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Start Over Subject spectral energy distribution Publisher CDS
1. AGNs in submm-selected Lockman Hole galaxies
ID:
ivo://CDS.VizieR/J/A+A/514/A10
Title:
AGNs in submm-selected Lockman Hole galaxies
Short Name:
J/A+A/514/A10
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a comparison of the SCUBA half degree extragalactic survey (SHADES) at 450{mu}m, 850{mu}m and 1100{mu}m with deep guaranteed time 15{mu}m AKARI FU-HYU survey data and Spitzer guaranteed time data at 3.6-24{mu}m in the Lockman hole east. The AKARI data was analysed using bespoke software based in part on the drizzling and minimum-variance matched filtering developed for SHADES, and was cross-calibrated against ISO fluxes.
2. AGN torus models. SED library
ID:
ivo://CDS.VizieR/J/A+A/583/A120
Title:
AGN torus models. SED library
Short Name:
J/A+A/583/A120
Date:
21 Oct 2021
Publisher:
CDS
Description:
We assume that dust near active galactic nuclei (AGNs) is distributed in a torus-like geometry, which can be described as a clumpy medium or a homogeneous disk, or as a combination of the two (i.e. a two-phase medium). The dust particles considered are fluffy and have higher submillimeter emissivities than grains in the diffuse interstellar medium. The dust-photon interaction is treated in a fully self-consistent three-dimensional radiative transfer code. We provide an AGN library of spectral energy distributions (SEDs). Its purpose is to quickly obtain estimates of the basic parameters of the AGNs, such as the intrinsic luminosity of the central source, the viewing angle, the inner radius, the volume filling factor and optical depth of the clouds, and the optical depth of the disk midplane, and to predict the flux at yet unobserved wavelengths. The procedure is simple and consists of finding an element in the library that matches the observations. We discuss the general properties of the models and in particular the 10um silicate band. The AGN library accounts well for the observed scatter of the feature strengths and wavelengths of the peak emission. AGN extinction curves are discussed and we find that there is no direct one-to-one link between the observed extinction and the wavelength dependence of the dust cross sections. We show that objects in the library cover the observed range of mid-infrared colors of known AGNs. The validity of the approach is demonstrated by matching the SEDs of a number of representative objects: Four Seyferts and two quasars for which we present new Herschel photometry, two radio galaxies, and one hyperluminous infrared galaxy. Strikingly, for the five luminous objects we find that pure AGN models fit the SED without needing to postulate starburst activity.
3. Allsky cross-matched 3XMMe catalogue
ID:
ivo://CDS.VizieR/IX/48
Title:
Allsky cross-matched 3XMMe catalogue
Short Name:
IX/48
Date:
21 Oct 2021
Publisher:
CDS
Description:
ARCHES (Astronomical Resource Cross-matching for High Energy Studies) is a FP7-Space funded project whose aim is to provide the astronomical community with well-characterised multi-wavelength data in the form of spectral energy distributions (SEDs) for large samples of objects extracted from the 3XMM DR5 X-ray catalogue of serendipitous sources. The project has developed new tools implementing fully probabilistic simultaneous cross-correlation of several catalogues for unresolved sources. A cleaned and enhanced version of the 3XMM DR5 catalogue (the 3XMMe catalogue) has been cross-correlated using the ARCHES tool with a number of selected multi-wavelength archival catalogues. These catalogues cover wavelengths ranging from UV to far IR. They provide probabilities of associations, magnitude and fluxes from which spectral energy distributions can be extracted.
4. ALMA survey of Orion PGCCs (ALMASOP). II. 1.3mm
ID:
ivo://CDS.VizieR/J/ApJS/251/20
Title:
ALMA survey of Orion PGCCs (ALMASOP). II. 1.3mm
Short Name:
J/ApJS/251/20
Date:
21 Oct 2021
Publisher:
CDS
Description:
Planck Galactic Cold Clumps (PGCCs) are considered to be the ideal targets to probe the early phases of star formation. We have conducted a survey of 72 young dense cores inside PGCCs in the Orion complex with the Atacama Large Millimeter/submillimeter Array (ALMA) at 1.3mm (band 6) using three different configurations (resolutions ~0.35", 1.0", and 7.0") to statistically investigate their evolutionary stages and substructures. We have obtained images of the 1.3mm continuum and molecular line emission (^12^CO, and SiO) at an angular resolution of ~0.35" (~140au) with the combined arrays. We find 70 substructures within 48 detected dense cores with median dust mass ~0.093M_{sun}_ and deconvolved size ~0.27". Dense substructures are clearly detected within the central 1000au of four candidate prestellar cores. The sizes and masses of the substructures in continuum emission are found to be significantly reduced with protostellar evolution from Class 0 to Class I. We also study the evolutionary change in the outflow characteristics through the course of protostellar mass accretion. A total of 37 sources exhibit CO outflows, and 20 (>50%) show high-velocity jets in SiO. The CO velocity extents ({Delta}Vs) span from 4 to 110km/s with outflow cavity opening angle width at 400au ranging from [{Theta}_obs_]_400_~0.6"-3.9", which corresponds to 33.4{deg}-125.7{deg}. For the majority of the outflow sources, the {Delta}Vs show a positive correlation with [{Theta}_obs_]_400_, suggesting that as protostars undergo gravitational collapse, the cavity opening of a protostellar outflow widens and the protostars possibly generate more energetic outflows.
5. An atlas of UV-to-MIR galaxy SEDs
ID:
ivo://CDS.VizieR/J/ApJS/212/18
Title:
An atlas of UV-to-MIR galaxy SEDs
Short Name:
J/ApJS/212/18
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an atlas of 129 spectral energy distributions for nearby galaxies, with wavelength coverage spanning from the ultraviolet to the mid-infrared. Our atlas spans a broad range of galaxy types, including ellipticals, spirals, merging galaxies, blue compact dwarfs, and luminous infrared galaxies. We have combined ground-based optical drift-scan spectrophotometry with infrared spectroscopy from Spitzer and Akari with gaps in spectral coverage being filled using Multi-wavelength Analysis of Galaxy Physical Properties spectral energy distribution models. The spectroscopy and models were normalized, constrained, and verified with matched-aperture photometry measured from Swift, Galaxy Evolution Explorer, Sloan Digital Sky Survey, Two Micron All Sky Survey, Spitzer, and Wide-field Infrared Space Explorer images. The availability of 26 photometric bands allowed us to identify and mitigate systematic errors present in the data. Comparison of our spectral energy distributions with other template libraries and the observed colors of galaxies indicates that we have smaller systematic errors than existing atlases, while spanning a broader range of galaxy types. Relative to the prior literature, our atlas will provide improved K-corrections, photometric redshifts, and star-formation rate calibrations.
6. ASTRAL: reference spectra for evolved M stars
ID:
ivo://CDS.VizieR/J/ApJ/869/157
Title:
ASTRAL: reference spectra for evolved M stars
Short Name:
J/ApJ/869/157
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Hubble Space Telescope (HST) Treasury Program Advanced Spectral Library Project: Cool Stars was designed to collect representative, high-quality UV spectra of eight evolved F-M type cool stars. The Space Telescope Imaging Spectrograph (STIS) echelle spectra of these objects enable investigations of a broad range of topics, including stellar and interstellar astrophysics. This paper provides a guide to the spectra of the two evolved M stars, the M2 Iab supergiant {alpha}Ori and the M3.4 giant {gamma}Cru, with comparisons to the prototypical K1.5 giant {alpha}Boo. It includes identifications of the significant atomic and molecular emission and absorption features and discusses the character of the photospheric and chromospheric continua and line spectra. The fluorescent processes responsible for a large portion of the emission-line spectrum, the characteristics of the stellar winds, and the available diagnostics for hot and cool plasmas are also summarized. This analysis will facilitate the future study of the spectra, outer atmospheres, and winds, not only of these objects but of numerous other cool, low-gravity stars, for years to come.
7. BAT AGN spectroscopic survey. XI. IR photometry
ID:
ivo://CDS.VizieR/J/ApJ/870/31
Title:
BAT AGN spectroscopic survey. XI. IR photometry
Short Name:
J/ApJ/870/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
We quantify the luminosity contribution of active galactic nuclei (AGNs) to the 12{mu}m, mid-infrared (MIR; 5-38{mu}m), and total IR (5-1000{mu}m) emission in the local AGNs detected in the all-sky 70 month Swift/Burst Alert Telescope (BAT) ultrahard X-ray survey. We decompose the IR spectral energy distributions (SEDs) of 587 objects into the AGN and starburst components using templates for an AGN torus and a star-forming galaxy. This enables us to recover the emission from the AGN torus including the low-luminosity end, down to log(L_14-150_/erg/s)~41, which typically has significant host galaxy contamination. The sample demonstrates that the luminosity contribution of the AGN to the 12{mu}m, the MIR, and the total IR bands is an increasing function of the 14-150keV luminosity. We also find that for the most extreme cases, the IR pure-AGN emission from the torus can extend up to 90{mu}m. The total IR AGN luminosity obtained through the IR SED decomposition enables us to estimate the fraction of the sky obscured by dust, i.e., the dust covering factor. We demonstrate that the median dust covering factor is always smaller than the median X-ray obscuration fraction above an AGN bolometric luminosity of log(L_bol_^(AGN)^/erg/s)~42.5. Considering that the X-ray obscuration fraction is equivalent to the covering factor coming from both the dust and gas, this indicates that an additional neutral gas component, along with the dusty torus, is responsible for the absorption of X-ray emission.
8. Bolometric fluxes of eclipsing binaries in Tycho-2
ID:
ivo://CDS.VizieR/J/AJ/152/180
Title:
Bolometric fluxes of eclipsing binaries in Tycho-2
Short Name:
J/AJ/152/180
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present fits to the broadband photometric spectral energy distributions (SEDs) of 158 eclipsing binaries (EBs) in the Tycho-2 catalog. These EBs were selected because they have highly precise stellar radii, effective temperatures, and in many cases metallicities previously determined in the literature, and thus have bolometric luminosities that are typically good to <~10%. In most cases the available broadband photometry spans a wavelength range 0.4-10{mu}m, and in many cases spans 0.15-22{mu}m. The resulting SED fits, which have only extinction as a free parameter, provide a virtually model-independent measure of the bolometric flux at Earth. The SED fits are satisfactory for 156 of the EBs, for which we achieve typical precisions in the bolometric flux of {\simeq}3%. Combined with the accurately known bolometric luminosity, the result for each EB is a predicted parallax that is typically precise to <~5%. These predicted parallaxes-with typical uncertainties of 200{mu}as-are 4-5 times more precise than those determined by Hipparcos for 99 of the EBs in our sample, with which we find excellent agreement. There is no evidence among this sample for significant systematics in the Hipparcos parallaxes of the sort that notoriously afflicted the Pleiades measurement. The EBs are distributed over the entire sky, span more than 10mag in brightness, reach distances of more than 5kpc, and in many cases our predicted parallaxes should also be more precise than those expected from the Gaia first data release. The EBs studied here can thus serve as empirical, independent benchmarks for these upcoming fundamental parallax measurements.
9. CMB intensity map from WMAP and Planck PR2 data
ID:
ivo://CDS.VizieR/J/A+A/591/A50
Title:
CMB intensity map from WMAP and Planck PR2 data
Short Name:
J/A+A/591/A50
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe a new estimate of the cosmic microwave background (CMB) intensity map reconstructed by a joint analysis of the full Planck 2015 data (PR2) and nine years of WMAP data. The proposed map provides more than a mere update of the CMB map introduced in a previous paper since it benefits from an improvement of the component separation method L-GMCA (Local-Generalized Morphological Component Analysis), which facilitates efficient separation of correlated components. Based on the most recent CMB data, we further confirm previous results showing that the proposed CMB map estimate exhibits appealing characteristics for astrophysical and cosmological applications: i) it is a full-sky map as it did not require any inpainting or interpolation postprocessing, ii) foreground contamination is very low even on the galactic center, and iii) the map does not exhibit any detectable trace of thermal SZ contamination. We show that its power spectrum is in good agreement with the Planck PR2 official theoretical best-fit power spectrum. Finally, following the principle of reproducible research, we provide the codes to reproduce the L-GMCA, which makes it the only reproducible CMB map.
10. Composite SEDs of type 1 and type 2 QSOs
ID:
ivo://CDS.VizieR/J/ApJ/849/53
Title:
Composite SEDs of type 1 and type 2 QSOs
Short Name:
J/ApJ/849/53
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present observed mid-infrared and optical colors and composite spectral energy distributions (SEDs) of type 1 (broad-line) and 2 (narrow-line) quasars selected from Sloan Digital Sky Survey (SDSS) spectroscopy. A significant fraction of powerful quasars are obscured by dust and are difficult to detect in optical photometric or spectroscopic surveys. However, these may be more easily identified on the basis of mid-infrared (MIR) colors and SEDs. Using samples of SDSS type 1 and 2 matched in redshift and [OIII] luminosity, we produce composite rest-frame 0.2-15{mu}m SEDs based on SDSS, UKIDSS, and Wide-field Infrared Survey Explorer photometry and perform model fits using simple galaxy and quasar SED templates. The SEDs of type 1 and 2 quasars are remarkably similar, with the differences explained primarily by the extinction of the quasar component in the type 2 systems. For both types of quasar, the flux of the active galactic nucleus (AGN) relative to the host galaxy increases with AGN luminosity (L_[OIII]_) and redder observed MIR color, but we find only weak dependencies of the composite SEDs on mechanical jet power as determined through radio luminosity. We conclude that luminous quasars can be effectively selected using simple MIR color criteria similar to those identified previously (W1-W2>0.7; Vega), although these criteria miss many heavily obscured objects. Obscured quasars can be further identified based on optical-IR colors (for example, (u-W3[AB]>1.4(W1-W2[Vega])+3.2). These results illustrate the power of large statistical studies of obscured quasars selected on the basis of MIR and optical photometry.

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