- ID:
- ivo://CDS.VizieR/J/ApJ/759/6
- Title:
- SEDs of type I AGN in COSMOS. I. XMM-COSMOS
- Short Name:
- J/ApJ/759/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The "Cosmic Evolution Survey" (COSMOS) enables the study of the spectral energy distributions (SEDs) of active galactic nuclei (AGNs) because of the deep coverage and rich sampling of frequencies from X-ray to radio. Here we present an SED catalog of 413 X-ray (XMM-Newton)-selected type 1 (emission line FWHM>2000km/s) AGNs with Magellan, SDSS, or VLT spectrum. The SEDs are corrected for Galactic extinction, broad emission line contributions, constrained variability, and host galaxy contribution. We present the mean SED and the dispersion SEDs after the above corrections in the rest-frame 1.4GHz to 40keV, and show examples of the variety of SEDs encountered. In the near-infrared to optical (rest frame ~8{mu}m-4000{AA}), the photometry is complete for the whole sample and the mean SED is derived from detections only. Reddening and host galaxy contamination could account for a large fraction of the observed SED variety.
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- ID:
- ivo://CDS.VizieR/J/ApJS/187/135
- Title:
- SEDs of weak AGNs associated with LINERs
- Short Name:
- J/ApJS/187/135
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a compilation of spectral energy distributions (SEDs) of 35 weak active galactic nuclei (AGNs) in low-ionization nuclear emission regions (LINERs) using recent data from the published literature. We make use of previously published compilations of data, after complementing and extending them with more recent data. The main improvement in the recent data is afforded by high-spatial-resolution observations with the Chandra X-Ray Observatory and high spatial resolution radio observations utilizing a number of facilities. In addition, a considerable number of objects have been observed with the Hubble Space Telescope in the near-IR through near-UV bands since the earlier compilations were published. The data include upper limits resulting from either non-detections or observations at low spatial resolution that do not isolate the AGN. For the sake of completeness, we also compute and present a number of quantities from the data, such as optical-to-X-ray spectral indices ({alpha}_ox_), bolometric corrections, bolometric luminosities, Eddington ratios, and the average SED. We anticipate that these data will be useful for a number of applications. In a companion paper, we use a subset of these data ourselves to assess the energy budgets of LINERs.
843. SEXSI catalog
- ID:
- ivo://CDS.VizieR/J/ApJ/596/944
- Title:
- SEXSI catalog
- Short Name:
- J/ApJ/596/944
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Serendipitous Extragalactic X-Ray Source Identification (SEXSI) program is designed to extend greatly the sample of identified extragalactic hard X-ray (2-10keV) sources at intermediate fluxes (~10^-13^ to 10^-15^erg/cm^2^/s). SEXSI, which studies sources selected from more than 2deg^2^, provides an essential complement to the Chandra Deep Fields, which reach depths of 5x10^-16^erg/cm^2^/s (2-10keV) but over a total area of less than 0.2deg^2^. In this paper we describe the characteristics of the survey and our X-ray data analysis methodology. We present the cumulative flux distribution for the X-ray sample of 1034 hard sources and discuss the distribution of spectral hardness ratios. Our logN-logS in this intermediate flux range connects to those found in the Deep Fields, and by combining the data sets, we constrain the hard X-ray population over the flux range in which the differential number counts change slope and from which the bulk of the 2-10keV X-ray background arises. We further investigate the logN-logS distribution separately for soft and hard sources in our sample, finding that while a clear change in slope is seen for the softer sample, the hardest sources are well described by a single power law down to the faintest fluxes, consistent with the notion that they lie at lower average redshift.
844. SEXSI catalog. II
- ID:
- ivo://CDS.VizieR/J/ApJS/156/35
- Title:
- SEXSI catalog. II
- Short Name:
- J/ApJS/156/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Serendipitous Extragalactic X-ray Source Identification (SEXSI) Program is designed to expand significantly the sample of identified extragalactic hard X-ray sources at intermediate fluxes, 10^-13^ergs/cm^2^/s<~S_2-10keV_<10^-15^ergs/cm^2^/s. SEXSI, which includes sources derived from more than 2{deg}^2^ of Chandra images, provides the largest hard X-ray-selected sample yet studied, offering an essential complement to the Chandra Deep Fields (total area 0.2{deg}^2^). In this paper we describe R-band optical imaging of the SEXSI fields from the Palomar, MDM, and Keck observatories. We have identified counterparts or derived flux limits for nearly 1000 hard X-ray sources. Using the optical images, we derive accurate source positions. We investigate correlations between optical and X-ray flux, and optical flux and X-ray hardness ratio. We also study the density of optical sources surrounding X-ray counterparts, as well as the properties of optically faint, hard X-ray sources.
845. SEXSI catalog. III
- ID:
- ivo://CDS.VizieR/J/ApJS/165/19
- Title:
- SEXSI catalog. III
- Short Name:
- J/ApJS/165/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the catalog of 477 spectra from the Serendipitous Extragalactic X-ray Source Identification (SEXSI) program, a survey designed to probe the dominant contributors to the 2-10keV cosmic X-ray background. Our survey covers 1deg^2^ of sky to 2-10keV fluxes of 1x10^-14^ergs/cm^2^/s, and 2deg^2^ for fluxes of 3x10^-14^ergs/cm^2^/s. Our spectra reach to R-band magnitudes of ~<24 and have produced identifications and redshifts for 438 hard X-ray sources.
- ID:
- ivo://CDS.VizieR/J/ApJ/708/584
- Title:
- SEXSI Spitzer catalog
- Short Name:
- J/ApJ/708/584
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We compare the relative merits of active galactic nuclei (AGNs) selection at X-ray and mid-infrared wavelengths using data from moderately deep fields observed by both Chandra and Spitzer. The X-ray-selected AGN sample and associated photometric and spectroscopic optical follow-up are drawn from a subset of fields studied as part of the Serendipitous Extragalactic X-ray Source Identification (SEXSI) program. Mid-infrared data in these fields are derived from targeted and archival Spitzer imaging, and mid-infrared AGN selection is accomplished primarily through application of the Infrared Array Camera (IRAC) color-color AGN "wedge" selection technique. Nearly all X-ray sources in these fields which exhibit clear spectroscopic signatures of AGN activity have mid-infrared colors consistent with IRAC AGN selection. These are predominantly the most luminous X-ray sources. X-ray sources that lack high-ionization and/or broad lines in their optical spectra are far less likely to be selected as AGNs by mid-infrared color selection techniques. The fraction of X-ray sources identified as AGNs in the mid-infrared increases monotonically as the X-ray luminosity increases. Conversely, only 22% of mid-infrared-selected AGNs are detected at X-ray energies in the moderately deep (t_exp_~100ks) SEXSI Chandra data.
- ID:
- ivo://CDS.VizieR/J/ApJS/106/399
- Title:
- Seyfert 2 galaxies multiwavelength catalog
- Short Name:
- J/ApJS/106/399
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is a catalog of Seyfert 2 galaxies observed in the 2-10keV band (339 flux entries). In total, it contains data on 150 objects; for 76 objects, a positive detection is reported, while for the remaining sources, 2{sigma} upper limits to the X-ray emission are given. Most of the data have been collected from the literature over a period starting from 1974 up to the middle of 1995. Accurate searches of literature and databases were performed for all objects, and frequently spectral fits were reevaluated in order to make the data in the catalog uniform and complete. Some unpublished data are also included. For six objects, EXOSAT/ME data have been extracted from the satellite database and analyzed; the 13 fluxes obtained have been added to the present catalog. The compilation of hard X-ray data has been complemented with data in the soft (0.1-3keV) X-ray band, as well as in ultraviolet (1450A), optical (5500A), infrared (3.5, 12, 25, 60, 100mm), and radio (6cm) bands. Fluxes of the [O III] {lambda}5007 and H{beta} emission lines as well as the Balmer decrement H{alpha}/H{beta}, and axial ratio a/b are also given. The present database is meant to be a useful tool for the study of the Seyfert 2 phenomenon in its various aspects.
- ID:
- ivo://CDS.VizieR/J/ApJS/229/28
- Title:
- SFiNCs: X-ray, IR and membership catalogs
- Short Name:
- J/ApJS/229/28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Star Formation in Nearby Clouds (SFiNCs) project is aimed at providing a detailed study of the young stellar populations and of star cluster formation in the nearby 22 star-forming regions (SFRs) for comparison with our earlier MYStIX survey of richer, more distant clusters. As a foundation for the SFiNCs science studies, here, homogeneous data analyses of the Chandra X-ray and Spitzer mid-infrared archival SFiNCs data are described, and the resulting catalogs of over 15300 X-ray and over 1630000 mid-infrared point sources are presented. On the basis of their X-ray/infrared properties and spatial distributions, nearly 8500 point sources have been identified as probable young stellar members of the SFiNCs regions. Compared to the existing X-ray/mid-infrared publications, the SFiNCs member list increases the census of YSO members by 6%-200% for individual SFRs and by 40% for the merged sample of all 22 SFiNCs SFRs.
- ID:
- ivo://CDS.VizieR/J/ApJ/687/1230
- Title:
- SFXTs observed by Swift. I. Outside outbursts
- Short Name:
- J/ApJ/687/1230
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Supergiant fast X-ray transients (SFXTs) are a new class of high-mass X-ray binaries (HMXBs) discovered thanks to the monitoring of the Galactic plane performed with the INTEGRAL satellite in the last 5 years. To characterize the properties of these sources on timescales of months, we are performing a monitoring campaign with Swift of four SFXTs (IGR J16479-4514, XTE J1739-302, IGR J17544-2619, and AX J1841.0-0536/IGR J18410-0535). We report on the first 4 months of Swift observations, which started on 2007 October 26. We detect low-level X-ray activity in all four SFXTs, which demonstrates that these transient sources accrete matter even outside their outbursts. The X-ray spectra are typically hard, with an average 2-10keV luminosity during this monitoring of about 10^33^-10^34^erg/s. We detected pulsations from the pulsar AX J1841.0-0536/IGR J18410-0535, with a period of 4.7008+/-0.0004s.
- ID:
- ivo://CDS.VizieR/J/other/Sci/348.413
- Title:
- Sgr A East SNR multiwavelength images
- Short Name:
- J/other/Sci/348.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dust formation in supernova ejecta is currently the leading candidate to explain the large quantities of dust observed in the distant, early universe. However, it is unclear whether the ejecta-formed dust can survive the hot interior of the supernova remnant (SNR). We present infrared observations of ~0.02 solar masses of warm (~100 kelvin) dust seen near the center of the ~10,000-year-old Sagittarius A East SNR at the Galactic center. Our findings indicate the detection of dust within an older SNR that is expanding into a relatively dense surrounding medium (electron density ~10^3^ centimeters^-3^) and has survived the passage of the reverse shock. The results suggest that supernovae may be the dominant dust-production mechanism in the dense environment of galaxies of the early universe.