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4181. Nearby globular clusters photometric catalog
ID:
ivo://CDS.VizieR/J/A+AS/144/5
Title:
Nearby globular clusters photometric catalog
Short Name:
J/A+AS/144/5
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first part of the first large and homogeneous CCD color-magnitude diagram (CMD) data base, comprising 52 nearby Galactic globular clusters (GGC) imaged in the V and I bands using only two telescopes (one for each hemisphere). The observed clusters represent 75% of the known Galactic globulars with (m-M)V<=16.15mag, cover most of the globular cluster metallicity range (-2.2<=[Fe/H]<=-0.4), and span Galactocentric distances from ~1.2 to ~18.5kpc. In this paper, the CMDs for the 39 GGCs observed in the southern hemisphere are presented. The remaining 13 northern hemisphere clusters of the catalog are presented in a companion paper. For four clusters (NGC 4833, NGC 5986, NGC 6543, and NGC 6638) we present for the first time a CMD from CCD data. The typical CMD span from the 22^nd^ V magnitude to the tip of the red giant branch. Based on a large number of standard stars, the absolute photometric calibration is reliable to the ~0.02mag level in both filters. This catalog, because of its homogeneity, is expected to represent a useful data base for the measurement of the main absolute and relative parameters characterizing the CMD of GGCs.
4182. Nearby globular clusters photometric catalog
ID:
ivo://CDS.VizieR/J/A+AS/145/451
Title:
Nearby globular clusters photometric catalog
Short Name:
J/A+AS/145/451
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper we present the second and final part of a large and photometrically homogeneous CCD color-magnitude diagram (CMD) data base, comprising 52 nearby Galactic globular clusters (GGC) imaged in the V and I bands. The catalog has been collected using only two telescopes (one for each hemisphere).
4183. 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.
4184. 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.
4185. 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.
4186. Nearby red clump stars JHK observations
ID:
ivo://CDS.VizieR/J/MNRAS/419/1637
Title:
Nearby red clump stars JHK observations
Short Name:
J/MNRAS/419/1637
Date:
21 Oct 2021
Publisher:
CDS
Description:
High-precision ({sigma}_mag_<0.10) new JHK observations of 226 of the brightest and nearest red clump stars in the solar neighbourhood are used to determine distance moduli for the Large Magellanic Cloud (LMC). The resulting K- and H-band values of 18.47+/-0.02 and 18.49+/-0.06 imply that any correction to the K-band Cepheid PL relation due to metallicity differences between Cepheids in the LMC and the solar neighbourhood must be quite small.
4187. Nearby Seyfert galaxies FIR emissions
ID:
ivo://CDS.VizieR/J/MNRAS/458/4512
Title:
Nearby Seyfert galaxies FIR emissions
Short Name:
J/MNRAS/458/4512
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present far-infrared (FIR) 70-500{mu}m imaging observations obtained with Herschel/Photodetector Array Camera (PACS) and Spectral and Photometric Imaging REceiver (SPIRE) of 33 nearby (median distance of 30Mpc) Seyfert galaxies from the Revised Shapley-Ames (RSA) catalogue. We obtain the FIR nuclear (r=1kpc and r=2kpc) and integrated spectral energy distributions (SEDs). We estimate the unresolved nuclear emission at 70{mu}m and we fit the nuclear and integrated FIR SEDs with a grey body model. We find that the integrated FIR emission of the RSA Seyferts in our sample is dominated by emission from the host galaxy, with dust properties similar to those of normal galaxies (non-AGN). We use four criteria to select galaxies whose nuclear 70{mu}m emission has a significant AGN contribution: (1) elevated 70/160{mu}m flux ratios, (2) spatially resolved, high dust temperature gradient, (3) 70{mu}m excess emission with respect to the fit of the FIR SEDs with a grey body, and (4) excess of nuclear SFR obtained from 70{mu}m over SFR from mid-infrared indicators. 16 galaxies (48 per cent of the initial sample) satisfy at least one of these conditions, whereas 10 satisfy half or more. After careful examination of these, we select six bona fide candidates (18 per cent of the initial sample) and estimate that ~40-70 per cent of their nuclear (r=1-2kpc) 70{mu}m emission is contributed by dust heated by the AGN.
4188. 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.
4189. Nearby supernova rates
ID:
ivo://CDS.VizieR/J/MNRAS/412/1419
Title:
Nearby supernova rates
Short Name:
J/MNRAS/412/1419
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is the first paper of a series in which we present new measurements of the observed rates of supernovae (SNe) in the local Universe, determined from the Lick Observatory Supernova Search. We have obtained 2.3 million observations of 14 882 sample galaxies over an interval of 11 years (1998 March to 2008 December). We considered 1036 SNe detected in our sample and used an optimal subsample of 726 SNe (274 Type Ia SNe, 116 Type Ibc SNe and Type II 324 SNe) to determine our SN rates. This is the largest and most homogeneous set of nearby SNe ever assembled for this purpose, and ours is the first local SN rate analysis based on CCD imaging and modern image-subtraction techniques. In this paper, we lay the foundation of the study.
4190. Nearby ultracool dwarfs in galactic plane
ID:
ivo://CDS.VizieR/J/AJ/126/2449
Title:
Nearby ultracool dwarfs in galactic plane
Short Name:
J/AJ/126/2449
Date:
21 Oct 2021
Publisher:
CDS
Description:
Surveys for nearby low-luminosity dwarfs tend to avoid the crowded regions of the Galactic plane. We have devised near-infrared color-magnitude and color-color selection criteria designed to identify late-type M and early-type L dwarfs within 12pc of the Sun. We use those criteria to search for candidates within the regions of the Galactic plane (|b|<10{deg}) covered by the Second Incremental Data Release from the Two Micron All Sky Survey (<II/241>). Detailed inspection of the available photographic images of the resulting 1299 candidates confirms only two as ultracool dwarfs. Both are known proper-motion stars, identified in the recent survey by Lepine et al. (2003, Cat. <J/AJ/125/1598>). Despite the low numbers, the inferred surface density is consistent with comparable surveys at higher latitudes. We discuss the implications for the luminosity function and consider means of improving the efficiency and scope of photometric surveys in the plane.