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511. Activity type of AGN with SDSS spectra
ID:
ivo://CDS.VizieR/J/other/Ap/63.322
Title:
Activity type of AGN with SDSS spectra
Short Name:
J/other/Ap/63.32
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is a detailed spectral classification of 96 active galaxies from the Veron-Cetty and Veron catalog (2010, Version 13, Cat. VII/258) of active galaxies and quasars. These objects were identified as radio sources using standard radio catalogs. Those galaxies which had radio sources in at least 6 different radio bands and had been identified spectrally in the SDSS catalog were selected. The types of activity of these were determined using their SDSS spectra. Three diagnostic diagrams and a direct study of the spectra were used for more certain classification. As a result, the classifications of 85% of the objects were changed. The radio sources in different radio bands make it possible to construct the spectral distribution of the energy in the radio range and to compare it with the optical activity types.
512. Activity types of ROSAT/SDSS galaxies
ID:
ivo://CDS.VizieR/J/other/Ap/62.147
Title:
Activity types of ROSAT/SDSS galaxies
Short Name:
J/other/Ap/62.14
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this study we carry out detailed spectral classification of 173 AGN candidates from the Joint HRC/BHRC sample, which is a combination of HRC (Hamburg-ROSAT Catalogue) and BHRC (Byurakan-Hamburg-ROSAT Catalogue). These objects were revealed as optical counterparts for ROSAT X-ray sources, however spectra for 173 of them are given in SDSS without definite spectral classification. We studied these 173 objects using the SDSS spectra and revealed the detailed activity types for them. Three diagnostic diagrams and direct examination of the spectra were used to have more confident classification. We also made identification of these sources in other wavelength ranges and calculated some of their parameters.
513. ACT/MaDCoWS clusters co-detections
ID:
ivo://CDS.VizieR/J/A+A/653/A135
Title:
ACT/MaDCoWS clusters co-detections
Short Name:
J/A+A/653/A135
Date:
08 Feb 2022 13:59:57
Publisher:
CDS
Description:
Galaxy clusters are an important tool for cosmology, and their detection and characterization are key goals for current and future surveys. Using data from the Wide-field Infrared Survey Explorer (WISE), the Massive and Distant Clusters of WISE Survey (MaDCoWS) located 2839 significant galaxy overdensities at redshifts 0.7<=z<=1.5, which included extensive follow-up imaging from the Spitzer Space Telescope to determine cluster richnesses. Concurrently, the Atacama Cosmology Telescope (ACT) has produced large area millimeter-wave maps in three frequency bands along with a large catalog of Sunyaev-Zeldovich (SZ)-selected clusters as part of its Data Release 5 (DR5). We aim to verify and characterize MaDCoWS clusters using measurements of, or limits on, their thermal SZ effect signatures. We also use these detections to establish the scaling relation between SZ mass and the MaDCoWS-defined richness. Using the maps and cluster catalog from DR5, we explore the scaling between SZ mass and cluster richness. We do this by comparing cataloged detections and extracting individual and stacked SZ signals from the MaDCoWS cluster locations. We use complementary radio survey data from the Very Large Array, submillimeter data from Herschel, and ACT 224GHz data to assess the impact of contaminating sources on the SZ signals from both ACT and MaDCoWS clusters. We use a hierarchical Bayesian model to fit the mass-richness scaling relation, allowing for clusters to be drawn from two populations: one, a Gaussian centered on the mass-richness relation, and the other, a Gaussian centered on zero SZ signal. We find that MaDCoWS clusters have submillimeter contamination that is consistent with a gray-body spectrum, while the ACT clusters are consistent with no submillimeter emission on average. Additionally, the intrinsic radio intensities of ACT clusters are lower than those of MaDCoWS clusters, even when the ACT clusters are restricted to the same redshift range as the MaDCoWS clusters. We find the best-fit ACT SZ mass versus MaDCoWS richness scaling relation has a slope of p1=1.84_-0.14_^+0.15^, where the slope is defined as M{lambda}{prop.to}{lambda}_15_^p1^ and {lambda}_15_ is the richness. We also find that the ACT SZ signals for a significant fraction (~57%) of the MaDCoWS sample can statistically be described as being drawn from a noise-like distribution, indicating that the candidates are possibly dominated by low-mass and unvirialized systems that are below the mass limit of the ACT sample. Further, we note that a large portion of the optically confirmed ACT clusters located in the same volume of the sky as MaDCoWS are not selected by MaDCoWS, indicating that the MaDCoWS sample is not complete with respect to SZ selection. Finally, we find that the radio loud fraction of MaDCoWS clusters increases with richness, while we find no evidence that the submillimeter emission of the MaDCoWS clusters evolves with richness. We conclude that the original MaDCoWS selection function is not well defined and, as such, reiterate the MaDCoWS collaboration's recommendation that the sample is suited for probing cluster and galaxy evolution, but not cosmological analyses. We find a best-fit mass-richness relation slope that agrees with the published MaDCoWS preliminary results. Additionally, we find that while the approximate level of infill of the ACT and MaDCoWS cluster SZ signals (1-2%) is subdominant to other sources of uncertainty for current generation experiments, characterizing and removing this bias will be critical for next-generation experiments hoping to constrain cluster masses at the sub-percent level.
514. ACT Massive and Distant Clusters of WISE Survey (MaDCoWS) Candidates Catalog
ID:
ivo://nasa.heasarc/actmadcows
Title:
ACT Massive and Distant Clusters of WISE Survey (MaDCoWS) Candidates Catalog
Short Name:
ACTMADCOWS
Date:
08 Nov 2024
Publisher:
NASA/GSFC HEASARC
Description:
Galaxy clusters are an important tool for cosmology, and their detection and characterization are key goals for current and future surveys. Using data from the Wide-field Infrared Survey Explorer (WISE), the Massive and Distant Clusters of WISE Survey (MaDCoWS) located 2839 significant galaxy overdensities at redshifts 0.7 &lt;= z &lt;= 1.5, which included extensive follow-up imaging from the Spitzer Space Telescope to determine cluster richnesses. Concurrently, the Atacama Cosmology Telescope (ACT) has produced large area millimeter-wave maps in three frequency bands along with a large catalog of Sunyaev-Zel&#39;dovich (SZ)-selected clusters as part of its Data Release 5 (DR5). The authors aimed to verify and characterize MaDCoWS clusters using measurements of, or limits on, their thermal SZ effect signatures. They also used these detections to establish the scaling relation between SZ mass and the MaDCoWS-defined richness. Using the maps and cluster catalog from DR5, the authors explore the scaling between SZ mass and cluster richness. They do this by comparing cataloged detections and extracting individual and stacked SZ signals from the MaDCoWS cluster locations. The authors use complementary radio survey data from the Very Large Array, submillimeter data from Herschel, and ACT 224GHz data to assess the impact of contaminating sources on the SZ signals from both ACT and MaDCoWS clusters. They use a hierarchical Bayesian model to fit the mass-richness scaling relation, allowing for clusters to be drawn from two populations: one, a Gaussian centered on the mass-richness relation, and the other, a Gaussian centered on zero SZ signal. This study found that MaDCoWS clusters have submillimeter contamination that is consistent with a gray-body spectrum, while the ACT clusters are consistent with no submillimeter emission on average. Additionally, the intrinsic radio intensities of ACT clusters are lower than those of MaDCoWS clusters, even when the ACT clusters are restricted to the same redshift range as the MaDCoWS clusters. The authors found the best-fit ACT SZ mass versus MaDCoWS richness scaling relation has a slope of p1=1.84&lt;sub&gt;-0.14&lt;/sub&gt;&lt;sup&gt;+0.15&lt;/sup&gt;, where the slope is defined as M ~lambda&lt;sub&gt;15&lt;/sub&gt;&lt;sup&gt;p1&lt;/sup&gt; and lambda&lt;sub&gt;15&lt;/sub&gt; is the richness. They also found that the ACT SZ signals for a significant fraction (~57%) of the MaDCoWS sample can statistically be described as being drawn from a noise-like distribution, indicating that the candidates are possibly dominated by low-mass and unvirialized systems that are below the mass limit of the ACT sample. Further, the authors noted that a large portion of the optically confirmed ACT clusters located in the same volume of the sky as MaDCoWS were not selected by MaDCoWS, indicating that the MaDCoWS sample is not complete with respect to SZ selection. Finally, the authors found that the radio loud fraction of MaDCoWS clusters increases with richness, while they found no evidence that the submillimeter emission of the MaDCoWS clusters evolved with richness. The authors concluded that the original MaDCoWS selection function is not well defined and, as such, reiterated the MaDCoWS collaboration&#39;s recommendation that the sample is suited for probing cluster and galaxy evolution, but not cosmological analyses. They found a best-fit mass-richness relation slope that agrees with the published MaDCoWS preliminary results. Additionally, they concluded that, while the approximate level of infill of the ACT and MaDCoWS cluster SZ signals (1-2%) is subdominant to other sources of uncertainty for current generation experiments, characterizing and removing this bias will be critical for next-generation experiments hoping to constrain cluster masses at the sub-percent level. This table was created by the HEASARC in April 2022 based upon the link provided by the LAMBDA archive: &lt;a href="https://lambda.gsfc.nasa.gov/product/act/actpol_madcows_cl_catalog_get.html"&gt;https://lambda.gsfc.nasa.gov/product/act/actpol_madcows_cl_catalog_get.html&lt;/a&gt;. This is a service provided by NASA HEASARC .
515. ACV variables in the Zwicky Transient Facility
ID:
ivo://CDS.VizieR/J/A+A/656/A125
Title:
ACV variables in the Zwicky Transient Facility
Short Name:
J/A+A/656/A125
Date:
16 Mar 2022 00:55:18
Publisher:
CDS
Description:
The present work presents a case study of known variables from the Zwicky Transient Facility (ZTF) survey, with the aim of investigating the survey's suitability for the detection and study of new ACV variables. Using suitable selection criteria based on the known characteristics of ACV variables, candidate ACV stars were selected from the ZTF Catalog of Periodic Variable Stars. All light curves were inspected in detail to select the most promising candidates. Where available, low-resolution spectra from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) were employed to classify the stars on the MK system and confirm their status as mCP stars. We have identified 86 new promising ACV star candidates. 15 of these stars have LAMOST spectra available, which, in all cases, confirm them as classical mCP stars, which highlights the viability of our approach. We present astrophysical parameters for all sample stars, which can be sorted into four subgroups characterized by distinct light curve shapes. Anti-phase variations in different photometric passbands, in particular, is a unique characteristic of a subset of ACV stars readily usable for their identification. The availability of data in three different passbands (g, r, and i) is a major advantage of the ZTF survey. On the basis of our experience with other photometric surveys and the analysis of light curves, we conclude that the ZTF is well suited for the search for, and the analysis of, ACV variables, which, however, are not considered in the available ZTF variable star catalogues. Further work will be concerned with the development and refinement of a search algorithm to correctly identify these stars in ZTF data and, subsequently, in massive photometric time-series databases in general.
516. A Database of Circumstellar OH Masers
ID:
ivo://org.gavo.dc/ohmaser/q/scs
Title:
A Database of Circumstellar OH Masers
Short Name:
engels ohmasers
Date:
15 Aug 2024 15:17:00
Publisher:
The GAVO DC team
Description:
A all-sky compilation of galactic stellar sources observed for OH maser emission in the transitions at 1612, 1665, and 1667 MHz. The database contains OH maser observations selected from the literature . These observations belong to more than 6000 different objects. The database consists of three tables: The main table ("masers"), interferometric followup observations ("maps") and monitoring programs ("monitor").
517. A Database of Circumstellar OH Masers: Interferometric Followups
ID:
ivo://org.gavo.dc/ohmaser/q/mapscs
Title:
A Database of Circumstellar OH Masers: Interferometric Followups
Short Name:
engels oh maps
Date:
15 Aug 2024 15:17:00
Publisher:
The GAVO DC team
Description:
A all-sky compilation of galactic stellar sources observed for OH maser emission in the transitions at 1612, 1665, and 1667 MHz. The database contains OH maser observations selected from the literature . These observations belong to more than 6000 different objects. The database consists of three tables: The main table ("masers"), interferometric followup observations ("maps") and monitoring programs ("monitor").
518. A Database of Circumstellar OH Masers: Monitoring Programs
ID:
ivo://org.gavo.dc/ohmaser/q/monscs
Title:
A Database of Circumstellar OH Masers: Monitoring Programs
Short Name:
engels oh mon
Date:
15 Aug 2024 15:17:00
Publisher:
The GAVO DC team
Description:
A all-sky compilation of galactic stellar sources observed for OH maser emission in the transitions at 1612, 1665, and 1667 MHz. The database contains OH maser observations selected from the literature . These observations belong to more than 6000 different objects. The database consists of three tables: The main table ("masers"), interferometric followup observations ("maps") and monitoring programs ("monitor").
519. A database of dense cores mapped in ammonia
ID:
ivo://CDS.VizieR/J/ApJS/125/161
Title:
A database of dense cores mapped in ammonia
Short Name:
J/ApJS/125/161
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a database of 264 cores mapped in the (J,K)=(1,1) and (2,2) lines of NH_3_. We list the core gas properties-peak positions, total ammonia column densities, intrinsic line widths, kinetic temperatures, volume densities, core sizes, aspect ratios, and velocity gradients, as well as the properties of associated young stellar objects (YSOs)-associated IRAS sources along with their luminosities and core-YSO distances, outflow velocities, and SIMBAD and cluster associations. We also present the results of our statistical analysis and enumerate important pairwise correlations among the various gas and YSO properties.
520. Adding catalog data to object lists using the VO
ID:
ivo://edu.gavo.org/hd/gavo_addpms
Title:
Adding catalog data to object lists using the VO
Date:
15 Aug 2024 15:17:04
Publisher:
The GAVO DC team
Description:
This brief tutorial shows you how to quickly add proper motions and photometry from Gaia to (almost) any object list using the Virtual Observatory. The VO protocol most suited to this kind of this is TAP ("table access protocol") and lets you transfer data and queries to database servers. In the example, we will be using TOPCAT as a client. There is no lock-in to it: There are libraries and other tools allowing an integration of TAP operations into arbitrary workflows – that's what standards are about. Tutorial supplements apply the techniques to Simbad, show how to use TAP from Python, and introduce UCDs.

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