- ID:
- ivo://CDS.VizieR/J/ApJ/824/71
- Title:
- Compact star clusters in M51 with HST
- Short Name:
- J/ApJ/824/71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalog of 3816 compact star clusters in the grand design spiral galaxy M51 based on observations taken with the Hubble Space Telescope (HST). The age distribution of the clusters declines starting at very young ages, and can be represented by a power law, dN/d{tau}{propto}{tau}^gamma^, with {gamma}=-0.65+/-0.15. No significant changes in the shape of the age distribution at different masses is observed. The mass function of the clusters younger than {tau}~400Myr can also be described by a power law, dN/dM{propto}M^{beta}^, with {beta}~-2.1+/-0.2. We compare these distributions with the predictions from various cluster disruption models, and find that they are consistent with models where clusters disrupt approximately independent of their initial mass, but not with models where lower mass clusters are disrupted earlier than their higher mass counterparts. We find that the half-light radii of clusters more massive than M~3x10^4^M_{sun}_ and with ages between 100 and 400Myr are larger by a factor of ~3-4 than their counterparts that are younger than 10^7^ years old, suggesting that the clusters physically expand during their early life.
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- ID:
- ivo://CDS.VizieR/J/ApJ/703/1872
- Title:
- Compact star clusters in the M31 disk
- Short Name:
- J/ApJ/703/1872
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out a survey of compact star clusters (apparent size <~3") in the southwest part of the M31 galaxy, based on the high-resolution Suprime-Cam images (17.5'x28.5'), covering ~15% of the deprojected galaxy disk area. The UBVRI photometry of 285 cluster candidates (V<~20.5mag) was performed using frames of the Local Group Galaxies Survey. The final sample, containing 238 high probability star cluster candidates (typical half-light radius r_h_~1.5pc), was selected by specifying a lower limit of r_h_>~0.15" (>~0.6pc). We derived cluster parameters based on the photometric data and multiband images by employing simple stellar population models. The clusters have a wide range of ages from ~5Myr (young objects associated with 24um and/or H{alpha} emission) to ~10Gyr (globular cluster candidates), and possess mass in a range of 3.0<~log(m/m_{sun}_)<~4.3 peaking at m~4000m_{sun}_. Typical age of these intermediate-mass clusters is in the range of 30Myr<~t<~3Gyr, with a prominent peak at ~70Myr. These findings suggest a rich intermediate-mass star cluster population in M31, which appears to be scarce in the Milky Way galaxy.
- 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.
- ID:
- ivo://CDS.VizieR/J/AJ/126/1707
- Title:
- Companions of bright barred galaxies
- Short Name:
- J/AJ/126/1707
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Companion galaxy environment for a subset of 78 bright and nearby barred galaxies from the Shapley-Ames Catalog is presented. Among the spiral barred galaxies, there are Seyfert galaxies, galaxies with circumnuclear structures, galaxies not associated with any large-scale galaxy cloud structure, galaxies with peculiar disk morphology (crooked arms), and galaxies with normal disk morphology; the list includes all Hubble types. The companion galaxy list includes the number of companion galaxies within 20 diameters, their Hubble type, and projected separation distance.
- ID:
- ivo://CDS.VizieR/J/ApJ/511/612
- Title:
- Comparison of Radio-loud and Quiet Quasars
- Short Name:
- J/ApJ/511/612
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have made radio observations of 87 optically selected quasars at 5 GHz with the VLA in order to measure the radio power for these objects and hence determine how the fraction of radio-loud quasars varies with redshift and optical luminosity. The sample has been selected from the recently completed Edinburgh Quasar Survey and covers a redshift range of 0.3{<=}z{<=}1.5 and an optical absolute magnitude range of (-26.5){<=}M_B_{<=}(-23.5) (h=1/2, q_o_=1/2). We have also matched other existing surveys with the Faint Images of the Radio Sky at Twenty Centimeters and NRAO VLA Sky Survey radio catalogs and combined these data so that the optical luminosity-redshift plane is now far better sampled than before. We have fitted a model to the probability of a quasar being radio-loud as a function of absolute magnitude and redshift, and from this model we infer the radio-loud and radio-quiet optical luminosity functions. The radio-loud optical luminosity function is featureless and flatter than the radio-quiet one. It evolves at a marginally slower rate if quasars evolve by density evolution, but the difference in the rate of evolutions of the two different classes is much less than was previously thought.
- ID:
- ivo://CDS.VizieR/J/ApJS/178/280
- Title:
- Compendium of ISO far-IR extragalactic data
- Short Name:
- J/ApJS/178/280
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Far-infrared line and continuum fluxes are presented for a sample of 227 galaxies observed with the Long Wavelength Spectrometer on the Infrared Space Observatory (ISO, Kessler et al., 1996A&A...315L..27K). The galaxy sample includes normal star-forming systems, starbursts, and active galactic nuclei covering a wide range of colors and morphologies. The data set spans some 1300 line fluxes, 600 line upper limits, and 800 continuum fluxes. Several fine-structure emission lines are detected that arise in either photodissociation or HII regions: [OIII] 52um, [NIII] 57um, [OI] 63um, [OIII] 88um, [NII] 122um, [OI] 145um, and [CII] 158um. Molecular lines such as OH at 53, 79, 84, 119, and 163um, and H_2_O at 58, 66, 75, 101, and 108um are also detected in some galaxies. In addition to those lines emitted by the target galaxies, serendipitous detections of Milky Way [CII] 158um and an unidentified line near 74um in NGC 1068 are also reported. Finally, continuum fluxes at 52, 57, 63, 88, 122, 145, 158, and 170um are derived for a subset of galaxies in which the far-infrared emission is contained within the ~75" ISO LWS beam. The statistics of this large database of continuum and line fluxes, including trends in line ratios with the far-infrared color and infrared-to-optical ratio, are explored.
- ID:
- ivo://CDS.VizieR/VIII/56
- Title:
- Compendium of Radio Measurements of Bright Galaxies
- Short Name:
- VIII/56
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains all radio measurements of optically bright 'normal' galaxies available up until publication of this compendium in 1975. The compendium was originally intended to simplify statistical analysis of radio properties of these normal galaxies. No data processing was carried out (except to bring the data into a consistent format) and no identification was attempted. These data were originally published as Haynes R.F., Huchtmeier W.K.H., Siegman B., and Wright A.E., CSIRO Publication, 1975. The electronic version of this catalog has made small changes to the original version in an attempt to better identify positions with their source names. Where there was no entry on a line for the source name or position in the published version, data from the previous line was repeated.
- ID:
- ivo://CDS.VizieR/J/ApJ/897/111
- Title:
- Compilation of black hole, bulge and stellar masses
- Short Name:
- J/ApJ/897/111
- Date:
- 16 Mar 2022 00:27:27
- Publisher:
- CDS
- Description:
- We present a multiwavelength study of the active galactic nucleus in the nearby (D=14.1Mpc) low-mass galaxy IC750, which has circumnuclear 22GHz water maser emission. The masers trace a nearly edge-on, warped disk ~0.2pc in diameter, coincident with the compact nuclear X-ray source that lies at the base of the ~kiloparsec-scale extended X-ray emission. The position-velocity structure of the maser emission indicates that the central black hole (BH) has a mass less than 1.4x105M{sun}. Keplerian rotation curves fitted to these data yield enclosed masses between 4.1x104M{sun} and 1.4x105M{sun}, with a mode of 7.2x104M{sun}. Fitting the optical spectrum, we measure a nuclear stellar velocity dispersion {sigma }*=110.7_-13.4_^+12.1^km/s. From near-infrared photometry, we fit a bulge mass of (7.3{+/-}2.7)x108M{sun} and a stellar mass of 1.4x1010M{sun}. The mass upper limit of the intermediate-mass BH in IC750 falls roughly two orders of magnitude below the MBH-{sigma}* relation and roughly one order of magnitude below the MBH-MBulge and MBH-M* relations-larger than the relations' intrinsic scatters of 0.58{+/-}0.09dex, 0.69dex, and 0.65{+/-}0.09dex, respectively. These offsets could be due to larger scatter at the low-mass end of these relations. Alternatively, BH growth is intrinsically inefficient in galaxies with low bulge and/or stellar masses, which causes the BHs to be undermassive relative to their hosts, as predicted by some galaxy evolution simulations.
- 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.
- ID:
- ivo://CDS.VizieR/J/AJ/131/1288
- Title:
- Composite spectra of early-type galaxies
- Short Name:
- J/AJ/131/1288
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Chemical abundance indicators are studied using composite spectra, which we provide in tabular form. Tables of line strengths measured from these spectra and parameters derived from these line strengths are also provided. All the objects we analyze were selected from the SDSS database. We selected all objects targeted as galaxies and having Petrosian apparent magnitude 14.5<=r_Pet_<=17.75. To extract a sample of early-type galaxies, we then chose the subset with the spectroscopic parameter eclass<0, which classifies the spectral type based on a principal component analysis, and the photometric parameter fracDev_r_>0.8, which is a seeing-corrected indicator of morphology.
