- ID:
- ivo://CDS.VizieR/J/AcA/50/221
- Title:
- Astrometry of variable stars in M 3
- Short Name:
- J/AcA/50/221
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present identification and astrometry of all previously known or suspected variables along with the discovery of six new variables in the globular cluster M3. The number of the catalogued variables increased to 274 by including all the confirmed, previously known variables and the new discoveries. The precise and homogeneous astrometry, as well as the clarification of misapprehensions in the preceding identifications are done by using overlapping fields from a wide-field Schmidt-camera, 1-m RCC telescope, and HST archive observations from the center of the cluster. The astrometric positions can serve as a direct input to any photometry which needs the accurate centers of the variables.
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- ID:
- ivo://CDS.VizieR/J/other/NewA/36.70
- Title:
- Astrometry of 3 vdBH open clusters
- Short Name:
- J/other/NewA/36.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of a study that combines photometry and astrometry for the open clusters vdB80, vdB85 and vdB130. We apply a model which analyses the proper motion distribution and the stellar density to find the kinematic parameters and stellar membership in the region of the mentioned open clusters. The astrometric data are obtained from UCAC4 catalogue.
- ID:
- ivo://CDS.VizieR/J/AJ/161/133
- Title:
- Astrometry & photometry for CMa R1 members
- Short Name:
- J/AJ/161/133
- Date:
- 09 Mar 2022 22:00:00
- Publisher:
- CDS
- Description:
- An exotic environment surrounds the young stellar groups associated with the Canis Major (CMa) OB1/R1 region, which probably was formed under feedback from at least three supernova events having occurred a few million years ago. We use astrometric data from the Gaia-DR2 to confirm the membership of the stars in CMa R1, based on proper motion and parallax, which revealed 514 new members and candidates. The mean age of 5Myr estimated from the color-magnitude diagram characterizes the sources as likely pre-main-sequence candidates. In total, a sample of 694 stars detected with the T80-South telescope was analyzed according to different color-color diagrams, which were compared with theoretical colors from evolutionary models, aiming to reveal the objects that exhibit color excess due to accretion processes. Accretion and magnetic activity were also explored on the basis of empirical flux-flux relation, such as F660 and F861 that are related to H{alpha} and CaII triplet emission, respectively. A low fraction (~3%) of the sample have H{alpha} excess and other colors expected for stars exhibiting chromospheric activity. The number of Class I and Class II objects, identified by the infrared (Wide-field Infrared Survey Explorer) colors, indicates a disk fraction of ~6%, which is lower than that expected for stellar clusters with a similar age. Such a large sample of objects associated with CMa R1 without evidences of circumstellar accretion can be interpreted as a lack of disk-bearing stars, unusual for young star-forming regions. However, this may be explained as the result of supernova events.
- ID:
- ivo://CDS.VizieR/J/AJ/154/147
- Title:
- Astrometry&photometry for late-type dwarfs&subdwarfs
- Short Name:
- J/AJ/154/147
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New, updated, and/or revised CCD parallaxes determined with the Strand Astrometric Reflector at the Naval Observatory Flagstaff Station are presented. Included are results for 309 late-type dwarf and subdwarf stars observed over the 30+ years that the program operated. For 124 of the stars, parallax determinations from other investigators have already appeared in the literature and we compare the different results. Also included here are new or updated VI photometry on the Johnson-Kron-Cousins system for all but a few of the faintest targets. Together with 2MASS JHK_s_ near-infrared photometry, a sample of absolute magnitude versus color and color versus color diagrams are constructed. Because large proper motion was a prime criterion for targeting the stars, the majority turn out to be either M-type subdwarfs or late M-type dwarfs. The sample also includes 50 dwarf or subdwarf L-type stars, and four T dwarfs. Possible halo subdwarfs are identified in the sample based on tangential velocity, subluminosity, and spectral type. Residuals from the solutions for parallax and proper motion for several stars show evidence of astrometric perturbations.
- ID:
- ivo://CDS.VizieR/J/AJ/155/252
- Title:
- Astrometry & photometry of dwarf carbon stars
- Short Name:
- J/AJ/155/252
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Parallaxes are presented for a sample of 20 nearby dwarf carbon stars. The inferred luminosities cover almost two orders of magnitude. Their absolute magnitudes and tangential velocities confirm prior expectations that some originate in the Galactic disk, although more than half of this sample are halo stars. Three stars are found to be astrometric binaries, and orbital elements are determined; their semimajor axes are 1-3 au, consistent with the size of an AGB mass-transfer donor star.
- ID:
- ivo://CDS.VizieR/J/AJ/162/14
- Title:
- Astrometry & radial velocity, Alpha Centauri system
- Short Name:
- J/AJ/162/14
- Date:
- 14 Mar 2022 06:46:54
- Publisher:
- CDS
- Description:
- Alpha Centauri A is the closest solar-type star to the Sun and offers the best opportunity to find and ultimately to characterize an Earth-sized planet located in its habitable zone. Here, we describe initial results from an Atacama Large Millimeter/submillimeter Array (ALMA) program to search for planets in the {alpha} Cen AB system using differential astrometry at millimeter wavelengths. Our initial results include new absolute astrometric measurements of the proper motion, orbital motion and parallax of the {alpha} Cen system. These lead to an improved knowledge of the physical properties of both {alpha} Cen A and B. Our estimates of ALMA's relative astrometric precision suggest that we will ultimately be sensitive to planets of a few tens of Earth mass in orbits from 1 to 3au, where stable orbits are thought to exist.
- ID:
- ivo://CDS.VizieR/III/280
- Title:
- Astron low resolution UV spectra
- Short Name:
- III/280
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Astron was a Soviet spacecraft launched on 23 March 1983, and it was operational for eight years as the largest ultraviolet space telescope during its lifetime. Astron's payload consisted of an 80 cm ultraviolet telescope Spica and an X-ray spectroscope. We present 159 low resolution spectra of stars obtained during the Astron space mission (Tables 4, 5; hereafter table numbers in Boyarchuk et al. 1994 are given). Table 4 (observational log, logs.dat) contains data on 142 sessions for 90 stars (sorted in ascending order of RA), where SED was obtained by scanning method, and then data on 17 sessions for 15 stars (also sorted in ascending order of RA), where multicolor photometry was done. Kilpio et al. (2016, Baltic Astronomy 25, 23) presented results of the comparison of Astron data to the modern UV stellar data, discussed Astron precision and accuracy, and made some conclusions on potential application areas of these data. Also 34 sessions of observations of 27 stellar systems (galaxies and globular clusters) are presented. Observational log was published in Table 10 and data were published in Table 11, respectively. Also 16 sessions of observations of 12 nebulae (Table 12 for observational log and Table 13 for data themselves) are presented. Background radiation intensity data (Table 14) are presented in Table 15. At last, data on comets are presented in different forms. We draw your attention that observational data for stars, stellar systems, nebulae and comets are expressed in log [erg/s/cm^2/A], while for comets data 10E-13 erg/s/cm^2/A units are used, hydroxyl band photometric data for comets are expressed in log [erg/s/cm^2], and for the background data it is radiation intensity expressed in log [erg/s/cm^2/A/sr]. Scanned (PDF version of) Boyarchuk et al. (1994) book is available at http://www.inasan.ru/~astron/astron.pdf
- ID:
- ivo://CDS.VizieR/J/ApJ/842/6
- Title:
- Astro-photometric catalog of the core of NGC 5139
- Short Name:
- J/ApJ/842/6
- Date:
- 16 Nov 2021 13:43:59
- Publisher:
- CDS
- Description:
- We have constructed the most comprehensive catalog of photometry and proper motions ever assembled for a globular cluster (GC). The core of {omega}Cen (NGC 5139) has been imaged over 650 times through WFC3's UVIS and IR channels for the purpose of detector calibration. There exist from 4 to over 60 exposures through each of 26 filters stretching continuously from F225W in the UV to F160W in the infrared. Furthermore, the 11yr baseline between these data and a 2002 ACS survey has allowed us to more than double the proper-motion accuracy and triple the number of well-measured stars compared to our previous groundbreaking effort. This totally unprecedented complete spectral coverage of over 470000 stars within the cluster's core, from the tip of the red giant branch down to the white dwarfs, provides the best astro-photometric observational database yet to understand the multiple-population phenomenon in any GC. In this first paper of the series, we describe in detail the data-reduction processes and deliver the astro-photometric catalog to the astronomical community.
- ID:
- ivo://CDS.VizieR/J/MNRAS/396/1231
- Title:
- Astrophotometric catalogue of NGC 891
- Short Name:
- J/MNRAS/396/1231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep VI images obtained with the Advanced Camera for Surveys on board the Hubble Space Telescope, covering three fields in the north-east side of the edge-on disc galaxy NGC 891. The observed fields span a wide range of galactocentric distances along the eastern minor axis, extending from the plane of the disc to 12kpc, and out to ~25kpc along the major axis. The photometry of individual stars reaches ~2.5mag below the tip of the red giant branch. We use the astrophotometric catalogue to probe the stellar content and metallicity distribution across the thick disc and spheroid of NGC 891.
- ID:
- ivo://CDS.VizieR/J/AZh/87/760
- Title:
- Astrophysical catalog of clusters of galaxies
- Short Name:
- J/AZh/87/760
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog of rich clusters of galaxies contains information about the astrometric and physical characteristics of the 213 clusters of galaxies and data about evidences of the presence of cooling flows and filaments in selected clusters. The catalog lists also the references to the sources of the data.
