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3251. Second INTEGRAL AGN catalogue
ID:
ivo://CDS.VizieR/J/A+A/505/417
Title:
Second INTEGRAL AGN catalogue
Short Name:
J/A+A/505/417
Date:
21 Oct 2021
Publisher:
CDS
Description:
The INTEGRAL mission provides a large data set for studying the hard X-ray properties of AGN and allows testing the unified scheme for AGN. We present analysis of INTEGRAL IBIS/ISGRI, JEM-X, and OMC data for 199 AGN that have been reported to be detected by INTEGRAL above 20keV. The data analysed here allow a significant spectral extraction on 148 objects and optical variability study of 57 AGN. The slopes of the hard X-ray spectra of Seyfert 1 and Seyfert 2 galaxies are found to be consistent within the uncertainties, whereas lower luminosities are measured for the more absorbed/type 2 AGN. The intermediate Seyfert 1.5 objects exhibit hard X-ray spectra consistent with those of Seyfert 1. When applying a Compton reflection model, the underlying continua appear still the same in Seyfert 1 and 2 with photon index 2, and the reflection strength is about R=1, when assuming different inclination angles. A significant correlation is found between the hard X-ray and optical luminosity and the mass of the central black hole in the sense that the more luminous objects appear to be more massive. There is also a general trend for the absorbed sources and type 2 AGN to have lower Eddington ratios. The black hole mass appears to form a fundamental plane together with the optical and X-ray luminosity of the form LV being proportional to LX^0.6^.M^0.2^, similar to that found between radio luminosity LR, LX, and M. The unified model for Seyfert galaxies seems to hold, showing in hard X-rays that the central engine is the same in Seyfert 1 and 2 but seen under different inclination angles and absorption.
3252. Second Kiso Survey for UV-Excess Galaxies (KUG2)
ID:
ivo://CDS.VizieR/VII/261
Title:
Second Kiso Survey for UV-Excess Galaxies (KUG2)
Short Name:
VII/261
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have continued the surveys of ultraviolet-excess galaxies (abbreviated as KUGs) with the 105cm Kiso Schmidt telescope for two decades. The first survey was summarized in Takase and Miyauchi-Isobe (1993b), which lists 8,104 KUGs in 5,100 square degrees area. The second survey has been followed the first survey with a similar method, and lists 1,985 objects in 1,860 square degrees area in 6 papers (Miyauchi-Isobe and Maehara 1998-2006), supplementing the first survey. The second survey is completed with this lists, because the similar method (i.e. to use photographic plates) has become impossible at Kiso Schmidt telescope. There are some differences in photographic plates used and the observation condition in the surveys, such as emulsions, exposures or seeing sizes. Thus the homogeneity of the KUG survey is rather low, but its catalogue forms a somewhat large collection of UV-excess/blue galaxies. In these circumstances, we intend to merge both catalogues, upon requests from investigators working in follow-up observations of these galaxies. In the process of catalogue merging, we met a systematic difference between the first (KUG1) and the second (KUG2) surveys in overall properties of objects, such as brightness, degree of UV-excess and morphological type. This mainly originates from differences in the observation condition and personal errors in the survey. We scrutinize and discuss those differences and errors, and finally merge into a comprehensive catalogue of KUGs (KUG2000) in the machine-readable form including near ten thousand UV-excess galaxies.
3253. Second list of the Karachentsev catalog
ID:
ivo://CDS.VizieR/J/A+AS/147/187
Title:
Second list of the Karachentsev catalog
Short Name:
J/A+AS/147/187
Date:
21 Oct 2021
Publisher:
CDS
Description:
Table2 presents the results of HI observations of 78 'nearby dwarf galaxies' from Karachentseva et al. (1999A&AS..135..221K) obtained with the 100-m radio telescope at Effelsberg. This survey covers an area limited by R.A.[14h,23h30] and Dec[-20d,+60d] including the nearest cosmic void : R.A.[18h38m], Dec[+18d], V_0_<1500km/s.
3254. SED and age estimates of 104 M31 globular clusters
ID:
ivo://CDS.VizieR/J/AJ/139/1438
Title:
SED and age estimates of 104 M31 globular clusters
Short Name:
J/AJ/139/1438
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present photometry of 104 M31 globular clusters (GCs) and GC candidates in 15 intermediate-band filters of the Beijing-Arizona-Taiwan-Connecticut photometric system. The GCs and GC candidates were selected from the Revised Bologna Catalog (v.3.5). We obtain the cluster ages by comparing the photometric data with up-to-date theoretical synthesis models. The photometric data used are Galaxy Evolution Explorer far- and near-ultraviolet and Two Micron All Sky Survey near-infrared JHKs magnitudes, combined with optical photometry. The ages of our sample clusters cover a large range, although most clusters are younger than 10Gyr. Combined with the ages obtained in our series of previous papers focusing on the M31 GC system, we present the full M31 GC age distribution.
3255. SED fitting results of HETDEX pilot survey
ID:
ivo://CDS.VizieR/J/ApJ/786/59
Title:
SED fitting results of HETDEX pilot survey
Short Name:
J/ApJ/786/59
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use broadband photometry extending from the rest-frame UV to the near-IR to fit the individual spectral energy distributions of 63 bright (L(Ly{alpha})>10^43^ erg/s) Ly{alpha} emitting galaxies (LAEs) in the redshift range 1.9<z<3.6. We find that these LAEs are quite heterogeneous, with stellar masses that span over three orders of magnitude, from 7.5<log M/M_{sun}_<10.5. Moreover, although most LAEs have small amounts of extinction, some high-mass objects have stellar reddenings as large as E(B-V)~0.4. Interestingly, in dusty objects the optical depths for Ly{alpha} and the UV continuum are always similar, indicating that Ly{alpha} photons are not undergoing many scatters before escaping their galaxy. In contrast, the ratio of optical depths in low-reddening systems can vary widely, illustrating the diverse nature of the systems. Finally, we show that in the star-formation-rate-log-mass diagram, our LAEs fall above the "main-sequence" defined by z~3 continuum selected star-forming galaxies. In this respect, they are similar to submillimeter-selected galaxies, although most LAEs have much lower mass.
3256. SED of 113 dust-obscured galaxies at z~2
ID:
ivo://CDS.VizieR/J/AJ/143/125
Title:
SED of 113 dust-obscured galaxies at z~2
Short Name:
J/AJ/143/125
Date:
21 Oct 2021
Publisher:
CDS
Description:
Dust-obscured galaxies (DOGs) are a subset of high-redshift (z~2) optically-faint ultra-luminous infrared galaxies (ULIRGs, e.g., L_IR_>10^12^L_{sun}_). We present new far-infrared photometry, at 250, 350, and 500{mu}m (observed-frame), from the Herschel Space Telescope for a large sample of 113 DOGs with spectroscopically measured redshifts. Approximately 60% of the sample are detected in the far-IR. The Herschel photometry allows the first robust determinations of the total infrared luminosities of a large sample of DOGs, confirming their high IR luminosities, which range from 10^11.6^L_{sun}_<L_IR_(8-1000{mu}m)<10^13.6^L_{sun}_. 90% of the Herschel-detected DOGs in this sample are ULIRGs and 30% have L_IR_>10^13L{sun}. The rest-frame near-IR (1-3{mu}m) spectral energy distributions (SEDs) of the Herschel-detected DOGs are predictors of their SEDs at longer wavelengths.
3257. SED of K+A galaxies from UV to mid-IR
ID:
ivo://CDS.VizieR/J/MNRAS/431/2034
Title:
SED of K+A galaxies from UV to mid-IR
Short Name:
J/MNRAS/431/2034
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present spectrum synthesis fits to 808 K+A galaxies selected from the Sloan Digital Sky Survey (SDSS) and population synthesis of their spectral energy distributions, extending from the far-UV (0.15{mu}m) to the mid-IR (22{mu}m), based on the results of STARLIGHT code fitting to the SDSS spectra. Our modelling shows that K+A galaxies have undergone a large starburst, involving a median 50% of their present stellar masses, superposed over an older stellar population. The metal abundance of the intermediate-age stars shows that star formation did not take place in pristine gas, but was part of a dramatic increase in the star formation rates for originally gas-rich objects. We find no evidence for ongoing QSO activity in the UV, which is well modelled by the emission of intermediate-age stars. We use K+A galaxies as local counterparts of high-redshift objects to test for the presence of thermally pulsing asymptotic giant branch (TP-AGB) stars in similarly aged populations and find no excess in the infrared due to emission from such stars, arguing that more distant galaxies are indeed old and massive at their redshift. All of our galaxies show significant excesses in the mid-IR compared to the light from their stars. We fit this ad hoc with a 300K blackbody. Possible sources include TP-AGB stars, obscured young star clusters and hidden AGNs, heating a significant dust component.
3258. SED of Spitzer quasars (QUEST)
ID:
ivo://CDS.VizieR/J/ApJ/666/806
Title:
SED of Spitzer quasars (QUEST)
Short Name:
J/ApJ/666/806
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is the second paper studying the QSOs in the Spitzer QUEST sample. Previously we presented new PAH measurements and argued that most of the observed far-infrared (FIR) radiation is due to star-forming activity. Here we present spectral energy distributions (SEDs) by supplementing our data with optical, NIR, and FIR observations. We define two subgroups, of "weak FIR" and "strong FIR" QSOs, and a third group of FIR nondetections. Assuming a starburst origin for the FIR, we obtain "intrinsic" active galactic nucleus (AGN) SEDs by subtracting a starburst template from the mean SEDs. The resulting SEDs are remarkably similar for all groups.
3259. SED-selected AGN in the VIPERS field
ID:
ivo://CDS.VizieR/J/MNRAS/495/1853
Title:
SED-selected AGN in the VIPERS field
Short Name:
J/MNRAS/495/1853
Date:
21 Oct 2021
Publisher:
CDS
Description:
The detection of X-ray emission constitutes a reliable and efficient tool for the selection of active galactic nuclei (AGNs), although it may be biased against the most heavily absorbed AGNs. Simple mid-infrared (IR) broad-band selection criteria identify a large number of luminous and absorbed AGNs, yet again host contamination could lead to non-uniform and incomplete samples. Spectral energy distribution (SED) decomposition is able to decouple the emission from the AGN versus that from star-forming regions, revealing weaker AGN components. We aim to identify the obscured AGN population in the VIMOS Public Extragalactic Redshift Survey in the Canada-France-Hawaii Telescope Legacy Survey W1 field through SED modelling. We construct SEDs for 6860 sources and identify 160 AGNs at a high confidence level using a Bayesian approach. Using optical spectroscopy, we confirm the nature of ~85 per cent of the AGNs. Our AGN sample is highly complete (~92 per cent) compared to mid-IR colour-selected AGNs, including a significant number of galaxy-dominated systems with lower luminosities. In addition to the lack of X-ray emission (80 per cent), the SED fitting results suggest that the majority of the sources are obscured. We use a number of diagnostic criteria in the optical, IR, and X-ray regimes to verify these results. Interestingly, only 35 per cent of the most luminous mid-IR-selected AGNs have X-ray counterparts suggesting strong absorption. Our work emphasizes the importance of using SED decomposition techniques to select a population of type II AGNs, which may remain undetected by either X-ray or IR colour surveys.
3260. SEDs in ADFS (AKARI Deep Field South)
ID:
ivo://CDS.VizieR/J/A+A/514/A11
Title:
SEDs in ADFS (AKARI Deep Field South)
Short Name:
J/A+A/514/A11
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the nature and properties of far-infrared (FIR) sources in the AKARI Deep Field South (ADF-S). We performed an extensive search for the counterparts to 1000 ADF-S objects brighter than 0.0301Jy in the WIDE-S (90um) AKARI band in the public databases (NED and SIMBAD). We analyzed the properties of the resulting sample: statistics of the identified objects, quality of position determination of the ADF-S sources, their number counts, redshift distribution, and comparison of morphological types, when the corresponding information was available. We performed a simplified analysis of the clustering properties of the ADF-S sources and compiled spectral energy distributions (SEDs) of objects with the highest quality photometry, using three different models. Among 1000 investigated ADF-S sources, 545 were identified with sources at other wavelengths in public databases. From them, 518 are known galaxies and 343 of these were previously known as infra-red sources. Among the remaining sources, there are two quasars and both infrared and radio sources of unknown origin. Among six stellar identifications, at least five are probably the effect of contamination. We measured the redshifts of 48 extragalactic objects and determined the morphological types of 77 galaxies. We present SED models of 47 sources with sufficiently good photometric data. Conclusions: We conclude that the bright FIR point sources observed in the ADF-S are mostly nearby galaxies. Their properties are very similar to the properties of the local population of optically bright galaxies, except for unusually high ratio of peculiar or interacting objects and a lower percentage of elliptical galaxies. The percentage of lenticular galaxies is the same as in the optically bright population, which suggests that galaxies of this type may frequently contain a significant amount of cool dust. It is possible that source confusion plays a significant role in more than 34% of measurements. The SEDs correspond to a variety of galaxy types, from very actively star forming to very quiescent. The AKARI long wavelength bands data have enabled us to determine for the first time that these galaxies are objects with very cool dust.

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