- ID:
- ivo://CDS.VizieR/J/PASP/105/36
- Title:
- All-sky uvby photometry of speckle binaries
- Short Name:
- J/PASP/105/36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- All-sky Stroemgren photometric observations were obtained for 303 speckle binaries. Most stars were in the range of V = 5 to 8.These data, when combined with ratios of intensities from the CHARA speckle photometry program, will allow the determination of photometric indices for the individual components of binary stars with separations as small as 0.05 arcsec. These photometric indices will complement the stellar masses from the speckle interferometry observations to provide a much improved mass-luminosity relationship.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/903/145
- Title:
- ALMaQUEST. IV. ALMA-MaNGA QUEnching & star formation
- Short Name:
- J/ApJ/903/145
- Date:
- 15 Mar 2022
- Publisher:
- CDS
- Description:
- The ALMaQUEST (ALMA-MaNGA QUEnching and STar formation) survey is a program with spatially resolved 12CO(1-0) measurements obtained with the Atacama Large Millimeter Array (ALMA) for 46 galaxies selected from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) DR15 optical integral-field spectroscopic survey. The aim of the ALMaQUEST survey is to investigate the dependence of star formation activity on the cold molecular gas content at kiloparsec scales in nearby galaxies. The sample consists of galaxies spanning a wide range in specific star formation rate (sSFR), including starburst (SB), main-sequence (MS), and green valley (GV) galaxies. In this paper, we present the sample selection and characteristics of the ALMA observations and showcase some of the key results enabled by the combination of spatially matched stellar populations and gas measurements. Considering the global (aperture-matched) stellar mass, molecular gas mass, and star formation rate of the sample, we find that the sSFR depends on both the star formation efficiency (SFE) and the molecular gas fraction (f_H_2__), although the correlation with the latter is slightly weaker. Furthermore, the dependence of sSFR on the molecular gas content (SFE or f_H_2__) is stronger than that on either the atomic gas fraction or the molecular-to-atomic gas fraction, albeit with the small Hi sample size. On kiloparsec scales, the variations in both SFE and f_H_2__ within individual galaxies can be as large as 1-2dex, thereby demonstrating that the availability of spatially resolved observations is essential to understand the details of both star formation and quenching processes.
- ID:
- ivo://CDS.VizieR/J/A+A/608/A15
- Title:
- ALMA survey of submm galaxies in COSMOS field
- Short Name:
- J/A+A/608/A15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out targeted ALMA observations of 129 fields in the COSMOS region at 1.25mm, detecting 152 galaxies at S/N>=5 with an average continuum RMS of 150 {mu}Jy. These fields represent a S/N-limited sample of AzTEC/ASTE sources with 1.1mm S/N>=4 over an area of 0.72 square degrees. Given ALMA's fine resolution and the exceptional spectroscopic and multiwavelength photometric data available in COSMOS, this survey allows us unprecedented power in identifying submillimeter galaxy counterparts and determining their redshifts through spectroscopic or photometric means. In addition to 30 sources with prior spectroscopic redshifts, we identified redshifts for 113 galaxies through photometric methods and an additional nine sources with lower limits, which allowed a statistically robust determination of the redshift distribution. We have resolved 33 AzTEC sources into multi-component systems and our redshifts suggest that nine are likely to be physically associated. Our overall redshift distribution peaks at z~2.0 with a high-redshift tail skewing the median redshift to z^~^=2.48+/-0.05. We find that brighter millimeter sources are preferentially found at higher redshifts. Our faintest sources, with S_1.25mm_<1.25mJy, have a median redshift of z^~^=2.18+/-0.09, while the brightest sources, S_1.25mm_>1.8mJy, have a median redshift of z^~^=3.08+/-0.17. After accounting for spectral energy distribution shape and selection effects, these results are consistent with several previous submillimeter galaxy surveys, and moreover, support the conclusion that the submillimeter galaxy redshift distribution is sensitive to survey depth.
- ID:
- ivo://CDS.VizieR/J/ApJ/883/128
- Title:
- alpha & Fe abundances in the giant stellar stream
- Short Name:
- J/ApJ/883/128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first measurements of [Fe/H] and [{alpha}/Fe] abundances, obtained using spectral synthesis modeling, for red giant branch stars in M31's giant stellar stream (GSS). The spectroscopic observations, obtained at a projected distance of 17kpc from M31's center, yielded 61 stars with [Fe/H] measurements, including 21 stars with [{alpha}/Fe] measurements, from 112 targets identified as M31 stars. The [Fe/H] measurements confirm the expectation from photometric metallicity estimates that stars in this region of M31's halo are relatively metal rich compared to stars in the Milky Way's inner halo: more than half the stars in the field, including those not associated with kinematically identified substructure, have [Fe/H] abundances >-1.0. The stars in this field are {alpha}-enhanced at lower metallicities, while [{alpha}/Fe] decreases with increasing [Fe/H] above metallicities of [Fe/H]>~-0.9. Three kinematical components have been previously identified in this field: the GSS, a second kinematically cold feature of unknown origin, and M31's kinematically hot halo. We compare probabilistic [Fe/H] and [{alpha}/Fe] distribution functions for each of the components. The GSS and the second kinematically cold feature have very similar abundance distributions, while the halo component is more metal poor. Although the current sample sizes are small, a comparison of the abundances of stars in the GSS field with abundances of M31 halo and dSph stars from the literature indicate that the progenitor of the stream was likely more massive, and experienced a higher efficiency of star formation, than M31's existing dSphs or the dEs NGC147 and NGC185.
- ID:
- ivo://CDS.VizieR/J/A+A/395/813
- Title:
- Alpha Per faint stars photometry
- Short Name:
- J/A+A/395/813
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a deep, wide-field optical survey of the young stellar cluster Alpha Per, in which we have discovered a large population of candidate brown dwarfs. Subsequent infrared photometric follow-up shows that the majority of them are probable or possible members of the cluster, reaching to a minimum mass of 0.035M_{sun}_.
116. AMIGA III. IRAS data
- ID:
- ivo://CDS.VizieR/J/A+A/462/507
- Title:
- AMIGA III. IRAS data
- Short Name:
- J/A+A/462/507
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the mid- (MIR) and far- (FIR) infrared properties of a large (~1000) sample of the most isolated galaxies in the local Universe. This sample is intended as a "nurture-free" zero point against which more environmentally influenced samples can be compared. We reprocess IRAS MIR/FIR survey data using the ADDSCAN/SCANPI utility for 1030 out of 1050 galaxies from the Catalogue of Isolated Galaxies (CIG, Cat. <VII/82>) as part of the AMIGA survey. We focus on diagnostics (FIR luminosity LFIR , R=log(LFIR/LB) and IRAS colours) thought to be sensitive to effects of environment or interaction.
- ID:
- ivo://CDS.VizieR/J/A+A/449/937
- Title:
- AMIGA. II. Morphological refinement
- Short Name:
- J/A+A/449/937
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a refinement of the optical morphologies for galaxies in the Catalog of Isolated Galaxies (Karachentseva et al., 1973, Cat. <VII/82>) that forms the basis of the AMIGA (Analysis of the interstellar Medium of Isolated GAlaxies) project. Uniform reclassification using the digitized POSS II data benefited from the high resolution and dynamic range of that sky survey. Comparison with independent classifications made for an SDSS overlap sample of more than 200 galaxies confirms the reliability of the early vs. late-type discrimination and the accuracy of spiral subtypes within {Delta}T=1-2. CCD images taken at the Observatorio de Sierra Nevada (OSN) were also used to solve ambiguities in early versus late-type classifications. A considerable number of galaxies in the catalog (n=193) are flagged for the presence of nearby companions or signs of distortion likely due to interaction. This most isolated sample of galaxies in the local Universe is dominated by two populations: 1) 82% are spirals (Sa-Sd) with the bulk being luminous systems with small bulges (63% between types Sb-Sc) and 2) a significant population of early-type E-S0 galaxies (14%).
- ID:
- ivo://CDS.VizieR/J/A+A/436/443
- Title:
- AMIGA. I. Velocities of CIG galaxies
- Short Name:
- J/A+A/436/443
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AMIGA project (Analysis of the Interstellar Medium of Isolated Galaxies) is compiling a multiwavelength database of isolated galaxies that includes optical (B and H{alpha}), infrared (FIR and NIR) and radio (continuum plus HI and CO lines) properties. It involves a refinement of the pioneering Catalog of Isolated Galaxies (<VII/82>). This paper is the first in a series and begins with analysis of the global properties of the nearly redshift-complete Catalog of Isolated Galaxies (CIG) with emphasis on the Optical Luminosity Function (OLF) which we compare with other recent estimates of the OLF for a variety of environments. The CIG redshift distribution for n=956 galaxies re-enforces the evidence for a bimodal structure seen earlier in smaller samples. The peaks at redshift near 1500 and 6000km/s correspond respectively to galaxies in the local supercluster and those in more distant large-scale components (particularly Perseus- Pisces). The two peaks in the redshift distribution are superimposed on 50% or more of the sample that is distributed in a much more homogeneous way. The CIG probably represents the most homogeneous local field example that has ever been compiled. Our derivation of the CIG OLF is consistent with other studies of the OLF for lower density environments. This comparison via the Schechter parameter formalization shows that: 1) M* increases with galaxy surface density on the sky and 2) {alpha} shows a weaker tendency to do the same. The CIG represents the largest and most complete foundation for studies of isolated galaxies and is likely as close as we can come to a field sample.
- ID:
- ivo://CDS.VizieR/J/A+A/470/505
- Title:
- AMIGA IV. Neighbours around CIG galaxies
- Short Name:
- J/A+A/470/505
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Studies of the effects of environment on galaxy properties and evolution require well defined control samples. Such isolated galaxy samples have up to now been small or poorly defined. The AMIGA project (Analysis of the interstellar Medium of Isolated GAlaxies) represents an attempt to define a statistically useful sample of the most isolated galaxies in the local (z<0.05) Universe. A suitable large sample for the AMIGA project already exists, the Catalogue of Isolated Galaxies (CIG, Karachentseva 1973; 1050 galaxies, Cat. VII/82), and we use this sample as a starting point to refine and perform a better quantification of its isolation properties. Digitised POSS-I E images were analysed out to a minimum projected radius R<0.5Mpc around 950 CIG galaxies (those within Vr=1500km/s were excluded). We identified all galaxy candidates in each field brighter than B=17.5 with a high degree of confidence using the LMORPHO software. We generated a catalogue of approximately 54000 potential neighbours (redshifts exist for 30% of this sample). 666 galaxies pass and 284 fail the original CIG isolation criterion. The available redshift data confirm that our catalogue involves a largely background population rather than physically associated neighbours. We find that the exclusion of neighbours within a factor of 4 in size around each CIG galaxy, employed in the original isolation criterion, corresponds to {Delta}Vr~18000km/s indicating that it was a conservative limit. Galaxies in the CIG have been found to show different degrees of isolation. We conclude that a quantitative measure of this is mandatory. It will be the subject of future work based on the catalogue of neighbours obtained here.
- ID:
- ivo://CDS.VizieR/J/A+A/472/121
- Title:
- AMIGA V. Isolation parameters
- Short Name:
- J/A+A/472/121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AMIGA project aims to build a well defined and statistically significant reference sample of isolated galaxies in order to estimate the environmental effects on the formation and evolution of galaxies. The goal of this paper is to provide a measure of the environment of the isolated galaxies in the AMIGA sample, quantifying the influence of the candidate neighbours identified in our previous work and their potential effects on the evolution of the primary galaxies. Here we provide a quantification of the isolation degree of the galaxies in this sample.