- ID:
- ivo://CDS.VizieR/J/ApJS/250/10
- Title:
- SDSS-RM AGNs CFHT & Bok photometry over 4yrs
- Short Name:
- J/ApJS/250/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Sloan Digital Sky Survey (SDSS) Reverberation Mapping program monitors 849 active galactic nuclei (AGNs) both spectroscopically and photometrically. The photometric observations used in this work span over 4yr and provide an excellent baseline for variability studies of these objects. We present the photometric light curves from 2014 to 2017 obtained by the Steward Observatory's Bok telescope and the Canada-France-Hawaii telescope with MegaCam. We provide details on the data acquisition and processing of the data from each telescope, the difference imaging photometry used to produce the light curves, and the calculation of a variability index to quantify each AGN's variability. We find that the Welch-Stetson J index provides a useful characterization of AGN variability and can be used to select AGNs for further study.
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742. SDSS-ROSAT AGN data
- ID:
- ivo://CDS.VizieR/J/AJ/130/387
- Title:
- SDSS-ROSAT AGN data
- Short Name:
- J/AJ/130/387
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using a sample of 228 optically selected active galactic nuclei (AGNs) in the 0.01-6.3 redshift range with a high fraction of X-ray detections (81%-86%), we study the relation between rest-frame UV and soft X-ray emission and its evolution with cosmic time. The majority of the AGNs in our sample (155 objects) have been selected from the Sloan Digital Sky Survey (SDSS) in an unbiased way, rendering the sample results representative of all SDSS AGNs.
- ID:
- ivo://CDS.VizieR/J/ApJ/716/866
- Title:
- SDSS search for binary AGN
- Short Name:
- J/ApJ/716/866
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present active galactic nuclei (AGNs) from the Sloan Digital Sky Survey (SDSS) having double-peaked profiles of [OIII]5007,4959 and other narrow emission lines, motivated by the prospect of finding candidate binary AGNs. These objects were identified by means of a visual examination of 21592 quasars at z<0.7 in SDSS Data Release 7 (DR7). Of the spectra with adequate signal-to-noise, 148 spectra exhibit a double-peaked [OIII] profile. Of these, 86 are Type 1 AGNs and 62 are Type 2 AGNs. Only two give the appearance of possibly being optically resolved double AGNs in the SDSS images, but many show close companions or signs of recent interaction. Radio-detected quasars are three times more likely to exhibit a double-peaked [OIII] profile than quasars with no detected radio flux, suggesting a role for jet interactions in producing the double-peaked profiles. Of the 66 broad-line (Type 1) AGNs that are undetected in the FIRST survey, 0.9% show double-peaked [OIII] profiles.
- ID:
- ivo://CDS.VizieR/J/ApJ/850/140
- Title:
- SDSS spectral analysis of IR-bright DOGs
- Short Name:
- J/ApJ/850/140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the ionized gas properties of infrared (IR)-bright dust-obscured galaxies (DOGs) that show an extreme optical/IR color, (i-[22])_AB_>7.0, selected with the Sloan Digital Sky Survey (SDSS) and Wide-field Infrared Survey Explorer (WISE). For 36 IR-bright DOGs that show [OIII]{lambda}5007 emission in the SDSS spectra, we performed a detailed spectral analysis to investigate their ionized gas properties. In particular, we measured the velocity offset (the velocity with respect to the systemic velocity measured from the stellar absorption lines) and the velocity dispersion of the [OIII] line. We found that the derived velocity offset and dispersion of most IR-bright DOGs are larger than those of Seyfert 2 galaxies (Sy2s) at z<0.3, meaning that the IR-bright DOGs show relatively strong outflows compared to Sy2s. This can be explained by the difference in IR luminosity contributed from active galactic nuclei, L_IR_ (AGN), because we found that (i) L_IR_ (AGN) correlates with the velocity offset and dispersion of [OIII] and (ii) our IR-bright DOG sample has larger L_IR_ (AGN) than Sy2s. Nevertheless, the fact that about 75% IR- bright DOGs have a large (>300km/s) velocity dispersion, which is a larger fraction compared to other AGN populations, suggests that IR-bright DOGs are good laboratories to investigate AGN feedback. The velocity offset and dispersion of [OIII] and [NeIII]{lambda}3869 are larger than those of [OII]{lambda}3727, which indicates that the highly ionized gas tends to show stronger outflows.
- ID:
- ivo://CDS.VizieR/J/ApJ/758/1
- Title:
- SDSS-Spitzer AGN properties
- Short Name:
- J/ApJ/758/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study a combined sample of 264 star-forming, 51 composite, and 73 active galaxies using optical spectra from the Sloan Digital Sky Survey (SDSS) and mid-infrared (mid-IR) spectra from the Spitzer Infrared Spectrograph. We examine optical and mid-IR spectroscopic diagnostics that probe the amount of star formation and relative energetic contributions from star formation and an active galactic nucleus (AGN). Overall we find good agreement between optical and mid-IR diagnostics. Misclassifications of galaxies based on the SDSS spectra are rare despite the presence of dust obscuration. The luminosity of the [Ne II] 12.8{mu}m emission line is well correlated with the star formation rate measured from the SDSS spectra, and this holds for the star-forming, composite, and AGN-dominated systems. AGNs show a clear excess of [Ne III] 15.6{mu}m emission relative to star-forming and composite systems. We find good qualitative agreement between various parameters that probe the relative contributions of the AGN and star formation, including the mid-IR spectral slope, the ratio of the [Ne V] 14.3{mu}m to [Ne II] 12.8{mu}m fluxes, the equivalent widths of the 7.7{mu}m, 11.3{mu}m, and 17{mu}m polycyclic aromatic hydrocarbon (PAH) features, and the optical "D" parameter which measures the distance at which a source lies from the locus of star-forming galaxies in the optical BPT emission-line diagnostic diagram. We also consider the behavior of the three individual PAH features by examining how their flux ratios depend upon the degree of AGN dominance. We find that the PAH 11.3{mu}m feature is significantly suppressed in the most AGN-dominated systems.
- ID:
- ivo://CDS.VizieR/J/MNRAS/455/2551
- Title:
- SDSS/3XMM X-ray-selected LINERs
- Short Name:
- J/MNRAS/455/2551
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A sample of 576 X-ray-selected LINERs was constructed by combining data from the 3XMM-DR4 and SDSS-DR7 catalogues. The sample was used to investigate the fraction of galaxies hosting a LINER, finding that the fraction is a strong function of both stellar mass and black hole mass (increasing as f_LINER_{prop.to}M*^1.6+/-0.2^ and f_LINER_{propto}M_BH_^0.6+/-0.1^, respectively) and that it rises close to unity at the highest black hole masses and lowest X-ray luminosities. After obtaining radio flux densities from the FIRST survey, the sample was also used to investigate the Fundamental Plane of black hole activity - a scale-invariant relationship between black hole mass, X-ray luminosity and radio luminosity that is believed to hold across at least nine orders of magnitude of mass. There are key advantages in using only LINERs for the derivation as these are the counterparts of the 'low-hard' X-ray binaries for which the relationship is tightest. The Fundamental Plane was found to be log(L_R_/(erg/s)) = 0.65(+/-0.07)log(L_X_/(10^42^erg/s)) + 0.69(+/-0.10)log(M_BH_/10^8^M_{sun}_) + 38.35(+/-0.10). The scatter around the plane was 0.73+/-0.03dex, too large to suggest that the Fundamental Plane can be used as a tool to estimate black hole mass from the observables of X-ray and radio luminosity. The black hole mass scaling is sensitive to the slope of the mass - velocity dispersion relation and, in order to achieve consistency with X-ray binaries, the analysis favours a steep gradient for this relationship, as found in recent research.
- ID:
- ivo://CDS.VizieR/J/ApJ/793/108
- Title:
- SEAMBHs. II. Continuum and Hbeta LCs
- Short Name:
- J/ApJ/793/108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the second in a series of papers reporting on a large reverberation mapping (RM) campaign to measure black hole (BH) mass in high accretion rate active galactic nuclei (AGNs). The goal is to identify super-Eddington accreting massive black holes (SEAMBHs) and to use their unique properties to construct a new method for measuring cosmological distances. Based on theoretical models, the saturated bolometric luminosity of such sources is proportional to the BH mass, which can be used to obtain their distance. Here we report on five new RM measurements and show that in four of the cases, we can measure the BH mass and three of these sources are SEAMBHs. Together with the three sources from our earlier work, we now have six new sources of this type. We use a novel method based on a minimal radiation efficiency to identify nine additional SEAMBHs from earlier RM-based mass measurements. We use a Bayesian analysis to determine the parameters of the new distance expression and the method uncertainties from the observed properties of the objects in the sample. The ratio of the newly measured distances to the standard cosmological ones has a mean scatter of 0.14 dex, indicating that SEAMBHs can be use as cosmological distance probes. With their high luminosity, long period of activity, and large numbers at high redshifts, SEAMBHs have a potential to extend the cosmic distance ladder beyond the range now explored by Type Ia supernovae.
- 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/ApJ/806/22
- Title:
- SEAMBHs IV. H{beta} time lags
- Short Name:
- J/ApJ/806/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have completed two years of photometric and spectroscopic monitoring of a large number of active galactic nuclei (AGNs) with very high accretion rates. In this paper, we report on the result of the second phase of the campaign, during 2013-2014, and the measurements of five new H{beta} time lags out of eight monitored AGNs. All five objects were identified as super-Eddington accreting massive black holes (SEAMBHs). The highest measured accretion rates for the objects in this campaign are dM/dt>~200, where dM/dt=dM/dt_{dot}_/L_Edd_C^-2^, dM/dt_{dot}_ is the mass accretion rates, L_Edd_ is the Eddington luminosity and c is the speed of light.
- ID:
- ivo://CDS.VizieR/J/ApJ/856/6
- Title:
- SEAMBHs IX. 10 new H{beta} light curves
- Short Name:
- J/ApJ/856/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As one paper in a series reporting on a large reverberation mapping campaign of super-Eddington accreting massive black holes (SEAMBHs) in active galactic nuclei (AGNs), we present the results of 10 SEAMBHs monitored spectroscopically during 2015-2017. Six of them are observed for the first time, and have generally higher 5100{AA} luminosities than the SEAMBHs monitored in our campaign from 2012 to 2015; the remaining four are repeat observations to check if their previous lags change. Similar to the previous SEAMBHs, the H{beta} time lags of the newly observed objects are shorter than the values predicted by the canonical RH{beta}-L5100 relation of sub-Eddington AGNs, by factors of ~2-6, depending on the accretion rate. The four previously observed objects have lags consistent with previous measurements. We provide linear regressions for the RH{beta}-L5100 relation, solely for the SEAMBH sample and for low-accretion AGNs. We find that the relative strength of Fe ii and the profile of the H{beta} emission line can be used as proxies of accretion rate, showing that the shortening of H{beta} lags depends on accretion rates. The recent SDSS-RM discovery of shortened H{beta} lags in AGNs with low accretion rates provides compelling evidence for retrograde accretion onto the black hole. These evidences show that the canonical RH{beta}-L5100 relation holds only in AGNs with moderate accretion rates. At low accretion rates, it should be revised to include the effects of black hole spin, whereas the accretion rate itself becomes a key factor in the regime of high accretion rates.
