- ID:
- ivo://CDS.VizieR/J/A+A/631/A113
- Title:
- Abund. of disk & bulge giants: Zr, La, Ce, Eu
- Short Name:
- J/A+A/631/A113
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations of the Galactic bulge suggest that the disk formed through secular evolution rather than gas dissipation and/or mergers, as previously believed. This would imply very similar chemistry in the disk and bulge. Some elements, such as the {alpha}-elements, are well studied in the bulge, but others like the neutron-capture elements are much less well explored. Stellar mass and metallicity are factors that affect the neutron-capture process. Due to this, the enrichment of the ISM and the abundance of neutron-capture elements vary with time, making them suitable probes for Galactic chemical evolution. In this work, we make a differential comparison of neutron-capture element abundances determined in the local disk(s) and the bulge, focusing on minimising possible systematic effects in the analysis, with the aim of finding possible differences/similarities between the populations. Abundances are determined for Zr, La, Ce, and Eu in 45 bulge giants and 291 local disk giants, from high-resolution optical spectra. The abundances are determined by fitting synthetic spectra using the SME-code. The disk sample is separated into thin- and thick-disk components using a combination of abundances and kinematics. We find flat Zr, La, and Ce trends in the bulge, with a ~0.1dex higher La abundance compared with the disk, possibly indicating a higher s-process contribution for La in the bulge. [Eu/Fe] decreases with increasing [Fe/H], with a plateau at around [Fe/H]~-0.4, pointing at similar enrichment to {alpha}-elements in all populations. We find that the r-process dominated the neutron-capture production at early times both in the disks and bulge. Further, [La/Eu] ratios for the bulge are systematically higher than for the thick disk, pointing to either a) a different amount of SN II or b) a different contribution of the s-process in the two populations. Considering [(La+Ce)/Zr], the bulge and the thick disk follow each other closely, suggesting a similar ratio of high-to-low-mass asymptotic giant branch stars.
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- ID:
- ivo://CDS.VizieR/J/A+A/621/A133
- Title:
- ABYSS HUDF WFC3 IR mosaics
- Short Name:
- J/A+A/621/A133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hubble Ultra Deep field (HUDF) is the deepest region ever observed with the Hubble Space Telescope. With the main objective of unveiling the nature of galaxies up to z~7-8, the observing and reduction strategy have focused on the properties of small and unresolved objects, rather than the outskirts of the largest objects, which are usually over-subtracted. We aim to create a new set of WFC3 IR mosaics of the HUDF using novel techniques to preserve the properties of the low surface brightness regions. We created ABYSS a pipeline that optimises the estimate and modelling of low-level systematic effects to obtain a robust background subtraction. We have improved four key points in the reduction: 1) creation of new absolute sky flat fields, 2) extended persistence models, 3) dedicated sky background subtraction and 4) robust co-adding. The new mosaics successfully recover the low surface brightness structure removed on the previous HUDF published reductions. The amount of light recovered with a mean surface brightness dimmer than mu=26mag/arcsec^2^ is equivalent to a m=19 mag source when compared to the XDF and a m=20mag compared to the HUDF12. We present a set of techniques to reduce ultra-deep images (mu>32.5mag/arcsec^2^, 3 sigma in 10x10 arcsec boxes), that successfully allow to detect the low surface brightness structure of extended sources on ultra deep surveys. The developed procedures are applicable to HST, JWST, EUCLID and many other space and ground-based observatories. We made the final ABYSS WFC3 IR HUDF mosaics publicly available at http://www.iac.es/proyecto/abyss/.
- ID:
- ivo://CDS.VizieR/J/A+A/632/A78
- Title:
- A case study of the HI content of HCG 16
- Short Name:
- J/A+A/632/A78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Hickson Compact Group (HCG) 16 is a prototypical compact group of galaxies in an intermediate stage of the evolutionary sequence proposed by Verdes-Montenegro et al. (2001A&A...377..812V), where its galaxies are losing gas to the intra-group medium (IGrM). The group hosts galaxies that are HI-normal, HI-poor, centrally active with both AGN and starbursts, as well as a likely new member and a 160kpc long HI tidal feature. Despite being a well-studied group at all wavelengths, no previous study of HCG 16 has focused on its extraordinary HI component. The characteristics of HCG 16 make it an ideal case study for exploring which processes are likely to dominate the late stages of evolution in compact groups, and ultimately determine their end states. In order to build a coherent picture of the evolution of this group we make use of the multi-wavelength data available, but focus particularly on HI as a tracer of interactions and evolutionary phase. We reprocess archival VLA L-band observations of HCG 16 using the multi-scale CLEAN algorithm to accurately recover diffuse features. Tidal features and galaxies are separated in 3 dimensions using the SlicerAstro package. The HI deficiency of the separated galaxies is assessed against the benchmark of recent scaling relations of isolated galaxies. This work has been performed with particular attention to reproducibility and is accompanied by a complete workflow to reproduce all the final data products, figures, and results. Despite the clear disruption of the HI component of HCG 16 we find that it is not globally HI deficient, even though HCG 16a and b have lost the majority of their HI and almost 50% of the group's HI is in the IGrM. The HI content of HCG 16d shows highly disturbed kinematics, with only a marginal velocity gradient that is almost perpendicular to its optical major axis. The ~160kpc long tail extending towards the South-East appears to be part of an even larger structure which spatially and kinematically connects NGC 848 to the North-West corner of the group. This study indicates that in the recent past (1Gyr) galaxies HCG 16a and b likely underwent major interactions that unbound gas without triggering significant star formation. This gas was then swept away by a high speed, close encounter with NGC 848. The starburst events HCG 16c and d, likely initiated by their mutual interaction, have triggered galactic winds which, in the case of HCG 16d, appears to have disrupted its HI reservoir. The tidal features still connected to all these galaxies indicate that more HI will soon be lost to the IGrM, while that which remains in the discs will likely be consumed by star formation episodes triggered by their on-going interaction. This is expected to result in a collection of gas-poor galaxies embedded in a diffuse HI structure, which will gradually (over several Gyr) be evaporated by the UV background, resembling the final stage of the evolutionary model of compact groups.
- ID:
- ivo://CDS.VizieR/J/AJ/131/621
- Title:
- A catalog of 1022 bright contact binary stars
- Short Name:
- J/AJ/131/621
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work we describe a large new sample of contact binary stars extracted in a uniform manner from sky patrol data taken by the ROTSE-I telescope. Extensive ROTSE-I light-curve data are combined with J-, H-, and K-band near-infrared data taken from the Two Micron All Sky Survey to add color information.
- ID:
- ivo://CDS.VizieR/J/AJ/155/180
- Title:
- A catalog of cool dwarf targets for the TESS
- Short Name:
- J/AJ/155/180
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of cool dwarf targets (V-J>2.7, T_eff_~<4000 K) and their stellar properties for the upcoming Transiting Exoplanet Survey Satellite (TESS), for the purpose of determining which cool dwarfs should be observed using two minute observations. TESS has the opportunity to search tens of thousands of nearby, cool, late K- and M-type dwarfs for transiting exoplanets, an order of magnitude more than current or previous transiting exoplanet surveys, such as Kepler, K2, and ground-based programs. This necessitates a new approach to choosing cool dwarf targets. Cool dwarfs are chosen by collating parallax and proper motion catalogs from the literature and subjecting them to a variety of selection criteria. We calculate stellar parameters and TESS magnitudes using the best possible relations from the literature while maintaining uniformity of methods for the sake of reproducibility. We estimate the expected planet yield from TESS observations using statistical results from the Kepler mission, and use these results to choose the best targets for two minute observations, optimizing for small planets for which masses can conceivably be measured using follow-up Doppler spectroscopy by current and future Doppler spectrometers. The catalog is available in machine readable format and is incorporated into the TESS Input Catalog and TESS Candidate Target List until a more complete and accurate cool dwarf catalog identified by ESA's Gaia mission can be incorporated.
- ID:
- ivo://CDS.VizieR/J/A+A/445/765
- Title:
- A Catalog of Edge-on Disk Galaxies
- Short Name:
- J/A+A/445/765
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spiral galaxies range from bulge-dominated early-type galaxies to late types with little or no bulge. Cosmological models do not predict the formation of disk-dominated, essentially bulgeless galaxies, yet these objects exist. A particularly striking and poorly understood example of bulgeless galaxies are flat or superthin galaxies with large axis ratios. We therefore embarked on a study aimed at a better understanding of these enigmatic objects, starting by compiling a statistically meaningful sample with well-defined properties. The disk axis ratios can be most easily measured when galaxies are seen edge-on. We used data from the Sloan Digital Sky Survey (SDSS) in order to identify edge-on galaxies with disks in a uniform, reproducible, automated fashion. In the five-color photometric database of the SDSS Data Release 1 (DR1, http://www.sdss.org/dr1) (2099 deg^2) we identified 3169 edge-on disk galaxies, which we subdivided into disk galaxies with bulge, intermediate types, and simple disk galaxies without any obvious bulge component. We subdivided these types further into subclasses: Sa(f), Sb(f), Sc(f), Scd(f), Sd(f), Irr(f), where the (f) indicates that these galaxies are seen edge-on. Here we present our selection algorithm and the resulting catalogs of the 3169 edge-on disk galaxies including the photometric, morphological, and structural parameters of our targets. A number of incompleteness effects affect our catalog, but it contains almost a factor of four more bulgeless galaxies with prominent simple disks (flat galaxies) within the area covered here than optical previous catalogs, which were based on the visual selection from photographic plates (Karachentsev et al. 1999, see Cat. VII/219). We find that approximately 15% of the edge-on disk galaxies in our catalog are flat galaxies, demonstrating that these galaxies are fairly common, especially among intermediate- mass star-forming galaxies. Bulgeless disks account for roughly one third of our galaxies when also puffy disks and edge-on irregulars are included. Our catalog provides a uniform database for a multitude of follow-up studies of bulgeless galaxies in order to constrain their intrinsic and environmental properties and their evolutionary status.
- ID:
- ivo://CDS.VizieR/J/AJ/143/36
- Title:
- A catalog of Galactic infrared carbon stars
- Short Name:
- J/AJ/143/36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We collected almost all of the Galactic infrared carbon stars (IRCSs) from literature published up to the present to organize a catalog of 974 Galactic IRCSs in this paper. Some of their photometric properties in the near-, mid-, and far-infrared are discussed.
- ID:
- ivo://CDS.VizieR/J/ApJS/245/10
- Title:
- A catalog of galaxies in direction of Perseus
- Short Name:
- J/ApJS/245/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 5437 morphologically classified sources in the direction of the Perseus galaxy cluster core, among them 496 early-type low-mass galaxy candidates. The catalog is primarily based on V-band imaging data acquired with the William Herschel Telescope, which we used to conduct automated source detection and derive photometry. We additionally reduced archival Subaru multiband imaging data in order to measure aperture colors and perform a morphological classification, benefiting from 0.5" seeing conditions in the r-band data. Based on morphological and color properties, we extracted a sample of early-type low-mass galaxy candidates with absolute V-band magnitudes in the range of -10 to -20mag. In the color-magnitude diagram, the galaxies are located where the red sequence for early-type cluster galaxies is expected, and they lie on the literature relation between absolute magnitude and Sersic index. We classified the early-type dwarf candidates into nucleated and nonnucleated galaxies. For the faint candidates, we found a trend of increasing nucleation fraction toward brighter luminosity or higher surface brightness, similar to what is observed in other nearby galaxy clusters. We morphologically classified the remaining sources as likely background elliptical galaxies, late-type galaxies, edge-on disk galaxies, and likely merging systems and discussed the expected contamination fraction through non-early-type cluster galaxies in the magnitude-size surface brightness parameter space. Our catalog reaches its 50% completeness limit at an absolute V-band luminosity of -12mag and a V-band surface brightness of 26mag/arcsec^2^. This makes it the largest and deepest catalog with coherent coverage compared to previous imaging studies of the Perseus cluster.
- ID:
- ivo://org.gavo.dc/pcc/q/cone
- Title:
- A Catalog of Galaxies in the Direction of the Perseus Cluster
- Short Name:
- pcc cone
- Date:
- 27 Dec 2024 08:31:02
- Publisher:
- The GAVO DC team
- Description:
- This is a catalog of 5437 morphologically classified sources in the direction of the Perseus galaxy cluster core, among them 496 early-type low-mass galaxy candidates. The catalog is primarily based on V-band imaging data acquired with the William Herschel Telescope. Additionally, we used archival Subaru multiband imaging data in order to measure aperture colors and to perform a morphological classification. The catalog reaches its 50 per cent completeness limit at an absolute V-band luminosity of -12 mag and a V-band surface brightness of 26 mag arcsec^-2 . In addition to the published table, this service also contains cutout images of the objects investigated.
- ID:
- ivo://CDS.VizieR/J/AJ/160/271
- Title:
- A catalog of ~30000 galaxies with ALFALFA-SDSS
- Short Name:
- J/AJ/160/271
- Date:
- 08 Dec 2021
- Publisher:
- CDS
- Description:
- We present a HI optical catalog of ~30000 galaxies based on the 100% complete Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) survey combined with data from the Sloan Digital Sky Survey (SDSS). Our goal is to facilitate the public use of the completed ALFALFA catalog by providing carefully determined matches to SDSS counterparts, including matches for ~10000 galaxies that do not have SDSS spectra. These identifications can provide a basis for further crossmatching with other surveys using SDSS photometric IDs as a reference point. We derive absolute magnitudes and stellar masses for each galaxy using optical colors combined with an internal reddening correction designed for small- and intermediate-mass galaxies with active star formation. We also provide measures of stellar masses and star formation rates based on infrared and/or ultraviolet photometry for galaxies that are detected by the Wide-field Infrared Survey Explorer and/or the Galaxy Evolution Explorer. Finally, we compare the galaxy population in the ALFALFA-SDSS sample with the populations in several other publicly available galaxy catalogs and confirm that ALFALFA galaxies typically have lower masses and bluer colors.