- ID:
- ivo://CDS.VizieR/J/ApJ/695/276
- Title:
- Search for megamasers in type-2 AGNs
- Short Name:
- J/ApJ/695/276
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a search for H_2_O megamasers in 274 SDSS type-2 active galactic nuclei (AGNs; 0.3<z<0.83), half of which can be classified as type-2 quasi-stellar objects (QSOs) from their [OIII]5007 luminosity, using the Robert C. Byrd Green Bank Telescope (GBT) and the Effelsberg 100m radio telescope. Apart from the detection of the extremely luminous water vapor megamaser SDSS J080430.99+360718.1, already reported by Barvainis & Antonucci (2005ApJ...628...89B), we do not find any additional line emission. This high rate of nondetections is compared to the water maser luminosity function created from the 78 water maser galaxies known to date and its extrapolation toward the higher luminosities of "gigamasers" that we would have been able to detect given the sensitivity of our survey. The properties of the known water masers are summarized and discussed with respect to the nature of high-z type-2 AGNs and megamasers in general. In the Appendix (tables 4 and 5), we list 173 additional objects (mainly radio galaxies, but also QSOs and galaxies) that were observed with the GBT, the Effelsberg 100m radio telescope, or Arecibo Observatory without leading to the detection of water maser emission.
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Search Results
- ID:
- ivo://CDS.VizieR/VII/264
- Title:
- Second Byurakan Survey galaxies. Optical database
- Short Name:
- VII/264
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A database for the entire catalog of the Second Byurakan Survey (SBS) galaxies is presented. It contains new measurements of their optical parameters and additional information taken from the literature and other databases. The measurements were made using Ipg(near-infrared), Fpg(red) and Jpg(blue) band images from photographic sky survey plates obtained by the Palomar Schmidt telescope and extracted from the STScI Digital Sky Survey (DSS). The database provides accurate coordinates, morphological type, spectral and activity classes, apparent magnitudes and diameters, axial ratios, and position angles, as well as number counts of neighboring objects in a circle of radius 50kpc. The total number of individual SBS objects in the database is now 1676. The 188 Markarian galaxies which were re-discovered by SBS are not included in this database. We also include redshifts that are now available for 1576 SBS objects, as well as 2MASS infrared magnitudes for 1117 SBS galaxies.
- ID:
- ivo://CDS.VizieR/VII/276
- Title:
- Second Byurakan Survey. General Catalogue
- Short Name:
- VII/276
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Second Byurakan Survey (SBS) General Catalogue is presented. The SBS, a continuation of the Markarian survey reaching fainter limiting magnitudes, is the first survey which combines the search of galaxies and QSOs. A total area of 991 square degrees of the Northern sky was covered with the use of three objective prisms in combination with Schott filters. The limited magnitude on the best plates reached B~19.5. The General Catalogue consists of 3563 objects presented in two parts: a Catalogue of galaxies (1863 objects) and one of stellar objects (1700 objects). The Catalogue of SBS AGN consists of 761 objects (155 SyG, 596 QSOs, and 10 BLLac). Multi-wavelength data are presented for 1438 SBS objects identified with X-ray, IRAS and FIRST sources. Spectrophotometric observations obtained over 26 years are available for 3132 objects. Redshifts were measured for ~2100 extragalactic objects. Spectral classification is presented for ~2970 objects. The majority of the data is presented here for the first time. The Catalogue presents new large homogeneous deep representative complete samples of bright QSOs, AGNs, and faint UVX galaxies in the Northern sky. The SBS sample is found to be complete at 70% for galaxies and ~85% for AGN/QSOs with B<=17.5.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
