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- 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.
3763. 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/).
3764. 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.
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJS/235/4
- Title:
- The 105-month Swift-BAT all-sky hard X-ray survey
- Short Name:
- J/ApJS/235/4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of hard X-ray sources detected in the first 105-months of observations with the Burst Alert Telescope (BAT) coded-mask imager on board the Swift observatory. The 105-month Swift-BAT survey is a uniform hard X-ray all-sky survey with a sensitivity of 8.40x10^-12^erg/s/cm^2^ over 90% of the sky and 7.24x10^-12^erg/s/cm^2^ over 50% of the sky in the 14-195keV band. The Swift-BAT 105-month catalog provides 1632 (422 new detections) hard X-ray sources in the 14-195 keV band above the 4.8{sigma} significance level. Adding to the previously known hard X-ray sources, 34% (144/422) of the new detections are identified as Seyfert active galactic nuclei (AGNs) in nearby galaxies (z<0.2). The majority of the remaining identified sources are X-ray binaries (7%, 31) and blazars/BL Lac objects (10%, 43). As part of this new edition of the Swift-BAT catalog, we release eight-channel spectra and monthly sampled light curves for each object in the online journal and at the Swift-BAT 105-month website.
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/697/787
- Title:
- The NAN complex. I. IRAC observations
- Short Name:
- J/ApJ/697/787
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 9deg^2^ map of the North American and Pelican Nebulae regions obtained in all four Infrared Array Camera (IRAC) channels with the Spitzer Space Telescope. The resulting photometry is merged with that at JHKs from Two Micron All Sky Survey and a more spatially limited BVI survey from previous ground-based work. We use a mixture of color-color diagrams to select a minimally contaminated set of more than 1600 objects that we claim are young stellar objects (YSOs) associated with the star-forming region. Because our selection technique uses infrared excess as a requirement, our sample is strongly biased against inclusion of Class III YSOs. The distribution of IRAC spectral slopes for our YSOs indicates that most of these objects are Class II, with a peak toward steeper spectral slopes but a substantial contribution from a tail of Flat spectrum and Class I type objects. By studying the small fraction of the sample that is optically visible, we infer a typical age of a few Myr for the low-mass population. The young stars are clustered, with about a third of them located in eight clusters that are located within or near the LDN 935 dark cloud. Half of the YSOs are located in regions with surface densities higher than 1000YSOs/deg^2^. The Class I objects are more clustered than the Class II stars.
