- ID:
- ivo://CDS.VizieR/J/A+A/595/A22
- Title:
- Nine new open clusters within 500pc from the Sun
- Short Name:
- J/A+A/595/A22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- One of the results of the Milky Way Star Clusters (MWSC) survey was the detection of a slight under-density of old (ca. 1Gyr) clusters within the nearest kilo-parsec from the Sun. This under-density may be due to an ineffectiveness in the detection of larger structures with lower surface brightness. We report on our attempts to reveal such clusters. We derived proper motions from a combination of Tycho-2 with URAT1, and obtained a mean precision of about 1.4mas/yr per co-ordinate for 1.3 million stars north of -20{deg} declination. We cut the sky into narrow proper motion slices and searched for spatial over-densities of stars in each slice. We then examined stars from over-densities in optical and near-infrared colour-magnitude diagrams to determine if they are compatible with isochrones of a cluster. We estimated the field star contamination using our data and the Besancon Galactic model. We detected nine hitherto unknown open clusters in the vicinity of the Sun with ages between 70Myr and 1Gyr, and distances between 200 and 500pc.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/437/3603
- Title:
- NIR proper motion catalogue from UKIDSS-LAS
- Short Name:
- J/MNRAS/437/3603
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The United Kingdom Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS) began in 2005, with the start of the UKIDSS programme as a 7 year effort to survey roughly 4000deg^2^ at high Galactic latitudes in Y, J, H and K bands. The survey also included a significant quantity of two epoch J band observations, with an epoch baseline greater than 2 years to calculate proper motions. We present a near-infrared proper motion catalogue for the 1500deg^2^ of the two epoch LAS data, which includes 135625 stellar sources and a further 88324 with ambiguous morphological classifications, all with motions detected above the 5{sigma} level. We developed a custom proper motion pipeline which we describe here. Our catalogue agrees well with the proper motion data supplied for a 300deg^2^ subset in the current Wide Field Camera Science Archive (WSA) 10th data release (DR10) catalogue, and in various optical catalogues, but it benefits from a larger matching radius and hence a larger upper proper motion detection limit. We provide absolute proper motions, using LAS galaxies for the relative to absolute correction. By using local second-order polynomial transformations, as opposed to linear transformations in the WSA, we correct better for any local distortions in the focal plane, not including the radial distortion that is removed by the UKIDSS pipeline. We present the results of proper motion searches for new brown dwarfs and white dwarfs. We discuss 41 sources in the WSA DR10 overlap with our catalogue with proper motions >300mas/yr, several of which are new detections. We present 15 new candidate ultracool dwarf binary systems.
- ID:
- ivo://CDS.VizieR/J/ApJS/190/100
- Title:
- NIR proper motion survey using 2MASS
- Short Name:
- J/ApJS/190/100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted a 4030deg^2^ near-infrared proper motion survey using multi-epoch data from the Two Micron All-Sky Survey (2MASS). We find 2778 proper motion candidates, 647 of which are not listed in SIMBAD. After comparison to Digitized Sky Survey images, we find that 107 of our proper motion candidates lack counterparts at B, R, and I bands and are thus 2MASS-only detections. We present results of spectroscopic follow-up of 188 targets that include the infrared-only sources along with selected optical-counterpart sources with faint reduced proper motions or interesting colors. We also establish a set of near-infrared spectroscopic standards with which to anchor near-infrared classifications for our objects. Among the discoveries are six young field brown dwarfs, five "red L" dwarfs, three L-type subdwarfs, twelve M-type subdwarfs, eight "blue L" dwarfs, and several T dwarfs. We further refine the definitions of these exotic classes to aid future identification of similar objects. We examine their kinematics and find that both the "blue L" and "red L" dwarfs appear to be drawn from a relatively old population.
- ID:
- ivo://CDS.VizieR/J/ApJS/222/2
- Title:
- NIR sources in the northeastern part of LMC
- Short Name:
- J/ApJS/222/2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a near-infrared band-merged photometric and polarimetric catalog for the 39'x69' fields in the northeastern part of the Large Magellanic Cloud (LMC), which were observed using SIRPOL, an imaging polarimeter of the InfraRed Survey Facility. This catalog lists 1858 sources brighter than 14mag in the H band with a polarization signal-to-noise ratio greater than three in the J, H, or K_s_ bands. Based on the relationship between the extinction and the polarization degree, we argue that the polarization mostly arises from dichroic extinctions caused by local interstellar dust in the LMC. This catalog allows us to map polarization structures to examine the global geometry of the local magnetic field, and to show a statistical analysis of the polarization of each field to understand its polarization properties. In the selected fields with coherent polarization position angles, we estimate magnetic field strengths in the range of 3-25{mu}G using the Chandrasekhar-Fermi method. This implies the presence of large-scale magnetic fields on a scale of around 100 parsecs. When comparing mid- and far-infrared dust emission maps, we confirmed that the polarization patterns are well aligned with molecular clouds around the star-forming regions.
415. NLTT Catalogue
- ID:
- ivo://CDS.VizieR/I/98A
- Title:
- NLTT Catalogue
- Short Name:
- I/98A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The NLTT catalog is a collection of stars with proper motions exceeding 0.18"/yr found by Luyten and his coworkers. The First Supplement to the NLTT catalog is the result of continued plate analysis and contains data for 398 stars with proper motions greater than 0.179"/yr. A number of corrections to the data in the published catalog have been entered in the machine-readable version, including the omission of duplicate entries and those stars later determined to show no motion. The catalog contains, in addition to the proper motions, 1950 equatorial coordinates, a flag indicating the approximate accuracy of the positions, estimated red and photographic magnitudes, spectral types, and flags indicating a change from the published volume and the presence of the star in the supplement.
- ID:
- ivo://CDS.VizieR/J/ApJS/239/26
- Title:
- NOFS astrometric measurements for distant WDs
- Short Name:
- J/ApJS/239/26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents new trigonometric parallaxes and proper motions for 214 stars. The measurements were made at the US Naval Observatory Flagstaff Station between 1989 and 2017, and the average uncertainty in the parallax values is 0.6mas. We find good agreement with Gaia Data Release 2 measurements for the stars in common, although there may be a small systematic offset similar to what has been found by other investigators. The sample is matched to catalogs and the literature to create a photometric data set that spans the ultraviolet to the mid-infrared. New mid-infrared photometry is obtained for 19 stars from archived Spitzer mosaics. New optical spectroscopy is presented for seven systems and additional spectra were obtained from the literature. We identify a subsample of 179 white dwarfs (WDs) at distances of 25-200pc. Their spectral energy distributions (SEDs) are analyzed using model atmospheres. The models reproduce the entire flux-calibrated SED very well and provide the atmospheric chemical composition, temperature, surface gravity, mass, and cooling age of each WD. Twenty-six WDs are newly classified, and 12 systems are presented as candidate unresolved binaries. We confirm one WD+red dwarf system and identify two WDs as candidate dust disk systems. Twelve old and high-velocity systems are identified as candidate thick disk or halo objects. The WDs in the sample generally have Galactic disk-like ages of <8Gyr and masses close to the canonical 0.6M_{sun}_.
417. NOMAD Catalog
- ID:
- ivo://CDS.VizieR/I/297
- Title:
- NOMAD Catalog
- Short Name:
- I/297
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Naval Observatory Merged Astrometric Dataset (NOMAD) contains astrometric and photometric data for over 1 billion stars derived from the Hipparcos (I/239), Tycho-2 (I/259), UCAC2 (I/289), and USNO-B1.0 (I/284) catalogs for astrometry and optical photometry, supplemented by 2MASS (II/246) near-infrared photometry. For each unique star the "best" astrometric and photometric data are chosen from the source catalogs and merged into a single dataset. A sequence of priorities is followed and NOMAD contains flags to identify the source catalogs and gives cross-reference identifications. This first release of NOMAD is not a compiled catalog; that is, if a star is identified in more than 1 of the above mentioned catalogs, only 1 catalog entry is chosen. Thus the local and global systematic errors of the various source catalogs will be present in this version of NOMAD. All source catalogs astrometric data are on the International Celestial Reference System within the limitations of the source catalogs. For more information, see https://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/nomad A dedicated remote query program can be downloaded from http://cdsweb.u-strasbg.fr/doc/cdsclient.html
- ID:
- ivo://CDS.VizieR/J/AJ/124/1190
- Title:
- Northern high proper motion stars in DSS
- Short Name:
- J/AJ/124/1190
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted a systematic search for high proper motion stars in the Digitized Sky Survey, in the area of the sky north of -2.8 degrees in declination and within 25 degrees of the Galactic plane. Using the SUPERBLINK software, a powerful automated blink comparator developed by us, we have identified 601 stars in the magnitude range 9<r<20 with proper motions in the range 0.5"/yr<{mu}<2.0"/yr which have not been observed with the Hipparcos satellite. Among those, we recovered 460 stars previously listed in Luyten's proper motion catalogs (LHS <I/87>, NLTT <I/98>) and discovered 141 new high proper motion stars, ranging in magnitude from R=13.0 to R=19.8. Only nine stars from the Luyten catalogs that were not observed by Hipparcos could not be recovered with SUPERBLINK: three had proper motions larger than the search limit of the code ({mu}>2.0"/yr), and five were missed because they were either too bright for SUPERBLINK to handle or they are in the immediate proximity of very bright stars. Only one of Luyten's stars (LHS 1657) could not be recovered at all, even by visual inspection of the POSS plates, and is now suspected to be bogus. The very high success rate in the recovery by SUPERBLINK of faint Luyten stars suggests that our new survey of high proper motion stars is at least 99% complete for stars with proper motions 0.5"/yr<{mu}<2.0"/yr down to R=19. This paper includes a list of positions, proper motions, magnitudes, and finder charts for all the new high proper motion stars.
- ID:
- ivo://CDS.VizieR/I/293
- Title:
- NPM2 Cross-Identifications
- Short Name:
- I/293
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Lick NPM2 Catalog provides absolute proper motions, positions, and photographic photometry, measured in the Lick Northern Proper Motion (NPM) program, for 232,062 stars in the magnitude range 8<B<18, covering the sky within the Milky Way north of -23deg declination. The NPM2 Cross-Identifications file provides 46,887 cross-identifications between the NPM2 Catalog numbers and star names, stellar type classifications, and publication references. These additional data, extracted from Klemola's Lick Input Catalog of Special Stars (ICSS), facilitate many practical uses of the NPM2 Catalog. Five Appendices to the NPM2 Catalog provide references, footnotes, and other useful information. This "ReadMe" file explains the file formats. Detailed documentation is given in the file "npm2cros.txt".
- ID:
- ivo://CDS.VizieR/I/214
- Title:
- NPM1 Cross-Identifications and Appendices
- Short Name:
- I/214
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The NPM1 Catalog provides absolute proper motions, positions, and photographic photometry, measured in the Lick Northern Proper Motion (NPM) program, for some 149,000 stars in the magnitude range 8<B<18mag, covering the sky outside the Milky Way north of -23{deg} declination. The NPM1 Cross-Identifications file provides some 42,000 cross-identifications between the NPM1 Catalog numbers and star names, stellar type classifications, and publication references. These additional data, extracted from the Lick Input Catalog of Special Stars, facilitate many practical uses of the NPM1 Catalog. Six Appendices to the NPM1 Catalog provide references, footnotes, and other useful information.
