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1671. Nearby massive early-type galaxies from MATLAS
ID:
ivo://CDS.VizieR/J/MNRAS/498/2138
Title:
Nearby massive early-type galaxies from MATLAS
Short Name:
J/MNRAS/498/2138
Date:
12 Jan 2022 05:42:10
Publisher:
CDS
Description:
The morphology of galaxies gives essential constraints on the models of galaxy evolution. The morphology of the features in the low-surface-brightness (LSB) regions of galaxies has not been fully explored yet because of observational difficulties. Here we present the results of our visual inspections of very deep images of a large volume-limited sample of 177 nearby massive early-type galaxies from the MATLAS survey. The images reach a surface-brightness limit of 28.5-29mag/arcsec^2^ in the g' band. Using a dedicated navigation tool and questionnaire, we looked for structures at the outskirts of the galaxies such as tidal shells, streams, tails, disturbed outer isophotes, or peripheral star-forming discs, and simultaneously noted the presence of contaminating sources, such as Galactic cirrus. We also inspected internal substructures such as bars and dust lanes. We discuss the reliability of this visual classification investigating the variety of answers made by the participants. We present the incidence of these structures and the trends of the incidence with the mass of the host galaxy and the density of its environment. We find an incidence of shells, stream, and tails of approximately 15%, about the same for each category. For galaxies with masses over 10^11^M_{sun}_, the incidence of shells and streams increases about 1.7 times. We also note a strong unexpected anticorrelation of the incidence of Galactic cirrus with the environment density of the target galaxy. Correlations with other properties of the galaxies, and comparisons to model predictions, will be presented in future papers.
1672. 24 nearby open clusters TGAS and HSOY reanalysis
ID:
ivo://CDS.VizieR/J/A+A/615/A12
Title:
24 nearby open clusters TGAS and HSOY reanalysis
Short Name:
J/A+A/615/A12
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have determined stellar membership based on astrometry, primarily from TGAS and HSOY, and multi-band photometry for 24 clusters within 333 pc. The fundamental cluster parameters (distance, age, and reddening) have been derived by fitting Padova isochrones (Bressan et al. 2012) to the cluster photometry using a chi-squared minimization.
1673. Nearby radio galaxies FUV to MIR properties
ID:
ivo://CDS.VizieR/J/A+A/581/A33
Title:
Nearby radio galaxies FUV to MIR properties
Short Name:
J/A+A/581/A33
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate whether the far-UV continuum of nearby radio galaxies is due solely to the parent galaxy that passively evolves, or if it reveals evidence for the presence of other star-forming or non-stellar components. If the UV excess is due to an additional radiation component, we compare this with other properties such as radio power, optical spectral type (e.g. high- and low-excitation galaxies), and the strength of the emission lines. We also discuss the possible correlation between the ultraviolet flux, IR properties, and the central black hole mass. We used a sample of low-luminosity B2 radio galaxies and a small sample of higher luminosity 3C radio galaxies at comparable redshift (z<0.2). Spectral energy distributions (SEDs) were constructed using a number of on-line databases that are freely available now: GALEX, SDSS, 2MASS, and WISE. These were compared with model SEDs of early-type galaxies with passively evolving stellar populations at various ages (typically 0.5-1.3x10^9^ years). We established whether a second component was needed to obtain a satisfactory fit with the observed overall SED. We introduce the parameter XUV, which measures the excess slope of the UV continuum between 4500 and 2000{AA} with respect to the UV radiation produced by the underlying old galaxy component. We find that the UV excess as measured by XUV is usually small or absent in low-luminosity (FR I) sources, but sets in abruptly at the transition radio power, above which we find mostly FRII sources. XUV behaves very similarly to the strength of the optical emission lines (in particular H{alpha}). Below P_1.4GHz_<10^24^W/Hz XUV is close to zero. XUV correlates strongly with the H{alpha} line strength, but only in sources with strong H{alpha} emission. We discuss whether the line emission might be due to photoionization by radiation from the parent galaxy, possibly with additional star formation, or if it requires the presence of a non-stellar active galactic nucleus component. XUV and the slope of the mid-IR are strongly correlated, as measured by the WISE bands in the interval 3.4 to 22{mu}m, in the sense that sources with a strong UV excess also have stronger IR emission. There is an inverse correlation between XUV and central black hole mass: the M_BH_ of objects with strong UV excess is on average two to three times less massive than that of objects without UV excess. Low-luminosity radio galaxies tend to be more massive and contain more massive black holes.
1674. Nearby stars in the NLTT catalogue
ID:
ivo://CDS.VizieR/J/AJ/123/2806
Title:
Nearby stars in the NLTT catalogue
Short Name:
J/AJ/123/2806
Date:
21 Oct 2021
Publisher:
CDS
Description:
We are currently undertaking a program aimed at identifying previously unrecognized late-type dwarfs within 20pc of the Sun. As a first step, we have cross-referenced Luyten's NLTT proper-motion catalog (Cat. <I/98>) against the second incremental release of the Two Micron All Sky Survey (2MASS) Point Source Catalog (Cat. <B/2mass>) and use optical/infrared colors, derived by combining Luyten's m_r_ estimates with 2MASS data, to identify candidate nearby stars. This paper describes the definition of a reference sample of 1245 stars and presents a compilation of literature data for more than one-third of the sample. Only 274 stars have trigonometric parallax measurements, but we have used data for nearby stars with well-determined trigonometric parallaxes to compute color-magnitude relations in the (M_V_, V-K), (M_V_, V-I), and (M_I_, I-J) planes and use those relations to determine photometric parallaxes for NLTT stars with optical photometry. Based on the 2MASS JHKs data alone, we have identified a further 42 ultracool dwarfs (J-Ks>0.99) and use J-Ks colors to estimate photometric parallaxes. Combining these various techniques, we identify 308 stars with formal distances of less than 20 pc, while a further 46 have distance estimates within 1{sigma} of survey limit. Of these 354 stars, 75, including 39 of the ultracool dwarfs, are new to nearby-star catalogs. Two stars with both optical and near-infrared photometry are potential additions to the immediate solar neighborhood, with formal distance estimates of less than 10 pc.
1675. Nearby visual double stars UBVRI photometry
ID:
ivo://CDS.VizieR/J/A+A/422/1023
Title:
Nearby visual double stars UBVRI photometry
Short Name:
J/A+A/422/1023
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present accurate CCD astrometric and photometric data for 31 nearby visual double stars in the standard filters BVRI. The observations were collected with a 1.3-m telescope in 2001-2002. The results consist of relative astrometric positions (epoch, angular separation and position angle) and differential BVRI photometry of the components. Mean errors are: 0.01" for the separation; 0.06{deg} for the position angle; and 0.015mag for the photometric data. Comparing the relative positions at different epochs, we evaluate the physical association of the systems. We additionally derive fractional masses and true separations for the most probable binary systems and, whenever orbits are available, also total and component masses.
1676. Nearest stars until 10pc
ID:
ivo://CDS.VizieR/V/101
Title:
Nearest stars until 10pc
Short Name:
V/101
Date:
21 Oct 2021
Publisher:
CDS
Description:
The given catalogue is a revised version of the catalogue (Zakhozhaj, 1987). The previous numeration is preserved, and the stars, with trigonometric, photometric and spectral parallaxes >0.100" are presented. The catalogue contains data on new components of multiple visual systems, on the components of spectral-binary systems, on invisible components with masses >0.08 solar mass. New data are obtained in 90s and contained in the articles [2-6]. The catalogue contains the main characteristics of stars such as the positions, proper motions, radial velocities, parallaxes, photometrical data and also new data of masses and radii of stars. The completeness of the catalogue is about 70%.
1677. Near-IR spectroscopy follow-up of 60 SDSS-DR7 QSOs
ID:
ivo://CDS.VizieR/J/ApJ/753/125
Title:
Near-IR spectroscopy follow-up of 60 SDSS-DR7 QSOs
Short Name:
J/ApJ/753/125
Date:
21 Oct 2021
Publisher:
CDS
Description:
Single-epoch virial black hole (BH) mass estimators utilizing broad emission lines have been routinely applied to high-redshift quasars to estimate their BH masses. Depending on the redshift, different line estimators (H{alpha}, H{beta}, MgII{lambda}2798, CIV{lambda}1549) are often used with optical/near-infrared spectroscopy. Here, we use a homogeneous sample of 60 intermediate-redshift (z~1.5-2.2) Sloan Digital Sky Survey quasars with optical and near-infrared spectra covering CIV through H{alpha} to investigate the consistency between different single-epoch virial BH mass estimators.
1678. Neighborhoods of 36 loose groups of galaxies
ID:
ivo://CDS.VizieR/J/AJ/109/1458
Title:
Neighborhoods of 36 loose groups of galaxies
Short Name:
J/AJ/109/1458
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have selected 36 loose groups of galaxies from Ramella et al. 1989, with at least five members, and with mean redshift cz>3200km/s. These groups all lie within the first two "slices" of the CfA redshift survey <VII/164> (RA between 8h and 17h, DE between 2655.5 and 38.5 degrees). For each of these groups, we define the "redshift-space neighbourhood" as a region centered on the group coordinates and delimited by a circle of projected radius 1.5xh^-1^ Mpc on the sky, and by a velocity interval of 3000km/s. Table 2 lists the positions, magnitudes, radial velocities (cz) and their errors, for the members of the groups published in RGH89. Coordinates and magnitudes are from Zwicky's CGCG <VII/4>. Unpublished redshifts are marked with an asterisk in the last column. Table 3 lists galaxies within 1.5Mpc (assuming H0=100) and +/-1500 km/s from the centers of the groups in redshift space. Magnitudes and positions are from the Zwicky-Nielsen merged catalog. Some coordinates are better coordinates than Zwicky's, some come from compilations of redshift data that we have used to complement our measurements. Unpublished redshifts are marked with an asterisk in the last column. In this table some galaxies appear twice because a few groups do overlap. We listed the galaxies in common under the labels of both groups.
1679. NEP raster ROSAT X-ray/Optical catalog
ID:
ivo://CDS.VizieR/J/A+A/645/A95
Title:
NEP raster ROSAT X-ray/Optical catalog
Short Name:
J/A+A/645/A95
Date:
21 Oct 2021
Publisher:
CDS
Description:
The North-Ecliptic Pole is an important region for extragalactic surveys. Deep/wide contiguous surveys are being performed by several space observatories. We analyse all ROSAT pointed and survey observations within 40deg^2^ around the NEP, restricting the field-of-view to the inner 30' radius. We obtain an X-ray catalogue of 805 sources with 0.5-2keV fluxes >2.9*10^-15^erg/cm^2^/s, a factor of three deeper than the ROSAT All-Sky Survey in this field. The sensitivity and angular resolution of our data are comparable to the eROSITA All-Sky Survey expectations. The 50% position error radius of the sample of X-ray sources is ~10". We use HEROES optical and near-infrared imaging photometry from Subaru and CFHT telescopes together with literature catalogues and a new deep and wide Spitzer survey in the field to identify X-ray sources and calculate photometric redshifts for the candidate counterparts. In particular we utilize mid-IR colours to identify AGN X-ray counterparts. Despite relatively large error circles and faint counterparts, confusion and systematic errors, we obtain a rather reliable catalogue of 766 optical counterparts, redshifts and optical classifications. We find a new population of luminous absorbed X-ray AGN at large redshifts, not recognized in previous X-ray surveys, but identified in our work due to the unique combination of survey solid angle, X-ray sensitivity and multiwavelength photometry. We also use the WISE and Spitzer photometry to identify a sample of 185 AGN selected purely through mid-IR colours, most of which are not detected by ROSAT. Their redshifts and upper limits to X-ray luminosity and X-ray-to-optical flux ratios are even higher than for the new class of X-ray selected luminous type 2 AGN (AGN2); they are probably a natural extension of this sample. This unique dataset is important as a reference sample for future deep surveys in the NEP region, in particular for eROSITA and also for Euclid and SPHEREX. We predict that most of the absorbed distant AGN should be readily picked up by eROSITA, but they require sensitive mid-IR imaging to be recognized as optical counterparts.
1680. NEP source catalog
ID:
ivo://CDS.VizieR/J/ApJS/172/583
Title:
NEP source catalog
Short Name:
J/ApJS/172/583
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a five-band (u* g' r' i' z') optical photometry catalog of the sources in the North Ecliptic Pole (NEP) region based on deep observations made with MegaCam at CFHT. The source catalog covers about 2 square degree area centered at the NEP and reaches depths of about 26mag for u*, g', r' bands, about 25mag for i' band, and about 24mag for z' band (4{sigma} detection over a 1" aperture). The total number of cataloged sources brighter than r'=23mag is about 56000 including both point sources and extended sources. From the investigation of photometric properties using the color- magnitude diagrams and color-color diagrams, we have found that the colors of extended sources are mostly (u*-r')<3.0 and (g'-z')>0.5. This can be used to separate the extended sources from the point sources reliably, even for the faint source domain where typical morphological classification schemes hardly work efficiently. We have derived an empirical color-redshift relation of the red sequence galaxies using the Sloan Digital Sky Survey data. By applying this relation to our photometry catalog and searching for any spatial overdensities, we have found two galaxy clusters and one nearby galaxy group.