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- 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:
- 15 Aug 2024 15:16:58
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/772/82
- Title:
- A catalog of globular cluster systems
- Short Name:
- J/ApJ/772/82
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 422 galaxies with published measurements of their globular cluster (GC) populations. Of these, 248 are E galaxies, 93 are S0 galaxies, and 81 are spirals or irregulars. Among various correlations of the total number of GCs with other global galaxy properties, we find that N_GC_ correlates well though nonlinearly with the dynamical mass of the galaxy bulge M_dyn_=4{sigma}_e_^2^R_e_/G, where {sigma}_e_ is the central velocity dispersion and R_e_ the effective radius of the galaxy light profile. We also present updated versions of the GC specific frequency S_N_ and specific mass S_M_ versus host galaxy luminosity and baryonic mass. These graphs exhibit the previously known U-shape: highest S_N_ or S_M_ values occur for either dwarfs or supergiants, but in the midrange of galaxy size (10^9^-10^10^L_{sun}_) the GC numbers fall along a well-defined baseline value of S_N_=~1 or S_M_=0.1, similar among all galaxy types. Along with other recent discussions, we suggest that this trend may represent the effects of feedback, which systematically inhibited early star formation at either very low or very high galaxy mass, but which had its minimum effect for intermediate masses. Our results strongly reinforce recent proposals that GC formation efficiency appears to be most nearly proportional to the galaxy halo mass M_halo_. The mean "absolute" efficiency ratio for GC formation that we derive from the catalog data is M_GCS_/M_halo_=6x10^-5^. We suggest that the galaxy-to-galaxy scatter around this mean value may arise in part because of differences in the relative timing of GC formation versus field-star formation. Finally, we find that an excellent empirical predictor of total GC population for galaxies of all luminosities is N_GC_~(R_e_{sigma}_e_)^1.3^, a result consistent with fundamental plane scaling relations.
- ID:
- ivo://CDS.VizieR/J/AJ/156/121
- Title:
- A catalog of 518 likely open cluster NGC 6405 members
- Short Name:
- J/AJ/156/121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents a combined method of Gaussian mixture model and random forest to compute membership probabilities of stars by using large, high-dimensional data sets. A significant advantage of this method is that it allows us to easily identify likely cluster members in large data sets starting from small training samples. As a benchmark, we select 40318 stars in the field of the open cluster NGC 6405 from the Gaia Data Release 2 (Gaia-DR2, Cat. I/345) by means of all five astrometric (positions, proper motions, and parallax) and photometric parameters. We use this combined method to determine likely cluster members in an eleven-dimensional parameter space. A total number of 518 high-probability (>=0.6) memberships are obtained, and the mean parallax and proper motion of the cluster are determined to be 2.171+/-0.005 mas (461+/-1 pc) and (<{mu}_{alpha}_cos{delta}>, <{mu}_{delta}_>)=(-1.357+/-0.023, -5.823+/-0.020) mas/yr, respectively. In addition, we quantitatively evaluate the relative importance of the parameters for membership determination and find that colors and magnitudes cannot be ignored in membership determination when using the RF method. Our results show that this combined method exhibits good performance in handling arbitrary high-dimensional and large data sets, such as Gaia-DR2, and it can also be used to investigate other open clusters.
- ID:
- ivo://CDS.VizieR/J/AJ/139/1542
- Title:
- A catalog of MIPSGAL disk and ring sources
- Short Name:
- J/AJ/139/1542
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 416 extended, resolved, disk and ringlike objects as detected in the MIPSGAL 24um survey of the Galactic plane. This catalog is the result of a search in the MIPSGAL image data for generally circularly symmetric, extended "bubbles" without prior knowledge or expectation of their physical nature. Most of the objects have no extended counterpart at 8um or 70um, with less than 20% detections at each wavelength. For the 54 objects with central point sources, the sources are nearly always seen in all Infrared Array Camera bands. About 70 objects (16%) have been previously identified, with another 35 listed as Infrared Astronomical Satellite sources.
- ID:
- ivo://CDS.VizieR/J/ApJ/835/223
- Title:
- A catalog of nearby galaxies with Chandra obs.
- Short Name:
- J/ApJ/835/223
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We searched the public archive of the Chandra X-ray Observatory as of 2016 March and assembled a sample of 719 galaxies within 50Mpc with available Advanced CCD Imaging Spectrometer observations. By cross-correlation with the optical or near-infrared nuclei of these galaxies, 314 of them are identified to have an X-ray active galactic nucleus (AGN). The majority of them are low-luminosity AGNs and are unlikely X-ray binaries based upon their spatial distribution and luminosity functions. The AGN fraction is around 60% for elliptical galaxies and early-type spirals, but drops to roughly 20% for Sc and later types, consistent with previous findings in the optical. However, the X-ray survey is more powerful in finding weak AGNs, especially from regions with active star formation that may mask the optical AGN signature. For example, 31% of the H II nuclei are found to harbor an X-ray AGN. For most objects, a single power-law model subject to interstellar absorption is adequate to fit the spectrum, and the typical photon index is found to be around 1.8. For galaxies with a non-detection, their stacked Chandra image shows an X-ray excess with a luminosity of a few times 10^37^erg/s on average around the nuclear region, possibly composed of faint X-ray binaries. This paper reports on the technique and results of the survey; in-depth analysis and discussion of the results will be reported in forthcoming papers.
- ID:
- ivo://CDS.VizieR/J/ApJS/179/195
- Title:
- A catalog of outer ejecta knots in Cas A
- Short Name:
- J/ApJS/179/195
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Hubble Space Telescope images of the core-collapse supernova remnant Cassiopeia A are used to identify high-velocity knots of ejecta located outside the remnant's main emission shell of expanding debris. These ejecta fragments are found near or ahead of the remnant's forward shock front and mostly lie from 120" to 300" in radial distance from the remnant's center of expansion. Filter flux ratios when correlated with published spectra show that these knots can be divided into three emission classes: (1) knots dominated by [NII] {lambda}6548,{lambda}6583 emissions, (2) knots dominated by [OII] {lambda}7319, {lambda}7330 emissions, and (3) knots displaying filter flux ratios suggestive of [SII], [OII], and [ArIII] {lambda}7135 emission line strengths similar to the "fast-moving knots" (FMKs) found in the remnant's bright main shell. Of 1825 knots identified, 444 are strong [NII] emission knots, 192 are strong [OII] emission knots, and 1189 are FMK-like knots. In terms of location around the remnant, 972, 207, and 646 knots are found in the remnant's northeast jet, southwest jet, and non-jet regions, respectively. Assuming a distance of 3.4kpc, derived knot transverse velocities based on proper motion measurements spanning a 9 month interval indicate maximum transverse expansion velocities for these three knot classes of 14500, 13500, and 11500km/s, respectively. We present a catalog of these outlying ejecta clumps comprising finding charts, epoch 2004.2 knot positions, proper motions, photometric filter fluxes, and estimated knot emission type, along with cross-references to previous knot identifications and data. This compilation represents a nearly tenfold increase in the number of outlying, high-velocity ejecta knots identified around the Cassiopeia A remnant.
- ID:
- ivo://CDS.VizieR/J/AJ/150/17
- Title:
- A catalog of point sources toward NGC 1333
- Short Name:
- J/AJ/150/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- I present a catalog of point-source objects toward NGC 1333, resolving a wide variety of confusion about source names (and occasionally positions) in the literature. I incorporate data from optical to radio wavelengths, but focus most of the effort on being complete and accurate from J (1.25{mu}m) to 24{mu}m. The catalog encompasses 52^{deg}^<R.A.<52.5{deg} and 31{deg}<decl.<31.6{deg}. Cross-identifications include those from more than 25 papers and catalogs from 1994 to 2014, primarily those in wide use as origins of nomenclature. Gaps in our knowledge are identified, with the most important being a lack of spectroscopy for spectral types or even confirmation of youth and/or cluster membership. I fit a slope to the spectral energy distribution (SED) between 2 and 24{mu}m for the members (and candidate members) to obtain an SED classification, and I compare the resulting classes to those for the same sources in the literature, and for an SED fit between 2 and 8{mu}m. While there are certainly differences, for the majority of the sources, there is good agreement.
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