- ID:
- ivo://CDS.VizieR/J/ApJ/699/839
- Title:
- Newly identified star clusters in M33. II.
- Short Name:
- J/ApJ/699/839
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present integrated photometry and color-magnitude diagrams (CMDs) for 161 star clusters in M33, of which 115 were previously uncataloged, using the Advanced Camera For Surveys Wide Field Channel onboard the Hubble Space Telescope. The integrated V-band magnitudes of these clusters range from M_V_~-9 to as faint as M_V_~-4, extending the depth of the existing M33 cluster catalogs by ~1mag. Comparisons of theoretical isochrones to the CMDs using the Padova models yield ages for 148 of these star clusters. The ages range from log(t)~7.0 to log(t)~9.0. Our CMDs are not sensitive to clusters older than ~1Gyr. We find that the variation of the clusters' integrated colors and absolute magnitudes with age is consistent with the predictions of simple stellar population models. These same models suggest that the masses of the clusters in our sample range from 5x10^3^ to 5x10^4^M_{sun}_.
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- ID:
- ivo://CDS.VizieR/J/ApJ/753/27
- Title:
- New point sources in the WMAP 7yr data
- Short Name:
- J/ApJ/753/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have developed a new needlet-based method to detect point sources in cosmic microwave background (CMB) maps and have applied it to the Wilkinson Microwave Anisotropy Probe (WMAP) 7 year data. We use both the individual frequency channels as well as internal templates, the latter being the difference between pairs of frequency channels and hence having the advantage that the CMB component is eliminated. Using the area of the sky outside the Kq85 galactic mask, we detect a total of 2102 point sources at the 5{sigma} level in either the frequency maps or the internal templates. Of these, 1116 are detected either at 5{sigma} directly in the frequency channels or at 5{sigma} in the internal templates and >=3{sigma} at the corresponding position in the frequency channels. Of the 1116 sources, 603 are detections that have not been reported so far in WMAP data. We have made a catalog of these sources available with position and flux estimated in the WMAP channels where they are seen. In total, we identified 1029 of the 1116 sources with counterparts at 5GHz and 69 at other frequencies.
- ID:
- ivo://CDS.VizieR/J/ApJ/586/814
- Title:
- NGC 4472 Chandra/HST study
- Short Name:
- J/ApJ/586/814
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a Chandra/Hubble Space Telescope (HST) study of the point sources of the Virgo Cluster giant elliptical galaxy NGC 4472. We identify 144 X-ray point sources outside the nuclear region, 72 of which are located within the HST fields. The optical data show 1102 sources, of which 829 have colors consistent with being globular clusters (with only four in the restricted central 10" region). Thirty matches are found between the two lists - these are likely to be low-mass X-ray binaries (LMXBs) associated with globular clusters, while ~42 of the X-ray sources have no optical counterparts to V<~25 and I<~24, indicating that they are likely to be predominantly LMXBs in the field star population with a small amount of possible contamination from background active galactic nuclei. Thus approximately 40% of the X-ray sources are in globular clusters and 4% of the globular clusters contain X-ray sources.
- ID:
- ivo://CDS.VizieR/J/ApJS/175/86
- Title:
- NGP+30{deg} zone galaxies I.
- Short Name:
- J/ApJS/175/86
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A database containing 618 active and star-forming (A/SF) galaxies and 564 normal galaxies in a 120{deg}x6{deg} wide strip crossing the North Galactic Pole was constructed in order to compare the global properties of "active" galaxies against a control sample of "normal" galaxies. This database combines a literature and catalog search with new optical measurements from the Fpg (red) and Jpg (blue) band images of the STScI Digitized Sky Survey (DSS). We provide alternative names, accurate coordinates, morphological type, activity classes, red and blue apparent magnitudes, 2MASS near-infrared J-H and H-K colors, apparent diameters, axial ratios, position angles, and number counts of neighboring objects in a circle of radius 50kpc. We also present an atlas of 103 interacting and merging systems among these galaxies. In this sample, all merging and interacting galaxies are A/SF objects. The near-infrared colors of the sample galaxies are independent parameters and do not correlate with activity level or any other parameter of the galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/890/128
- Title:
- NGVS. XIV. Bona fide Virgo cluster members
- Short Name:
- J/ApJ/890/128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Next Generation Virgo Cluster Survey (NGVS) was designed to provide a deep census of baryonic structures in the Virgo cluster. The survey covers the 104deg^2^ area from the core of Virgo out to one virial radius, in the u*griz bandpasses, to a point-source depth of g~25.9mag (10{sigma}) and a single pixel surface brightness limit of {mu}_g_~29mag/arcsec^2^ (2{sigma} above the sky). Here we present the final catalog of 404 Virgo galaxies located within a 3.71deg^2^ (0.3Mpc^2^) region centered on M87, Virgo's dominant galaxy. Of these, 154 were previously uncataloged and span the range 17.8mag<g<23.7mag (-13.4mag<M_g_{<}-7.4mag at the 16.5Mpc distance of Virgo). Extensive simulations show that the NGVS catalog is complete down to g=18.6mag (M_g_=-12.5mag, corresponding to a stellar mass M~1.6x10^7^M_{sun}_ for an old stellar population), and 50% complete at g=22.0mag (M_g_=-9.1mag, M~6.2x10^5^M_{sun}_). The NGVS 50% completeness limit is 3mag deeper than that of the Virgo Cluster Catalog (VCC), which has served as Virgo's reference standard for over a quarter century, and 2mag deeper than the VCC detection limit. We discuss the procedure adopted for the identification of objects and the criteria used to assess cluster membership. For each of the 404 galaxies in the NGVS Virgo Cluster core catalog, we present photometric and structural parameters based on a nonparametric curve-of-growth and isophotal analysis, as well as parametric (Sersic, double-Sersic, and/or core-Sersic) fits to the one-dimensional surface brightness profiles and two-dimensional light distributions.
- ID:
- ivo://CDS.VizieR/J/ApJS/208/20
- Title:
- Nine-year WMAP point source catalogs
- Short Name:
- J/ApJS/208/20
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the final nine-year maps and basic results from the Wilkinson Microwave Anisotropy Probe (WMAP) mission. The full nine-year analysis of the time-ordered data provides updated characterizations and calibrations of the experiment. We also provide new nine-year full sky temperature maps that were processed to reduce the asymmetry of the effective beams. Temperature and polarization sky maps are examined to separate cosmic microwave background (CMB) anisotropy from foreground emission, and both types of signals are analyzed in detail. We provide new point source catalogs as well as new diffuse and point source foreground masks. An updated template-removal process is used for cosmological analysis; new foreground fits are performed, and new foreground-reduced CMB maps are presented.
- ID:
- ivo://CDS.VizieR/I/293
- Title:
- NPM2 Cross-Identifications
- Short Name:
- I/293
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Lick NPM2 Catalog provides absolute proper motions, positions, and photographic photometry, measured in the Lick Northern Proper Motion (NPM) program, for 232,062 stars in the magnitude range 8<B<18, covering the sky within the Milky Way north of -23deg declination. The NPM2 Cross-Identifications file provides 46,887 cross-identifications between the NPM2 Catalog numbers and star names, stellar type classifications, and publication references. These additional data, extracted from Klemola's Lick Input Catalog of Special Stars (ICSS), facilitate many practical uses of the NPM2 Catalog. Five Appendices to the NPM2 Catalog provide references, footnotes, and other useful information. This "ReadMe" file explains the file formats. Detailed documentation is given in the file "npm2cros.txt".
- ID:
- ivo://CDS.VizieR/I/214
- Title:
- NPM1 Cross-Identifications and Appendices
- Short Name:
- I/214
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The NPM1 Catalog provides absolute proper motions, positions, and photographic photometry, measured in the Lick Northern Proper Motion (NPM) program, for some 149,000 stars in the magnitude range 8<B<18mag, covering the sky outside the Milky Way north of -23{deg} declination. The NPM1 Cross-Identifications file provides some 42,000 cross-identifications between the NPM1 Catalog numbers and star names, stellar type classifications, and publication references. These additional data, extracted from the Lick Input Catalog of Special Stars, facilitate many practical uses of the NPM1 Catalog. Six Appendices to the NPM1 Catalog provide references, footnotes, and other useful information.
- ID:
- ivo://CDS.VizieR/J/MNRAS/508/5176
- Title:
- NuSTAR Extragalactic Surveys, NEP Field
- Short Name:
- J/MNRAS/508/5176
- Date:
- 03 Dec 2021 13:27:09
- Publisher:
- CDS
- Description:
- We present the NuSTAR extragalactic survey of the James Webb Space Telescope (JWST) North Ecliptic Pole (NEP) Time-Domain Field. The survey covers a ~0.16deg^2^ area with a total exposure of 681ks acquired in a total of nine observations from three epochs. The survey sensitivities at 20% of the area are 2.39, 1.14, 2.76, 1.52, and 5.20x10^-14^erg/cm^2^/s in the 3-24, 3-8, 8-24, 8-16, and 16-24keV bands, respectively. The NEP survey is one of the most sensitive extragalactic surveys with NuSTAR so far. A total of 33 sources were detected above 95% reliability in at least one of the five bands. We present the number counts, logN-logS, measured in the hard X-ray 8-24 and 8-16keV bands, uniquely accessible by NuSTAR down to such faint fluxes. We performed source detection on the XMM-Newton and Chandra observations of the same field to search for soft X-ray counterparts of each NuSTAR detection. The soft band positions were used to identify optical and infrared associations. We present the X-ray properties (hardness ratio and luminosity) and optical-to-X-ray properties of the detected sources. The measured fraction of candidate Compton-thick (NH>=10^24^cm^-2^) active galactic nuclei, derived from the hardness ratio, is between 3% to 27%. As this survey was designed to have variability as its primary focus, we present preliminary results on multi-epoch flux variability in the 3-24keV band.
- ID:
- ivo://CDS.VizieR/J/ApJS/235/17
- Title:
- NuSTAR Extragalactic Surveys: UDS field
- Short Name:
- J/ApJS/235/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results and the source catalog of the NuSTAR survey in the UKIDSS Ultra Deep Survey (UDS) field, bridging the gap in depth and area between NuSTAR's ECDFS and COSMOS surveys. The survey covers a ~0.6deg^2^ area of the field for a total observing time of ~1.75Ms, to a half-area depth of ~155ks corrected for vignetting at 3-24keV, and reaching sensitivity limits at half-area in the full (3-24keV), soft (3-8keV), and hard (8-24keV) bands of 2.2x10^-14^erg/cm^2^/s, 1.0x10^-14^erg/cm^2^/s, and 2.7x10^-14^erg/cm^2^/s, respectively. A total of 67 sources are detected in at least one of the three bands, 56 of which have a robust optical redshift with a median of <z>~1.1. Through a broadband (0.5-24keV) spectral analysis of the whole sample combined with the NuSTAR hardness ratios, we compute the observed Compton-thick (CT; N_H_>10^24^cm^-2^) fraction. Taking into account the uncertainties on each NH measurement, the final number of CT sources is 6.8+/-1.2. This corresponds to an observed CT fraction of 11.5%+/-2.0%, providing a robust lower limit to the intrinsic fraction of CT active galactic nuclei and placing constraints on cosmic X-ray background synthesis models.
