- ID:
- ivo://CDS.VizieR/J/ApJ/772/131
- Title:
- Musket Ball Cluster redshift catalog
- Short Name:
- J/ApJ/772/131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Merging galaxy clusters have become one of the most important probes of dark matter, providing evidence for dark matter over modified gravity and even constraints on the dark matter self-interaction cross-section. To properly constrain the dark matter cross-section it is necessary to understand the dynamics of the merger, as the inferred cross-section is a function of both the velocity of the collision and the observed time since collision. While the best understanding of merging system dynamics comes from N-body simulations, these are computationally intensive and often explore only a limited volume of the merger phase space allowed by observed parameter uncertainty. Simple analytic models exist but the assumptions of these methods invalidate their results near the collision time, plus error propagation of the highly correlated merger parameters is unfeasible. To address these weaknesses I develop a Monte Carlo method to discern the properties of dissociative mergers and propagate the uncertainty of the measured cluster parameters in an accurate and Bayesian manner. I introduce this method, verify it against an existing hydrodynamic N-body simulation, and apply it to two known dissociative mergers: 1ES 0657-558 (Bullet Cluster) and DLSCL J0916.2+2951 (Musket Ball Cluster).
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- ID:
- ivo://CDS.VizieR/J/A+A/424/519
- Title:
- Naked active galactic nuclei
- Short Name:
- J/A+A/424/519
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we report the discovery of a new class of active galactic nucleus in which although the nucleus is viewed directly, no broad emission lines are present. The results are based on a survey for AGN in which a sample of about 800 quasars and emission line galaxies were monitored yearly for 25 years. Among the emission line galaxies was the expected population of Seyfert 2 galaxies with only narrow forbidden lines in emission, and no broad lines. However, from the long term monitoring programme it was clear that some 10% of these were strongly variable with strong continuum emission. It is argued that these objects can only be Seyfert 1 galaxies in which the nucleus is viewed directly, but in which broad emission lines are completely absent. We compare these observations with other cases from the literature where the broad line region is reported to be weak or variable, and investigate the possibility that the absence of the broad line component is due to reddening. We conclude that this does not account for the observations, and that in these AGN the broad line region is absent. We also tentatively identify more luminous quasars from our sample where the broad emission lines also appear to be absent. The consequences of this for AGN models are discussed, and a case is made that we are seeing AGN in a transition stage between the fuel supply from a surrounding star cluster being cut off, and the nucleus becoming dormant.
- ID:
- ivo://CDS.VizieR/J/ApJ/618/L83
- Title:
- Narrow iron K{alpha} lines in AGN
- Short Name:
- J/ApJ/618/L83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We assemble a sample consisting of 66 active galactic nuclei (AGNs) from the literature (Page et al., 2004MNRAS.347..316P) and from the XMM-Newton archive in order to investigate the origin of the 6.4keV narrow iron K{alpha} line (NIKAL). The X-ray Baldwin effect of the NIKAL is confirmed in this sample.
- ID:
- ivo://CDS.VizieR/J/ApJS/229/39
- Title:
- Narrow line Seyfert 1 galaxies from SDSS-DR12
- Short Name:
- J/ApJS/229/39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalog of narrow-line Seyfert 1 (NLSy1) galaxies from the Sloan Digital Sky Survey Data Release 12 (SDSS DR12). This was obtained by a systematic analysis through modeling of the continuum and emission lines of the spectra of all the 68859 SDSS-DR12 objects that are classified as "QSO" by the SDSS spectroscopic pipeline with z<0.8 and a median signal-to-noise ratio (S/N)>2/pixel. This catalog contains a total of 11101 objects, which is about 5 times larger than the previously known NLSy1 galaxies. Their monochromatic continuum luminosity at 5100{AA} is found to be strongly correlated with H{beta}, H{alpha}, and [OIII] emission line luminosities. The optical FeII strength in NLSy1 galaxies is about two times larger than the broad-line Seyfert 1 (BLSy1) galaxies. About 5% of the catalog sources are detected in the FIRST survey. The Eddington ratio ({xi}_Edd_) of NLSy1 galaxies has an average of log({xi}_Edd_) of -0.34, much higher than -1.03 found for BLSy1 galaxies. Their black hole masses (M_BH_) have an average of log(M_BH_) of 6.9M_{sun}_, which is less than BLSy1 galaxies, which have an average of log(M_BH_) of 8.0M_{sun}_. The M_BH_ of NLSy1 galaxies is found to be correlated with their host galaxy velocity dispersion. Our analysis suggests that geometrical effects playing an important role in defining NLSy1 galaxies and their M_BH_ deficit is perhaps due to their lower inclination compared to BLSy1 galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJS/166/128
- Title:
- Narrow line Seyfert 1 galaxies from SDSS-DR3
- Short Name:
- J/ApJS/166/128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out a systematic search for narrow line Seyfert 1 galaxies (NLS1s) from objects assigned as "QSOs" or "galaxies" in the spectroscopic sample of the Sloan Digital Sky Survey Data Release 3 (SDSS DR3) by a careful modeling of their emission lines and continua. The result is a uniform sample comprising ~2000 NLS1s. This sample dramatically increases the number of known NLS1s by a factor of ~10 over previous compilations. This paper presents the parameters of the prominent emission lines and continua, which were measured accurately with typical uncertainties <10%. Taking advantage of such an unprecedented large and uniform sample with accurately measured spectral parameters, we carried out various statistical analyses, some of which were only possible for the first time.
- ID:
- ivo://CDS.VizieR/J/AJ/131/1948
- Title:
- Narrow line Seyfert 1 galaxies in the FBQS
- Short Name:
- J/AJ/131/1948
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from the analysis of the optical spectra of 47 radio-selected narrow-line Seyfert 1 (NLS1) galaxies. These objects are a subset of the First Bright Quasar Survey (Cat. <J/AJ/112/407>) and were initially detected at 20cm (flux density limit 1Jy) in the VLA FIRST Survey.
- ID:
- ivo://CDS.VizieR/J/MNRAS/509/2377
- Title:
- Narrow-Line Seyfert 1 IR Survey
- Short Name:
- J/MNRAS/509/2377
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- We present a near-infrared spectroscopic survey of narrow-line Seyfert 1 galaxies in the southern hemisphere (using the SOFI instrument on the ESO-NTT telescope), sampled from optical surveys. We examine the kinematics of the broad-line region, probed by the emission line width of hydrogen (Paschen{alpha} and H{beta}). We observed 57 objects, of which we could firmly measure Paschen{alpha} in 49 cases. We find that a single Lorentzian fit (preferred on theoretical grounds) is preferred over multi-component Gaussian fits to the line profiles; a lack of narrow-line region emission, overwhelmed by the pole-on view of the broad line region (BLR) light, supports this. We recompute the catalog black hole (BH) mass estimates, using the values of FWHM and luminosity of H{beta}, both from catalog values and re-fitted Lorentzian values. We find a relationship slope greater than unity compared to the catalog values. We ascribe this to contamination by galactic light or difficulties with line flux measurements. However, the comparison of masses computed by the fitted Lorentzian and Gaussian measurements show a slope close to unity. Comparing the BH masses estimated from both Paschen{alpha} and H{beta}, the line widths and fluxes shows deviations from expected; in general, however, the computed BH masses are comparable. We posit a scenario where an intermixture of dusty and dust-free clouds (or alternately a structured atmosphere) differentially absorbs the line radiation of the BLR, due to dust absorption and hydrogen bound-free absorption.
- ID:
- ivo://CDS.VizieR/J/A+A/615/A13
- Title:
- Narrow line Seyfert 1 (NLS1) galaxies spectra
- Short Name:
- J/A+A/615/A13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Many active galactic nuclei (AGN) and particularly narrow line Seyfert 1 (NLS1) galaxies, usually exhibit blueshifts and blue wings in several emission lines, which are mainly associated to outflows and strong winds. Although there is no clear evidence of the physical origin of the [OIII] blue wings, it has been suggested that they could be emitted from the inner parts of the narrow line region (NLR). In order to study the radial velocity difference between the narrow component of H{beta} and the core component of [OIII]{lambda}5007 and the asymmetric emission of this forbidden line, we investigate a sample of NLS1 galaxies. One of the aims of this paper is to analyze the blue wings of the [OIII]{lambda}5007 profiles and their relation with the central engine. We have obtained and studied medium-resolution spectra (190km/s FWHM at H{beta}) of a sample of 28 NLS1 galaxies in the optical range 4300-5200{AA}. We performed Gaussian decomposition to the H{beta} and [OIII]{lambda}{lambda}4959,5007 emission profiles in order to study the distinct components of these lines. A new blue outlier galaxy is found, with the center of the core component of [OIII] blueshifted by 405km/s relative to the center of the narrow component of H{beta} line. We confirmed a previously known correlation between the blueshift and the FWHM of the core component of [OIII]{lambda}5007 line. We also corroborated the correlation between the latter and the velocity of the centroid of the blue wing. On the other hand, studying the radial velocity difference between the blue end of the asymmetric emission and the centroid of the core component of [OIII], we found a correlation between it and the central black hole mass and, therefore, with the luminosity of the broad component of H{beta}. Finally, we found a moderate correlation between the luminosity of the [OIII] blue wing and the black hole mass. These results suggest that the asymmetric emission of the [OIII] lines is related to the central engine, not only through the black hole but also in the intensity of the AGN, in agreement with previous results.
- ID:
- ivo://CDS.VizieR/J/ApJS/221/32
- Title:
- Narrow MgII absorption lines from SDSS-DR9Q
- Short Name:
- J/ApJS/221/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the Data Release 9 Quasar spectra from the Baryonic Oscillation Spectroscopic Survey, which does not include quasar spectra from the Sloan Digital Sky Survey Data Release 7, we detect narrow MgII{lambda}{lambda}2796,2803 absorption doublets in the spectral data redward of 1250{AA} (quasar rest frame) until the red wing of the MgII{lambda}2800 emission line. Our survey is limited to quasar spectra with a median signal-to-noise ratio <S/N>{>=}4/pixel in the surveyed spectral region, resulting in a sample that contains 43260 quasars. We have detected a total of 18598 MgII absorption doublets with 0.2933<=z_abs_<=2.6529. About 75% of absorbers have an equivalent width at rest frame of W_r_^{lambda}2796^. About 75% of absorbers have doublet ratios (DR=W_r_^{lambda}2796^/W_r_^{lambda}2803^) in the range of 1<=DR<=2, and about 3.2% lie outside the range of 1-{sigma}_DR_<=DR<=2+{sigma}_DR_. We characterize the detection false positives/negatives by the frequency of detected MgII absorption doublets in the limits of the S/N of the spectral data. The S/N=4.5 limit is assigned a completeness fraction of 53% and tends to be complete when the S/N is greater than 4.5. The redshift number densities of all of the detected MgII absorbers moderately increase from z~0.4 to z~1.5, which parallels the evolution of the cosmic star formation rate density. Limiting our investigation to those quasars whose emission redshift can be determined from narrow emission lines, the relative velocities ({beta}) of MgII absorbers have a complex distribution which probably consists of three classes of MgII absorbers: (1) cosmologically intervening absorbers; (2) environmental absorbers that reside within the quasar host galaxies or galaxy clusters; (3) quasar outflow absorbers. After subtracting contributions from cosmologically intervening absorbers and environmental absorbers, the {beta} distribution of the MgII might mainly be contributed by the quasar outflow absorbers and peaks at {upsilon}~1500km/s. This peak velocity is lower than the value of 2000km/s found in statistical analysis of CIV absorbers.
- ID:
- ivo://CDS.VizieR/J/A+A/433/497
- Title:
- Nearby early-type galaxies with ionized gas. I.
- Short Name:
- J/A+A/433/497
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- With the aim of building a data-set of spectral properties of well studied early-type galaxies showing emission lines, we present intermediate resolution spectra of 50 galaxies in the nearby Universe. The sample, which covers several of the E and S0 morphological sub-classes, is biased toward objects that might be expected to have ongoing and recent star formation, at least in small amounts, because of the presence of the emission lines. The emission is expected to come from the combination of active galactic nuclei and star formation regions within the galaxies. Sample galaxies are located in environments corresponding to a broad range of local galaxy densities, although predominantly in low density environments. Our long-slit spectra cover the 3700-7250{AA} wavelength range with a spectral resolution of approximately 7.6{AA} at 5550{AA}. The specific aim of this paper, and our first step in the investigation, is to map the underlying galaxy stellar population by measuring, along the slit positioned along the galaxy major axis, line-strength indices at several, homogeneous galacto-centric distances. For each object we extracted 7 luminosity-weighted apertures (with radii 1.5", 2.5", 10", r_e/10_, r_e/8_, r_e/4_ and r_e/2_) corrected for the galaxy ellipticity and 4 gradients (0<r<r_e/16_, r_e/16_<r<r_e/8_, r_e/8_<r<r_e/4_ and r_e/4_<r<r_e/2_). For each aperture and gradient we measured 25 line-strength indices: 21 of the set defined by the Lick-IDS ``standard'' system (Trager et al., 1998, Cat. J/ApJS/116/1) and 4 introduced by Worthey & Ottaviani (1997, Cat. J/ApJS/111/377). Line-strength indices have been transformed to the Lick-IDS system. Indices derived then include H{beta}, Mg_1_, Mg_2_, Mgb, MgFe, Fe5270, Fe5335 commonly used in classic index-index diagrams. The paper introduces the sample, presents the observations, describes the data reduction procedures, the extraction of apertures and gradients, the determination and correction of the line-strength indices, the procedure adopted to transform them into the Lick-IDS System and the procedures adopted for the emission correction. We finally discuss the comparisons between our dataset and line-strength indices available in the literature. A significant fraction, about 60%, of galaxies in the present sample has one previous measurement in the Lick-IDS system but basically restricted within the r_e/8_ region. Line-strength measures obtained both from apertures and gradients outside this area and within the r_e/8_ region, with the present radial mapping, are completely new.
