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511. 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.
512. 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:
14 Feb 2025
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 .
513. 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.
514. 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.
515. 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:
27 Dec 2024 08:31:06
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.
516. A debris disk study of Praesepe
ID:
ivo://CDS.VizieR/J/ApJ/697/1578
Title:
A debris disk study of Praesepe
Short Name:
J/ApJ/697/1578
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 24um photometry of the intermediate-age open cluster Praesepe. We assemble a catalog of 193 probable cluster members that are detected in optical databases, the Two Micron All Sky Survey (2MASS), and at 24um, within an area of ~2.47deg^2^. Mid-IR excesses indicating debris disks are found for one early-type and for three solar-type stars. Corrections for sampling statistics yield a 24um excess fraction (debris disk fraction) of 6.5%+/-4.1% for luminous and 1.9%+/-1.2% for solar-type stars. The incidence of excesses is in agreement with the decay trend of debris disks as a function of age observed for other cluster and field stars.
517. A deep catalogue of classical Be stars
ID:
ivo://CDS.VizieR/J/MNRAS/446/274
Title:
A deep catalogue of classical Be stars
Short Name:
J/MNRAS/446/274
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of 247 photometrically and spectroscopically confirmed fainter classical Be stars (13<r<16) in the direction of the Perseus Arm of the Milky Way (1{deg}<b<+4{deg}, 120{deg}<l<140{deg}). The catalogue consists of 181 IPHAS-selected new classical Be stars, in addition to 66 objects that we studied in our previous work more closely, and three stars identified as classical Be stars in earlier work. This study more than doubles the number known in the region. Photometry spanning 0.6-5um, spectral types, and interstellar reddenings are given for each object. The spectral types were determined from low-resolution spectra ({lambda}/{Delta}_{lambda}~800-2000), to a precision of 1-3 subtypes. The interstellar reddenings are derived from the (r-i) colour, using a method that corrects for circumstellar disc emission. The colour excesses obtained range from E(B-V)=0.3 up to 1.6 a distribution that modestly extends the range reported in the literature for Perseus-Arm open clusters. For around half the sample, the reddenings obtained are compatible with measures of the total sightline Galactic extinction. Many of these are likely to lie well beyond the Perseus Arm.
518. A deep Chandra ACIS survey of M51
ID:
ivo://CDS.VizieR/J/ApJ/827/46
Title:
A deep Chandra ACIS survey of M51
Short Name:
J/ApJ/827/46
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have obtained a deep X-ray image of the nearby galaxy M51 using Chandra. Here we present the catalog of X-ray sources detected in these observations and provide an overview of the properties of the point-source population. We find 298 sources within the D_25_ radii of NGC 5194/5, of which 20% are variable, a dozen are classical transients, and another half dozen are transient-like sources. The typical number of active ultraluminous X-ray sources in any given observation is ~5, and only two of those sources persist in an ultraluminous state over the 12yr of observations. Given reasonable assumptions about the supernova remnant population, the luminosity function is well described by a power law with an index between 1.55 and 1.7, only slightly shallower than that found for populations dominated by high-mass X-ray binaries (HMXBs), which suggests that the binary population in NGC 5194 is also dominated by HMXBs. The luminosity function of NGC 5195 is more consistent with a low-mass X-ray binary dominated population.
519. A deep Chandra ACIS survey of M83
ID:
ivo://CDS.VizieR/J/ApJS/212/21
Title:
A deep Chandra ACIS survey of M83
Short Name:
J/ApJS/212/21
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have obtained a series of deep X-ray images of the nearby galaxy M83 using Chandra, with a total exposure of 729ks. Combining the new data with earlier archival observations totaling 61ks, we find 378 point sources within the D_25_ contour of the galaxy. We find 80 more sources, mostly background active galactic nuclei (AGNs), outside of the D_25_contour. Of the X-ray sources, 47 have been detected in a new radio survey of M83 obtained using the Australia Telescope Compact Array. Of the X-ray sources, at least 87 seem likely to be supernova remnants (SNRs), based on a combination of their properties in X-rays and at other wavelengths. We attempt to classify the point source population of M83 through a combination of spectral and temporal analysis. As part of this effort, we carry out an initial spectral analysis of the 29 brightest X-ray sources. The soft X-ray sources in the disk, many of which are SNRs, are associated with the spiral arms, while the harder X-ray sources, mostly X-ray binaries (XRBs), do not appear to be. After eliminating AGNs, foreground stars, and identified SNRs from the sample, we construct the cumulative luminosity function (CLF) of XRBs brighter than 8x10^35^erg/s. Despite M83's relatively high star formation rate, the CLF indicates that most of the XRBs in the disk are low mass XRBs.
520. A deep HST H-band imaging survey. II. QUEST QSOs
ID:
ivo://CDS.VizieR/J/ApJ/701/587
Title:
A deep HST H-band imaging survey. II. QUEST QSOs
Short Name:
J/ApJ/701/587
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results from a deep Hubble Space Telescope (HST) NICMOS H-band imaging survey of 28 z<0.3 QSOs from the Palomar-Green (PG) sample. This program is part of QUEST (Quasar/ULIRG Evolution Study) and complements a similar set of data on 26 highly nucleated ULIRGs presented in Paper I (Veilleux et al. 2006ApJ...643..707V). Our analysis indicates that the fraction of QSOs with elliptical hosts is higher among QSOs with undetected far-infrared (FIR) emission, small infrared excess (L_IR_/L_B_<10), and luminous hosts. The hosts of FIR-faint QSOs show a tendency to have less pronounced merger-induced morphological anomalies and larger QSO-to-host luminosity ratios on average than the hosts of FIR-bright QSOs, consistent with late-merger evolution from FIR-bright to FIR-faint QSOs.

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