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2101. The VLTI/MIDI survey of Massive YSOs
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.
2102. The VMC survey. XIX. Classical Cepheids in SMC
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.
2103. The VSOP (the VLBI Space Observatory Programme) 5 GHz AGN (Active Galactic Nuclei) Survey Program Analysis Data
ID:
ivo://jvo/isas/darts/halca/halca_vsop_survey_program_data
Title:
The VSOP (the VLBI Space Observatory Programme) 5 GHz AGN (Active Galactic Nuclei) Survey Program Analysis Data
Short Name:
HALCA_AGN
Date:
19 Oct 2021 06:40:34
Publisher:
JVO
Description:
A significant fraction of the mission time of VSOP was to be dedicated to the VSOP Survey Programme of bright compact Active Galactic Nuclei (AGN) at 5 GHz, which was lead by ISAS. The VSOP Survey Sources are an unbiased dataset of 294 targets, of which 82% were successfully observed.
2104. The Westerbork Northern Sky Survey
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.
2105. The Wide-field VLBA Calibrator Survey (WFCS)
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.
2106. 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.
2107. The WISH catalogue at 352 MHz
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
2108. The XMM-Newton 2nd Incremental Source Catalogue (2XMMi)
ID:
ivo://CDS.VizieR/IX/40
Title:
The XMM-Newton 2nd Incremental Source Catalogue (2XMMi)
Short Name:
IX/40
Date:
21 Oct 2021
Publisher:
CDS
Description:
The 2XMMi catalogue is the fourth publicly released XMM X-ray source catalogue produced by the XMM Survey Science Centre (SSC) consortium, following the 1XMM (Cat. IX/37, released in April 2003), 2XMMp (July 2006) and 2XMM (Cat. IX/39, August 2007) catalogues: 2XMMp was a preliminary version of 2XMM. 2XMMi is an incremental version of the 2XMM catalogue. The 2XMMi catalogue is about 17% larger than the 2XMM catalogue, which it supersedes, due to the 1-year longer baseline of observations included (it is about 8 times larger than the 1XMM catalogue). As such, it is the largest X-ray source catalogue ever produced, containing more than twice as many discrete sources as either the ROSAT survey or pointed catalogues. 2XMMi complements deeper Chandra and XMM-Newton small area surveys, probing a large sky area at the flux limit where the bulk of the objects that contribute to the X-ray background lie. The 2XMMi catalogue provides a rich resource for generating large, well-defined samples for specific studies, utilizing the fact that X-ray selection is a highly efficient (arguably the most efficient) way of selecting certain types of object, notably active galaxies (AGN), clusters of galaxies, interacting compact binaries and active stellar coronae. The large sky area covered by the serendipitous survey, or equivalently the large size of the catalogue, also means that 2XMMi is a superb resource for exploring the variety of the X-ray source population and identifying rare source types. The production of the 2XMMi catalogue has been undertaken by the XMM-Newton SSC consortium in fulfilment of one of its major responsibilities within the XMM-Newton project. The catalogue production process has been designed to exploit fully the capabilities of the XMM-Newton EPIC cameras and to ensure the integrity and quality of the resultant catalogue through rigorous screening of the data. The predecessor 2XMM catalogue was made from a subset of public observations emerging from a re-processing (in 2006/7) of all XMM observations made prior to that point. The creation of the incremental 2XMMi catalogue has been driven by the desire to make public the additional data from that re-processing that were proprietary at the time of the 2XMM release but which subsequently became public before 01 May 2008. These have been augmented with a further 90 observations that have been processed more recently as part of the routine, day-to-day XMM data processing performed by the SSC, which were also public at 01 May 2008. Together, these amount to 626 additional observations (18%) with respect to 2XMM. With these new data, the sky area covered grows by 19% while the number of detections increases by 17% and the number of unique sources by 15%. A key factor in the decision to make the 2XMMi catalogue is the fact that, effectively, all the new data have been processed with the same science analysis software (SAS), pipeline and calibration as used in the aforementioned re-processing. As such, the products from 2XMM and from the new observations form a set of uniformly processed data. With software and calibration changes now being propagated into the SSC processing pipeline, it was deemed timely to make public the largest available uniform catalogue. The catalogue in its FITS version file (2xmmi.fit) has 246897 entries made of 297 columns; a 'slim' version gathering the 39 most relevant columns for the 191870 unique sources detected, is available as an ascii table or a FITS binary table. In both versions, the columns are fully described in the XMM-Newton User Guide available from: http://xmmssc-www.star.le.ac.uk/Catalogue/UserGuide_xmmcat.html The original names of these columns are included in the "Byte-by-byte Description" below (uppercase names within parentheses) Details about the construction of the catalogue can be found from the XMM-Newton Survey Science Centre (http://xmmssc-www.star.le.ac.uk/)
2109. The XMM-Newton 2nd Serendipitous Source Catalogue (2XMM)
ID:
ivo://CDS.VizieR/IX/39
Title:
The XMM-Newton 2nd Serendipitous Source Catalogue (2XMM)
Short Name:
IX/39
Date:
21 Oct 2021
Publisher:
CDS
Description:
2XMM is the second comprehensive catalogue of serendipitous X-ray sources from the European Space Agency's (ESA) XMM-Newton observatory. The catalogue has been constructed by the XMM-Newton Survey Science Centre (SSC) on behalf of ESA. It is the largest X-ray source catalogue ever produced, containing almost twice as many discrete sources as either the ROSAT survey or pointed catalogues. The catalogue contains source detections drawn from 3491 XMM-Newton EPIC observations covering a sky area of about 360 square degrees, made between 2000 February 3 and 2007 March 31; all datasets were publicly available by 2007 May 01 but not all public observations are included in this catalogue. The catalogue contains 246897 X-ray source detections which relate to 191870 unique X-ray sources. The median flux in the total photon energy band (0.2-12keV) of the catalogue detections is about 2.5x10^-14^erg/cm2/s (25aW/m2). About 20% of the sources have total fluxes below 10^-14^erg/cm2/s (10aW/m2). The catalogue in its FITS version file (xmm2cat.fit) has 246897 entries made of 297 columns; a 'slim' version gathering the 39 most relevant columns for the 191870 unique sources detected, is available as an ascii table or a FITS binary table. In both versions, the columns are fully described in the XMM-Newton User Guide available from: http://xmmssc-www.star.le.ac.uk/Catalogue/UserGuide_xmmcat.html The original names of these columns are included in the "Byte-by-byte Description" below (uppercase names within parentheses) Details about the construction of the catalogue can be found from the XMM-Newton Survey Science Centre (http://xmmssc-www.star.le.ac.uk/)
2110. The XMM-Newton survey of the COSMOS field
ID:
ivo://CDS.VizieR/J/ApJ/716/348
Title:
The XMM-Newton survey of the COSMOS field
Short Name:
J/ApJ/716/348
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the final optical identifications of the medium-depth (~60ks), contiguous (2deg^2^) XMM-Newton survey of the COSMOS field. XMM-Newton has detected ~1800 X-ray sources down to limiting fluxes of ~5x10^-16^, ~3x10^-15^, and ~7x10^-15^erg/cm^2^/s in the 0.5-2keV, 2-10keV, and 5-10keV bands, respectively (~1x10^-15^, ~6x10^-15^, and ~1x10^-14^erg/cm^2^/s, in the three bands, respectively, over 50% of the area). The work is complemented by an extensive collection of multiwavelength data from 24um to UV, available from the COSMOS survey, for each of the X-ray sources, including spectroscopic redshifts for >~50% of the sample, and high-quality photometric redshifts for the rest. The XMM and multiwavelength flux limits are well matched: 1760 (98%) of the X-ray sources have optical counterparts, 1711 (~95%) have IRAC counterparts, and 1394 (~78%) have MIPS 24um detections. Spectroscopically identified obscured and unobscured AGNs, as well as normal and star-forming galaxies, present well-defined optical and infrared properties. We devised a robust method to identify a sample of ~150 high-redshift (z>1), obscured AGN candidates for which optical spectroscopy is not available.

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