- ID:
- ivo://CDS.VizieR/J/ApJ/817/112
- Title:
- NEOWISE/AllWISE high proper motion objects
- Short Name:
- J/ApJ/817/112
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Wide-field Infrared Survey Explorer (WISE) was reactivated in 2013 December (NEOWISE) to search for potentially hazardous near-Earth objects. We have conducted a survey using the first sky pass of NEOWISE data and the AllWISE catalog to identify nearby stars and brown dwarfs with large proper motions ({mu}_total_>~250mas/yr). A total of 20548 high proper motion objects were identified, 1006 of which are new discoveries. This survey has uncovered a significantly larger sample of fainter objects (W2>~13mag) than the previous WISE motion surveys of Luhman (2014, J/ApJ/781/4) and Kirkpatrick et al. (2014, J/ApJ/783/122). Many of these objects are predicted to be new L and T dwarfs based on near- and mid-infrared colors. Using estimated spectral types along with distance estimates, we have identified several objects that likely belong to the nearby solar neighborhood (d<25pc). We have followed up 19 of these new discoveries with near-infrared or optical spectroscopy, focusing on potentially nearby objects, objects with the latest predicted spectral types, and potential late-type subdwarfs. This subset includes six M dwarfs, five of which are likely subdwarfs, as well as eight L dwarfs and five T dwarfs, many of which have blue near-infrared colors. As an additional supplement, we provide 2MASS and AllWISE positions and photometry for every object found in our search, as well as 2MASS/AllWISE calculated proper motions.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/other/JDSO/15.434
- Title:
- New Binary Systems from Data of Gaia DR2
- Short Name:
- J/other/JDSO/15.
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The author describes the discovery of 4 new pairs of stars with almost identical proper motions and parallaxes (from Gaia DR2 data).
- ID:
- ivo://CDS.VizieR/J/A+A/590/A13
- Title:
- New candidate members in young associations
- Short Name:
- J/A+A/590/A13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The young associations offer us one of the best opportunities to study the properties of young stellar and sub-stellar objects and directly image planets thanks to their proximity (<200pc) and age (5-150Myr). However, many previous works have been limited to identifying the brighter, more active members (1Msun) due to photometric survey sensitivities limiting the detections of lower-mass objects. We search the field of view of 542 previously identified members of the young associations to identify wide / extremely wide (1000-100,000au in physical separation) companions. Methods. We have combined 2MASS near-infrared photometry (J, H, K) with proper motion values (from UCAC4, PPMXL, NOMAD) to identify companions in the field of view of known members. We collated further photometry and spectroscopy from the literature and conducted our own high-resolution spectroscopic observations for a sub-sample of candidate members. This complementary information allowed us to assess the efficiency of our method. We identified 84 targets (45:0.2-1.3M_{sun}_, 17:0.08-0.2M_{sun}_, 22:<0.08M_{sun}_) in our analysis, 10 of which have been identified from spectroscopic analysis in previous young association works. For 33 of these 84 we were able to further assess their membership using a variety of properties (X-ray emission, UV excess, H{alpha}, lithium and KI equivalent widths, radial velocities, and CaH indices). We derive a success rate of 76-88% for this technique based on the consistency of these properties. Once confirmed, the targets identified in this work would significantly improve our knowledge of the lower-mass end of the young associations. Additionally, these targets would make an ideal new sample for the identification and study of planets around nearby young stars. Given the predicted sub-stellar mass of the majority of these new candidate members and their proximity, high-contrast imaging techniques would facilitate the search for new low-mass planets.
- ID:
- ivo://CDS.VizieR/J/MNRAS/383/831
- Title:
- New DENIS nearby L and late-M dwarfs
- Short Name:
- J/MNRAS/383/831
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on new nearby L and late-M dwarfs (d_phot_<=30pc) discovered in our search for nearby ultracool dwarfs (I-J>=3.0, later than M8.0) in the Galactic plane (|b|<15{deg}) over 4800 deg^2^ in the Deep Near Infrared Survey of t he Southern Sky (DENIS) data base. We used late-M (>=M8.0), L and T dwarfs with accurate trigonometric parallaxes to calibrate the M_J_ versus I-J colour-luminosity relation. The resulting photometric distances have standard errors of ~15 per cent, which we used to select candidates dphot <=30pc. We measured proper motions from multi-epoch images found in the public archives ALADIN, DSS, 2MASS and DENIS, with at least three distinct epochs and time baselines of 10-21yr. We then used the Maximum Reduced Proper Motion method to select 28 candidates as ultracool dwarfs (M8.0-L8.0) and to reject one as a distant red star. Our low-resolution optical spectra confirmed that 26 were indeed ultracool dwarfs, with spectral types from M8.0 to L5.5. Two contaminants and one rejected by the maximum reduced proper motion cut-off were all reddened F-K main sequence stars. 20 of these 26 ultracool dwarfs are new nearby ultracool dwarf members, three L dwarfs within 15pc with one L3.5 at only ~10pc.
- ID:
- ivo://CDS.VizieR/J/MNRAS/496/2021
- Title:
- New Galactic open clusters
- Short Name:
- J/MNRAS/496/2021
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of 25 new open clusters resulting from a search in dense low galactic latitude fields. We also provide, for the first time, structural and astrophysical parameters for the new findings and 34 other recently discovered open clusters using Gaia DR2 data. The candidates were confirmed by jointly inspecting the vector point diagrams and spatial distribution. The discoveries were validated by matching near known objects and comparing their mean astrometric parameters with the available literature. A decontamination algorithm was applied to the three-dimensional astrometric space to derive membership likelihoods for clusters stars. By rejecting stars with low membership likelihoods, we built decontaminated colour-magnitude diagrams and derived the clusters astrophysical parameters by isochrone fitting. The structural parameters were also derived by King-profile fittings over the stellar distributions. The investigated clusters are mainly located within 3kpc from the Sun, with ages ranging from 30Myr to 3.2Gyr and reddening limited to E(B-V)=2.5. On average, our cluster sample presents less concentrated structures than Gaia DR2 confirmed clusters, since the derived core radii are larger while the tidal radii are not significantly different. Most of them are located in the IV quadrant of the Galactic disc at low latitudes, therefore they are immersed in dense fields characteristic of the inner Milky Way.
- ID:
- ivo://CDS.VizieR/J/A+A/440/403
- Title:
- 109 new Galactic open clusters
- Short Name:
- J/A+A/440/403
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a list of 130 Galactic Open Clusters, found in the All-Sky Compiled Catalogue of 2.5 Million Stars (ASCC-2.5). For these clusters we determined a homogeneous set of astrophysical parameters such as size, membership, motion, distance and age. In a previous work (Cat. J/A+A/438/1163), 520 already-known open clusters out of a sample of 1700 clusters from the literature were confirmed in the ASCC-2.5 using independent, objective methods. Using these methods the whole sky was systematically screened for new clusters. The newly detected clusters show the same distribution over the sky as the known ones. It is found that without the a priori knowledge about existing clusters our search lead to clusters which are, on average, brighter, have more members and cover larger angular radii than the 520 previously-known ones.
- ID:
- ivo://CDS.VizieR/J/AJ/129/413
- Title:
- New high proper motion stars (-90<DE< -47)
- Short Name:
- J/AJ/129/413
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of 141 new high proper motion systems ({mu}>=0.4"/yr) in the southern sky (DE=-90 to -47{deg}) brighter than UKST plate R_59F_=16.5 via our SuperCOSMOS-RECONS search. When combined with the nine systems having {mu}>=1.0"/yr and/or late spectral type from the initial phases of this effort, we find that 73 of the 150 total systems are moving faster than 0.5"/yr and are therefore new members of the classic Luyten Half-Second sample. These constitute a 21% increase in the sample of stars with {mu}>=0.5"/yr in the declination region searched, thereby comprising an important addition to this long-neglected region of the sky. Distance estimates are provided for the entire sample, based on a combination of photographic plate magnitudes and Two Micron All Sky Survey photometry, using the relations recently presented by Hambly et al. for the presumed main-sequence stars. Three systems are anticipated to be within 10pc, and an additional 15 are within 25pc. Nine of these 18 nearby systems have proper motions falling between 0.4"/yr and 0.6"/yr, hinting at a large population of nearby stars with fast, but not extremely high, proper motions that have not been thoroughly investigated.
- ID:
- ivo://CDS.VizieR/J/AJ/130/1658
- Title:
- New high proper motion stars (-47<{delta}<00)
- Short Name:
- J/AJ/130/1658
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of 152 new high proper motion systems ({mu}>=0.4"/yr) in the southern sky ({delta}=-47{deg} to 00{deg}) brighter than UKST plate R_59F_=16.5 via our SuperCOSMOS-RECONS (SCR) search. This paper complements Paper XII (2005, Cat. <J/AJ/129/413>) in the Solar Neighborhood series, which covered the region from {delta}=-90{deg} to -47{deg} and discussed all 147 new systems from the southernmost phase of the search. Among the total of 299 systems from both papers, there are 148 (71 in Paper XII (2005, Cat. <J/AJ/129/413>), 77 in this paper) new systems moving faster than 0.5"/yr that are additions to the classic Luyten Half Second sample (1979, Cat. <I/87>). These constitute an 8% increase in the sample of all stellar systems with {mu}>=0.5"/yr in the southern sky.
- ID:
- ivo://CDS.VizieR/J/AJ/125/1598
- Title:
- New high proper motion stars in the northern sky
- Short Name:
- J/AJ/125/1598
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We define an enhanced spectral classification scheme for M dwarf stars and use it to derive spectral classification of 104 northern stars with proper motions larger than 0.5"/yr that we discovered in a survey of high proper motion stars at low Galactic latitudes. The final tally is as follows: 54 M dwarfs, 25 sdK and sdM subdwarfs, 14 esdK and esdM extreme subdwarfs, and 11 DA and DC white dwarfs. Among the most interesting cases, we find one star to be the coolest subdwarf ever reported (LSR 2036+5059, with spectral type sdM7.5), a new M9.0 dwarf only about 6 pc distant (LSR 1835+3259), and a new M6.5 dwarf only 7 pc from the Sun (LSR 2124+4003). Spectroscopic distances suggests that 27 of the M dwarfs, three of the white dwarfs, and one of the subdwarfs (LSR 2036+5059) are within 25 pc of the Sun, making them excellent candidates for inclusion in the solar neighborhood census. Estimated sky-projected velocities suggest that most of our subdwarfs and extreme subdwarfs have halo kinematics. We find that several white dwarfs and nonmetal-poor M dwarfs also have kinematics consistent with the halo, and we briefly discuss their possible origin.
- ID:
- ivo://CDS.VizieR/J/ApJS/150/455
- Title:
- New HIP-based parallaxes for 424 faint stars
- Short Name:
- J/ApJS/150/455
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 424 common proper-motion companions to Hipparcos stars with good (>3{sigma}) parallaxes, thereby effectively providing new parallaxes for these companions. Compared with typical stars in the Hipparcos catalog, these stars are substantially dimmer. The catalog includes 20 white dwarfs and an additional 29 stars with M_V_>14, the great majority of the latter being M dwarfs.
