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- ID:
- ivo://CDS.VizieR/J/A+A/544/A9
- Title:
- The International Deep Planet Survey. I.
- Short Name:
- J/A+A/544/A9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Breakthrough direct detections of planetary companions orbiting A-type stars confirm the existence of massive planets at relatively large separations, but dedicated surveys are required to estimate the frequency of similar planetary systems. To measure the first estimation of the giant exoplanetary systems frequency at large orbital separation around A-stars, we have conducted a deep-imaging survey of young (8-400Myr), nearby (19-84pc) A- and F-stars to search for substellar companions in the ~10-300AU range. The sample of 42 stars combines all A-stars observed in previous AO planet search surveys reported in the literature with new AO observations from VLT/NaCo and Gemini/NIRI. It represents an initial subset of the International Deep Planet Survey (IDPS) sample of stars covering M- to B-stars. The data were obtained with diffraction-limited observations in H- and Ks-band combined with angular differential imaging to suppress the speckle noise of the central stars, resulting in typical 5-sigma detection limits in magnitude difference of 12mag at 1", 14mag at 2" and 16mag at 5" which is sufficient to detect massive planets. A detailed statistical analysis of the survey results is performed using Monte Carlo simulations. Considering the planet detections, we estimate the fraction of A-stars having at least one massive planet (3-14M_Jup_) in the range 5-320AU to be inside 5.9-18.8% at 68% confidence, assuming a flat distribution for the mass of the planets. By comparison, the brown dwarf (15-75M_Jup_) frequency for the sample is 2.0-8.9% at 68% confidence in the range 5-320AU. Assuming power law distributions for the mass and semimajor axis of the planet population, the AO data are consistent with a declining number of massive planets with increasing orbital radius which is distinct from the rising slope inferred from radial velocity (RV) surveys around evolved A-stars and suggests that the peak of the massive planet population around A-stars may occur at separations between the ranges probed by existing RV and AO observations. Finally, we report the discovery of three new close M-star companions to HIP 104365 and HIP 42334.
- ID:
- ivo://CDS.VizieR/J/MNRAS/468/196
- Title:
- The invisible AGN catalogue
- Short Name:
- J/MNRAS/468/196
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A large fraction of active galactic nuclei (AGN) are 'invisible' in extant optical surveys due to either distance or dust-obscuration. The existence of this large population of dust-obscured, infrared (IR)-bright AGN is predicted by models of galaxy-supermassive black hole coevolution and is required to explain the observed X-ray and IR backgrounds. Recently, IR colour cuts with Wide-field Infrared Survey Explorer have identified a portion of this missing population. However, as the host galaxy brightness relative to that of the AGN increases, it becomes increasingly difficult to differentiate between IR emission originating from the AGN and from its host galaxy. As a solution, we have developed a new method to select obscured AGN using their 20-cm continuum emission to identify the objects as AGN. We created the resulting invisible AGN catalogue by selecting objects that are detected in AllWISE (mid-IR) and FIRST (20 cm), but are not detected in SDSS (optical) or 2MASS (near-IR), producing a final catalogue of 46 258 objects. 30 per cent of the objects are selected by existing selection methods, while the remaining 70 per cent represent a potential previously unidentified population of candidate AGN that are missed by mid-IR colour cuts. Additionally, by relying on a radio continuum detection, this technique is efficient at detecting radio-loud AGN at z>=0.29, regardless of their level of dust obscuration or their host galaxy's relative brightness.
- ID:
- ivo://CDS.VizieR/J/A+A/341/98
- Title:
- The ionizing cluster of 30 Doradus. I.
- Short Name:
- J/A+A/341/98
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- UBV profile fitting photometry is presented for 1469 stars within 90arcsec of the center of the ionizing cluster of 30 Doradus (NGC 2070). A value of 0.82+/-0.03 is found for the extinction parameter S=E(U-B)/E(B-V), constant over almost the whole area covered by this research, with some evidence for local variations. Two reddening components can be identified: a smooth and moderate one that increases towards R136, and a clumpy one varying widely across the face of the cluster. The total-to-selective extinction parameter, R_V_= A_V_/E(B-V), is found to be in the range of 3.0 to 3.7, consistent with previous determinations. A new visualization tool, the colour-magnitude stereogram, is introduced and used to argue that: (1) the observations imply mass segregation in a dust filled cluster; (2) that there has been continuous dust formation near the cluster core up to the present; and (3) that an insidious systematic error has plagued previous determinations of IMF slopes. A method to obtain an unbiased estimate of the slope is discussed.
- ID:
- ivo://CDS.VizieR/J/A+A/587/A121
- Title:
- The IR source catalog of nearby galaxies
- Short Name:
- J/A+A/587/A121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To complement the study of transient phenomena and to assist subsequent observations in the mid-infrared, we extract point source photometry from archival mosaics of nearby galaxies with high star formation rates within 4 Mpc. Point spread function photometry was performed on sources detected in both Spitzer IRAC 3.6um and 4.5um bands at greater than 3{sigma} above background. These data were then supplemented by aperture photometry in the IRAC 5.8um and 8.0um bands conducted at the positions of the shorter wavelength sources. For sources with no detected object in the longer wavelengths, we estimated magnitude limits based on the local sky background.
- ID:
- ivo://CDS.VizieR/J/A+A/400/903
- Title:
- The ISOGAL field FC-01863+00035
- Short Name:
- J/A+A/400/903
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A 0.35x0.29{deg} field centered at l=-18.63{deg}, b=0.35{deg} was observed during the ISOGAL survey by ISOCAM imaging at 7{mu}m and 15{mu}m. 648 objects were detected and their brightness are measured. By combining with the DENIS data in the near-infrared J and Ks bands, one derives the extinction at 7{mu}m through A_Ks_-A_7_=0.35(A_J_-A_Ks_) which yields A_7_/Av~0.03 from the near-IR extinction values of van de Hulst-Glass (Glass, 1999MNRAS.308..127G). The extinction structure along the line of sight is then determined from the values of J-Ks or Ks-[7] of the ISOGAL sources identified as RGB or early AGB stars with mild mass-loss. The distribution of Av ranges from 0 to ~45 and it reflects the concentration of the extinction in the spiral arms. Based on their locations in color-magnitude diagrams and a few cross-identifications with IRAS and MSX sources, the nature of objects is discussed in comparison with the case of a low extinction field in Baade's Window. Most of the objects are either AGB stars with moderate mass loss rate or luminous RGB stars. Some of them may be AGB stars with high mass loss rate. In addition, a few young stellar objects (YSOs) are present.
- ID:
- ivo://CDS.VizieR/II/243
- Title:
- The ISOGAL Point Source Catalogue - IGPSC
- Short Name:
- II/243
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ISOGAL survey is one of the largest imaging programme performed by the ISO satellite. About 16deg^2^ mainly distributed in the inner Galactic disk were mapped at 7 and/or 15 micron ({mu}m). Because of highly structured background and high source density, a special point source extraction algorithm was used and resulted in a 100000 point source catalogue. The mid-infrared data have been associated with near-infrared DENIS sources, providing an up to five wavelength photometric catalogue with a typical astrometric accuracy better than 1 arcsecond. The point source catalogue contains the positional and photometric parameters of all ISOGAL sources, together with various quality flags aimed at giving an estimate of the reliability of the detections and of the associations between the different bands (see the paper for a complete description).
- ID:
- ivo://CDS.VizieR/J/A+A/373/730
- Title:
- The IUE Absolute Flux Scale
- Short Name:
- J/A+A/373/730
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Tables tablea1 to tablea6 show the absolute fluxes of the IUE standard stars used for the derivation of the cameras Inverse Sensitivity Curves for the IUE Final Archive. The relative fluxes of the standard stars have been derived with the WD model, and the zero point of the scale has been set by OAO-2 observations. These fluxes define the absolute flux scale of IUE. Table tableb1 contains the model fluxes of the White Dwarf G191 B2B scaled to the OAO-2 flux scale.
6739. The Kepler-INT survey
- ID:
- ivo://CDS.VizieR/J/AJ/144/24
- Title:
- The Kepler-INT survey
- Short Name:
- J/AJ/144/24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper describes the first data release of the Kepler-INT Survey (KIS) that covers a 116deg^2^ region of the Cygnus and Lyra constellations. The Kepler field is the target of the most intensive search for transiting planets to date. Despite the fact that the Kepler mission provides superior time-series photometry, with an enormous impact on all areas of stellar variability, its field lacks optical photometry complete to the confusion limit of the Kepler instrument necessary for selecting various classes of targets. For this reason, we follow the observing strategy and data reduction method used in the IPHAS and UVEX galactic plane surveys in order to produce a deep optical survey of the Kepler field. This initial release concerns data taken between 2011 May and August, using the Isaac Newton Telescope on the island of La Palma. Four broadband filters were used, U, g, r, i, as well as one narrowband one, H{alpha}, reaching down to a 10{sigma} limit of ~20th mag in the Vega system. Observations covering ~5 deg^2^, thus about half of the field, passed our quality control thresholds and constitute this first data release. We derive a global photometric calibration by placing the KIS magnitudes as close as possible to the Kepler Input Catalog (KIC) photometry. The initial data release catalog containing around 6 million sources from all the good photometric fields is available for download from the KIS Web site (www.astro.warwick.ac.uk/research/kis/) as well as via MAST (KIS magnitudes can be retrieved using the MAST enhanced target search page http://archive.stsci.edu/kepler/kepler_fov/search.php and also via Casjobs at MAST Web site http://mastweb.stsci.edu/kplrcasjobs/).
6740. The large TNO 2002 TC302
- ID:
- ivo://CDS.VizieR/J/A+A/639/A134
- Title:
- The large TNO 2002 TC302
- Short Name:
- J/A+A/639/A134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- On 28th January 2018, the large Trans-Neptunian Object 2002 TC_302_ occulted a m_v_~15.3 star with designation 593-005847 in the UCAC4 stellar catalog, corresponding to Gaia source 130957813463146112. Twelve positive occultation chords were obtained from Italy, France, Slovenia and Switzerland. Also, four negative detections were obtained near the north and south limbs. This represents the best observed stellar occultation by a TNO other than Pluto in terms of the number of chords published thus far. From the twelve chords, an accurate elliptical fit to the instantaneous projection of the body can be obtained, compatible with the near misses. The resulting ellipse has major and minor axes of 543+/-18km and 460+/-11km, respectively, with a position angle of 3+/-1 degrees for the minor axis. This information, combined with rotational light curves obtained with the 1.5-m telescope at Sierra Nevada Observatory and the 1.23-m telescope at Calar Alto observatory, allows us to derive possible three-dimensional shapes and density estimations for the body based on hydrostatic equilibrium assumptions. The effective diameter in equivalent area is around 84km smaller than the radiometrically derived diameter using thermal data from Herschel and Spitzer Space Telescopes. This might indicate the existence of an unresolved satellite of up to ~300km in diameter, to account for all the thermal flux, although the occultation and thermal diameters are compatible within their error bars given the considerable uncertainty of the thermal results. The existence of a potential satellite also appears to be consistent with other ground-based data presented here. From the effective occultation diameter combined with absolute magnitude measurements we derive a geometric albedo of 0.147+/-0.005, which would be somewhat smaller if 2002 TC_302_ has a satellite. The best occultation light curves do not show any signs of ring features or any signatures of a global atmosphere.
