- ID:
- ivo://CDS.VizieR/VI/145
- Title:
- ASC Gaia Attitude Star Catalog
- Short Name:
- VI/145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ASC is a compilation produced for the Gaia mission. We have combined data from the following catalogs or datasets to produce a homogenous list of positions, proper motions, photometry in a blue and red band and estimates of the magnitudes in the Gaia G and G_RVS bands: Tycho2, UCAC4, Hipparcos, PPMXL, GSC2.3 and Sky2000. Originally ASC sources were selected from the Initial Gaia Source List (IGSL, <A HREF="http://cdsarc.u-strasbg.fr/cgi-bin/Cat?I/324">I/324</A>). However, here we produce a cleaner catalog starting from the bright source catalogs and using the following criteria: 1) The candidate must be in the Tycho2, UCAC4, Hipparcos or Sky2000 catalog. 2) The Gaia G magnitude must be brighter than 13.4. 3) The star must be isolated from other objects of similar magnitudes 4) The object must not be in the Washington Double Star catalog 5) If a healpix 6th region has more than 1000 objects the magnitude limit is reduced to reduce the number of objects in that region. Since the ASC was produced independently from the IGSL using different procedures there is not a direct 1 to 1 match between ASC and IGSL entries. We have matched the ASC to the IGSL and found that 9 out of the 8 million entries do not have a clear match. Since there may still remain ambiguous matches in the 8 million matched objects, we decided to assign the sourceIDs of the IGSL with the adjustment that the runningnumber is equal to the IGSL runningnumber + 320000. Included Catalogs: Tycho2, UCAC4, Sky2000, HIPPARCOS for candidates and the PPMXL, GSC2.3 were used to calculating magnitudes.
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Search Results
1222. AS CrB BVRI light curves
- ID:
- ivo://CDS.VizieR/J/other/NewA/51.1
- Title:
- AS CrB BVRI light curves
- Short Name:
- J/other/NewA/51.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The first high-precision BVRI light curves of the eclipsing binary AS CrB were presented and were analyzed by the 2015 version of the W-D code. It is found that AS CrB is an extreme mass-ratio, deep contact binary with a fill-out factor of f=59.6+/-2.5% and a mass ratio of q=0.172+/-0.008q=0.172+/-0.008. Based on the photometric solution and the Dartmouth isochrones model, the masses, radii, and luminosities of the components are estimated as follows: M_1_=1.25+/-0.15M_{sun}_, M_1_=1.25+/-0.15M_{sun}_, M_2_=0.21+/-0.06M_{sun}_, M_2_=0.21+/-0.06M_{sun}_, R_1_=1.40+/-0.07R_{sun}_, R_1_=1.40+/-0.07R_{sun}_, R_2_=0.67+/-0.04R_{sun}_, R_2_=0.67+/-0.04R_{sun}_, L_1_=3.2+/-0.2L_{sun}_, L_1_=3.2+/-0.2L_{sun}_, and L_2_=0.72+/-0.04L_{sun}_, L_2_=0.72+/-0.04L_{sun}_, with an estimated distance 459+/-42pc. These uncertainties mainly come from the errors of the color used to estimate the temperature of the primary star. By investigating all of the available times of light minima, it is found that the Observed-Calculated [(O-C)(O-C)] curve shows a long-term period increase, with a rate of dP/dt=+(3.46+/-0.01)x10^-7^dP/dt=+(3.46+/-0.01)x10^-7^day/year. As an extreme mass-ratio contact binary, AS CrB may merge into a single star, such as an FK Com-type star or a blue straggler, because of the orbital instability.
- ID:
- ivo://CDS.VizieR/J/A+A/622/A156
- Title:
- A search for accreting young companions
- Short Name:
- J/A+A/622/A156
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In recent years, our understanding of giant planet formation progressed substantially. There have even been detections of a few young protoplanet candidates still embedded in the circumstellar disks of their host stars. The exact physics that describes the accretion of material from the circumstellar disk onto the suspected circumplanetary disk and eventually onto the young, forming planet is still an open question. We seek to detect and quantify observables related to accretion processes occurring locally in circumstellar disks, which could be attributed to young forming planets. We focus on objects known to host protoplanet candidates and/or disk structures thought to be the result of interactions with planets. We analyzed observations of six young stars and their surrounding environments with the SPHERE/ZIMPOL instrument on the Very Large Telescope (VLT) in the H{alpha} filter (656nm) and a nearby continuum filter (644.9nm). We redetect the known accreting M-star companion HD142527 B with the highest published signal to noise to date in both H{alpha} and the continuum. No other companions are detected. We analyzed observations of six young stars (age 3.5-10Myr) and their surrounding environments with the SPHERE/ZIMPOL instrument on the Very Large Telescope (VLT) in the H{alpha}filter (656nm) and a nearby continuum filter (644.9nm). We applied several point spread function (PSF) subtraction techniques to reach the highest possible contrast near the primary star, specifically investigating regions where forming companions were claimed or have been suggested based on observed disk morphology.
- ID:
- ivo://CDS.VizieR/J/A+A/391/159
- Title:
- A search for Compact High-Velocity Clouds
- Short Name:
- J/A+A/391/159
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An automated search is applied to the Leiden/Dwingeloo HI Survey (LDS) for high-velocity clouds north of Dec.=-28{deg}. From the general catalog we extract a sample of relatively small (less than about 8{deg}) and isolated high-velocity clouds, CHVCs: anomalous-velocity HI clouds which are sharply bounded in angular extent with no kinematic or spatial connection to other HI features down to a limiting column density of 1.5x10^18cm^-2. Unambiguously isolated objects are given the "CHVC" designation, while those with some degree of ambiguity in this classification or designated "CHVC:" or "CHVC?". The vast majority of features show diffuse connections at low column densities with the extended HVC complexes and are simply designated as "HVC" features. The automated search algorithm has been applied to the HIPASS and to the Leiden/Dwingeloo data sets. The results from the LDS are described here; Putman et al. (2002, Cat. <J/AJ/123/873>) describe application of this algorithm to the HIPASS material. Only those catalog entries which have and additional ID listed have been confirmed in independent data.
- ID:
- ivo://CDS.VizieR/J/ApJ/777/64
- Title:
- A search for double-peaked AGNs in AGES
- Short Name:
- J/ApJ/777/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dual supermassive black holes (SMBHs) with kiloparsec-scale separations in merger-remnant galaxies are informative tracers of galaxy evolution, but the avenue for identifying them in large numbers for such studies is not yet clear. One promising approach is to target spectroscopic signatures of systems where both SMBHs are fueled as dual active galactic nuclei (AGNs), or where one SMBH is fueled as an offset AGN. Dual AGNs may produce double-peaked narrow AGN emission lines, while offset AGNs may produce single-peaked narrow AGN emission lines with line-of-sight velocity offsets relative to the host galaxy. We search for such dual and offset systems among 173 Type 2 AGNs at z<0.37 in the AGN and Galaxy Evolution Survey (AGES), and we find two double-peaked AGNs and five offset AGN candidates. When we compare these results to a similar search of the DEEP2 Galaxy Redshift Survey and match the two samples in color, absolute magnitude, and minimum velocity offset, we find that the fraction of AGNs that are dual SMBH candidates increases from z=0.25 to z=0.7 by a factor of ~6 (from 2/70 to 16/91, or 2.9_-1.9_^+3.6^% to 18_-5_^+5^%). This may be associated with the rise in the galaxy merger fraction over the same cosmic time. As further evidence for a link with galaxy mergers, the AGES offset and dual AGN candidates are tentatively ~3 times more likely than the overall AGN population to reside in a host galaxy that has a companion galaxy (from 16/173 to 2/7, or 9_-2_^+3^% to 29_-19_^+26^%). Follow-up observations of the seven offset and dual AGN candidates in AGES will definitively distinguish velocity offsets produced by dual SMBHs from those produced by narrow-line region kinematics, and will help sharpen our observational approach to detecting dual SMBHs.
- ID:
- ivo://CDS.VizieR/II/239
- Title:
- A search for faint blue stars.
- Short Name:
- II/239
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Continuing the survey for faint blue stars at high galactic latitudes of Haro and Luyten (1962, Cat. <III/74>, this search was made, following the Tonantzintla three image method, with the 48" Schmidt telescope of Mt. Palomar. In the first paper, a catalogue of 4431 stars and 84 compact objects found in nine PSS fields scattered around the NGP is presented, with the 1950 positions and the estimated magnitudes and colour classes. The catalogue contains also extensive identifications with previous surveys, including some known QSSs; 16 QSS candidates are proposed; spectra are available for most of the unknown stars brighter than 14mag. In the second paper, a catalogue of 2011 stars and compact objects is presented with the 1950 positions and the estimated magnitude and colour classes. Complementary to the catalogue of Haro and Luyten (1962BITon...3...37H) at declination +6{deg} and 0{deg} it contains also extensive identifications with previous surveys and known QSO's; candidate QSO's are indicated; spectra are available for some new blue stars. The third and last part of the survey of faint blue objects contains a catalogue of 2484 starlike or compact objects is presented with the 1950 positions, estimated magnitudes, color classes and extensive identifications with stars of previous surveys and known QSO's. The three parts were merged into a single file "catalog.dat".
- ID:
- ivo://CDS.VizieR/J/ApJ/105/85
- Title:
- A search for faint blue stars
- Short Name:
- J/ApJ/105/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Four-color photography has been used in a search for faint blue stars with the 18-inch Schmidt telescope at Palomar, undertaken in the hope of finding new white dwarfs. The results are given for stars brighter than magnitude 15.0pg in 2 regions: the Hyades cluster and the North Galactic Pole. Spectroscopic observations were made with the 100-inch reflector. In the "hz.dat" file, corresponding to the table 4 of the paper, the stars were identified and accurate positions added by B. Skiff (Lowell Observatory) in January 2005, using the finding charts published in the "First Conference on Faint Blue Stars" held in Strasbourg in Aug. 1964, p.121 (Univ. Minnesota, 1965)
- ID:
- ivo://CDS.VizieR/J/AJ/158/243
- Title:
- A search for multiplanet systems with TESS
- Short Name:
- J/AJ/158/243
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Transiting exoplanets in multiplanet systems exhibit non-Keplerian orbits as a result of the gravitational influence from companions, which can cause the times and durations of transits to vary. The amplitude and periodicity of the transit time variations are characteristic of the perturbing planet's mass and orbit. The objects of interest from the Transiting Exoplanet Survey Satellite (TESS) are analyzed in a uniform way to search for transit timing variations (TTVs) with sectors 1-3 of data. Due to the volume of targets in the TESS candidate list, artificial intelligence is used to expedite the search for planets by vetting nontransit signals prior to characterizing the light-curve time series. The residuals of fitting a linear orbit ephemeris are used to search for TTVs. The significance of a perturbing planet is assessed by comparing the Bayesian evidence between a linear and nonlinear ephemeris, which is based on an N-body simulation. Nested sampling is used to derive posterior distributions for the N-body ephemeris and in order to expedite convergence, custom priors are designed using machine learning. A dual-input, multi-output convolutional neural network is designed to predict the parameters of a perturbing body given the known parameters and measured perturbation (O-C). There is evidence for three new multiplanet candidates (WASP-18, WASP-126, TOI 193) with nontransiting companions using the two-minute cadence observations from TESS. This approach can be used to identify stars in need of longer radial velocity and photometric follow-up than those already performed.
- ID:
- ivo://CDS.VizieR/J/ApJ/745/24
- Title:
- A search for new companions with CHARA
- Short Name:
- J/ApJ/745/24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a comprehensive search for new companions to nearby solar-type stars using the separated fringe packet (SFP) technique at the Center for High Angular Resolution Astronomy (CHARA) Array. Our search included 636 observations of 186 stars, searching for companions with separations of approximately 8-80 mas and moderate brightness ratios ({Delta}K<~1.5). This survey was undertaken to support a comprehensive assessment of companions to solar-type stars within 25 pc. We detected separated fringe companions to two stars (HD 3196 and 79096) and found faint companion signatures to two more stars (HD 98231 and 137763). All of these companions are previously known by spectroscopic methods, and three of them have speckle interferometric observations as well. The faint companion seen to HD 98231 represents the first visual detection of this spectroscopic companion. Our null detection for new companions implies that the presumed gap between spectroscopic and visual techniques has largely been filled for nearby solar-type stars, thanks to systematic radial-velocity observations over multiple decades and a thorough coverage using visual techniques, especially speckle interferometric observations. We also generate simulated fringe packets to derive detection limits for SFP binaries using the CHARA Array.
- ID:
- ivo://CDS.VizieR/J/A+A/473/177
- Title:
- A search for pre-biotic molecules
- Short Name:
- J/A+A/473/177
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Low-noise, 0.8MHz resolution spectra around 90GHz towards four hot core sources: Orion KL, W51 e1/e2, S140, and W3(OH), are presented. The observations were performed using the 3mm SIS receiver at the Onsala 20m telescope. The observations were made in the beam-switching mode, the spectrum intensity is given in T_A_^*^ and high-order polynomial baselines have been subtracted. At 90GHz the Onsala 20m telescope has a beam FWHM of ~42arcsec and a main-beam efficiency of ~0.6. Due to changes in frequency setting during the observing period the frequency ranges are not identical for each source, but in all cases the ranges include the transitions used to determine the upper column densities of amino acetonitrile (H_2_NCH_2_CN), vinyl acetylene (C_2_H_3_CCH), oxiranecarbonitrile (c-C_3_H_3_NO), and amino-ethanol (NH_2_CH_2_CH_2_OH), presented in the paper. Note that the absorptions, seen in the S140 and the W3(OH) spectra around the strong HCN-line at 90.663GHz, are artificial.
