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- ID:
- ivo://CDS.VizieR/III/47B
- Title:
- Stellar Radial Velocities 0-20 hrs
- Short Name:
- III/47B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Interim Supplement to the General Catalogue of Stellar Radial Velocities (Evans 1979, ISGCRV) contains radial velocities for stars with right ascensions from O through 20 hours. The ISGCRV is intended as a continuation of the General Catalogue of Stellar Radial Velocities (Wilson 1953, GCRV). The ISGCRV resulted from a literature search and data reduction by D. S. Evans covering approximately the years 1951-1977. It contains adopted velocities on the Mount Wilson system. Unfortunately, the individual mea- surements and the literature references could not be included in this version. Both for this reason, and because the ISGCRV covers only O through 20 hours of right ascension (equinox 1900), the ISGCRV should be used with the Bibliography of Stellar Radial Velocities (Abt and Biggs 1972), or the Bibliographical Star Index Retrieval System (Hill et al. 1984).
- ID:
- ivo://CDS.VizieR/J/AJ/135/2264
- Title:
- Stellar radial velocities in NGC 188
- Short Name:
- J/AJ/135/2264
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of our ongoing radial-velocity (RV) survey of the old (7Gyr) open cluster NGC 188. Our WIYN 3.5m data set spans a time baseline of 11 years, a magnitude range of 12<=V<=16.5 (1.18-0.94M_{sun}_), and a 1{deg} diameter region on the sky. With the addition of a Domain Astrophysical Observatory data set we extend our bright limit to V=10.8 and, for some stars, extend our time baseline to 35 years. Our magnitude limits include solar-mass main-sequence stars, subgiants, giants, and blue stragglers (BSs), and our spatial coverage extends radially to 17pc (~13 core radii). For the WIYN data we present a detailed description of our data reduction process and a thorough analysis of our measurement precision of 0.4km/s for narrow-lined stars. We have measured radial velocities for 1046 stars in the direction of NGC 188, and have calculated RV membership probabilities for stars with >=3 measurements, finding 473 to be likely cluster members.
1944. Stellar rotation in M35
- ID:
- ivo://CDS.VizieR/J/ApJ/695/679
- Title:
- Stellar rotation in M35
- Short Name:
- J/ApJ/695/679
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a five month photometric time-series survey for stellar rotation over a 40'x40' field centered on the 150Myr open cluster M35 (=NGC 2168). We report rotation periods for 441 stars within this field and determine their cluster membership and binarity based on a decade-long radial velocity survey, proper-motion measurements, and multiband photometric observations. We find that 310 of the stars with measured rotation periods are late-type members of M35. The distribution of rotation periods for cluster members span more than 2 orders of magnitude from ~0.1 to 15 days, not constrained by the sampling frequency and the timespan of the survey. With an age between the zero-age main sequence and the Hyades, and with ~6 times more rotation periods than measured in the Pleiades, M35 permit detailed studies of early rotational evolution of late-type stars. Nearly 80% of the 310 rotators lie on two distinct sequences in the color-period plane, and define clear relations between stellar rotation period and color (mass). The M35 color-period diagram enables us to determine timescales for the transition between the two rotational states, of ~60Myr and ~140Myr for G and K dwarfs, respectively.
- ID:
- ivo://CDS.VizieR/J/A+AS/124/61
- Title:
- Stellar Rotation in SB0 galaxies
- Short Name:
- J/A+AS/124/61
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present stellar velocity- and velocity dispersion- data for 13 SB0 galaxies and one SBa, based on 61 spectra collected during a long-term project developed at ESO. Our primary goal is to provide a database widest as possible for the study of the stellar velocity and velocity dispersion fields and for future modeling. New data are presented for six galaxies, while for the remaining SB0s particular kinematical aspects were already discussed in previous papers. We found the following results: a) emission lines were detected in our spectra only for 4 out of 14 galaxies considered. When present, they reveal a very peculiar kinematics, including counter-rotation, warps or radial flows. b) A new case of gas counter-rotation has been found: NGC 7079. c) The velocity dispersion along the bar has a smoother trend than in the rest of the galaxy. However there is, in general, a similarity between the velocity dispersion trend (decreasing or flat) measured along the bar and that outside it. d) The existence of a waving pattern in the stellar rotation curves of bars is confirmed for the galaxies of our sample seen inclined between 30 and 50{deg}. In addition to this effect, the percentage of non-circular stellar motions present in the barred galaxies studied may reach the 20%.
- ID:
- ivo://CDS.VizieR/J/MNRAS/390/1437
- Title:
- Stellar streams in Andromeda (M31)
- Short Name:
- J/MNRAS/390/1437
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectroscopic analysis of five stellar streams ("A", "B", "Cr", "Cp" and "D") as well as the extended star cluster, EC4, which lies within Stream "C", all discovered in the halo of M31 from our Canada-France-Hawaii Telescope/MegaCam survey. These spectroscopic results were initially serendipitous, making use of our existing observations from the DEep Imaging Multi-Object Spectrograph mounted on the Keck II telescope, and thereby emphasizing the ubiquity of tidal streams that account for ~70 per cent of the M31 halo stars in the targeted fields. Subsequent spectroscopy was then procured in Stream "C" and Stream "D" to trace the velocity gradient along the streams. Nine metal-rich ([Fe/H]~-0.7) stars at v_hel_=-349.5km/s, {sigma}_v,corr_~5.1+/-2.5km/s are proposed as a serendipitous detection of Stream "Cr", with follow-up kinematic identification at a further point along the stream. Seven metal-poor ([Fe/H]~-1.3) stars confined to a narrow, 15km/s velocity bin centred at v_hel_=-285.6, {sigma}_v,corr_=4.3^+1.7^_-1.4_km/s represent a kinematic detection of Stream "Cp", again with follow-up kinematic identification further along the stream. For the cluster EC4, candidate member stars with average [Fe/H]~-1.4, are found at v_hel_=-282 suggesting it could be related to Stream "Cp". No similarly obvious cold kinematic candidate is found for Stream "D", although candidates are proposed in both of two spectroscopic pointings along the stream (both at ~-400km/s). Spectroscopy near the edge of Stream "B" suggests a likely kinematic detection at v_hel_~-330, {sigma}_v,corr_~6.9km/s, while a candidate kinematic detection of Stream "A" is found (plausibly associated to M33 rather than M31) with v_hel_~-170, {sigma}_v,corr_=12.5km/s. The low dispersion of the streams in kinematics, physical thickness and metallicity makes it hard to reconcile with a scenario whereby these stream structures as an ensemble are related to the giant southern stream. We conclude that the M31 stellar halo is largely made up of multiple kinematically cold streams.
- ID:
- ivo://CDS.VizieR/J/A+A/593/A123
- Title:
- STELLA-SES Radial Velocities of HD 208472
- Short Name:
- J/A+A/593/A123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- HD 208472 is among the most active RS CVn binaries with cool starspots. Decade-long photometry had shown that the spots seem to change their longitudinal appearance with a period of about six years, coherent with brightness variations. Our aim is to spatially resolve the stellar surface of HD 208472 and related the photometric results to the true longitudinal and latitudinal spot appearance. Furthermore, we investigate surface differential rotation pattern of the star. We employ three years of high resolution, high S/N spectroscopic data from the STELLA robotic observatory and determine new and more precise stellar physical parameters. Pre-calculated synthetic spectra are fit to each of these spectra and new spot-corrected orbital elements are given. A sample of 34 absorption lines per spectrum is used to calculate mean line profiles with a S/N of several hundred. A total of 13 temperature Doppler images are reconstructed from these line profiles with the inversion code iMap. Differential rotation is investigated by cross-correlating successive Doppler images in each observing season. Spots on HD 208472 are distributed preferably at high latitudes and less occasionally around mid-to-low latitudes. No polar-cap like structure is seen at any epoch. We observed a flip-flop event between 2009 and 2010, manifested as a flip of the spot activity from phase 0.0 to phase 0.5, while the overall brightness of the star continued to increase and reached an all-time maximum in 2014. Cross-correlation of successive Doppler images suggests a solar-like differential rotation which is ~15 times weaker in strength compared to the Sun.
- ID:
- ivo://CDS.VizieR/J/ApJ/787/24
- Title:
- Structural parameters of true edge-on galaxies
- Short Name:
- J/ApJ/787/24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of true edge-on disk galaxies automatically selected from the Seventh Data Release of the Sloan Digital Sky Survey (SDSS, Cat. II/294). A visual inspection of the g, r, and i images of about 15000 galaxies allowed us to split the initial sample of edge-on galaxy candidates into 4768 (31.8% of the initial sample) genuine edge-on galaxies, 8350 (55.7%) non-edge-on galaxies, and 1865 (12.5%) edge-on galaxies not suitable for simple automatic analysis because these objects either show signs of interaction and warps, or nearby bright stars project on it. We added more candidate galaxies from RFGC, EFIGI, RC3, and Galaxy Zoo catalogs found in the SDSS footprints. Our final sample consists of 5747 genuine edge-on galaxies. We estimate the structural parameters of the stellar disks (the stellar disk thickness, radial scale length, and central surface brightness) in the galaxies by analyzing photometric profiles in each of the g, r, and i images. We also perform simplified three-dimensional modeling of the light distribution in the stellar disks of edge-on galaxies from our sample. Our large sample is intended to be used for studying scaling relations in the stellar disks and bulges and for estimating parameters of the thick disks in different types of galaxies via the image stacking. In this paper, we present the sample selection procedure and general description of the sample.
- ID:
- ivo://CDS.VizieR/J/MNRAS/477/L50
- Title:
- Structure of the Upper Scorpius association
- Short Name:
- J/MNRAS/477/L50
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using new proper motion data from recently published catalogs, we revisit the membership of previously identified members of the Upper Scorpius association. We confirmed 750 of them as cluster members based on the convergent point method, compute their kinematic parallaxes and combined them with Gaia parallaxes to investigate the 3D structure and geometry of the association using a robust covariance method. We find a mean distance of 146+/-3+/-6pc and show that the morphology of the association defined by the brightest (and most massive) stars yields a prolate ellipsoid with dimensions of 74x38x32pc^3^, while the faintest cluster members define a more elongated structure with dimensions of 98x24x18pc^3^. We suggest that the different properties of both populations is an imprint of the star formation history in this region.
- ID:
- ivo://CDS.VizieR/J/A+A/509/A70
- Title:
- Study of an eclipsing binary in M31
- Short Name:
- J/A+A/509/A70
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The cosmic distance scale largely depends on distance determinations to galaxies of the Local Group. In this sense, the Andromeda galaxy (M31) is a key rung to better constrain the cosmic distance ladder. A project was started in 1999 to firmly establish a direct and accurate distance to M31 using eclipsing binaries (EBs). After the determination of the first direct distance to M31 from EBs, the second direct distance to an EB system is presented: M31V J00443610+4129194. Light and radial velocity curves were obtained and fitted to derive the masses and radii of the components. The acquired spectra were combined and disentangled to determine the temperature of the components. The analysis of the studied EB resulted in a distance determination to M31 of (m-M)0=24.30+/-0.11mag. This result, when combined with the previous distance determination to M31, results in a distance modulus of (m-M)0=24.36+/-0.08mag (744+/-33kpc), fully compatible with other distance determinations to M31. With an error of only project.
