- ID:
- ivo://CDS.VizieR/J/ApJS/150/165
- Title:
- AGNs emission-line from Post-COSTAR
- Short Name:
- J/ApJS/150/165
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present consistent emission-line measurements for active galactic nuclei (AGNs), useful for reliable statistical studies of emission line properties. This paper joins a series including similar measurements of 993 spectra from the Large Bright Quasar Survey and 174 spectra of AGNs obtained from the Faint Object Spectrograph (FOS) on the Hubble Space Telescope (HST) prior to the installation of COSTAR. This time we concentrate on 220 spectra obtained with the FOS after the installation of COSTAR, completing the emission line analysis of all FOS archival spectra. We use the same automated technique as in previous papers, which accounts for Galactic extinction, models blended optical and UV iron emission, includes Galactic and intrinsic absorption lines, and models emission lines using multiple Gaussians. We present UV and optical emission line parameters (equivalent widths, fluxes, FWHM, and line positions) for a large number (28) of emission lines including upper limits for undetected lines. Further scientific analyses will be presented in subsequent papers.
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Search Results
122. AGNs in LSB galaxies
- ID:
- ivo://CDS.VizieR/J/other/RAA/9.269
- Title:
- AGNs in LSB galaxies
- Short Name:
- J/other/RAA/9.26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Active galactic nuclei (AGNs) in low surface brightness galaxies (LSBGs) have received little attention in previous studies. We present a detailed spectral analysis of 194 LSBGs from the Impey et al. (1996, Cat. J/ApJS/105/209) APM LSBG sample which has been observed spectroscopically by the Sloan Digital Sky Survey Data Release 5 (SDSS DR5). Our elaborate spectral analysis enables us to carry out, for the first time, reliable spectral classification of nuclear processes in LSBGs based on the standard emission line diagnostic diagrams in a rigorous way. Star-forming galaxies are common, as found in about 52% of LSBGs.We find that, contrary to some previous claims, the fraction of galaxies that contain AGNs is significantly lower than that found in nearby normal galaxies of high surface brightness. This is qualitatively in line with the finding of Impey et al. This result holds true even within each morphological type from Sa to Sc. LSBGs that have larger central stellar velocity dispersions or larger physical sizes tend to have a higher chance of harboring an AGN. For three AGNs with broad emission lines, the black hole masses estimated from the emission lines are broadly consistent with the well known M-{sigma}* relation established for normal galaxies and AGNs.
- ID:
- ivo://CDS.VizieR/J/ApJ/815/128
- Title:
- AGNs rest-frame UV and optical parameters
- Short Name:
- J/ApJ/815/128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ability to accurately derive black hole (BH) masses at progressively higher redshifts and over a wide range of continuum luminosities has become indispensable in the era of large-area extragalactic spectroscopic surveys. In this paper, we present an extension of existing comparisons between rest-frame UV and optical virial BH mass estimators to intermediate redshifts and luminosities comparable to the local H{beta} reverberation-mapped active galactic nuclei (AGNs). We focus on the Mg II, C IV, and C III] broad emission lines and compare them to both H{alpha} and H{beta}. We use newly acquired near-infrared spectra from the Fiber-fed Multi-object Spectrograph instrument on the Subaru telescope for 89 broad-lined AGNs at redshifts between 0.3 and 3.5, complemented by data from the AGES survey. We employ two different prescriptions for measuring the emission line widths and compare the results. We confirm that Mg II shows a tight correlation with H{alpha} and H{beta}, with a scatter of ~0.25 dex. The C IV and C III] estimators, while showing larger scatter, are viable virial mass estimators after accounting for a trend with the UV-to-optical luminosity ratio. We find an intrinsic scatter of ~0.37 dex between Balmer and carbon virial estimators by combining our data set with previous high redshift measurements. This updated comparison spans a total of three decades in BH mass. We calculate a virial factor for C IV/C III] logf_C IV/C III]_=0.87 with an estimated systematic uncertainty of ~0.4 dex and find excellent agreement between the local reverberation mapped AGN sample and our high-z sample.
- ID:
- ivo://CDS.VizieR/J/A+AS/135/437
- Title:
- AGNs with composite spectra. II.
- Short Name:
- J/A+AS/135/437
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled from the literature 88 emission-line galaxies for which the published line-ratios give indication of a "transition spectrum"; selected objects are located north of {delta}~-20{deg}, are brighter than B=17 and have z<0.1. We have observed 53 of these galaxies with the spectrograph CARELEC, attached to the OHP 1.93m telescope. The observations were carried out during several runs in May, June and July 1996 and January, March, October and November 1997. The journal of observations is given in Table 5. The spectra (R~1800) were analysed in terms of Gaussians to search for the presence of multiple line-components, coming from kinematically and spatially distinct regions - "composite spectra". The results of the fitting analysis are given in Table 6.
- ID:
- ivo://CDS.VizieR/J/ApJ/705/L76
- Title:
- AGNs with double-peaked [OIII] lines
- Short Name:
- J/ApJ/705/L76
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Double-peaked [OIII] profiles in active galactic nuclei (AGNs) may provide evidence for the existence of dual AGNs, but a good diagnostic for selecting them is currently lacking. Starting from ~7000 active galaxies in Sloan Digital Sky Survey DR7, we assemble a sample of 87 type 2 AGNs with double-peaked [OIII] profiles. The nuclear obscuration in the type 2 AGNs allows us to determine redshifts of host galaxies through stellar absorption lines. We typically find that one peak is redshifted and another is blueshifted relative to the host galaxy. We find a strong correlation between the ratios of the shifts and the double peak fluxes. The correlation can be naturally explained by the Keplerian relation predicted by models of co-rotating dual AGNs. The current sample statistically favors that most of the [OIII] double-peaked sources are dual AGNs and disfavors other explanations, such as rotating disk and outflows. These dual AGNs have a separation distance at ~1kpc scale, showing an intermediate phase of merging systems. The appearance of dual AGNs is about ~10^-2^, impacting on the current observational deficit of binary supermassive black holes with a probability of ~10^-4^ (Boroson & Lauer, 2009Natur.458...53B).
- ID:
- ivo://CDS.VizieR/J/A+A/357/839
- Title:
- AGN 2.5-11um spectroscopy
- Short Name:
- J/A+A/357/839
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations over the 2.5-11{mu}m range, with the ISOPHOT-S spectrometer and the ISOCAM imaging camera, of a sample of 57 AGNs and one non-active SB galaxy. The sample is about equally divided into type I (<=1.5; 28 sources) and type II (>1.5; 29 sources) objects.
- ID:
- ivo://CDS.VizieR/J/ApJ/772/26
- Title:
- AGN with WISE. II. The NDWFS Bootes field
- Short Name:
- J/ApJ/772/26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Stern et al. (2012ApJ...753...30S, Paper I) presented a study of Wide-field Infrared Survey Explorer (WISE) selection of active galactic nuclei (AGNs) in the 2deg^2^ COSMOS field, finding that a simple criterion W1-W2>=0.8 provides a highly reliable and complete AGN sample for W2<15.05, where the W1 and W2 passbands are centered at 3.4{mu}m and 4.6{mu}m, respectively. Here we extend this study using the larger 9deg^2^ NOAO Deep Wide-Field Survey Bootes field which also has considerably deeper WISE observations than the COSMOS field, and find that this simple color cut significantly loses reliability at fainter fluxes. We define a modified selection criterion combining the W1-W2 color and the W2 magnitude to provide highly reliable or highly complete AGN samples for fainter WISE sources. In particular, we define a color-magnitude cut that finds 130+/-4deg^-2^ AGN candidates for W2<17.11 with 90% reliability. Using the extensive UV through mid-IR broadband photometry available in this field, we study the spectral energy distributions of WISE AGN candidates. We find that, as expected, the WISE AGN selection can identify highly obscured AGNs, but that it is biased toward objects where the AGN dominates the bolometric luminosity output. We study the distribution of reddening in the AGN sample and discuss a formalism to account for sample incompleteness based on the step-wise maximum-likelihood method of Efstathiou et al. The resulting dust obscuration distributions depend strongly on AGN luminosity, consistent with the trend expected for a receding torus. At L_AGN_~3x10^44^erg/s, 29%+/-7% of AGNs are observed as Type 1, while at ~4x10^45^erg/s the fraction is 64%+/-13%. The distribution of obscuration values suggests that dust in the torus is present as both a diffuse medium and in optically thick clouds.
- ID:
- ivo://CDS.VizieR/J/A+A/523/A88
- Title:
- A Jupiter-mass companion around HD 109246
- Short Name:
- J/A+A/523/A88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the detection of a Jupiter-mass planet discovered with the SOPHIE spectrograph mounted on the 1.93-m telescope at the Haute-Provence Observatory. The new planet orbits HD 109246, a G0V star slightly more metallic than the Sun. HD 109246b has a minimum mass of 0.77M_{jup}_, an orbital period of 68 days, and an eccentricity of 0.12. It is placed in a sparsely populated region of the period distribution of extrasolar planets. We also present a correction method for the so-called seeing effect that affects the SOPHIE radial velocities. We complement this discovery announcement with a description of some calibrations that are implemented in the SOPHIE automatic reduction pipeline. These calibrations allow the derivation of the photon-noise radial velocity uncertainty and some useful stellar properties (vsini, [Fe/H], log R'hk) directly from the SOPHIE data.
- ID:
- ivo://CDS.VizieR/J/AJ/145/32
- Title:
- AKARI-LMC Near-infrared Spectroscopic Catalog
- Short Name:
- J/AJ/145/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We performed a near-infrared spectroscopic survey toward an area of ~10deg^2^ of the Large Magellanic Cloud (LMC) with the infrared satellite AKARI. Observations were carried out as part of the AKARI Large-area Survey of the Large Magellanic Cloud (LSLMC). The slitless multi-object spectroscopic capability of the AKARI/IRC enabled us to obtain low-resolution (R~20) spectra in 2-5{mu}m for a large number of point sources in the LMC. As a result of the survey, we extracted about 2000 infrared spectra of point sources. The data are organized as a near-infrared spectroscopic catalog. The catalog includes various infrared objects such as young stellar objects (YSOs), asymptotic giant branch (AGB) stars, supergiants, and so on. It is shown that 97% of the catalog sources have corresponding photometric data in the wavelength range from 1.2 to 11{mu}m, and 67% of the sources also have photometric data up to 24{mu}m. The catalog allows us to investigate near-infrared spectral features of sources by comparison with their infrared spectral energy distributions. In addition, it is estimated that about 10% of the catalog sources are observed at more than two different epochs. This enables us to study a spectroscopic variability of sources by using the present catalog. Initial results of source classifications for the LSLMC samples are presented. We classified 659 LSLMC spectra based on their near-infrared spectral features by visual inspection. As a result, it is shown that the present catalog includes 7 YSOs, 160 C-rich AGBs, 8 C-rich AGB candidates, 85 O-rich AGBs, 122 blue and yellow supergiants, 150 red super giants, and 128 unclassified sources. Distributions of the classified sources on the color-color and color-magnitude diagrams are discussed in the text. Continuous wavelength coverage and high spectroscopic sensitivity in 2-5{mu}m can only be achieved by space observations. This is an unprecedented large-scale spectroscopic survey toward the LMC in the near-infrared. A large number of near-infrared spectral data provided by the survey possess scientific potential that can be applied to various studies. In this paper, we present the details of the spectroscopic survey and the catalog, and discuss its scientific applications.
- ID:
- ivo://CDS.VizieR/J/PASJ/71/1
- Title:
- AKARI Near Infrared Asteroid Spectral Catalog V1
- Short Name:
- J/PASJ/71/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Knowledge of water in the solar system is important for the understanding of a wide range of evolutionary processes and the thermal history of the solar system. To explore the existence of water in the solar system, it is indispensable to investigate hydrated minerals and/or water ice on asteroids. These water-related materials show absorption features in the 3um band (wavelengths from 2.7 to 3.1um). We conducted a spectroscopic survey of asteroids in the 3um band using the Infrared Camera (IRC) on board the Japanese infrared satellite AKARI. In the warm mission period of AKARI, 147 pointed observations were performed for 66 asteroids in the grism mode for wavelengths from 2.5 to 5um. According to these observations, most C-complex asteroids have clear absorption features (>10% with respect to the continuum) related to hydrated minerals at a peak wavelength of approximately 2.75um, while S-complex asteroids have no significant features in this wavelength range. The present data are released to the public as the Asteroid Catalog using AKARI Spectroscopic Observations (AcuA-spec).
