- 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.
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2972. 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/ApJ/833/176
- Title:
- The magnetic field of L1544. I. NIR data
- Short Name:
- J/ApJ/833/176
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The magnetic field (B-field) of the starless dark cloud L1544 has been studied using near-infrared (NIR) background starlight polarimetry (BSP) and archival data in order to characterize the properties of the plane-of-sky B-field. NIR linear polarization measurements of over 1700 stars were obtained in the H band and 201 of these were also measured in the K band. The NIR BSP properties are correlated with reddening, as traced using the Rayleigh-Jeans color excess (H-M) method, and with thermal dust emission from the L1544 cloud and envelope seen in Herschel maps. The NIR polarization position angles change at the location of the cloud and exhibit their lowest dispersion there, offering strong evidence that NIR polarization traces the plane-of-sky B-field of L1544. In this paper, the uniformity of the plane-of-sky B-field in the envelope region of L1544 is quantitatively assessed. This allows evaluation of the approach of assuming uniform field geometry when measuring relative mass-to-flux ratios in the cloud envelope and core based on averaging of the radio Zeeman observations in the envelope, as done by Crutcher et al. (2009ApJ...692..844C). In L1544, the NIR BSP shows the envelope B-field to be significantly non-uniform and likely not suitable for averaging Zeeman properties without treating intrinsic variations. Deeper analyses of the NIR BSP and related data sets, including estimates of the B-field strength and testing how it varies with position and gas density, are the subjects of later papers in this series.
- ID:
- ivo://CDS.VizieR/VII/233
- Title:
- The 2MASS Extended sources
- Short Name:
- VII/233
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Between 1997 June and 2001 February the Two Micron All Sky Survey (2MASS) collected 25.4 Tbytes of raw imaging data covering 99.998% of the celestial sphere in the near-infrared J(1.25{mu}m), H(1.65{mu}m), and Ks(2.16{mu}m) bandpasses. Observations were conducted from two dedicated 1.3 m diameter telescopes located at Mount Hopkins, Arizona, and Cerro Tololo, Chile. The 2MASS All-Sky Data Release includes the FITS images covering the entire sky, a Point Source Catalog (PSC) of 471 million sources (Cat. II/242), and the present Extended Source Catalog. The 2MASS Extended Source Catalog contains sources that are extended with respect to the instantaneous PSF, such as galaxies and Galactic nebulae. The algorithms used to create the 2MASX catalog are described by Jarett et al. (2000AJ....119.2498J), and in the 2MASS Explanatory Supplement (accessible from the 2MASS Home Page). Briefly, point/ extended-source discrimination was conducted for each band-merged point-source detection by comparing a variety of radial shape, surface brightness, image moments, and symmetry parameters with characteristic stellar parameters using an oblique decision tree classifier. The classification tests included filters to exclude double and triple stars, which were one of the main contaminants in high source density regions. Stellar parameters were measured empirically as a function of time in each scan to compensate for variations in the atmospheric seeing using the aggregate properties of band-merged point-source extractions. The catalog contains 389 columns described briefly in the "Byte-by-byte Description" section below; their description includes also the 2MASS database original column names used in the original descriptions.
- ID:
- ivo://CDS.VizieR/J/ApJS/199/26
- Title:
- The 2MASS Redshift Survey (2MRS)
- Short Name:
- J/ApJS/199/26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the 2MASS Redshift Survey (2MRS), a ten-year project to map the full three-dimensional distribution of galaxies in the nearby universe. The Two Micron All Sky Survey (2MASS) was completed in 2003 and its final data products, including an extended source catalog (XSC), are available online. The 2MASS XSC contains nearly a million galaxies with Ks<=13.5mag and is essentially complete and mostly unaffected by interstellar extinction and stellar confusion down to a galactic latitude of |b|=5{deg} for bright galaxies. Near-infrared wavelengths are sensitive to the old stellar populations that dominate galaxy masses, making 2MASS an excellent starting point to study the distribution of matter in the nearby universe. We selected a sample of 44599 2MASS galaxies with Ks<=11.75mag and |b|>=5{deg} (>=8{deg} toward the Galactic bulge) as the input catalog for our survey. We obtained spectroscopic observations for 11000 galaxies and used previously obtained velocities for the remainder of the sample to generate a redshift catalog that is 97.6% complete to well-defined limits and covers 91% of the sky. This provides an unprecedented census of galaxy (baryonic mass) concentrations within 300Mpc. Earlier versions of our survey have been used in a number of publications that have studied the bulk motion of the Local Group, mapped the density and peculiar velocity fields out to 50h^-1^Mpc, detected galaxy groups, and estimated the values of several cosmological parameters. Additionally, we present morphological types for a nearly complete sub-sample of 20860 galaxies with Ks<=11.25mag and |b|>=10{deg}.
2976. The Mayrit catalogue
- ID:
- ivo://CDS.VizieR/J/A+A/478/667
- Title:
- The Mayrit catalogue
- Short Name:
- J/A+A/478/667
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The young sigma Orionis cluster is an indispensable basis for understanding the formation and evolution of stars, brown dwarfs and planetary-mass objects. Our knowledge of its stellar population is, however, incomplete. I present the Mayrit catalogue, that comprises most of the stars and high-mass brown dwarfs of the cluster. The basis of this work is an optical-near infrared correlation between the 2MASS and DENIS catalogues in a circular area of radius 30 arcmin centred on the OB-type binary sigma Ori AB. The analysis is supported on a bibliographic search of confirmed cluster members with features of youth and on additional X-ray, mid-infrared and astrometric data. I list 241 sigma Orionis stars and brown dwarfs with known features of youth, 97 candidate cluster members (40 are new) and 115 back- and foreground sources in the survey area. The 338 cluster members and member candidates constitute the Mayrit catalogue. This catalogue is a suitable input for studying the spatial distribution, multiplicity, properties and frequency of discs and the complete mass function of sigma Orionis.
- ID:
- ivo://CDS.VizieR/J/ApJS/212/6
- Title:
- The McGill magnetar catalog
- Short Name:
- J/ApJS/212/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of the 26 currently known magnetars and magnetar candidates. We tabulate astrometric and timing data for all catalog sources, as well as their observed radiative properties, particularly the spectral parameters of the quiescent X-ray emission. We show histograms of the spatial and timing properties of the magnetars, comparing them with the known pulsar population, and we investigate and plot possible correlations between their timing, X-ray, and multiwavelength properties. We find the scale height of magnetars to be in the range of 20-31pc, assuming they are exponentially distributed. This range is smaller than that measured for OB stars, providing evidence that magnetars are born from the most massive O stars. From the same fits, we find that the Sun lies ~13-22pc above the Galactic plane, consistent with previous measurements. We confirm previously identified correlations between quiescent X-ray luminosity, L_X_, and magnetic field, B, as well as X-ray spectral power-law indexes, {Gamma} and B, and show evidence for an excluded region in a plot of L_X_ versus {Gamma}. We also present an updated kT versus characteristic age plot, showing that magnetars and high-B radio pulsars are hotter than lower-B neutron stars of similar age. Finally, we observe a striking difference between magnetars detected in the hard X-ray and radio bands; there is a clear correlation between the hard and soft X-ray fluxes, whereas the radio-detected magnetars all have low, soft X-ray flux, suggesting, if anything, that the two bands are anticorrelated.
2978. The Monoceros R2 Cluster
- ID:
- ivo://CDS.VizieR/J/AJ/114/198
- Title:
- The Monoceros R2 Cluster
- Short Name:
- J/AJ/114/198
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an extensive study of the stellar population of an embedded cluster in the MonR2 molecular cloud based upon a wide field (~15'x15') J, H, and K band mosaic, deep near-infrared imaging at J, H, K, and nbL' bands of the central cluster region, and spectroscopic observations of 34 stars. By comparing the properties of the MonR2 cluster with other star forming regions, we ultimately hope to learn how the properties and formation of stars of various masses are related to the local physical conditions. The K band star counts indicate that the MonR2 cluster extends over a ~1.1pcx2.1pc area with a FWHM cluster size of ~0.38pc. Within this region the cluster contains ~309 stars brighter than m_K=14.5m and >~475 stars over all magnitudes with a central stellar volume density of ~9000 stars pc^-3^. We have further explored the properties of the cluster by using the spectroscopic and photometric data to construct an extinction-limited sample of 115 stars in the central 0.77pcx0.77pc region of the cluster that is designed to contain all stars with A_V<=11.3m and stellar masses >=0.1M_{sun}_. As a lower limit, 62% of the stars in this sample contain a near-infrared excess at K and/or L band. The K band excess fraction may be as high as 72% if the accretion characteristics of the stars in the MonR2 cluster are similar to stars in Taurus-Auriga. An initial reconnaissance of the stellar mass function suggests that the ratio of high to low mass stars in the extinction-limited sample is consistent with the value expected for a Miller-Scalo IMF. We do not find compelling evidence for mass segregation in the extinction-limited sample for stellar masses <~2M_{sun}_, although the most massive star (~10M_{sun}_) in the cluster appears to be forming near the cluster center. The properties of the MonR2 cluster are similar to other rich young clusters in the solar neighborhood, such as NGC 2024 and the Trapezium. (c) 1997 American Astronomical Society.
- ID:
- ivo://CDS.VizieR/J/ApJS/193/26
- Title:
- The M33 synoptic stellar survey. I.
- Short Name:
- J/ApJS/193/26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted a ground-based BVI synoptic survey of the Local Group galaxy M33 which covers most of its disk and spans a period of 7 years. The survey targets luminous, long-period variables such as Cepheids and Miras and combines images from the DIRECT project and follow-up observations at the WIYN 3.5m telescope. This paper, the first in a series, presents the discovery and characterization of 564 Cepheid variables, which represent a factor of two increase over previous samples with calibrated point-spread function (PSF) photometry. We also describe the details of the observations and analysis of the survey data, including the use of archival Hubble Space Telescope images to characterize biases in our ground-based PSF photometry.
- ID:
- ivo://CDS.VizieR/J/AJ/153/170
- Title:
- The M33 Synoptic Stellar Survey. II. Mira variables
- Short Name:
- J/AJ/153/170
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the discovery of 1847 Mira candidates in the Local Group galaxy M33 using a novel semi-parametric periodogram technique coupled with a random forest classifier. The algorithms were applied to ~2.4*10^5^ I-band light curves previously obtained by the M33 Synoptic Stellar Survey. We derive preliminary period-luminosity relations at optical, near-infrared, and mid-infrared wavelengths and compare them to the corresponding relations in the Large Magellanic Cloud.
