- ID:
- ivo://CDS.VizieR/J/AJ/156/271
- Title:
- The stellar membership of the Taurus SFR
- Short Name:
- J/AJ/156/271
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The high-precision astrometry from the second data release of the Gaia mission (Cat. I/345) has made it possible to greatly improve the census of members of nearby clusters and associations. I have applied the Gaia data to the Taurus star-forming region, refining the sample of known members and identifying candidates for undiscovered members. The resulting samples of members and candidates provide the best constraints to date on the distribution of ages and the initial mass function (IMF) in Taurus. Several studies over the last 30 years have proposed the existence of a population of older stars (>~10 Myr) that is associated with the Taurus clouds. The data from Gaia demonstrate that such a population does not exist. Meanwhile, previous IMF estimates for small fields surrounding the Taurus aggregates have exhibited a surplus of K7-M0 stars (0.7-0.8 M_{sun}_) relative to star-forming clusters such as IC 348 and the Orion Nebula Cluster. However, that difference disappears when the new census of the entire region is considered, which should be complete for spectral types earlier than M6-M7 at A_J_<1. Thus, there is little variation in the stellar IMF across the 3-4 orders of magnitude in stellar density that are present in nearby star-forming regions. Finally, I note that the proper motions of two previously known members, KPNO 15 and 2MASS J04355209+2255039, indicate that they may have been ejected from the same location within the L1536 cloud ~7200 years ago.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/156/102
- Title:
- The TESS Input Catalog and Candidate Target List
- Short Name:
- J/AJ/156/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Transiting Exoplanet Survey Satellite (TESS) will be conducting a nearly all-sky photometric survey over two years, with a core mission goal to discover small transiting exoplanets orbiting nearby bright stars. It will obtain 30 minute cadence observations of all objects in the TESS fields of view, along with two-minute cadence observations of 200000-400000 selected stars. The choice of which stars to observe at the two-minute cadence is driven by the need to detect small transiting planets, which leads to the selection of primarily bright, cool dwarfs. We describe the catalogs assembled and the algorithms used to populate the TESS Input Catalog (TIC), including plans to update the TIC with the incorporation of the Gaia second data release (Cat. I/345) in the near future. We also describe a ranking system for prioritizing stars according to the smallest transiting planet detectable, and assemble a Candidate Target List (CTL) using that ranking. We discuss additional factors that affect the ability to photometrically detect and dynamically confirm small planets, and we note additional stellar populations of interest that may be added to the final target list. The TIC is available on the STScI MAST server, and an enhanced CTL is available through the Filtergraph data visualization portal system at the URL http://filtergraph.vanderbilt.edu/tess_ctl.
- ID:
- ivo://CDS.VizieR/III/250
- Title:
- The VIMOS VLT deep survey (VVDS-DEEP)
- Short Name:
- III/250
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+A/572/A116
- Title:
- The VISTA Carina Nebula Survey
- Short Name:
- J/A+A/572/A116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Carina Nebula is one of the most massive and active star-forming regions in our Galaxy and has been studied with numerous multiwavelength observations in the past five years. However, most of these studies were restricted to the inner parts (<=1 square-degree) of the nebula, and thus covered only a small fraction of the whole cloud complex. Our aim was to conduct a near-infrared survey that covers the full spatial extent (~5 square-degrees) of the Carina Nebula complex and is sensitive enough to detect all associated young stars through extinctions of up to A_V_~~6mag. We used the 4m Visible and Infrared Survey Telescope for Astronomy (VISTA) of ESO to map an area of 6.7 square-degrees around the Carina Nebula in the near-infrared J-, H-, Ks-bands.
- ID:
- ivo://CDS.VizieR/II/359
- Title:
- The VISTA Hemisphere Survey (VHS) catalog DR4.1
- Short Name:
- II/359
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The first Galactic and extragalactic results from the VISTA Hemisphere Survey (VHS) are presented. The aim of the VHS is to carry out a near-infrared survey which, when combined with other VISTA public surveys, will result in coverage of the whole southern celestial hemisphere (~20000deg^2^) to a depth 30 times fainter than the Two Micron All Sky Survey in at least two wavebands (J and Ks). The VHS vision includes a deep optical survey over the same area and this is now being realised with the VST surveys and the Dark Energy Survey, which has recently started. A summary of the survey progress is presented, with some follow-up results on low-mass stars and high-redshift quasars.
- ID:
- ivo://CDS.VizieR/II/367
- Title:
- The VISTA Hemisphere Survey (VHS) catalog DR5
- Short Name:
- II/367
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- This multi-band source catalogue provides aperture photometry in four near infrared broad-band filters: Y, J, H and Ks for almost 1.4 billion detections. The total coverage of the VHS survey is almost 17000 square degrees in the South Hemisphere.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/21
- Title:
- The VMC survey. XIX. Classical Cepheids in SMC
- Short Name:
- J/ApJS/224/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The "VISTA near-infrared YJK_s_ survey of the Magellanic Clouds System" (VMC) is collecting deep K_s_-band time-series photometry of pulsating variable stars hosted by the two Magellanic Clouds and their connecting Bridge. In this paper, we present Y, J, K_s_ light curves for a sample of 4172 Small Magellanic Cloud (SMC) Classical Cepheids (CCs). These data, complemented with literature V values, allowed us to construct a variety of period-luminosity (PL), period-luminosity-color (PLC), and period-Wesenheit (PW) relationships, which are valid for Fundamental (F), First Overtone (FO), and Second Overtone (SO) pulsators. The relations involving the V, J, K_s_ bands are in agreement with their counterparts in the literature. As for the Y band, to our knowledge, we present the first CC PL, PW, and PLC relations ever derived using this filter. We also present the first near-infrared PL, PW, and PLC relations for SO pulsators to date. We used PW(V, K_s_) to estimate the relative SMC-LMC distance and, in turn, the absolute distance to the SMC. For the former quantity, we find a value of {Delta}{mu}=0.55+/-0.04mag, which is in rather good agreement with other evaluations based on CCs, but significantly larger than the results obtained from older population II distance indicators. This discrepancy might be due to the different geometric distributions of young and old tracers in both Clouds. As for the absolute distance to the SMC, our best estimates are {mu}_SMC_=19.01+/-0.05mag and {mu}_SMC_=19.04+/-0.06mag, based on two distance measurements to the LMC which rely on accurate CC and eclipsing Cepheid binary data, respectively.
- ID:
- ivo://CDS.VizieR/J/ApJ/864/11
- Title:
- The VVV Variables (V^4^) catalog
- Short Name:
- J/ApJ/864/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Time-varying phenomena are one of the most substantial sources of astrophysical information, and their study has led to many fundamental discoveries in modern astronomy. We have developed an automated tool to search for and analyze variable sources in the near-infrared Ks band using the data from the VISTA Variables in the Via Lactea (VVV) ESO Public Large Survey. This process relies on the characterization of variable sources using different variability indices calculated from time series generated with point-spread function (PSF) photometry of sources under analysis. In particular, we used two main indices, the total amplitude {Delta}Ks and the eta index {eta}, to identify variable sources. Once the variable objects are identified, periods are determined with generalized Lomb-Scargle periodograms and the information potential metric. Variability classes are assigned according to a compromise between comparisons with VVV templates and the period of the variability. The automated tool is applied on VVV tiles d001 and d002 and led to the discovery of 200 variable sources. We detected 70 irregular variable sources and 130 periodic ones. In addition, nine open-cluster candidates projected in the region are analyzed, and the infrared variable candidates found around these clusters are further scrutinized by cross-matching their locations against emission star candidates from VPHAS+ survey H{alpha} color cuts.
3019. The WIRED survey. II.
- ID:
- ivo://CDS.VizieR/J/ApJS/197/38
- Title:
- The WIRED survey. II.
- Short Name:
- J/ApJS/197/38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- With the launch of the Wide-field Infrared Survey Explorer (WISE), a new era of detecting planetary debris and brown dwarfs (BDs) around white dwarfs (WDs) has begun with the WISE InfraRed Excesses around Degenerates (WIRED) Survey. The WIRED Survey is sensitive to substellar objects and dusty debris around WDs out to distances exceeding 100pc, well beyond the completeness level of local WDs. In this paper, we present a cross-correlation of the preliminary Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) WD catalog between the WISE, Two-Micron All Sky Survey (2MASS), UKIRT Infrared Deep Sky Survey (UKIDSS), and SDSS DR7 photometric catalogs. From ~18000 input targets, there are WISE detections comprising 344 "naked" WDs (detection of the WD photosphere only), 1020 candidate WD+M dwarf binaries, 42 candidate WD+BD systems, 52 candidate WD+dust disk systems, and 69 targets with indeterminate infrared excess. We classified all of the detected targets through spectral energy distribution model fitting of the merged optical, near-IR, and WISE photometry. Some of these detections could be the result of contaminating sources within the large (~6") WISE point-spread function; we make a preliminary estimate for the rates of contamination for our WD+BD and WD+disk candidates and provide notes for each target of interest.
- ID:
- ivo://CDS.VizieR/J/ApJS/234/23
- Title:
- The WISE AGN candidates catalogs
- Short Name:
- J/ApJS/234/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two large catalogs of active galactic nucleus (AGN) candidates identified across 30,093deg^2^ of extragalactic sky from the Wide-field Infrared Survey Explorer's AllWISE Data Release. Both catalogs are selected purely using the Wide-field Infrared Survey Explorer (WISE) W1 and W2 bands. The R90 catalog consists of 4,543,530 AGN candidates with 90% reliability, while the C75 catalog consists of 20,907,127 AGN candidates with 75% completeness. These reliability and completeness figures were determined from a detailed analysis of UV- to near-IR spectral energy distributions of ~10^5^ sources in the 9deg^2^ Bootes field. The AGN selection criteria are based on those of Assef+ (2013, J/ApJ/772/26) recalibrated to the AllWISE data release. We provide a detailed discussion of potential artifacts and excise portions of the sky close to the Galactic Center, Galactic Plane, nearby galaxies, and other expected contaminating sources. These catalogs are expected to enable a broad range of science, and we present a few illustrative cases. From the R90 sample, we identify 45 highly variable AGNs lacking radio counterparts in the FIRST survey. One of these sources, WISEA J142846.71+172353.1, is a changing-look quasar at z=0.104, which has changed from having broad H{alpha} to being a narrow-lined AGN. We characterize our catalogs by comparing them to large, wide-area AGN catalogs in the literature. We identify four ROSAT X-ray sources that are each matched to three WISE-selected AGNs in the R90 sample within 30". Spectroscopy reveals that one of these systems, 2RXS J150158.6+691029, consists of a triplet of quasars at z=1.133+/-0.004, suggestive of a rich group or forming galaxy cluster.
