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- ID:
- ivo://CDS.VizieR/J/ApJS/188/384
- Title:
- The VLA-COSMOS survey. IV.
- Short Name:
- J/ApJS/188/384
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the context of the VLA-COSMOS Deep project, additional VLA A array observations at 1.4GHz were obtained for the central degree of the COSMOS field and combined with the existing data from the VLA-COSMOS Large project. A newly constructed Deep mosaic with a resolution of 2.5" was used to search for sources down to 4{sigma} with 1{sigma}~12uJy/beam in the central 50'x50'. This new catalog is combined with the catalog from the Large project (obtained at 1.5"x1.4" resolution) to construct a new Joint catalog. All sources listed in the new Joint catalog have peak flux densities of >=5{sigma} at 1.5" and/or 2.5" resolution to account for the fact that a significant fraction of sources at these low flux levels are expected to be slightly resolved at 1.5" resolution. All properties listed in the Joint catalog, such as peak flux density, integrated flux density, and source size, are determined in the 2.5" resolution Deep image. In addition, the Joint catalog contains 43 newly identified multi-component sources.
- ID:
- ivo://CDS.VizieR/VIII/79A
- Title:
- The VLA Low-frequency Sky Survey at 74MHz
- Short Name:
- VIII/79A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The VLA Low-Frequency Sky Survey (VLSS) is a 74MHz (4m) continuum survey covering the entire sky north of -30{deg} declination. Using the VLA in B- and BnA-configurations, we will map the entire survey region at a resolution of 80" and with an average rms noise of 0.1 Jy/beam. For a detailed description of the survey and its scientific motivations, please see the original proposal to the NRAO skeptical review committee. The VLSS is being made as a service to the astronomical community, and the principal data products are being released to the public as soon as they are produced and verified. Details and access to the images can be found at http://lwa.nrl.navy.mil/VLSS/
- ID:
- ivo://CDS.VizieR/J/ApJS/194/25
- Title:
- The VLBA calibrator search for the BeSSeL survey
- Short Name:
- J/ApJS/194/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a survey of radio continuum sources near the Galactic plane using the Very Long Baseline Array (VLBA). Our observations are designed to identify compact extragalactic sources of milliarcsecond size that can be used for parallax measurements in the Bar and Spiral Structure Legacy Survey. We selected point sources from the NVSS and CORNISH catalogs with flux densities above 30mJy and within 1.5{deg} of known maser targets. Of the 1529 sources observed, 199 were detected. For sources detected on three or more baselines, we determined accurate positions and evaluated their quality as potential calibrators. Most of the 1330 sources that were not detected with the VLBA are probably of extragalactic origin.
- ID:
- ivo://CDS.VizieR/J/A+A/558/A24
- Title:
- The VLTI/MIDI survey of Massive YSOs
- Short Name:
- J/A+A/558/A24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Due to inherent difficulties involved in observations and theoretical/numerical simulations of the formation of massive stars, an understanding of the early evolutionary phases of these objects remains elusive. In particular, observationally probing circumstellar material at distances <~100AU from the central star is exceedingly difficult, as such objects are rare (and thus, on average, far away) and typically deeply embedded. Long-baseline mid-infrared interferometry provides one way of obtaining the necessary spatial resolution at appropriate wavelengths to study this class of objects, however, interpreting such observations is often difficult due to sparse spatial-frequency coverage. We aim to characterize the distribution and composition of circumstellar material around young massive stars, and to investigate exactly which physical structures in these objects are probed by long-baseline mid-infrared interferometric observations. We use the two-telescope interferometric instrument MIDI of the Very Large Telescope Interferometer of the European Southern Observatory to observe a sample of 24 intermediate- and high-mass young stellar objects in the N band (8-13 micron). We had successful fringe detections for 20 objects, and present spectrally-resolved correlated fluxes and visibility levels for projected baselines of up to 128m. We fit the visibilities with geometric models to derive the sizes of the emitting regions, as well as the orientation and elongation of the circumstellar material. A subset of 14 objects show the 10 micron silicate feature in absorption in the total and correlated flux spectra. For 13 of these objects, we were able to fit the correlated flux spectra with a simple absorption model, allowing us to constrain the composition and absorptive properties of the circumstellar material.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/21
- Title:
- The VMC survey. XIX. Classical Cepheids in SMC
- Short Name:
- J/ApJS/224/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The "VISTA near-infrared YJK_s_ survey of the Magellanic Clouds System" (VMC) is collecting deep K_s_-band time-series photometry of pulsating variable stars hosted by the two Magellanic Clouds and their connecting Bridge. In this paper, we present Y, J, K_s_ light curves for a sample of 4172 Small Magellanic Cloud (SMC) Classical Cepheids (CCs). These data, complemented with literature V values, allowed us to construct a variety of period-luminosity (PL), period-luminosity-color (PLC), and period-Wesenheit (PW) relationships, which are valid for Fundamental (F), First Overtone (FO), and Second Overtone (SO) pulsators. The relations involving the V, J, K_s_ bands are in agreement with their counterparts in the literature. As for the Y band, to our knowledge, we present the first CC PL, PW, and PLC relations ever derived using this filter. We also present the first near-infrared PL, PW, and PLC relations for SO pulsators to date. We used PW(V, K_s_) to estimate the relative SMC-LMC distance and, in turn, the absolute distance to the SMC. For the former quantity, we find a value of {Delta}{mu}=0.55+/-0.04mag, which is in rather good agreement with other evaluations based on CCs, but significantly larger than the results obtained from older population II distance indicators. This discrepancy might be due to the different geometric distributions of young and old tracers in both Clouds. As for the absolute distance to the SMC, our best estimates are {mu}_SMC_=19.01+/-0.05mag and {mu}_SMC_=19.04+/-0.06mag, based on two distance measurements to the LMC which rely on accurate CC and eclipsing Cepheid binary data, respectively.
- ID:
- ivo://CDS.VizieR/VIII/62
- Title:
- The Westerbork Northern Sky Survey
- Short Name:
- VIII/62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Westerbork Northern Sky Survey (WENSS) is a low-frequency radio survey that covers the whole sky north of 30{deg} at a wavelength of 92cm (330MHz) to a limiting flux density of approximately 18 mJy (5{sigma}). This survey has a resolution of 54"x54" cosec(delta) and a positional accuracy for strong sources of 1.5". The WENSS project is a collaboration between the Netherlands Foundation for Research in Astronomy (NFRA/ASTRON) and the Leiden Observatory.
- ID:
- ivo://CDS.VizieR/J/AJ/161/14
- Title:
- The Wide-field VLBA Calibrator Survey (WFCS)
- Short Name:
- J/AJ/161/14
- Date:
- 09 Mar 2022
- Publisher:
- CDS
- Description:
- This paper presents the results of the largest very long baseline interferometry (VLBI) absolute astrometry campaign to date of 13645 radio source observations with the Very Long Baseline Array. Of these, 7220 have been detected, including 6755 target sources that have never been observed with VLBI before. This makes the present VLBI catalog the largest ever published. The positions of the target sources have been determined with the median uncertainty of 1.7mas, and 15542 images of 7171 sources have been generated. Unlike previous absolute radio astrometry campaigns, observations were made at 4.3 and 7.6GHz simultaneously using a single wide-band receiver. Because of the fine spectral and time resolutions, the field of view was 4'-8'-much greater than the 10"-20" in previous surveys. This made possible the use of input catalogs with low position accuracy and the detection of a compact component in extended sources. Unlike previous absolute astrometry campaigns, both steep- and flat-spectrum sources were observed. The observations were scheduled in the so-called filler mode to fill the gaps between other high-priority programs. This was achieved by the development of the totally automatic scheduling procedure.
1989. The WIRED survey. II.
- ID:
- ivo://CDS.VizieR/J/ApJS/197/38
- Title:
- The WIRED survey. II.
- Short Name:
- J/ApJS/197/38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- With the launch of the Wide-field Infrared Survey Explorer (WISE), a new era of detecting planetary debris and brown dwarfs (BDs) around white dwarfs (WDs) has begun with the WISE InfraRed Excesses around Degenerates (WIRED) Survey. The WIRED Survey is sensitive to substellar objects and dusty debris around WDs out to distances exceeding 100pc, well beyond the completeness level of local WDs. In this paper, we present a cross-correlation of the preliminary Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) WD catalog between the WISE, Two-Micron All Sky Survey (2MASS), UKIRT Infrared Deep Sky Survey (UKIDSS), and SDSS DR7 photometric catalogs. From ~18000 input targets, there are WISE detections comprising 344 "naked" WDs (detection of the WD photosphere only), 1020 candidate WD+M dwarf binaries, 42 candidate WD+BD systems, 52 candidate WD+dust disk systems, and 69 targets with indeterminate infrared excess. We classified all of the detected targets through spectral energy distribution model fitting of the merged optical, near-IR, and WISE photometry. Some of these detections could be the result of contaminating sources within the large (~6") WISE point-spread function; we make a preliminary estimate for the rates of contamination for our WD+BD and WD+disk candidates and provide notes for each target of interest.
- ID:
- ivo://CDS.VizieR/VIII/69A
- Title:
- The WISH catalogue at 352 MHz
- Short Name:
- VIII/69A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Westerbork In the Southern Hemishpere (WISH) is a low-frequency (352MHz) radio survey that covers most of the sky between -25 and -15 degrees (1.60sr) at a wavelength of 92cm to a limiting flux density of approximately 18mJy (5sigma). Due to the very low elevation of the observations, the survey has a much lower resolution in declination than in right ascension (54"x54"cosec{delta}). A correlation with the 1.4GHz NVSS (VIII/65) shows that the positional accuracy is less constrained in declination than in right ascension, but there is no significant systematic error. The correlation with the NVSS was also used to construct a sample of faint Ultra Steep Spectrum sources (file uss.dat, table 2 of the paper). This sample is aimed at increasing the number of known high redshift radio galaxies to allow detailed follow-up studies of these massive galaxies and their environments in the early Universe. WISH is a collaboration between the Netherlands Foundation for Research in Astronomy (NFRA/ASTRON) and the Leiden Observatory. Carlos De Breuck, Yuan Tang, Ger de Bruyn, Huub Rottgering, Wil van Breugel, and Roeland Rengelink. For more information, see the WENSS home page at http://www.strw.leidenuniv.nl/wenss/ or contact wenss.people@strw.leidenuniv.nl
