- ID:
- ivo://CDS.VizieR/J/ApJ/749/21
- Title:
- AGNs detected by 60 month Swift/BAT survey
- Short Name:
- J/ApJ/749/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Surveys above 10 keV represent one of the best resources to provide an unbiased census of the population of active galactic nuclei (AGNs). We present the results of 60 months of observation of the hard X-ray sky with Swift/Burst Alert Telescope (BAT). In this time frame, BAT-detected (in the 15-55keV band) 720 sources in an all-sky survey of which 428 are associated with AGNs, most of which are nearby. Our sample has negligible incompleteness and statistics a factor of ~2 larger over similarly complete sets of AGNs. Our sample contains (at least) 15 bona fide Compton-thick AGNs and 3 likely candidates. Compton-thick AGNs represent ~5% of AGN samples detected above 15keV. We use the BAT data set to refine the determination of the log N-log S of AGNs which is extremely important, now that NuSTAR prepares for launch, toward assessing the AGN contribution to the cosmic X-ray background. We show that the log N-log S of AGNs selected above 10 keV is now established to ~10% precision. We derive the luminosity function of Compton-thick AGNs and measure a space density of 7.9^+4.1^_-2.9_x10^-5^/Mpc3 for objects with a de-absorbed luminosity larger than 2x10^42^erg/s. As the BAT AGNs are all mostly local, they allow us to investigate the spatial distribution of AGNs in the nearby universe regardless of absorption. We find concentrations of AGNs that coincide spatially with the largest congregations of matter in the local (<=85Mpc) universe. There is some evidence that the fraction of Seyfert 2 objects is larger than average in the direction of these dense regions.
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- ID:
- ivo://CDS.VizieR/J/ApJS/221/12
- Title:
- AGNs in the MIR using AllWISE data
- Short Name:
- J/ApJS/221/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an all-sky sample of ~1.4 million active galactic nuclei (AGNs) meeting a two-color infrared photometric selection criteria for AGNs as applied to sources from the Wide-field Infrared Survey Explorer final catalog release (AllWISE). We assess the spatial distribution and optical properties of our sample and find that the results are consistent with expectations for AGNs. These sources have a mean density of ~38 AGNs per square degree on the sky, and their apparent magnitude distribution peaks at g~20, extending to objects as faint as g~26. We test the AGN selection criteria against a large sample of optically identified stars and determine the "leakage" (that is, the probability that a star detected in an optical survey will be misidentified as a quasi-stellar object (QSO) in our sample) rate to be <=4.0x10^-5^. We conclude that our sample contains almost no optically identified stars (<=0.041%), making this sample highly promising for future celestial reference frame work as it significantly increases the number of all-sky, compact extragalactic objects. We further compare our sample to catalogs of known AGNs/QSOs and find a completeness value of >~84% (that is, the probability of correctly identifying a known AGN/QSO is at least 84%) for AGNs brighter than a limiting magnitude of R<~19. Our sample includes approximately 1.1 million previously uncataloged AGNs.
- ID:
- ivo://CDS.VizieR/J/MNRAS/488/1035
- Title:
- AGN UV luminosity function
- Short Name:
- J/MNRAS/488/1035
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present lists of more than 80000 mostly UV-optical colour-selected AGN from 12 data sets, homogenised with respect to the assumed cosmology, magnitude system, and bandpass correction (if possible). We also present the selection functions for each of the 12 data sets, similarly homogenised. The total sample spans redshifts from z=0 to 7.5. The paper presents a detailed description of the combined sample and determinations of the AGN UV luminosity function throughout this redshift range. The code for developing and analysing AGN luminosity functions is available on GitHub (https://github.com/gkulkarni/QLF). The inferred UV luminosity functions can also be used to derive the contribution of AGN to the cosmic UV background and its effect on the intergalactic medium (IGM). The GitHub repository also includes code for this. Here we also present the luminosity functions in redshift bins, luminosity function evolution models from the paper, the 912{AA} and 1450{AA} volume emissivity of AGN from z=0 to 15, and the hydrogen photoionization rate contribution by AGN in this redshift range.
- ID:
- ivo://CDS.VizieR/J/A+AS/112/347
- Title:
- A Homogeneous Bright QSO Survey
- Short Name:
- J/A+AS/112/347
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the first paper in a series aimed at defining a statistically significant sample of QSOs in the range 15<B<18.75 and 0.3<z<2.2. The selection is carried out using direct plates obtained at the ESO and UK Schmidt Telescopes, scanned with the COSMOS facility and searched for objects with an ultraviolet excess. Follow-up spectroscopy, carried out at ESO La Silla, is used to classify each candidate. In this initial paper, we describe the scientific objectives of the survey; the selection and observing techniques used. We present the first sample of 285 QSOs (M_B_<-23) in a 153 sq.deg area, covered by the six "deep" fields, intended to obtain significant statistics down B=~18.75 with unprecedented photometric accuracy. From this database, QSO counts are determined in the magnitude range 17<B<18.75.
- ID:
- ivo://CDS.VizieR/II/298
- Title:
- AKARI/FIS All-Sky Survey Point Source Catalogues
- Short Name:
- II/298
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AKARI Infrared Astronomical Satellite observed the whole sky in the far infrared (50-180{mu}m) and the mid-infrared (9 and 18{mu}m) between May 2006 and August 2007 (Murakami et al. 2007PASJ...59S.369M) The AKARI/FIS All-Sky Survey Bright Source Catalog Version 1.0 provides positions and fluxes for 427071 point sources in the 4 far-infrared wavelengths centered at 65, 90, 140 and 160{mu}m (see filter characteristics in the "Note (1)" section below)
- ID:
- ivo://CDS.VizieR/II/297
- Title:
- AKARI/IRC mid-IR all-sky Survey
- Short Name:
- II/297
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AKARI Infrared Astronomical Satellite observed the whole sky in the far infrared (50-180{mu}m) and the mid-infrared (9 and 18{mu}m) between May 2006 and August 2007 (Murakami et al. 2007PASJ...59S.369M) The AKARI/IRC Point Source Catalogue Version 1.0 provides positions and fluxes for 870,973 sources observed with the InfraRed Camera (IRC): 844,649 sources in the S9W filter, and 194,551 sources in the L18W filter; the "Note (1)" section below provides a summary of the IRC filter characteristics.
- ID:
- ivo://CDS.VizieR/J/AJ/144/179
- Title:
- AKARI-LMC Point-source catalog
- Short Name:
- J/AJ/144/179
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a near- to mid-infrared point-source catalog of five photometric bands at 3.2, 7, 11, 15, and 24{mu}m for a 10deg^2^ area of the Large Magellanic Cloud (LMC) obtained with the Infrared Camera on board the AKARI satellite. To cover the survey area the observations were carried out at three separate seasons from 2006 May to June, 2006 October to December, and 2007 March to July. The 10{sigma} limiting magnitudes of the present survey are 17.9, 13.8, 12.4, 9.9, and 8.6mag at 3.2, 7, 11, 15, and 24{mu}m, respectively. The photometric accuracy is estimated to be about 0.1mag at 3.2{mu}m and 0.06-0.07 mag in the other bands. The position accuracy is 0.3" at 3.2, 7, and 11{mu}m and 1.0" at 15 and 24{mu}m. The sensitivities at 3.2, 7, and 24{mu}m are roughly comparable to those of the Spitzer SAGE LMC point-source catalog, while the AKARI catalog provides the data at 11 and 15 {mu}m, covering the mid-infrared spectral range contiguously. Two types of catalog are provided: a Catalog and an Archive. The Archive contains all the detected sources, while the Catalog only includes the sources that have a counterpart in the Spitzer SAGE point-source catalog. The Archive contains about 650,000, 140,000, 97,000, 43,000, and 52,000 sources at 3.2, 7, 11, 15, and 24{mu}m, respectively. Based on the catalog, we discuss the luminosity functions at each band, the color-color diagram, and the color-magnitude diagram using the 3.2, 7, and 11{mu}m band data. Stars without circumstellar envelopes, dusty C-rich and O-rich stars, young stellar objects, and background galaxies are located at distinct regions in the diagrams, suggesting that the present catalog is useful for the classification of objects toward the LMC.
48. AKARI N60
- ID:
- ivo://nasa.heasarc/skyview/akari
- Title:
- AKARI N60
- Short Name:
- AKARI
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The AKARI (formerly Astro-F) mission is a Japanese second generation all-sky infrared survey mission. SkyView currently includes surveys from the four bands of the FIS instrument: N60, WIDE-S, WIDE-L and N160. <p> These surveys cover 99% of the sky in four photometric bands centred at 65μm, 90μm, 140μm, and 160μm, with spatial resolutions ranging from 1-1.5'. <p> These data provide crucial information on the investigation and characterisation of the proper- ties of dusty material in the interstellar medium (ISM), since a significant portion of its energy is emitted between ∼50 and 200 μm. The large-scale distribution of interstellar clouds, their thermal dust temperatures, and their column densities can be investigated with the improved spatial resolution compared to earlier all-sky survey observations. In addition to the point source distribution, the large-scale distribution of ISM cirrus emis- sion, and its filamentary structure, are well traced. <p> Data are obtained using using the <a href="https://jvo.nao.ac.jp/index-e.html">JVO</a> AKARI Simple Image Access Service. Provenance: AKARI FIS map making team [Univ of Tokyo, ISAS/JAXA, Tohoku Univ, Tsukuba Univ, The Rutherford Appleton Laboratory, The Open Univ]. This is a service of NASA HEASARC.
- ID:
- ivo://CDS.VizieR/J/ApJS/214/20
- Title:
- AKARI NEP field J- and H- band source catalog
- Short Name:
- J/ApJS/214/20
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the J- and H-band source catalog covering the AKARI North Ecliptic Pole field. Filling the gap between the optical data from other follow-up observations and mid-infrared (MIR) data from AKARI, our near-infrared (NIR) data provides contiguous wavelength coverage from optical to MIR. For the J- and H-band imaging, we used the FLoridA Multi-object Imaging Near-ir Grism Observational Spectrometer on the Kitt Peak National Observatory 2.1m telescope covering a 5.1deg^2^ area down to a 5{sigma} depth of ~21.6mag and ~21.3mag (AB) for the J and H bands with an astrometric accuracy of 0.14" and 0.17" for 1{sigma} in R.A. and decl. directions, respectively. We detected 208020 sources for the J band and 203832 sources for the H band. This NIR data is being used for studies including the analysis of the physical properties of infrared sources such as stellar mass and photometric redshifts, and will be a valuable data set for various future missions.
- ID:
- ivo://CDS.VizieR/J/ApJS/183/295
- Title:
- A K-selected catalog of the ECDFS from MUSYC
- Short Name:
- J/ApJS/183/295
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new, K-selected, optical-to-near infrared photometric catalog of the Extended Chandra Deep Field South (ECDFS), making it publicly available to the astronomical community. The data set is founded on publicly available imaging, supplemented by original z'JK imaging data collected as part of the MUltiwavelength Survey by Yale-Chile (MUSYC). The final photometric catalog consists of photometry derived from UU_38_BVRIz'JK imaging covering the full 1/2x1/2{deg} of the ECDFS, plus H-band photometry for approximately 80% of the field. The 5{sigma} flux limit for point sources is K^(AB)^_tot_=22.0. This is also the nominal completeness and reliability limit of the catalog: the empirical completeness for 21.75<K<22.00 is >~85%. We have verified the quality of the catalog through both internal consistency checks, and comparisons to other existing and publicly available catalogs. As well as the photometric catalog, we also present catalogs of photometric redshifts and rest-frame photometry derived from the 10-band photometry. We have collected robust spectroscopic redshift determinations from published sources for 1966 galaxies in the catalog. Based on these sources, we have achieved a (1{sigma}) photometric redshift accuracy of {Delta}z/(1+z)=0.036, with an outlier fraction of 7.8%. Most of these outliers are X-ray sources. Finally, we describe and release a utility for interpolating rest-frame photometry from observed spectral energy distributions, dubbed InterRest available via http://www.strw.leidenuniv.nl/~ent/InterRest
