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2291. 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.
2292. Near-Earth asteroid (1917) Cuyo opt. and IR obs.
ID:
ivo://CDS.VizieR/J/A+A/627/A172
Title:
Near-Earth asteroid (1917) Cuyo opt. and IR obs.
Short Name:
J/A+A/627/A172
Date:
21 Oct 2021
Publisher:
CDS
Description:
The near-Earth asteroid (1917) Cuyo was subject to radar and light curve observations during a close approach in 1989, and observed up until 2008. It was selected as one of our ESO Large Programme targets, aimed at observational detections of the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect through long-term light curve monitoring and physical modelling of near-Earth asteroids. We aim to constrain the physical properties of Cuyo: shape, spin-state, and spectroscopic & thermophysical properties of the surface. We acquired photometric light curves of Cuyo spanning the period between 2010 and 2013, which we combined with published light curves from 1989-2008. Our thermal-infrared observations were obtained in 2011. Rotationally resolved optical spectroscopy data were acquired in 2011 and combined with all available published spectra to investigate any surface material variegation. We developed a convex light-curve-inversion shape of Cuyo that suggests the presence of an equatorial ridge, typical for an evolved system close to shedding mass due to fast rotation. We determine limits of YORP strength through light-curve-based spin-state modelling, including both negative and positive acceleration values, between -0.7x10^-8^rad/day^2^ and 1.7x10^-8^rad/day^2^. Thermo-physical modelling with the ATPM provides constraints on the geometric albedo, pV=0.24+/-0.07, the effective diameter Deff=3.15+/-0.08km, the thermal inertia =44+/-9J/m^2^/s^1/2^/K, and a roughness fraction of 0.52+/-0.26. This enabled a YORP strength prediction of (-6.39+/-0.96)x10^-10^rad/day^2^. We also see evidence of surface compositional variation. The low value of YORP predicted by means of thermophysical analysis, consistent with the results of the light curve study, might be due to the self-limiting properties of rotational YORP, possibly involving movement of sub-surface and surface material. This may also be consistent with the surface compositional variation that we see. The physical model of Cuyo can be used to investigate cohesive forces as a way to explain why some targets survive rotation rates faster than the fission limit.
2293. Near-Earth Object Survey (MANOS) spectroscopy
ID:
ivo://CDS.VizieR/J/AJ/158/196
Title:
Near-Earth Object Survey (MANOS) spectroscopy
Short Name:
J/AJ/158/196
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Mission Accessible Near-Earth Object Survey (MANOS) aims to observe and characterize small (mean absolute magnitude H~25 mag) Near-Earth Objects (NEOs) that are accessible by spacecraft (mean {Delta}~5.7 km/s) and that make close approaches with the Earth (mean Minimum Orbital Intersection Distance MOID ~0.03 au). We present here the first results of the MANOS visible spectroscopic survey. The spectra were obtained from August 2013 to March 2018 at Lowell Observatory's Discovery Channel 4.3 m telescope, and both Gemini North and South facilities. In total, 210 NEOs have been observed and taxonomically classified. Our taxonomic distribution shows significant variations with respect to surveys of larger objects. We suspect these to be due to a dependence of Main Belt source regions on object size. Compared to previous surveys of larger objects, we report a lower fraction of S+Q-complex asteroids of 43.8+/-4.6%. We associate this decrease with a lack of Phocaea family members at very small size. We also report higher fractions of X-complex and A-type asteroids of 23.8+/-3.3% and 3.8+/-1.3% respectively due to an increase of Hungaria family objects at small size. We find a strong correlation between the Q/S ratio and perihelion distance. We suggest this correlation is due to planetary close encounters with Venus playing a major role in turning asteroids from S to Q-type. This hypothesis is supported by a similar correlation between the Q/S ratio and Venus MOID.
2294. 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%.
2295. 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.
2296. 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.
2297. 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.
2298. 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.
2299. New AY Cam Photometric Observations
ID:
ivo://CDS.VizieR/J/AJ/128/1319
Title:
New AY Cam Photometric Observations
Short Name:
J/AJ/128/1319
Date:
21 Oct 2021
Publisher:
CDS
Description:
New differential UBV photoelectric photometry for the eclipsing binary AY Cam is presented. The Wilson-Devinney program is used to simultaneously solve the three light curves together with previously published radial velocities.
2300. 6 new Beta Cep stars
ID:
ivo://CDS.VizieR/J/A+A/361/245
Title:
6 new Beta Cep stars
Short Name:
J/A+A/361/245
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present ground-based follow-up photometry in the Geneva seven-colour photometric system of six new {beta} Cep stars. The variability of these objects was originally found from the HIPPARCOS mission. The new data provided here allowed us to confirm their {beta} Cep-type nature, to detect the pulsational frequencies and to identify the degrees of the pulsation modes. For definitions of the Geneva photometric system, see <GCPD/13>.