- 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.
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- ID:
- ivo://CDS.VizieR/J/ApJ/864/11
- Title:
- The VVV Variables (V^4^) catalog
- Short Name:
- J/ApJ/864/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Time-varying phenomena are one of the most substantial sources of astrophysical information, and their study has led to many fundamental discoveries in modern astronomy. We have developed an automated tool to search for and analyze variable sources in the near-infrared Ks band using the data from the VISTA Variables in the Via Lactea (VVV) ESO Public Large Survey. This process relies on the characterization of variable sources using different variability indices calculated from time series generated with point-spread function (PSF) photometry of sources under analysis. In particular, we used two main indices, the total amplitude {Delta}Ks and the eta index {eta}, to identify variable sources. Once the variable objects are identified, periods are determined with generalized Lomb-Scargle periodograms and the information potential metric. Variability classes are assigned according to a compromise between comparisons with VVV templates and the period of the variability. The automated tool is applied on VVV tiles d001 and d002 and led to the discovery of 200 variable sources. We detected 70 irregular variable sources and 130 periodic ones. In addition, nine open-cluster candidates projected in the region are analyzed, and the infrared variable candidates found around these clusters are further scrutinized by cross-matching their locations against emission star candidates from VPHAS+ survey H{alpha} color cuts.
- ID:
- ivo://CDS.VizieR/B/wds
- Title:
- The Washington Visual Double Star Catalog
- Short Name:
- B/wds
- Date:
- 07 Mar 2022 08:05:57
- Publisher:
- CDS
- Description:
- The Washington Visual Double Star Catalog (WDS) is the successor to the Index Catalogue of Visual Double Stars, 1961.0 (IDS; Jeffers and van den Bos, Publ. Lick Obs. 21). Three earlier double star catalogs in XXth century, those by Burnham (BDS, 1906, "General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), Innes (SDS, 1927, "Southern Double Star Catalogue -19 to -90 degrees", Union Observatory, Johannesburg, South Africa), and Aitken (ADS, 1932 "New General Catalogue of Double Stars within 121 degrees of the North Pole", Carnegie Institution of Washington), each covered only a portion of the sky. Both the IDS and the WDS cover the entire sky, and the WDS is intended to contain all known visual double stars for which at least one differential measure has been published. The WDS is continually updated as published data become available. Prior to this, three major updates have been published (Worley and Douglass 1984, "Washington Visual Double Star Catalog, 1984.0", U.S. Naval Observatory, Washington; Worley and Douglass 1997A&AS..125..523W, Cat. I/237; Mason, Wycoff, Hartkopf, Douglass and Worley 2001AJ....122.3466M; and Mason et al. 2006.5). The Washington Double Star Catalog (WDS) has seen numerous changes since the last major release of the catalog. The application of many techniques and considerable industry over the past few years has yielded significant gains in both the number of systems and the number of measures. Is is maintained by the US Naval Observatory, and represents the world's principal database of astrometric double and multiple star information. The WDS contains positions (J2000), discoverer designations, epochs, position angles, separations, magnitudes, spectral types, proper motions, and, when available, Durchmusterung numbers and notes for the components of the systems.
- ID:
- ivo://CDS.VizieR/I/237
- Title:
- The Washington Visual Double Star Catalog, 1996.0
- Short Name:
- I/237
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Washington Visual Double Star Catalog, 1996.0 (WDS) is the successor to the catalog of the same name dated 1984 <I/107>. The WDS is intended to contain all known visual double stars for which at least one differential measure has been published through the end of 1995. It includes a discoverer code, the date of the first and last observations, the number of observations, the position angle and separation for the first and last observation, the magnitudes and spectral types of the components (when available) the proper motion of the system, Durchmusterung numbers of the components and notes for further information.
- ID:
- ivo://CDS.VizieR/J/A+AS/61/451
- Title:
- The 37W catalogue of radio sources in M31
- Short Name:
- J/A+AS/61/451
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The radio continuum emission of the spiral galaxy M31 has been mapped at a wavelength of 21cm with the Westerbork Synthesis Radio Telescope, at an angular resolution of 23"x35", corresponding to a linear resolution of 70x115pc. Five fields have been observed which, when combined, cover the main part of the disk of M31. A catalogue of sources inside the M31 area with a flux density larger than 1mJy (five times the rms noise) is presented.
- 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/IX/12
- Title:
- The WGACAT version of ROSAT sources
- Short Name:
- IX/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- WGACAT is a catalogue of point sources generated at HEASARC from all the ROSAT PSPC (Position Sensitive Proportional Counter) pointing observations from Feb 1991 to March 1994. These were the files available in the public archive at HEASARC as of September 1994. This catalog is an independent research effort aimed at releasing as quickly as possible a list of sources detected by ROSAT in its pointed phase to: (1) identify the detected sources, (2) ensure their timely observation by currently active X-ray missions e.g. ASCA, (3) to search for objects which show exceptional time variability and spectral properties and (4) to provide an independent check of the detection technique used in the official ROSAT project (SAS) processing. WGACAT stands for N.E. White (HEASARC/GSFC). P. Giommi (ESA), and L. Angelini (HEASARC/GSFC)
- ID:
- ivo://CDS.VizieR/IX/31
- Title:
- The WGACAT version of ROSAT sources
- Short Name:
- IX/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- WGACAT is a point source catalogue generated from all ROSAT PSPC (Position Sensitive Proportional Counter) pointed observations. This catalog has been generated by N.E. White (HEASARC/GSFC), P. Giommi (SDC/ASI) and L. Angelini (HEASARC/GSFC) and is a private research effort, not related to the official catalogs generated by the ROSAT project. The WGACAT was made first publicly available in November 1994 through the HEASARC on-line service (White, Giommi and Angelini 1994), with a first minor revision in March 1995 (WGACAT95). It was generated using all the public ROSAT PSPC pointed data available than, corresponding to 75% of the entire set, and featured ~ 68000 detections of which 62000 were unique sources. The current version, released in May 2000, is the final and complete version of WGACAT and includes the remaining sequences not processed in the WGACAT95. WGACAT (May 2000) contains about 88,000 detections, with more than 84,000 individual sources, obtained from 4160 sequences. The catalog was generated using an optimized sliding cell detect algorithm in XIMAGE (first developed for the EXOSAT project). The inner and outer parts of the images were run separately, to maximize the sensitivity to source detection. This method is very sensitive in finding point sources, but can also find spurious sources where there is extended emission. We have visually inspected each detection, removed the obvious spurious cases and assigned a quality flag to each detection.
- ID:
- ivo://CDS.VizieR/J/ApJ/708/1076
- Title:
- The WHIQII survey: compact blue galaxies
- Short Name:
- J/ApJ/708/1076
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of the WIYN High Image Quality Indiana-Irvine (WHIQII) survey, we present 123 spectra of faint emission-line galaxies, selected to focus on intermediate redshift (0.4<~z<~0.8) galaxies with blue colors that appear physically compact on the sky. The sample includes 15 true Luminous Compact Blue Galaxies (LCBGs) and an additional 27 slightly less extreme emission-line systems. These galaxies represent a highly evolving class that may play an important role in the decline of star formation since z~1, but their exact nature and evolutionary pathways remain a mystery. Here, we use emission lines to determine metallicities and ionization parameters, constraining their intrinsic properties and state of star formation. Some LCBG metallicities are consistent with a "bursting dwarf" scenario, while a substantial fraction of others are not, further confirming that LCBGs are a highly heterogeneous population but are broadly consistent with the intermediate redshift field. In agreement with previous studies, we observe overall evolution in the luminosity-metallicity relation at intermediate redshift. Our sample, and particularly the LCBGs, occupies a region in the empirical R_23_-O_32_ plane that differs from luminous local galaxies and is more consistent with dwarf irregulars at the present epoch, suggesting that cosmic "downsizing" is observable in even the most fundamental parameters that describe star formation.
19210. The 2WHSP catalog
- ID:
- ivo://CDS.VizieR/J/A+A/598/A17
- Title:
- The 2WHSP catalog
- Short Name:
- J/A+A/598/A17
- Date:
- 04 Feb 2022 11:56:24
- Publisher:
- CDS
- Description:
- High Synchrotron Peaked blazars (HSPs) dominate the gamma sky at energies larger than a few GeV; however, only a few hundred blazars of this type have been catalogued so far. In this paper we present the 2WHSP sample, the largest and most complete list of HSP blazars available to date, which is an expansion of the 1WHSP catalog of gamma-ray source candidates off the Galactic plane. We cross-matched a number of multi-wavelength surveys (in the radio, infrared and X-ray bands) and applied selection criteria based on the radio to IR and IR to X-ray spectral slopes. To ensure the selection of genuine HSPs we examined the SED of each candidate and estimated the peak frequency of its synchrotron emission ({nu}_peak_) using the ASDC SED tool, including only sources with {nu}_peak_>10^15^Hz (equivalent to {nu}_peak_>4eV). We have assembled the largest and most complete catalog of HSP blazars to date, which includes 1691 sources. A number of population properties, such as infrared colours, synchrotron peak, redshift distributions, and gamma-ray spectral properties, have been used to characterise the sample and maximize completeness. We also derived the radio logN-logS distribution. This catalog has already been used to provide seeds to discover new very high energy objects within Fermi-LAT data and to look for the counterparts of neutrino and ultra high energy cosmic ray sources, showing its potential for the identification of promising high-energy gamma, sources and multi-messenger targets.