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591. Compact galaxies in the local universe
ID:
ivo://CDS.VizieR/J/ApJ/720/723
Title:
Compact galaxies in the local universe
Short Name:
J/ApJ/720/723
Date:
21 Oct 2021
Publisher:
CDS
Description:
We set out to test the claim that the recently identified population of compact, massive, and quiescent galaxies at z~2.3 must undergo significant size evolution to match the properties of galaxies found in the local universe. Using data from the Sloan Digital Sky Survey (SDSS; Data Release 7), we have conducted a search for local red sequence galaxies with sizes and masses comparable to those found at z~2.3. The SDSS spectroscopic target selection algorithm excludes high surface brightness objects; we show that this makes incompleteness a concern for such massive, compact galaxies, particularly for low redshifts (z<~0.05). We have identified 63 M_*_>10^10.7^M_{sun}_ (~5x10^10^M_{sun}_) red sequence galaxies at 0.066<z_spec_<0.12 which are smaller than the median size-mass relation by a factor of 2 or more. Consistent with expectations from the virial theorem, the median offset from the mass-velocity dispersion relation for these galaxies is 0.12 dex. We do not, however, find any galaxies with sizes and masses comparable to those observed at z~2.3, implying a decrease in the comoving number density of these galaxies, at fixed size and mass, by a factor of >~5000. This result cannot be explained by incompleteness: in the 0.066<z<0.12 interval, we estimate that the SDSS spectroscopic sample should typically be >~75% complete for galaxies with the sizes and masses seen at high redshift, although for the very smallest galaxies it may be as low as ~20%. In order to confirm that the absence of such compact massive galaxies in SDSS is not produced by spectroscopic selection effects, we have also looked for such galaxies in the basic SDSS photometric catalog, using photometric redshifts. While we do find signs of a slight bias against massive, compact galaxies, this analysis suggests that the SDSS spectroscopic sample is missing at most a few objects in the regime we consider.
592. Compact Groups in SDSSDR12
ID:
ivo://CDS.VizieR/J/A+A/618/A157
Title:
Compact Groups in SDSSDR12
Short Name:
J/A+A/618/A157
Date:
21 Oct 2021
Publisher:
CDS
Description:
A catalogue of compact groups identified on the SDSS DR12 is provided. Compact Groups were identified in redshift space with a modified Hickson-like algorithm. The catalogue comprises 462 compact groups of which 406 clearly fulfil all the compact group requirements: compactness, isolation and velocity concordance of all of their members. The remaining 56 groups need further redshift information of potentially contaminating sources.
593. Compact groups of galaxies from SDSS-DR12 (MLCG)
ID:
ivo://CDS.VizieR/J/ApJS/225/23
Title:
Compact groups of galaxies from SDSS-DR12 (MLCG)
Short Name:
J/ApJS/225/23
Date:
21 Oct 2021
Publisher:
CDS
Description:
We apply a friends-of-friends algorithm to an enhanced SDSS DR12 spectroscopic catalog, including redshift from the literature to construct a catalog of 1588 N>=3 compact groups of galaxies containing 5178 member galaxies and covering the redshift range 0.01<z<0.19. This catalog contains 18 times as many systems and reaches 3 times the depth of the similar catalog of Barton et al. (1996AJ....112..871B). We construct catalogs from both magnitude-limited and volume-limited galaxy samples. Like Barton et al. we omit the frequently applied isolation criterion in the compact group selection algorithm. Thus the groups selected by fixed projected spatial and rest-frame line-of-sight velocity separation produce a catalog of groups with a redshift-independent median size. In contrast to previous catalogs, the enhanced SDSS DR12 catalog (including galaxies with r<14.5) includes many systems with z<~0.05. The volume-limited samples are unique to this study. The compact group candidates in these samples have a median stellar mass independent of redshift. Groups with velocity dispersion <~100km/s show abundant evidence for ongoing dynamical interactions among the members. The number density of the volume-limited catalogs agrees with previous catalogs at the lowest redshifts but decreases as the redshift increases. The SDSS fiber placement constraints limit the catalog's completeness. In spite of this issue, the volume-limited catalogs provide a promising basis for detailed spatially resolved probes of the impact of galaxy-galaxy interactions within similar dense systems over a broad redshift range.
594. Compact groups of galaxies in SDSS & LAMOST. I.
ID:
ivo://CDS.VizieR/J/ApJS/246/12
Title:
Compact groups of galaxies in SDSS & LAMOST. I.
Short Name:
J/ApJS/246/12
Date:
21 Oct 2021
Publisher:
CDS
Description:
A compact group (CG) is a kind of special galaxy system where the galaxy members are separated at distances of the order of galaxy size. The strong interaction between the galaxy members makes CGs ideal labs for studying the environmental effects on galaxy evolution. The traditional photometric selection algorithm biases against the CG candidates at low redshifts, while the spectroscopic identification technique is affected by the spectroscopic incompleteness of sample galaxies and typically biases against the high redshift candidates. In this study, we combine these two methods and select CGs in the main galaxy sample of the Sloan Digital Sky Survey, where we also have taken the advantages of the complementary redshift measurements from the LAMOST spectral and GAMA surveys. We have obtained the largest and most complete CG samples to date. Our samples include 6144 CGs and 8022 CG candidates, which are unique in the studies of the nature of the CGs and the evolution of the galaxies inside.
595. Compact high-velocity cloud photometry catalog
ID:
ivo://CDS.VizieR/J/ApJ/623/181
Title:
Compact high-velocity cloud photometry catalog
Short Name:
J/ApJ/623/181
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results of a photometric search for giant stars associated with the cores of four high-velocity clouds (HVCs) - two of which are compact HVCs - using the Las Campanas du Pont 2.5m and Cerro Tololo Blanco 4m telescopes in combination with a system of filters (Washington M, T_2_ + DDO51) useful for identifying low surface gravity, evolved stars.
596. Companions to close spectroscopic binaries
ID:
ivo://CDS.VizieR/J/A+A/450/681
Title:
Companions to close spectroscopic binaries
Short Name:
J/A+A/450/681
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have surveyed a sample of 165 solar-type spectroscopic binaries (SB) with periods from 1 to 30 days for higher-order multiplicity. 62 targets have been observed with the NACO adaptive optics system and 13 new physical tertiary companions were detected. Another 12 new wide companions (5 still tentative) were retrieved from the 2MASS (<II/246>) sky survey. Our binaries belong to 161 stellar systems; of these 64 are triple, 11 quadruple and 7 quintuple. After correction for incomplete detection, the fraction of SBs with additional companions is 63+/-5%. We find that this fraction is a strong function of the SB period P, reaching 96% for P<3d and dropping to 36% for P>12d. Period distributions of SBs with and without tertiaries are significantly different, but their mass ratio distributions are identical. New statistical data on the multiplicity of close SBs indicate that their periods and mass ratios were established very early, but periods of SBs within triples were further shortened by angular momentum exchange with companions.
597. Compilation of 289 eclipsing binaries parameters
ID:
ivo://CDS.VizieR/J/AJ/160/131
Title:
Compilation of 289 eclipsing binaries parameters
Short Name:
J/AJ/160/131
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate directly imaging exoplanets around eclipsing binaries using the eclipse as a natural tool for dimming the binary and thus increasing the planet to star brightness contrast. At eclipse, the binary becomes pointlike, making coronagraphy possible. We select binaries where the planet-star contrast would be boosted by >10x during eclipse, making it possible to detect a planet that is >~10x fainter or in a star system that is ~2-3x more massive than otherwise. Our approach will yield insights into planet occurrence rates around binaries versus individual stars. We consider both self-luminous (SL) and reflected light (RL) planets. In the SL case, we select binaries whose age is young enough so that an orbiting SL planet would remain luminous; in U Cep and AC Sct, respectively, our method is sensitive to SL planets of ~4.5 and ~9 M_J_ with current ground- or near-future space-based instruments and ~1.5 and ~6 M_J_ with future ground-based observatories. In the RL case, there are three nearby (<~50 pc) systems-V1412 Aql, RR Cae, and RT Pic-around which a Jupiter-like planet at a planet-star separation of >~20mas might be imaged with future ground- and space-based coronagraphs. A Venus-like planet at the same distance might be detectable around RR Cae and RT Pic. A habitable Earth-like planet represents a challenge; while the planet-star contrast at eclipse and planet flux are accessible with a 6-8m space telescope, the planet-star separation is 1/3-1/4 of the angular separation limit of modern coronagraphy.
598. Compilation of known QSOs for the Gaia mission
ID:
ivo://CDS.VizieR/J/other/RAA/19.29
Title:
Compilation of known QSOs for the Gaia mission
Short Name:
J/other/RAA/19.2
Date:
21 Oct 2021
Publisher:
CDS
Description:
Quasars are essential for astrometric in the sense that they are spatial stationary because of their large distance from the Sun. The European Space Agency (ESA) space astrometric satellite Gaia is scanning the whole sky with unprecedented accuracy up to a few uas level. However, Gaia's two fields of view observations strategy may introduce a parallax bias in the Gaia catalog. Since it presents no significant parallax, quasar is perfect nature object to detect such bias. More importantly, quasars can be used to construct a Celestial Reference Frame in the optical wavelengths in Gaia mission. In this paper, we compile the most reliable quasars existing in literatures.The final compilation (designated as Known Quasars Catalog for Gaia mission, KQCG) contains 1842076 objects, among of them, 797632 objects are found in Gaia DR1 after cross-identifications. This catalog will be very useful in Gaia mission.
599. Compiled catalog of Per OB2 star forming complex
ID:
ivo://CDS.VizieR/J/A+A/384/145
Title:
Compiled catalog of Per OB2 star forming complex
Short Name:
J/A+A/384/145
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Compiled Catalogue (CC) is a photometric and astrometric survey with the center at (RA, DE)_J2000 = (3.86h, 34.6{deg}) and radius of 10 degrees of a nearby region of star formation including the Per OB2 association. The CC is based on recently published astronomical catalogues, e.g. Hipparcos and Tycho-2, and supplemented by relevant astrophysical data from numerous data sources. The CC is complete down to V=11.6mag, in general, and to V=18.5mag in the one square degree field with the IC 348 cluster. The coordinates and proper motions are reduced to the Hipparcos system and the photometry in the Johnson system. Typical accuracies of 1-20mas for coordinates, 1-3mas/yr for proper motions, 0.01-0.05mag for BV magnitudes were achieved for majority of 29452 CC stars (V<12mag). For a large number of stars we also collected parallaxes and spectral classes (about 7000 stars), the R (about 2000 stars), I, J, H, K (about 500 stars) magnitudes, radial velocities (330 stars). Stars in the Compiled Catalogue are sorted in right ascension order.
600. Completed KMOS^3D^ survey NIR obs.
ID:
ivo://CDS.VizieR/J/ApJ/886/124
Title:
Completed KMOS^3D^ survey NIR obs.
Short Name:
J/ApJ/886/124
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the completed KMOS^3D^ survey, an integral field spectroscopic survey of 739 log(M_*_/M_{sun}_)>9 galaxies at 0.6<z<2.7 using the K-band Multi Object Spectrograph (KMOS) at the Very Large Telescope. The KMOS3D survey provides a population-wide census of kinematics, star formation, outflows, and nebular gas conditions both on and off the star-forming galaxy main sequence through the spatially resolved and integrated properties of H{alpha}, [NII], and [SII] emission lines. We detect H{alpha} emission for 91% of galaxies on the main sequence of star formation and 79% overall. The depth of the survey has allowed us to detect galaxies with star formation rates below 1M_{sun}_/yr, as well as to resolve 81% of detected galaxies with >=3 resolution elements along the kinematic major axis. The detection fraction of H{alpha} is a strong function of both color and offset from the main sequence, with the detected and nondetected samples exhibiting different spectral energy distribution shapes. Comparison of H{alpha} and UV+IR star formation rates reveal that dust attenuation corrections may be underestimated by 0.5dex at the highest masses (log(M_*_/M_{sun}_)>10.5). We confirm our first year results of a high rotation-dominated fraction (monotonic velocity gradient and v_rot_/{sigma}_0_>3.36^0.5^) of 77% for the full KMOS^3D^ sample. The rotation-dominated fraction is a function of both stellar mass and redshift, with the strongest evolution measured over the redshift range of the survey for galaxies with log(M_*_/M_{sun}_)<10.5.