- ID:
- ivo://CDS.VizieR/J/ApJ/723/1119
- Title:
- Optical properties of radio galaxies at z<0.3
- Short Name:
- J/ApJ/723/1119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extended extragalactic radio sources have traditionally been classified into Fanaroff & Riley (FR) I and II types, based on the ratio r_s_ of the separation S between the brightest regions on either sides of the host galaxy and the total size T of the radio source (r_s_~S/T). In this paper, we examine the distribution of various physical properties as a function of r_s_ of 1040 luminous (L>~L*) extended radio galaxies (RGs) at z<0.3 selected with well-defined criteria from the SDSS (Strauss et al. 2002AJ....124.1810S), NVSS (Condon et al. 1998, Cat. VIII/65), and FIRST (Becker et al. 1995+, Cat. VIII/71) surveys. About 2/3 of the RGs are lobe dominated (LD) and 1/3 have prominent jets. If we follow the original definition of the FR types, i.e., a division based solely on r_s_, FRI and FRII RGs overlap in their host galaxy properties.
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- ID:
- ivo://CDS.VizieR/J/ApJ/840/97
- Title:
- Optical reverberation mapping campaign of 5 AGNs
- Short Name:
- J/ApJ/840/97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results from an optical reverberation mapping campaign executed in 2014 targeting the active galactic nuclei (AGNs) MCG+08-11-011, NGC 2617, NGC 4051, 3C 382, and Mrk 374. Our targets have diverse and interesting observational properties, including a "changing look" AGN and a broad-line radio galaxy. Based on continuum-H{beta} lags, we measure black hole masses for all five targets. We also obtain H{gamma} and HeII{lambda}4686 lags for all objects except 3C 382. The HeII{lambda}4686 lags indicate radial stratification of the BLR, and the masses derived from different emission lines are in general agreement. The relative responsivities of these lines are also in qualitative agreement with photoionization models. These spectra have extremely high signal-to-noise ratios (100-300 per pixel) and there are excellent prospects for obtaining velocity-resolved reverberation signatures.
- ID:
- ivo://CDS.VizieR/J/ApJS/145/199
- Title:
- Optical spectroscopic atlas of low-redshift AGN
- Short Name:
- J/ApJS/145/199
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectral atlas of the H{beta} region for 215 type 1 AGNs (luminous Seyfert 1/radio galaxy nuclei and low-z quasars) up to z~0.8. Line profiles and measures were derived from the database of intermediate resolution spectra (R>~1000) with average continuum level S/N ratio ~30. Parameters including rest frame equivalent width and FWHM are provided for the FeII_opt_ blend at {lambda}4570, H{beta}, HeII {lambda}4686, and the [OIII] {lambda}{lambda}4959, 5007 emission lines. We extract clean broad component H{beta} profiles and provide wavelength measurements at 0, 1/4, 1/2, 3/4, and 0.9 peak intensity levels in order to permit a quantitative definition of the H{beta} broad component for statistical studies. We also discuss sources of uncertainty, selection effects, and biases in our sample. The data are especially important for tests of the eigenvector 1 parameter space occupation and correlation. We show that the I Zw 1 template FeII_opt_ spectrum reproduces well the observed FeII_opt_ emission for a wide range of line width and strength. A detailed analysis of the data within the eigenvector 1 context is deferred to a companion paper.
- ID:
- ivo://CDS.VizieR/J/other/RMxAA/48.9
- Title:
- Optical spectroscopic atlas of MOJAVE AGNs
- Short Name:
- J/other/RMxAA/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an optical spectroscopic atlas for 123 core-dominated radio-loud active galactic nuclei with relativistic jets, drawn from the MOJAVE/2cm (Monitoring of Jets in AGN with VLBA Experiments) sample at 15GHz. It is the first time that spectroscopic and photometric parameters for a large sample of such type of AGN are presented.
- ID:
- ivo://CDS.VizieR/J/ApJS/191/124
- Title:
- Optical spectroscopy of ECDF-S X-ray sources
- Short Name:
- J/ApJS/191/124
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a program to acquire high-quality optical spectra of X-ray sources detected in the Extended-Chandra Deep Field-South (E-CDF-S) and its central 2Ms area. New spectroscopic redshifts, up to z=4, are measured for 283 counterparts to Chandra sources with deep exposures (t~2-9hr per pointing) using multi-slit facilities on both VLT (VIMOS) and Keck (DEIMOS), thus bringing the total number of spectroscopically identified X-ray sources to over 500 in this survey field. Since our new spectroscopic identifications are mainly associated with X-ray sources in the shallower 250ks coverage, we provide a comprehensive catalog of X-ray sources detected in the E-CDF-S including the optical and near-infrared counterparts, determined by a likelihood routine, and redshifts (both spectroscopic and photometric), that incorporate published spectroscopic catalogs, thus resulting in a final sample with a high fraction (80%) of X-ray sources having secure identifications. Our redshift catalog includes 17 type-2 QSOs at 1<~z<~3.5. Based on our deepest (9 hr) VLT/VIMOS observation, we identify "elusive" optically faint galaxies (Rmag~25) at z~2-3 based upon the detection of interstellar absorption lines (e.g., OII+SiIV, CII], CIV).
- ID:
- ivo://CDS.VizieR/J/A+AS/80/103
- Title:
- Optical spectroscopy of 1Jy, S4 and S5 sources
- Short Name:
- J/A+AS/80/103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/ApJ/748/49
- Title:
- Optical spectroscopy of 1LAC broad-line blazars
- Short Name:
- J/ApJ/748/49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on optical spectroscopy of 165 flat spectrum radio quasars (FSRQs) in the Fermi 1LAC sample, which have helped allow a nearly complete study of this population. Fermi FSRQs show significant evidence for non-thermal emission even in the optical; the degree depends on the {gamma}-ray hardness. They also have smaller virial estimates of hole mass than the optical quasar sample. This appears to be largely due to a preferred (axial) view of the {gamma}-ray FSRQ and non-isotropic (H/R ~ 0.4) distribution of broad-line velocities. Even after correction for this bias, the Fermi FSRQs show higher mean Eddington ratios than the optical population. A comparison of optical spectral properties with Owens Valley Radio Observatory radio flare activity shows no strong correlation.
- ID:
- ivo://CDS.VizieR/J/AJ/133/186
- Title:
- Optical spectroscopy of 77 luminous AGNs and QSOs
- Short Name:
- J/AJ/133/186
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical spectroscopy of a sample of 77 luminous active galactic nuclei (AGNs) and quasars selected on the basis of their mid-infrared colors. Our objects are selected from the Spitzer Extragalactic First Look Survey and the SWIRE XMM-Newton Large-Scale Structure Survey (XMM-LSS) fields, with a typical 24um flux density of 5mJy. The median redshift is 0.6, with a range of ~0.05-4. Only 33% (25 out of 77) of these objects are normal type 1 quasars, with no obscuration. Forty-four percent (34 out of 77) are type 2 objects, with high-ionization, narrow emission lines, and 14% (11 out of 77) are dust-reddened type 1 quasars, showing broad lines but a dust-reddened or unusually weak quasar continuum.
- ID:
- ivo://CDS.VizieR/III/175
- Title:
- Optical spectroscopy of radio sources
- Short Name:
- III/175
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A number of flat spectrum radio sources have been observed in optical spectroscopy; most of the sources are either classified as BL Lacertae objects or have been described as BL Lac candidates.
- ID:
- ivo://CDS.VizieR/J/ApJ/894/24
- Title:
- Optical variability of AGN from the HSC SSP survey
- Short Name:
- J/ApJ/894/24
- Date:
- 03 Dec 2021 00:44:13
- Publisher:
- CDS
- Description:
- We study variability of active galactic nuclei (AGNs) by using the deep optical multiband photometry data obtained from the Hyper Suprime-Cam Subaru Strategic Program (HSC SSP) survey in the COSMOS field. The images analyzed here were taken with 8, 10, 13, and 15 epochs over three years in the g, r, i, and z bands, respectively. We identified 491 robust variable AGN candidates, down to i=25mag and with redshift up to 4.26. Ninety percent of the variability-selected AGNs are individually identified with the X-ray sources detected in the Chandra COSMOS Legacy survey. We investigate their properties in variability by using structure function analysis and find that the structure function for low-luminosity AGNs (L_bol_<~10^45^erg/s) shows a positive correlation with luminosity, which is the opposite trend for the luminous quasars. This trend is likely to be caused by a larger contribution of the host galaxy light for lower-luminosity AGNs. Using the model templates of galaxy spectra, we evaluate the amount of host galaxy contribution to the structure function analysis and find that dominance of the young stellar population is needed to explain the observed luminosity dependence. This suggests that low-luminosity AGNs at 0.8<~z<~1.8 are predominantly hosted in star-forming galaxies. The X-ray stacking analysis reveals the significant emission from the individually X-ray undetected AGNs in our variability-selected sample. The stacked samples show very large hardness ratios in their stacked X-ray spectrum, which suggests that these optically variable sources have large soft X-ray absorption by dust-free gas.
