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522. NGC 2000.0
- ID:
- ivo://CDS.VizieR/VII/118
- Title:
- NGC 2000.0
- Short Name:
- VII/118
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- NGC 2000.0 is a modern compilation of the New General Catalogue of Nebulae and Clusters of Stars (NGC), the Index Catalogue (IC), and the Second Index Catalogue compiled by J. L. E. Dreyer (1888, 1895, 1908). The new compilation of these classical catalogs is intended to meet the needs of present-day observers by reporting positions at equinox B2000.0 and by incorporating the corrections reported by Dreyer himself and by a host of other astronomers who have worked with the data and compiled lists of errata. The object types given are those known to modern astronomy. The catalog lists object ID, object type, positions in equinox B2000.0, source of modern data (see NGC 2000 paperback copy), constellation, object size, magnitude, and the description of the object as given by Dreyer. The order of the new catalog is strictly by right ascension, the NGC and IC objects being merged into one machine-readable file.
- ID:
- ivo://CDS.VizieR/J/A+A/622/A8
- Title:
- NGC 3184, 4736, 5055 and 5194 LOFAR & WSRT maps
- Short Name:
- J/A+A/622/A8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Radio continuum (RC) emission in galaxies allows us to measure star formation rates (SFRs) unaffected by extinction due to dust, of which the low-frequency part is uncontaminated from thermal (free-free) emission. We calibrate the conversion from the spatially resolved 140MHz RC emission to the SFR surface density (SFR) at 1kpc scale. Radio spectral indices give us, by means of spectral ageing, a handle on the transport of cosmic rays using the electrons as a proxy for GeV nuclei. We used recent observations of three galaxies (NGC 3184, 4736, and 5055) from the LOFAR Two-metre Sky Survey (LoTSS), and archival LOw Frequency ARay (LOFAR) data of NGC 5194. Maps were created with the facet calibration technique and converted to radio {Sigma}SFR maps using the Condon relation. We compared these maps with hybrid {Sigma}SFR maps from a combination of GALEX far-ultraviolet and Spitzer 24um data using plots tracing the relation at the highest angular resolution allowed by our data at 1.2x1.2-kpc^2^ resolution.
- ID:
- ivo://CDS.VizieR/VIII/89
- Title:
- Northern HI Parkes All Sky Survey Catalogue (HIPASS)
- Short Name:
- VIII/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Northern HIPASS catalogue (NHICAT) is the northern extension of the HIPASS catalogue, HICAT. This extension adds the sky area between the declination (Dec.) range of +2{deg}<DE<+25{deg}30' to HICAT's Dec. range of -90{deg}<DE<+2{deg}. HIPASS is a blind HI survey using the Parkes Radio Telescope covering 71 per cent of the sky (including this northern extension) and a heliocentric velocity range of -1280 to 12700km/s. The entire Virgo Cluster region has been observed in the Northern HIPASS. The galaxy catalogue, NHICAT, contains 1002 sources with v_hel_>300km/s. Sources with -300<v_hel_<300km/s were excluded to avoid contamination by Galactic emission. In total, the entire HIPASS survey has found 5317 galaxies identified purely by their HI content. The full galaxy catalogue is publicly available at http://hipass.aus-vo.org.
- ID:
- ivo://CDS.VizieR/J/MNRAS/434/336
- Title:
- Nuclear activity in isolated galaxies
- Short Name:
- J/MNRAS/434/336
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectroscopic study of the incidence of active galactic nucleus (AGN) nuclear activity in two samples of isolated galaxies. Our results show that the incidence of non-thermal nuclear activity is about 43 and 31 percent for galaxies with emission lines and 40 and 27 percent for the total sample, respectively. For the first time we have a large number of bona fide isolated galaxies (513 objects), with statistically significant number of all morphological types. A large fraction (~70%) of elliptical galaxies or early-type spirals have an AGN and ~70% of them are low-ionization nuclear emission-line regions. We find a larger fraction of AGN in early morphological types, as also found in the general population of galaxies. Only 3% of the AGN show the presence of broad lines (not a single one can be classified as type 1 AGN). This is an important result which is at odds with the unified model even if we consider warped or clumpy tori. Finally, we interpret the large fraction of AGN in isolated galaxies as the result of secular accretion.
- ID:
- ivo://CDS.VizieR/J/MNRAS/441/3570
- Title:
- Nuclear star clusters in 228 spiral galaxies
- Short Name:
- J/MNRAS/441/3570
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of photometric and structural properties of 228 nuclear star clusters (NSCs) in nearby late-type disc galaxies. These new measurements are derived from a homogeneous analysis of all suitable Wide Field Planetary Camera 2 (WFPC2) images in the Hubble Space Telescope (HST) archive. The luminosity and size of each NSC are derived from an iterative point spread function (PSF) fitting technique, which adapts the fitting area to the effective radius (r_eff_) of the NSC and uses a WFPC2-specific PSF model tailored to the position of each NSC on the detector. The luminosities of NSCs are <=10^8^L_V,{sun}_, and their integrated optical colours suggest a wide spread in age. We confirm that most NSCs have sizes similar to globular clusters (GCs), but find that the largest and brightest NSCs occupy the regime between ultra-compact dwarf (UCD) and the nuclei of early-type galaxies in the size-luminosity plane. The overlap in size, mass, and colour between the different incarnations of compact stellar systems provides a support for the notion that at least some UCDs and the most massive Galactic GCs may be remnant nuclei of disrupted disc galaxies. We find tentative evidence for the NSCs' r_eff_ to be smaller when measured in bluer filters and discuss possible implications of this result. We also highlight a few examples of complex nuclear morphologies, including double nuclei, extended stellar structures, and nuclear F606W excess from either recent (circum-)nuclear star formation and/or a weak active galactic nucleus. Such examples may serve as case studies for ongoing NSC evolution via the two main suggested mechanisms, namely cluster merging and in situ star formation.
- ID:
- ivo://CDS.VizieR/J/MNRAS/472/4878
- Title:
- Number counts predictions for surveys
- Short Name:
- J/MNRAS/472/4878
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We estimate the number counts of line emitters at high redshift and their evolution with cosmic time based on a combination of photometry and spectroscopy. We predict the H{alpha}, H{beta}, [OII], and [OIII] line fluxes for more than 35000 galaxies down to stellar masses of ~10^9^M_{sun}_ in the COSMOS and GOODS-S fields, applying standard conversions and exploiting the spectroscopic coverage of the FMOS-COSMOS survey at z~1.55 to calibrate the predictions. We calculate the number counts of H{alpha}, [OII], and [OIII] emitters down to fluxes of 1x10^-17^erg/cm^2^/s in the range 1.4<z<1.8 covered by the FMOS-COSMOS survey. We model the time evolution of the differential and cumulative H{alpha} counts, steeply declining at the brightest fluxes. We expect ~9300-9700 and ~2300-2900-galaxies/deg^2^ for fluxes >=1x10^-16^ and >=2x10^-16^erg/cm^2^/s over the range of 0.9<z<1.8. We show that the observed evolution of the main sequence of galaxies with redshift is enough to reproduce the observed counts variation at 0.2<z<2.5. We characterize the physical properties of the H{alpha} emitters with fluxes >=2x10^-16^erg/cm^2^/s including their stellar masses, UV sizes, [NII]/H{alpha} ratios and H{alpha} equivalent widths. An aperture of R~R_e_~0.5arcsec maximizes the signal-to-noise ratio for a detection, whilst causing a factor of ~2x flux losses, influencing the recoverable number counts, if neglected. Our approach, based on deep and large photometric data sets, reduces the uncertainties on the number counts due to the selection and spectroscopic samplings whilst exploring low fluxes. We publicly release the line flux predictions for the explored photometric samples.
- ID:
- ivo://CDS.VizieR/J/AJ/138/598
- Title:
- NUV sources in Hubble Ultra Deep Field
- Short Name:
- J/AJ/138/598
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog from the first high-resolution U-band image of the Hubble Ultra Deep Field, taken with Hubble's Wide-Field Planetary Camera 2 through the F300W filter, is presented. We detect 96 U-band objects and compare and combine this catalog with a Great Observatories Origins Deep Survey B-selected catalog that provides B, V, i, and z photometry, spectral types, and photometric redshifts. We have also obtained far-ultraviolet (FUV, 1614{AA}) data with Hubble's Advanced Camera for Surveys Solar Blind Channel (ACS/SBC) and with GALEX. We detected 31 sources with ACS/SBC, 28 with GALEX/FUV, and 45 with GALEX/NUV. The methods of observations, image processing, object identification, catalog preparation, and catalog matching are presented.
- ID:
- ivo://CDS.VizieR/VII/139
- Title:
- Observations of Galaxies 1985-1989
- Short Name:
- VII/139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this catalog a complete list of new publications which include CO observations of external galaxies has been edited so that new observations are reported only once, preferably in refereed journals (pub.dat). Therefore the catalog of publications also serves as an inventory of distinct observational projects. This catalog lists all publications that have appeared since the submission of Verter (1985) and before the end of 1989. For each publication, the number and nature of the observations are summarized.
- ID:
- ivo://CDS.VizieR/J/ApJ/788/72
- Title:
- Observed sample of z~0.7 massive galaxies
- Short Name:
- J/ApJ/788/72
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Detailed studies of the stellar populations of intermediate-redshift galaxies can shed light onto the processes responsible for the growth of the massive galaxy population in the last 8 billion years. We here take a step toward this goal by means of deep, multiobject rest-frame optical spectroscopy, performed with the Inamori Magellan Areal Camera and Spectrograph on the Magellan telescope, of a sample of ~70 galaxies in the Extended Chandra Deep Field South survey with redshift 0.65<=z<=0.75, apparent R>22.7 mag_Vega_, and stellar mass >10^10^ M_{sun}_. We measure velocity dispersion and stellar absorption features for individual sources. We interpret them by means of a large Monte Carlo library of star formation histories, following the Bayesian approach adopted for previous low redshift studies, and derive constraints on the stellar mass, mean stellar age, and stellar metallicity of these galaxies. We characterize for the first time the relations between stellar age and stellar mass and between stellar metallicity and stellar mass at z~0.7 for the galaxy population as a whole and for quiescent and star-forming galaxies separately. These relations of increasing age and metallicity with galaxy mass for the galaxy population as a whole have a similar shape as the z~0.1 analog derived for Sloan Digital Sky Survey galaxies but are shifted by -0.28 dex in age and by -0.13 dex in metallicity, at odds with simple passive evolution. Considering z=0.7 quiescent galaxies alone, we find that no additional star formation and chemical enrichment are required for them to evolve into the present-day quiescent population. However, other observations require the quiescent population to grow from z=0.7 to the present day. This growth could be supplied by the quenching of a fraction of z=0.7 M_{sstarf}_>10^11^ M_{sun}_ star-forming galaxies with metallicities already comparable to those of quiescent galaxies, thus leading to the observed increase of the scatter in age without affecting the metallicity distribution. However, rapid quenching of the entire population of massive star-forming galaxies at z=0.7 would be inconsistent with the age- and metallicity-mass relations for the population as a whole and with the metallicity distribution of star-forming galaxies only, which are, on average, 0.12 dex less metal rich than their local counterparts. This indicates chemical enrichment until the present in at least a fraction of the z=0.7 star-forming galaxies in our sample.
