- ID:
- ivo://CDS.VizieR/J/A+A/603/A100
- Title:
- 37 GHz observations of NLS1 galaxies
- Short Name:
- J/A+A/603/A100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations performed at Metsahovi Radio Observatory at 37GHz are presented for a sample of 78 radio-loud and radio-quiet narrow-line Seyfert 1 (NLS1) galaxies, together with additional lower and higher frequency radio data from RATAN-600, Owens Valley Radio Observatory, and the Planck satellite. Most of the data have been gathered between February 2012 and April 2015 but for some sources even longer light curves exist. The detection rate at 37GHz is around 19%, which is comparable to other populations of active galactic nuclei presumed to be faint at radio frequencies, such as BL Lac objects. Variability and spectral indices are determined for sources with enough detections. Based on the radio data, many NLS1 galaxies show a blazar-like radio spectra exhibiting significant variability. The spectra at a given time are often inverted or convex. The source of the high-frequency radio emission in NLS1 galaxies, detected at 37GHz, is most probably a relativistic jet rather than star formation. Jets in NLS1 galaxies are therefore expected to be a much more common phenomenon than earlier assumed.
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- ID:
- ivo://CDS.VizieR/J/A+A/358/77
- Title:
- Hamburg/ESO survey for bright QSOs. III.
- Short Name:
- J/A+A/358/77
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Appendix to the above paper, containing the two large tables A.1 and B.1 described in the paper. Table A.1 gives the basic properties of the 207 survey fields used to construct the flux-limited sample, including field-dependent magnitude limits and adopted extinction values. Table B.1 lists the 415 QSOs and Seyfert 1 galaxies that form the sample, with positions, redshift and magnitudes, plus a cross-identification with the 1995 version of the AGN catalogue by Veron-Cetty & Veron (see Cat. <VII/215>).
- ID:
- ivo://CDS.VizieR/J/ApJ/702/1353
- Title:
- H{beta} and V-band light curves of NGC 4051
- Short Name:
- J/ApJ/702/1353
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results from a high sampling rate, multimonth reverberation mapping campaign undertaken primarily at MDM Observatory with supporting observations from telescopes around the world. The primary goal of this campaign was to obtain either new or improved H{beta} reverberation lag measurements for several relatively low luminosity active galactic nuclei (AGNs). We feature results for NGC 4051 here because, until now, this object has been a significant outlier from AGN scaling relationships, e.g., it was previously a ~2-3{sigma} outlier on the relationship between the broad-line region (BLR) radius and the optical continuum luminosity - the R_BLR_-L relationship. Our new measurements of the lag time between variations in the continuum and H{beta} emission line made from spectroscopic monitoring of NGC 4051 lead to a measured BLR radius of R_BLR_=1.87^+0.54^_-0.50_ light days and black hole mass of M_BH_=(1.73^+0.55^_-0.52_)x10^6^M_{sun}_. We also present a preliminary look at velocity-resolved H{beta} light curves and time delay measurements, although we are unable to reconstruct an unambiguous velocity-resolved reverberation signal.
- ID:
- ivo://CDS.VizieR/J/ApJS/105/93
- Title:
- H II Regions in Nearby Seyfert Galaxies
- Short Name:
- J/ApJS/105/93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Continuum-subtracted Halpha images of 17 nearby Seyfert galaxies are presented. The images are calibrated astrometrically using the Hubble Space Telescope Guide Star Catalog reference frame. For each galaxy, an inventory of H II regions detected using the COSMOS image classifier and centroider is provided. Salient features of each galaxy are described, including the distribution of the H II regions with reference to the galaxy morphology. Relevant abundance data from the literature are noted for each object. These images will find use as finding charts for follow-up spectrophotometric investigations of abundances, abundance gradients, and kinematics of H II regions in active galaxies, and for detailed studies of H II region populations in these objects.
- ID:
- ivo://CDS.VizieR/J/ApJS/101/287
- Title:
- H II Regions in Seyfert galaxies. I.
- Short Name:
- J/ApJS/101/287
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Data on positions, effective diameters, and absolute fluxes of H II regions on 21 Seyfert spiral galaxies are presented together with the H{alpha} + [N II] images and identification charts. The objects are selected from a larger emission-line survey of a distance-limited sample of southern Seyfert galaxies. Statistical analysis of the data as well as discussion and comparison of the H II region populations in Seyfert and normal galaxies will be presented in forthcoming papers.
- ID:
- ivo://CDS.VizieR/J/A+A/624/A42
- Title:
- H2O megamaser galaxies radio continuum 5GHz data
- Short Name:
- J/A+A/624/A42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An essential part of the paradigm describing active galactic nuclei is the alignment between the radio jet and the associated rotation axis of the sub-pc accretion disks. Because of the small linear and angular scales involved, this alignment has not yet been checked in a sufficient number of low luminosity active galactic nuclei (LLAGNs). The project examines the validity of this paradigm by measuring the radio continuum on the same physical scale as the accretion disks to investigate any possible connection between these disks and the radio continuum. We observed a sample of 18 LLAGNs in the 4.8GHz (6cm) radio continuum using the Very Long Baseline Array (VLBA) with 3.3-6.5ms resolution. The sources were selected to show both an edge-on accretion disk revealed by 22GHz H_2_O megamaser emission and signatures of a radio jet. Furthermore, the sources were previously detected in 33GHz radio continuum observations made with the Very Large Array. Five out of 18 galaxies observed were detected at 8{sigma} or higher levels (Mrk 0001, Mrk 1210, Mrk 1419, NGC 2273, and UGC 3193). While these five sources are known to have maser disks, four of them exhibit a maser disk with known orientation. For all four of these sources, the radio continuum is misaligned relative to the rotation axis of the maser disk, but with a 99.1% confidence level, the orientations are not random and are confined to a cone within 32{deg} of the maser disk's normal. Among the four sources the misalignment of the radio continuum with respect to the normal vector to the maser disk is smaller when the inner radius of the maser disk is larger. Furthermore, a correlation is observed between the 5GHz VLBA radio continuum and the [OIII] luminosity and also with the H_2_O maser disk's inner radius.
- ID:
- ivo://CDS.VizieR/J/ApJ/795/58
- Title:
- 1H 0323+342 rest frame optical spectrum with GHAO
- Short Name:
- J/ApJ/795/58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical and near-infrared (NIR) imaging data of the radio-loud, narrow-line Seyfert 1 galaxy 1H 0323+342, which shows intense and variable gamma-ray activity discovered by the Fermi satellite with the Large Area Telescope. Near-infrared and optical images are used to investigate the structural properties of the host galaxy of 1H 0323+342; this together with optical spectroscopy allows us to examine its black hole mass. Based on two-dimensional (2D) multiwavelength surface-brightness modeling, we find that statistically, the best model fit is a combination of a nuclear component and a Sersic profile (n~2.8). However, the presence of a disk component (with a small bulge n~1.2) also remains a possibility and cannot be ruled out with the present data. Although at first glance a spiral-arm-like structure is revealed in our images, a 2D Fourier analysis of the imagery suggests that this structure corresponds to an asymmetric ring, likely associated with a recent violent dynamical interaction. We discuss our results in the context of relativistic jet production and galaxy evolution.
- ID:
- ivo://CDS.VizieR/J/A+A/623/A82
- Title:
- HST/COS and FUSE UV spectra of Mrk 509
- Short Name:
- J/A+A/623/A82
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To elucidate the location, physical conditions, mass outflow rate, and kinetic luminosity of the outflow from the active nucleus of the Seyfert 1 galaxy Mrk 509 we used coordinated ultraviolet and X-ray spectral observations in 2012 to followup our lengthier campaign conducted in 2009. We observed Mrk 509 with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST) on 2012-09-03 and 2012-10-11 coordinated with X-ray observations using the High Energy Transmission Grating on the Chandra X-ray Observatory. Our far-ultraviolet spectra used grating G140L on COS to cover wavelengths from 920-2000{AA} at a resolving power of 2000, and gratings G130M and G160M to cover 1160-1750{AA} at a resolving power of 15000. We detect variability in the blue-shifted UV absorption lines on timescales spanning 3-12 years. The inferred densities in the absorbing gas are greater than logn[cm^-3^]~3. For ionization parameters ranging over logU=-1.5 to -0.2, we constrain the distances of the absorbers to be closer than 220pc to the active nucleus. The impact on the host galaxy appears to be confined to the nuclear region.
- ID:
- ivo://CDS.VizieR/J/A+A/319/33
- Title:
- Identification of X-ray sources around Seyferts
- Short Name:
- J/A+A/319/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Excess numbers of X-ray sources around bright Seyfert galaxies have been demonstrated with significances of association up to 7.4-sigma (Radecke, 1997A&A...319...18R). The optical identification of these sources is shown here to be predominantly blue stellar objects (BSO's) of which some are already catalogued as quasars. Excluding the two brightest Seyferts, a subset of 24 with apparent magnitudes between 8.04<=B_T_^o,i^<=12.90mag. show a minimum excess of >46 bright X-ray sources. These excess X-ray sources are generally distributed between 10'<r<40' and 12 of the Seyferts show conspicuous pairs of X-ray sources across their active nuclei. Additional pairing and alignment of sources is seen for the remaining Seyferts. Among the paired X-ray sources, 53 have been identified as BSO's. Some double and multiple BSO's have been identified which are candidates for groups and associations of quasars. Some groups are well aligned and some centered on small blue galaxies. Four previously known BL Lac objects fall close enough to the Seyferts in this sample to confirm, at a significance level of 1-2x10^-9^, a previously reported association of BL Lac objects with bright, low redshift galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJS/143/277
- Title:
- IRAS 1Jy sample of ultraluminous galaxies. I.
- Short Name:
- J/ApJS/143/277
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An imaging survey of the IRAS 1Jy sample of 118 ultraluminous infrared galaxies was conducted at optical (R) and near-infrared (K') wavelengths using the University of Hawaii 2.2 m telescope. The methods of observation and data reduction are described. An R and K' atlas of the entire sample is presented along with some of the basic astrometric and photometric parameters derived from these images. A more detailed analysis of these data is presented in a companion paper (Veilleux et al., 2002, Cat. <J/ApJS/143/315>).
