- ID:
- ivo://CDS.VizieR/J/ApJ/582/668
- Title:
- Colours and H{alpha} in galaxy pairs
- Short Name:
- J/ApJ/582/668
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galaxy-galaxy interactions rearrange the baryons in galaxies and trigger substantial star formation; the aggregate effects of these interactions on the evolutionary histories of galaxies in the universe are poorly understood. We combine B- and R-band photometry and optical spectroscopy to estimate the strengths and timescales of bursts of triggered star formation in the centers of 190 galaxies in pairs and compact groups. Based on an analysis of the measured colors and EW(H{alpha}), we characterize the preexisting and triggered populations separately. The best-fitting burst scenarios assume stronger reddening corrections for line emission than for the continuum and continuous star formation lasting for >~100Myr. The most realistic scenarios require an initial mass function that is deficient in the highest mass stars. The color of the preexisting stellar population is the most significant source of uncertainty. Triggered star formation contributes substantially (probably >~50%) to the R-band flux in the central regions of several galaxies; tidal tails do not necessarily accompany this star formation. Many of the galaxies in our sample have bluer centers than outskirts, suggesting that pre- or nonmerger interactions may lead to evolution along the Hubble sequence. These objects would appear blue and compact at higher redshifts; the older, redder outskirts of the disks would be difficult to detect. Our data indicate that galaxies with larger separations on the sky contain weaker, and probably older, bursts of star formation on average. However, confirmation of these trends requires further constraints on the colors of the older stellar populations and on the reddening for individual galaxies.
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- ID:
- ivo://CDS.VizieR/J/A+AS/126/67
- Title:
- Coma and Perseus clusters galaxies
- Short Name:
- J/A+AS/126/67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an isophotal shape analysis of galaxies in the Coma and Perseus clusters. These data, together with those of two previous papers, provide two complete samples of galaxies with reliable Hubble types in rich clusters: 1) all galaxies brighter than m_b_=16.5 falling within one degree (=2.3Mpc) from the center of the Coma cluster (187 galaxies), 2) all galaxies brighter than m_(Zwicky)=15.7 in a region of 5 deg 3' times 5 deg 27' around the center of the Perseus cluster (139 galaxies). These two complete samples cover 5 orders of magnitude in galaxy density and span areas of 91 and 17Mpc^2^, clustercentric radii up to 2.3 and 6.4Mpc, for Perseus and Coma respectively. They will be used in subsequent papers to study the dependence of galaxy types on cluster environment and as reference samples in comparisons with distant clusters.
- ID:
- ivo://CDS.VizieR/J/A+A/463/783
- Title:
- Combined astrometric catalogue EOC-3
- Short Name:
- J/A+A/463/783
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the past, we collected the astrometric observations of latitude/universal time variations made worldwide at 33 observatories. These observations, referred to Hipparcos Catalogue, were then used to determine the Earth Orientation Parameters (EOP) at 5-day intervals, covering the interval 1899.7-1992.0. Later on, new astrometric catalogues (such as ARHIP or TYCHO-2) appeared as combination of Hipparcos/Tycho positions with ground-based catalogues. These catalogues yield more accurate proper motions than the original Hipparcos Catalogue. Many of the objects observed in the programmes of monitoring Earth orientation from the ground are double or multiple systems, having non-negligible periodic motions. We aim at obtaining a star catalogue with improved proper motions and quasi-periodic terms reflecting orbital motions of the stars observed in these programmes. We used about 4.5 million observations of latitude/universal time variations, and combined them with the catalogues ARIHIP, TYCHO-2 etc... in order to obtain Earth Orientation Catalogue (EOC). Spectral analysis of ground-based data is made in order to discover which of the observed objects display periodic motions, and the method of least squares is then used to estimate corresponding amplitudes and phases. The third version of the catalogue, EOC-3, contains 4418 different objects (i.e., stars, components of double stars, photocenters). Our attempt leads to a description of more accurate paths of the observed objects that will be eventually used for another determination of the Earth Orientation Parameters in the twentieth century.
- ID:
- ivo://CDS.VizieR/J/ApJ/675/1459
- Title:
- Compact Binary Coalescence Galaxy Catalog
- Short Name:
- J/ApJ/675/1459
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An up-to-date catalog of nearby galaxies considered to be hosts of binary compact objects is provided, with complete information about sky position, distance, extinction-corrected blue luminosity, and error estimates. With our current understanding of binary evolution, rates of formation and coalescence for binary compact objects scale with massive-star formation, and hence the (extinction-corrected) blue luminosity of host galaxies. Coalescence events in binary compact objects are among the most promising gravitational-wave sources for ground-based gravitational-wave detectors such as LIGO. Our catalog and associated error estimates are important for the interpretation of analyses carried out for LIGO, in constraining the rates of compact binary coalescence, given an astrophysical population model for the sources considered.
- ID:
- ivo://CDS.VizieR/J/A+A/391/35
- Title:
- Compact Groups in the UZC galaxy sample
- Short Name:
- J/A+A/391/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Applying an automatic neighbour search algorithm to the 3D UZC galaxy catalogue (Falco et al., 1999, Cat. <J/PASP/111/438>) we have identified 291 compact groups (CGs) with radial velocity between 1000 and 10000km/s. The sample is analysed to investigate whether Triplets display kinematical and morphological characteristics similar to higher order CGs (Multiplets). It is found that Triplets constitute low velocity dispersion structures, have a gas-rich galaxy population and are typically retrieved in sparse environments. Conversely Multiplets show higher velocity dispersion, include few gas-rich members and are generally embedded structures. Evidence hence emerges indicating that Triplets and Multiplets, though sharing a common scale, correspond to different galaxy systems. Triplets are typically field structures whilst Multiplets are mainly subclumps (either temporarily projected or collapsing) within larger structures. Simulations show that selection effects can only partially account for differences, but significant contamination of Triplets by field galaxy interlopers could eventually induce the observed dependences on multiplicity.
- ID:
- ivo://CDS.VizieR/VII/89B
- Title:
- Compact groups of compact galaxies
- Short Name:
- VII/89B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog is a compilation of ten published lists of compact groups of compact galaxies found on the Palomar Sky Survey red charts. The catalog contains 377 groups of compact galaxies and includes identifications, equatorial coordinates, numbers of constituent galaxies, magnitudes of the brightest member, sizes of the groups as a whole, and coefficients of relative compactness.
- ID:
- ivo://CDS.VizieR/J/MNRAS/426/296
- Title:
- Compact Groups of galaxies from 2MASX
- Short Name:
- J/MNRAS/426/296
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a photometric catalogue of compact groups of galaxies (p2MCGs) automatically extracted from the Two-Micron All Sky Survey (2MASS) extended source catalogue. A total of 262 p2MCGs are identified, following the criteria defined by Hickson, of which 230 survive visual inspection (given occasional galaxy fragmentation and blends in the 2MASS parent catalogue). Only one quarter of these 230 groups were previously known compact groups (CGs). Among the 144 p2MCGs that have all their galaxies with known redshifts, 85 (59%) have four or more accordant galaxies. This v2MCG sample of velocity-filtered p2MCGs constitutes the largest sample of CGs (with N>=4) catalogued to date, with both well-defined selection criteria and velocity filtering, and is the first CG sample selected by stellar mass. It is fairly complete up to K_group_~9 and radial velocity of ~6000km/s.
- ID:
- ivo://CDS.VizieR/J/AN/321/101
- Title:
- Compact groups of galaxies in LCRS
- Short Name:
- J/AN/321/101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have recently extracted a catalog of compact groups of galaxies (CGs) from the Las Campanas Redshift Survey. This catalog of Las Campanas Compact Groups (LCCGs) contains 76 CGs with a median redshift of z_med_~0.08. The physical properties of these CGs are similar to those form Hickson (1982, Cat. <VII/213>) and the Barton et al. (1996AJ....112..871B) catalogs. Here, we present an atlas of our catalog and briefly describe its general properties.
- ID:
- ivo://CDS.VizieR/J/MNRAS/315/839
- Title:
- Compact variable radio sources at 151MHz. I.
- Short Name:
- J/MNRAS/315/839
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Cambridge Low-Frequency Synthesis Telescope has been used to produce a representative sample of low-frequency variable sources. 20 fields, each covering an area of approximately 9{deg}x9{deg}cosecDE, have been observed at 151MHz at between 2 and 10 epochs over the period from 1984 to 1996. At each epoch, maps were made with rms noise levels of typically 10^-15^mJy/beam. From a total of ~6000 sources detected on these maps, 207 are found for which the flux density variations between at least two epochs appear significant at greater than the 3{sigma} level. A numerical model is used to assess the true significance of the variability, given the analysis method adopted. This shows that for about half of the sources which appear to vary by >3{sigma} the variability is genuine. For the other half it is caused by random statistical fluctuations; most of the spurious variables vary by <=3.5{sigma} between a single pair of epochs. A catalogue of the variable sources is presented, which includes an estimate of the probability that a given source is a genuine variable. Fractional flux density variations of between 5 and 100% (typically 15-25%) have been detected on a range of time-scales from 1 to 12 years.
170. ComPRASS catalogue
- ID:
- ivo://CDS.VizieR/J/A+A/626/A7
- Title:
- ComPRASS catalogue
- Short Name:
- J/A+A/626/A7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first all-sky catalogue of galaxy clusters and cluster candidates obtained from joint X-ray-SZ detections using observations from the Planck satellite and the ROSAT all-sky survey (RASS). The catalogue contains 2323 objects and has been validated by careful cross-identification with previously known clusters. This validation shows that 1597 candidates correspond to already known clusters, 212 coincide with other cluster candidates still to be confirmed, and the remaining 514 are completely new detections. With respect to Planck catalogues, the ComPRASS catalogue is simultaneously more pure and more complete. Based on the validation results in the SPT and SDSS footprints, the expected purity of the catalogue is at least 84.5%, meaning that more than 365 clusters are expected to be found among the new or still-to-be-confirmed candidates with future validation efforts or specific follow-ups.
