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Start Over Subject proper motions Result Type text/xml+votable
201. 5 Galactic GC proper motions from Gaia DR1
ID:
ivo://CDS.VizieR/J/ApJ/839/89
Title:
5 Galactic GC proper motions from Gaia DR1
Short Name:
J/ApJ/839/89
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a pilot study of Galactic globular cluster (GC) proper motion (PM) determinations using Gaia data. We search for GC stars in the Tycho-Gaia Astrometric Solution (TGAS) catalog from Gaia Data Release 1 (DR1), and identify five members of NGC 104 (47 Tucanae), one member of NGC 5272 (M3), five members of NGC 6121 (M4), seven members of NGC 6397, and two members of NGC 6656 (M22). By taking a weighted average of member stars, fully accounting for the correlations between parameters, we estimate the parallax (and, hence, distance) and PM of the GCs. This provides a homogeneous PM study of multiple GCs based on an astrometric catalog with small and well-controlled systematic errors and yields random PM errors similar to existing measurements. Detailed comparison to the available Hubble Space Telescope (HST) measurements generally shows excellent agreement, validating the astrometric quality of both TGAS and HST. By contrast, comparison to ground-based measurements shows that some of those must have systematic errors exceeding the random errors. Our parallax estimates have uncertainties an order of magnitude larger than previous studies, but nevertheless imply distances consistent with previous estimates. By combining our PM measurements with literature positions, distances, and radial velocities, we measure Galactocentric space motions for the clusters and find that these also agree well with previous analyses. Our analysis provides a framework for determining more accurate distances and PMs of Galactic GCs using future Gaia data releases. This will provide crucial constraints on the near end of the cosmic distance ladder and provide accurate GC orbital histories.
202. Galactic halo CEMP stars abundances & kinematics
ID:
ivo://CDS.VizieR/J/A+A/623/A128
Title:
Galactic halo CEMP stars abundances & kinematics
Short Name:
J/A+A/623/A128
Date:
21 Oct 2021
Publisher:
CDS
Description:
Carbon-enhanced metal-poor (CEMP) stars span a wide range of stellar populations, from bona fide second-generation stars to later-forming stars that provide excellent probes of binary mass transfer and stellar evolution. Here we analyse 11 metal-poor stars (8 of which are new to the literature), and demonstrate that 10 are CEMP stars. Based on high signal-to-noise ratio (S/N) X-Shooter spectra, we derive abundances of 20 elements (C, N, O, Na, Mg, Ca, Sc, Ti, Cr, Mn, Fe, Ni, Sr, Y, Ba, La, Ce, Pr, Nd, and Eu). From the high-S/N spectra, we were able to trace the chemical contribution of the rare earth elements (REE) from various possible production sites, finding a preference for metal-poor low-mass asymptotic giant branch (AGB) stars of 1.5M_{sun}_ in CEMP-s stars, while CEMP-r/s stars may indicate a more massive AGB contribution (2-5M_{sun}_). A contribution from the r-process -- possibly from neutron star--neutron star mergers (NSM) -- is also detectable in the REE stellar abundances, especially in the CEMP-r/s sub-group rich in both slow(s)\ and rapid(r) neutron-capture elements. Combining spectroscopic data with Gaia DR2 astrometric data provides a powerful chemodynamical tool for placing CEMP stars in the various Galactic components, and classifying CEMP stars into the four major elemental-abundance sub-groups, which are dictated by their neutron-capture element content. The derived orbital parameters indicate that all but one star in our sample (and the majority of the selected literature stars) belong to the Galactic halo. These stars exhibit a median orbital eccentricity of 0.7, and are found on both prograde and retrograde orbits. We find that the orbital parameters of CEMP-no and CEMP-s stars are remarkably similar in the 98 stars we study. A special case is the CEMP-no star HE 0020-1741, with very low Sr and Ba content, which possesses the most eccentric orbit among the stars in our sample, passing close to the Galactic centre. Finally, we propose an improved scheme to sub-classify the CEMP stars, making use of the Sr/Ba ratio, which can also be used to separate very metal-poor stars from CEMP stars. We explore the use of [Sr/Ba] versus [Ba/Fe] in 93 stars in the metallicity range -4.2<~[Fe/H]<-2. We show that the Sr/Ba ratio can also be successfully used for distinguishing CEMP-s, CEMP-r/s, and CEMP-no stars. Additionally, the Sr/Ba ratio is found to be a powerful astro-nuclear indicator, since the metal-poor AGB stars exhibit very different Sr/Ba ratios compared to fast-rotating massive stars and NSM, and is also reasonably unbiased by NLTE and 3D corrections.
203. Galactic kinematics from YSOs sample
ID:
ivo://CDS.VizieR/J/PAZh/39/601
Title:
Galactic kinematics from YSOs sample
Short Name:
J/PAZh/39/601
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on published sources, we have created a kinematic database on 220 massive (>10M_{sun}_) young Galactic star systems located within <3 kpcof the Sun. Out of them, approximately 100 objects are spectroscopic binary and multiple star systems whose components are massive OB stars; the remaining objects are massive Hipparcos B stars with parallax errors of no more than 10 percent. Based on the entire sample, we have constructed the Galactic rotation curve, determined the circular rotation velocity of the solar neighborhood around the Galactic center R_0_=8kpc, V_0_=259+/-16km/s, and obtained the following spiral density wave parameters: the amplitudes of the radial and azimuthal velocity perturbations f_R_=-10.8+/-1.2km/s, and f_{theta}_=7.9+/-1.3km/s, respectively; the pitch angle for a two-armed spiral pattern i=-6.0+/-0.4deg, with the wavelength of the spiral density wave near the Sun being {lambda}=2.6+/-0.2kpc; and the radial phase of the Sun in the spiral density wave {chi}_{sun}_=-120+/-4{deg}. We show that such peculiarities of the Gould Belt as the local expansion of the system, the velocity ellipsoid vertex deviation, and the significant additional rotation can be explained in terms of the density wave theory. All these effects decrease noticeably once the influence of the spiral density wave on the velocities of nearby stars has been taken into account. The influence of Gould Belt stars on the Galactic parameter estimates has also been revealed. Eliminating them from the kinematic equations has led to the following new values of the spiral density wave parameters: f_{theta}_=2.9+/-2.1km/s and {chi}_{sun}_=-104+/-6{deg}.
204. Galactic orbits of stars with planets
ID:
ivo://CDS.VizieR/J/A+A/384/879
Title:
Galactic orbits of stars with planets
Short Name:
J/A+A/384/879
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have reconstructed the galactic orbits of the parent stars of exoplanets. For comparison, we have recalculated the galactic orbits of stars from the Edvardsson et al. (1993, Cat. <J/A+A/275/101>) catalog. A comparison between the two samples indicates that stars with planets are not kinematically peculiar. At each perigalactic distance stars with planets have a metallicity systematically larger than the average for the comparison sample. We argue that this result favors scenarios where the presence of planets is the cause of the higher metallicity of stars with planets.
205. Galactic plane IPHAS-POSSI proper motion survey
ID:
ivo://CDS.VizieR/J/MNRAS/397/1685
Title:
Galactic plane IPHAS-POSSI proper motion survey
Short Name:
J/MNRAS/397/1685
Date:
21 Oct 2021
Publisher:
CDS
Description:
The IPHAS-POSS-I proper motion survey combines data from the INT Photometric H{alpha} survey (Drew et al., 2005MNRAS.362..753D) with SuperCOSMOS scans of POSS-I plates (Hambly et al., 2001MNRAS.326.1279H). The sample covers roughly 1400deg^2^ of the IPHAS survey area and contains 103058 objects with significant proper motions below 150mas/yr in the magnitude range 13.5<r'< 19. Once the final IPHAS survey is completed the catalogue will be updated.
206. Galactic rotation curve from selected maser
ID:
ivo://CDS.VizieR/J/PAZh/37/281
Title:
Galactic rotation curve from selected maser
Short Name:
J/PAZh/37/281
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on currently available observations of 28 maser sources in 25 star-forming regions with measured trigonometric parallaxes, proper motions, and radial velocities, we have constructed the rotation curve of the Galaxy. Taking different distances to the Galactic center R_0_, we have estimated the peculiar velocity of the Sun, the angular velocity of Galactic rotation, and its three derivatives.
207. Galactic RR Lyrae data
ID:
ivo://CDS.VizieR/J/MNRAS/396/553
Title:
Galactic RR Lyrae data
Short Name:
J/MNRAS/396/553
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use accurate absolute proper motions and Two-Micron All-Sky Survey Ks -band apparent magnitudes for 364 Galactic RR Lyrae variables to determine the kinematical parameters of the Galactic RR Lyrae population and constrain the zero-point of the Ks-band period-luminosity relation for these stars via statistical parallax.
208. Gal. midplane Spitzer/IRAC candidate YSOs (SPICY)
ID:
ivo://CDS.VizieR/J/ApJS/254/33
Title:
Gal. midplane Spitzer/IRAC candidate YSOs (SPICY)
Short Name:
J/ApJS/254/33
Date:
19 Jan 2022 09:09:49
Publisher:
CDS
Description:
We present ~120000 Spitzer/IRAC candidate young stellar objects (YSOs) based on surveys of the Galactic midplane between l~255{deg} and 110{deg}, including the GLIMPSE I, II, and 3D, Vela-Carina, Cygnus X, and SMOG surveys (613 square degrees), augmented by near-infrared catalogs. We employed a classification scheme that uses the flexibility of a tailored statistical learning method and curated YSO data sets to take full advantage of Spitzer's spatial resolution and sensitivity in the mid-infrared ~3-9{mu}m range. Multiwavelength color/magnitude distributions provide intuition about how the classifier separates YSOs from other red IRAC sources and validate that the sample is consistent with expectations for disk/envelope-bearing pre-main-sequence stars. We also identify areas of IRAC color space associated with objects with strong silicate absorption or polycyclic aromatic hydrocarbon emission. Spatial distributions and variability properties help corroborate the youthful nature of our sample. Most of the candidates are in regions with mid-IR nebulosity, associated with star-forming clouds, but others appear distributed in the field. Using Gaia DR2 distance estimates, we find groups of YSO candidates associated with the Local Arm, the Sagittarius-Carina Arm, and the Scutum-Centaurus Arm. Candidate YSOs visible to the Zwicky Transient Facility tend to exhibit higher variability amplitudes than randomly selected field stars of the same magnitude, with many high-amplitude variables having light-curve morphologies characteristic of YSOs. Given that no current or planned instruments will significantly exceed IRAC's spatial resolution while possessing its wide-area mapping capabilities, Spitzer-based catalogs such as ours will remain the main resources for mid-infrared YSOs in the Galactic midplane for the near future.
210. General Catalogue of 33342 stars (GC)
ID:
ivo://CDS.VizieR/I/113A
Title:
General Catalogue of 33342 stars (GC)
Short Name:
I/113A
Date:
21 Oct 2021
Publisher:
CDS
Description:
The GC is a catalog of standard positions and proper motions for (all) stars brighter than magnitude 7, extending from the north to south celestial poles. Several thousand additional stars promising to yield reasonably accurate proper motions were included in the catalog. The objectives of the work were to provide standard positions and motions of accuracy limited only by the character and abundance of the observational material upon which the data were based and thus to provide a rich supply of data to promote research in many astronomical fields. The machine version of the GC includes both The Henry Draper Catalogue and Durchmusterung identifications for all stars, although the published GC contains only one or the other. The 1985 version corrected many errors present in a previous machine version and included probable errors for the positions and centennial proper motions (not present in the previous version). In this version decimal points have been aligned for all but a very few of the secular variations and third terms. These quantities are given with the same precision as in the printed catalog, and the coded spectral types have been omitted. The following quantities are included in the machine but not the published version: galactic coordinates and DM numbers. The following data are in the published but not the machine version: centennial increments of proper motion in right ascension and declination, probable errors of the right ascension and declination at 1950.0, and remarks. The documentation supplied with the machine catalog gives a byte-by-byte format description, indigenous catalog characteristics, code explanation tables, and changes incorporated to produce this and previous Astronomical Data Center versions.

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