- ID:
- ivo://CDS.VizieR/J/AJ/111/696
- Title:
- Rotation curves of Seyfert galaxies with companions
- Short Name:
- J/AJ/111/696
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents imaging and optical spectroscopy of paired Seyfert galaxies and their companions. The aim is to seek common properties of Seyfert galaxies in interacting systems, which might provide evidence of AGN triggering in a way independent of the usual two-sample statistics which have proven ambiguous on this issue. Three kinds of comparison have been made -- the kinds of interactions involving Seyfert galaxies, the relative luminosities of the Seyferts and their companions, and the level of kinematic disturbance as measured from rotation curves. (1) Dynamics and tidal features have been used to determine (or at least limit) the sense of orbital motion (direct/ retrograde/polar with respect to the Seyfert galaxy's disk) for many of these pairs. There is no obviously preferred kind of interaction -- direct, polar, and retrograde encounters are all well represented, despite the gross differences in dynamical response of a disk to these various kinds of encounter. To the extent that triggering of Seyfert nuclei occurs due to tidal encounters, the existence of a perturbation seems more important than its exact duration or detailed effects on the disk. However, the ratio of merging to paired Seyferts is higher than for disk galaxies in general, consistent with more effective triggering of AGN in this specific phase; the implied time scale for enhanced occurrence during mergers is the same as the timescape for merger remnants to appear as such, a few disk-edge crossing times (typically several times 10^8yr). (2) Seyfert nuclei occur preferentially in the brighter members of galaxy pairs, by a median of 0.93mag after making the maximal correction for contaminating nonstellar light in the nuclei. Only about 1/3 of this effect can be accounted for by the known tendency of Seyfert nuclei to occur in more luminous galaxies. Enhancement of AGN by interactions is evidently more effective for more luminous galaxies (though this will also be the case if both star formation and AGN occurrence are enhanced in the same galaxies). (3) The rotation curves of the paired Seyferts show systematically small regions of rising or solid-body rotation compared to the disk radius, as a group comparable to Sa but very different from Sb or Sc galaxies (even for Seyfert galaxies with Hubble type later than Sa). There is weak evidence that this difference is also present with respect to more isolated Seyfert galaxies. Despite the obvious utility of a dynamically disturbed disk for transport of angular momentum and "feeding the monster," Seyfert galaxies in pairs actually have smaller kinematic disturbances (measured by the maximum departure from a symmetric rotation curve, normalized to the full rotation amplitude) than found in a complete sample of non-Seyfert spirals in pairs.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/574/A121
- Title:
- RXJ2314.9+2243 from radio to X-rays
- Short Name:
- J/A+A/574/A121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Radio-loud narrow-line type 1 galaxies provide us with a fresh look at the blazar phenomenon, the causes of radio loudness, and the physics of jet formation. We present a multi-wavelength study of the radio-loud narrow-line type 1 quasar RX J2314.9+2243, which exhibits some remarkable multi-wavelength properties. It is among the few radio-loud narrow-line type 1 galaxies, with a tentative {gamma}-ray detection, is luminous in the infrared, and shows an exceptionally broad and blueshifted [OIII]{lambda}5007 emission-line component. In order to understand the nature of this source, we have obtained optical, UV, X-ray, and radio observations of RX J2314.9+2243.
- ID:
- ivo://CDS.VizieR/J/ApJ/782/45
- Title:
- SEAMBHs. I. Mrk 142, Mrk 335, and IRAS F12397+3333
- Short Name:
- J/ApJ/782/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report first results from a large project to measure black hole (BH) mass in high accretion rate active galactic nuclei (AGNs). Such objects may be different from other AGNs in being powered by slim accretion disks and showing saturated accretion luminosities, but both are not yet fully understood. The results are part of a large reverberation mapping (RM) campaign using the 2.4m Shangri-La telescope at the Yunnan Observatory in China. The goals are to investigate the gas distribution near the BH and the properties of the central accretion disks, to measure BH mass and Eddington ratios, and to test the feasibility of using such objects as a new type of cosmological candles. The paper presents results for three objects, Mrk 335, Mrk 142, and IRAS F12397+3333, with H{beta} time lags relative to the 5100{AA} continuum of 10.6_-2.9_^+1.7^, 6.4_-2.2_^+0.8^ and 11.4_-1.9_^+2.9^ days, respectively. The corresponding BH masses are (8.3_-3.2_^+2.6^)x10^6^M_{sun}_, (3.4_-1.2_^+0.5^)x10^6^M_{sun}_, and (7.5_-4.1_^+4.3^x10^6^M_{sun}_, and the lower limits on the Eddington ratios are 0.6, 2.3, and 4.6 for the minimal radiative efficiency of 0.038. Mrk 142 and IRAS F12397+333 (extinction corrected) clearly deviate from the currently known relation between H{beta} lag and continuum luminosity. The three Eddington ratios are beyond the values expected in thin accretion disks and two of them are the largest measured so far among objects with RM-based BH masses. We briefly discuss implications for slim disks, BH growth, and cosmology.
- ID:
- ivo://CDS.VizieR/J/ApJS/253/20
- Title:
- SEAMBHs XII. Reberberation mapping for 15 PG QSOs
- Short Name:
- J/ApJS/253/20
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we present the first results of the long-term high-cadence spectroscopic monitoring of 15 PG quasars with relatively strong FeII emission, as a part of a broader reverberation mapping campaign performed using the Calar Alto Observatory's 2.2m telescope. The V-band, 5100{AA} continuum, and H{beta} broad emission line light curves are measured for a set of quasars for periods ranging from dozens to more than a hundred epochs between 2017 May and 2020 July. Accurate time lags between the variations of the H{beta} broad-line fluxes and the optical continuum strength are obtained for all 15 quasars, ranging from 17.0_-3.2_^+2.5^ to 95.9_-23.9_^+7.1^ days in the rest frame. The virial masses of the central supermassive black holes are derived for all 15 quasars, ranging between 0.50_-0.19_^+0.18^ and 19.17_-2.73_^+2.98^ in units of 10^7^M_{sun}_. For 11 of the objects in our sample, this is the first reverberation analysis to be published. Of the rest, two objects have been the subject of previous reverberation studies, but we determine time lags for these that are only half as long as those found in the earlier investigations, which had only been able to sample much more sparsely. The remaining two objects have previously been monitored with high sampling rates. Our results here are consistent with the earlier findings, in the sense that the time lag and the line width vary inversely, consistent with virialization.
- ID:
- ivo://CDS.VizieR/J/ApJ/877/23
- Title:
- SEAMBHs. X. Reverberation mapping campaign compilation
- Short Name:
- J/ApJ/877/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We compiled a sample of 73 active galactic nuclei (AGNs) with reverberation mapping (RM) observations from RM campaigns, including our ongoing campaign of monitoring super-Eddington accreting massive black holes (BHs). This sample covers a large range of BH mass (M_{bullet}_=10^6^-9^M_{sun}_), dimensionless accretion rates (dM/dt=10^-2.7^-10^2.7^), and 5100{AA} luminosity (L_5100_=10^42-46^erg/s), allowing us to systematically study the AGN variability and their relations with BH mass, accretion rates, and optical luminosity. We employed the damped random walk (DRW) model to delineate the optical variability of continuum at 5100{AA} and obtained damped variability timescale ({tau}_d_) and amplitude ({sigma}_d_) using a Markov Chain Monte Carlo method. We also estimated the traditional variability amplitudes (F_var_), which provide a model-independent measure and therefore are used to test the DRW results. We found that AGN variability characteristics are generally correlated with (M_{bullet}_, dM/dt, L_5100_). These correlations are smooth from sub-Eddington to super-Eddington accretion AGNs, probably implying that the AGN variability may be caused by the same physical mechanism.
- 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.
- 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/J/ApJ/705/14
- Title:
- Seyfert galaxies in the mid-IR
- Short Name:
- J/ApJ/705/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An analysis of archival mid-infrared (mid-IR) spectra of Seyfert galaxies from the Spitzer Space Telescope observations is presented. We characterize the nature of the mid-IR active nuclear continuum by subtracting a template starburst spectrum from the Seyfert spectra. The long wavelength part of the spectrum contains a strong contribution from the starburst-heated cool dust; this is used to effectively separate starburst-dominated Seyferts from those dominated by the active nuclear continuum. Within the latter category, the strength of the active nuclear continuum drops rapidly beyond ~20um. On average, type 2 Seyferts have weaker short-wavelength active nuclear continua as compared to type 1 Seyferts. Type 2 Seyferts can be divided into two types, those with strong polycyclic aromatic hydrocarbon (PAH) bands and those without.
- ID:
- ivo://CDS.VizieR/J/ApJ/788/159
- Title:
- 17 Seyfert 1 galaxies light curves
- Short Name:
- J/ApJ/788/159
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a dust reverberation survey for 17 nearby Seyfert 1 galaxies, which provides the largest homogeneous data collection for the radius of the innermost dust torus. A delayed response of the K-band light curve after the V-band light curve was found for all targets, and 49 measurements of lag times between the flux variation of the dust emission in the K band and that of the optical continuum emission in the V band were obtained by the cross-correlation function analysis and also by an alternative method for estimating the maximum likelihood lag. The lag times strongly correlated with the optical luminosity in the luminosity range of M_V_=-16 to -22 mag, and the regression analysis was performed to obtain the correlation log {Delta}t (days)=-2.11 -0.2 M_V_ assuming {Delta}t{prop.to}L^0.5^, which was theoretically expected. We discuss the possible origins of the intrinsic scatter of the dust lag-luminosity correlation, which was estimated to be approximately 0.13 dex, and we find that the difference of internal extinction and delayed response of changes in lag times to the flux variations could have partly contributed to intrinsic scatter. However, we could not detect any systematic change of the correlation with the subclass of the Seyfert type or the Eddington ratio. Finally, we compare the dust reverberation radius with the near-infrared interferometric radius of the dust torus and the reverberation radius of broad Balmer emission lines. The interferometric radius in the K band was found to be systematically larger than the dust reverberation radius in the same band by the about a factor of two, which could be interpreted by the difference between the flux-weighted radius and response-weighted radius of the innermost dust torus. The reverberation radius of the broad Balmer emission lines was found to be systematically smaller than the dust reverberation radius by about a factor of four to five, which strongly supports the unified scheme of the Seyfert type of active galactic nuclei (AGNs). Moreover, we examined the radius-luminosity correlations for the hard X-ray (14-195 keV) and the [O IV] {lambda}25.89 {mu}m emission-line luminosities, which would be applicable for obscured AGNs.
- 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.
