed a systematic search for clusters of galaxies in the Canada France Hawaii Telescope Legacy Survey (CFHTLS). We considered the deep 2, 3 and 4 CFHTLS Deep fields (each 1x1deg^2^), as well as the wide 1, 3 and 4 CFHTLS Wide fields. We used the Le Phare photometric redshifts for the galaxies detected in these fields with magnitude limits of i'=25 and 23 for the Deep and Wide fields respectively. We then constructed galaxy density maps in photometric redshift bins of 0.1 based on an adaptive kernel technique and detected structures with SExtractor at various detection levels. In order to assess the validity of our cluster detection rates, we applied a similar procedure to galaxies in Millennium simulations. We measured the correlation function of our cluster candidates. We analyzed large scale properties and substructures, including filaments, by applying a minimal spanning tree algorithm both to our data and to the Millennium simulations.
- ID:
- ivo://CDS.VizieR/J/MNRAS/466/163
- Title:
- Candidate Halpha sources in GBS
- Short Name:
- J/MNRAS/466/163
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of candidate Halpha emission and absorption line sources and blue objects in the Galactic Bulge Survey (GBS) region. We use a point source catalogue of the GBS fields (two strips of (lxb)=(6{deg}x1{deg}) centred at b=1.5{deg} above and below the Galactic centre), covering the magnitude range 16>=r'>=22.5. We utilize (r'-i', r'-Halpha) colour-colour diagrams to select Halpha emission and absorption line candidates, and also identify blue objects (compared to field stars) using the r'-i' colour index. We identify 1337 Halpha emission line candidates and 336 Halpha absorption line candidates. These catalogues likely contain a plethora of sources, ranging from active (binary) stars, early-type emission line objects, cataclysmic variables (CVs) and low-mass X-ray binaries (LMXBs) to background active galactic nuclei (AGN). The 389 blue objects we identify are likely systems containing a compact object, such as CVs, planetary nebulae and LMXBs. Hot subluminous dwarfs (sdO/B stars) are also expected to be found as blue outliers. Crossmatching our outliers with the GBS X-ray catalogue yields sixteen sources, including seven (magnetic) CVs and one qLMXB candidate among the emission line candidates, and one background AGN for the absorption line candidates. One of the blue outliers is a high state AM CVn system. Spectroscopic observations combined with the multi-wavelength coverage of this area, including X-ray, ultraviolet and (time-resolved) optical and infrared observations, can be used to further constrain the nature of individual sources.
- ID:
- ivo://CDS.VizieR/J/A+A/504/291
- Title:
- Candidate Planetary Nebulae in IPHAS catalog
- Short Name:
- J/A+A/504/291
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out a semi-automated search for planetary nebulae (PNe) in the INT Photometric H-Alpha Survey (IPHAS) catalogue. We present the PN search and the list of selected candidates. We cross correlate the selected candidates with a number of existing infrared galactic surveys in order to gain further insight into the nature of the candidates. Spectroscopy of a subset of objects is used to estimate the number of PNe present in the entire candidate list. The overall aim of the IPHAS PN project is to carry out a deep census of PNe in the northern Galactic plane, an area where PN detections are clearly lacking. The PN search is carried out on the IPHAS photometric catalogues. The candidate selection is based on the IPHAS and 2MASS/UKIDSS colours of the objects and the final candidate selection is made visually.