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21782. 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.
- ID:
- ivo://CDS.VizieR/J/AJ/156/286
- Title:
- The LEECH exoplanet imaging survey
- Short Name:
- J/AJ/156/286
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the largest L' (3.8 {mu}m) direct imaging survey for exoplanets to date, the Large Binocular Telescope Interferometer Exozodi Exoplanet Common Hunt (LEECH). We observed 98 stars with spectral types from B to M. Cool planets emit a larger share of their flux in L' compared to shorter wavelengths, affording LEECH an advantage in detecting low-mass, old, and cold-start giant planets. We emphasize proximity over youth in our target selection, probing physical separations smaller than other direct imaging surveys. For FGK stars, LEECH outperforms many previous studies, placing tighter constraints on the hot-start planet occurrence frequency interior to ~20 au. For less luminous, cold-start planets, LEECH provides the best constraints on giant-planet frequency interior to ~20 au around FGK stars. Direct imaging survey results depend sensitively on both the choice of evolutionary model (e.g., hot- or cold-start) and assumptions (explicit or implicit) about the shape of the underlying planet distribution, in particular its radial extent. Artificially low limits on the planet occurrence frequency can be derived when the shape of the planet distribution is assumed to extend to very large separations, well beyond typical protoplanetary dust-disk radii (~<50 au), and when hot-start models are used exclusively. We place a conservative upper limit on the planet occurrence frequency using cold-start models and planetary population distributions that do not extend beyond typical protoplanetary dust-disk radii. We find that ~<90% of FGK systems can host a 7-10 M_Jup_ planet from 5 to 50 au. This limit leaves open the possibility that planets in this range are common.
- ID:
- ivo://org.gavo.dc/lspm/q/main
- Title:
- The Lepine-Shara Catalog of High Proper Motion Stars
- Short Name:
- lspm.main
- Date:
- 15 Aug 2024 15:17:04
- Publisher:
- The GAVO DC team
- Description:
- The LSPM catalog is a comprehensive list of 61,977 stars north of the J2000 celestial equator that have proper motions larger than 0.15"/yr (local-background-stars frame). Positions are given with an accuracy of <~100 mas at the 2000.0 epoch, and absolute proper motions are given with an accuracy of ~8 mas/yr. The catalog is estimated to be over 99% complete at high Galactic latitudes (|b|>15{deg}) and over 90% complete at low Galactic latitudes (|b|>15{deg}), down to a magnitude.
21785. The LF Survey
- ID:
- ivo://CDS.VizieR/II/221A
- Title:
- The LF Survey
- Short Name:
- II/221A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The LF program was initiated at the Warner and Swasey Observatory by S.W. McCuskey for studies of the variations of the stellar luminosity function (LF) in the Milky Way. The program originally presented in a paper of July 1947 (1947ApJ...106....1M), proposes an observation of selected Milky Way regions with the 24-36-inch Schmidt telescope of the Warner and Swasey Observatory down to mpg=12.25; the observations result in spectral classification, photographic and photored magnitudes of a large number of stars. The original catalogues contain annotated charts of the studied regions, and tables with the spectral types and magnitudes. The catalog included here is a compilation of 13 publications of this program corresponding to the fields LF1 to LF9 (detailed references in the "References" section below). It was prepared by Brian Skiff (Lowell Observatory) over the period 1994-2003, and includes the original data (with the exception of the "red index" colors too noisy to be of use), with cross-identifications to modern catalogues like the GSC (I/254) that give accurate J2000 positions; he also added extensive notes.
- ID:
- ivo://CDS.VizieR/J/ApJS/185/156
- Title:
- The Lick AGN monitoring project
- Short Name:
- J/ApJS/185/156
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Lick AGN Monitoring Project targeted 13 nearby Seyfert 1 galaxies with the intent of measuring the masses of their central black holes using reverberation mapping. The sample includes 12 galaxies selected to have black holes with masses roughly in the range 10^6^-10^7^M_{sun}_, as well as the well-studied active galactic nucleus (AGN) NGC 5548. In conjunction with a spectroscopic monitoring campaign, we obtained broadband B and V images on most nights from 2008 February through 2008 May. The imaging observations were carried out by four telescopes: the 0.76m Katzman Automatic Imaging Telescope, the 2m Multicolor Active Galactic Nuclei Monitoring telescope, the Palomar 60 inch (1.5m) telescope, and the 0.80m Tenagra II telescope. Having well-sampled light curves over the course of a few months is useful for obtaining the broad-line reverberation lag and black hole mass, and also allows us to examine the characteristics of the continuum variability. In this paper, we discuss the observational methods and the photometric measurements, and present the AGN continuum light curves. We measure various variability characteristics of each of the light curves. We do not detect any evidence for a time lag between the B- and V-band variations, and we do not find significant color variations for the AGNs in our sample.
21787. The LickX Spectra library
- ID:
- ivo://CDS.VizieR/J/A+A/561/A36
- Title:
- The LickX Spectra library
- Short Name:
- J/A+A/561/A36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Collections of stellar spectra, often called stellar libraries, are useful in a variety of applications in the field of stellar populations. This is an attempt to improve the much-used Lick library of stellar spectra by removing jitter from the wavelength scale via cross-correlation, and calling the result the LickX library.
- ID:
- ivo://org.gavo.dc/life/q/tables
- Title:
- The LIFE Target Star Database LIFETD
- Date:
- 07 Jun 2024 09:53:28
- Publisher:
- The GAVO DC team
- Description:
- The LIFE Target Star Database contains information useful for the planned `LIFE mission`_ (mid-ir, nulling interferometer in space). It characterizes possible target systems including information about stellar, planetary and disk properties. The data itself is mainly a collection from different other catalogs. Note that LIFE's target database is living data. The content – and to some extent even structure – of these tables may change at any time without prior warning. .. _LIFE mission: https://life-space-mission.com/
- ID:
- ivo://CDS.VizieR/J/ApJ/504/27
- Title:
- The L_X_-T Relation for Nearby Clusters
- Short Name:
- J/ApJ/504/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The X-ray luminosity-temperature relation for nearby T ~= 3.5-10 keV clusters is rederived using new ASCA temperatures and ROSAT luminosities. Both quantities are derived by directly excluding the cooling flow regions. This correction results in a greatly reduced scatter in the L_X_-T relation; cooling flow clusters are similar to others outside the small cooling flow regions. For a fit of the form L_bol_ {prop.to} T^{alpha}^, we obtain {alpha} = 2.64 +/- 0.27 (90%) and a residual rms scatter in log L_bol_ of 0.10. The derived relation can be directly compared to theoretical predictions that do not include radiative cooling. It also provides an accurate reference point for future evolution searches and comparison to cooler clusters. The new temperatures and L_X_-T relation together with a newly selected cluster sample are used to update the temperature function at z ~ 0.05. The resulting function is generally higher and flatter than, although within the errors of, the previous estimates by Edge and coworkers and Henry and Arnaud (as rederived by Eke and coworkers). For a qualitative estimate of constraints that the new data place on the density fluctuation spectrum, we apply the Press-Schechter formalism for {Omega}_0_ = 1 and 0.3. For {Omega}_0_ = 1, assuming cluster isothermality, the temperature function implies {sigma}_8_ = 0.55 +/- 0.03, while taking into account the observed cluster temperature profiles, {sigma}_8_ = 0.51 +/- 0.03, consistent with the previously derived range. The dependence of {sigma}_8_ on {Omega}_0_ is different from the earlier results because of our treatment of the slope of the fluctuation spectrum, n, as a free parameter. For the considered values of {Omega}_0_, n = -(2.0-2.3) +/- 0.3, somewhat steeper than that derived from the earlier temperature function data, in agreement with the local slope of the galaxy fluctuation spectrum from the Automatic Plate Measuring Facility (APM) survey, and significantly steeper than the standard cold dark matter prediction.
- ID:
- ivo://CDS.VizieR/J/A+A/551/A78
- Title:
- The Magellanic Bridge Catalogue of Stars - MBCS
- Short Name:
- J/A+A/551/A78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Magellanic system comprises the Large Magellanic Cloud (LMC), the Small Magellanic Cloud (SMC), and the less frequently observed Magellanic Bridge and Magellanic Stream. The Bridge is traced by neutral gas and has an observed stellar component, while the Stream consists of gas only, with no observed stellar counterpart to date. This study uses catalogues created in the direction of the Bridge from 2MASS and WISE to investigate the stellar content of the Magellanic Bridge.