A5004016676- Galaxies: Formation, Evolution, Phenomena
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Stellar, planetary, and galactic studies
- Astronomical Observations and Instrumentation
- Astrophysics and Cosmic Phenomena
- Astrophysics and Star Formation Studies
- Cosmology and Gravitation Theories
- Radio Astronomy Observations and Technology
- Black Holes and Theoretical Physics
- Plant Water Relations and Carbon Dynamics
- Relativity and Gravitational Theory
- Adaptive optics and wavefront sensing
- Computational Physics and Python Applications
- Advanced Mathematical Theories
- Color Science and Applications
- Advanced Optical Sensing Technologies
- Statistics Education and Methodologies
- Solar and Space Plasma Dynamics
- Particle physics theoretical and experimental studies
- Architecture and Art History Studies
- Advanced Statistical Methods and Models
- History and Theory of Mathematics
- Advanced Image Processing Techniques
Universidad Nacional Autónoma de México
2013-2025
Consejo Nacional de Humanidades, Ciencias y Tecnologías
2017-2022
National Institute of Astrophysics, Optics and Electronics
2013-2015
The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is first one for SDSS-V, fifth generation survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole (BHM), and Local Volume (LVM). This contains extensive targeting information two multi-object spectroscopy programs (MWM BHM), including input catalogs selection functions their numerous objectives. We describe production databases calibration- scientifically-focused...
[Abridged] We have been exploring a spectroscopic unification for all known types of broad line emitting AGN. The 4D Eigenvector 1 (4DE1) parameter space shows promise as capable organizing quasar diversity on sequence primarily governed by Eddington ratio. This paper considers the role CIV 1549 measures with special emphasis shift principal 4DE1 diagnostic. use HST archival spectra 130 sources S/N high enough to permit reliable component (BC) measures. find BC profile blueshift that is...
The last 25 years saw a major step forward in the analysis of optical and UV spectroscopic data large quasar samples. Multivariate statistical approaches have led to definition systematic trends observational properties that are basis physical dynamical modeling structure. We discuss empirical correlates so-called “main sequence” associated with Eigenvector 1, its governing parameters several implications on our view structure, as well some luminosity effects virialized component line...
We compare broad emission line profiles and estimate ratios for all major lines between Lyα Hβ in a sample of six quasars.The sources were chosen with two criteria mind: the existence high quality optical UV spectra as well possibility to spectroscopic diversity 4D Eigenvector 1 context (4DE1).In latter sense each source occupies region (bin) FWHM(Hβ) vs. Fe ii opt strength plane that is significantly different from others.High S/N are used templates modeling other (Lyα, Civλ1549, Heiiλ1640,...
Broad emission lines in quasars enable us to "resolve" structure and kinematics of the broad-line emitting region (BLR) thought involve an accretion disk feeding a supermassive black hole. Interpretation broad line measures within 4DE1 formalism simplifies apparent confusion among such data by contrasting unifying properties so-called high low accreting Population A B sources. Hβ serves as estimator hole mass, Eddington ratio source rest frame; latter being valuable input for Civλ1549...
The most highly accreting quasars (xA) are of special interest in studies the physics AGNs and host galaxy evolution. Quasars at high rates (L/LEdd $\sim$ 1) hold promise for use as 'standard candles': distance indicators detectable very redshift. However, their observational properties largely unknown. A large sample xA can clarify main radiating near L/LEdd 1 Hb spectral range redshift $\lt$ 0.8. We selection criteria derived from 4DE1 to identify analyze spectra a 334 candidate sources...
Abstract We present a comparative study of active galactic nuclei (AGN) between galaxy pairs and isolated galaxies with the final data release MaNGA integral field spectroscopic survey. build sample 391 kinematic within footprint survey select AGN using survey's spectra. use comoving volume densities samples to quantify effects that tidal interactions have on triggering nuclear accretion. Our hypothesis is pair contains are triggered by not only stochastic accretion but also tidally induced...
This review provides an observational perspective on the fundamental properties of super-Eddington accretion onto supermassive black holes in quasars. It begins by outlining selection criteria, particularly focusing optical and UV broad-line intensity ratios, used to identify a population unobscured candidates. Several defining features place these candidates at extreme end Population A main sequence quasars: among them are highest observed singly-ionized iron emission, outflow velocities...
This review provides an observational perspective on the fundamental properties of super-Eddington accretion onto supermassive black holes in quasars. It begins by outlining selection criteria, particularly focusing optical and UV broad-line intensity ratios, used to identify a population unobscured candidates. Several defining features place these candidates at extreme end Population A main sequence quasars: among them are highest observed singly-ionized iron emission, outflow velocities...
We describe a method for determination of physical conditions in the broad line regions significant subsample Seyfert-1 nuclei and quasars. Several diagnostic ratios based on intermediate (AlIII 1860, SiIII 1892) high (CIV 1549, SiIV 1397) ionization lines UV spectra quasars are used to constrain density, metallicity emitting gas. apply two extreme Population A - prototypical NLSy1 I Zw 1 high-z\ NLSy1-like object, SDSS J120144.36+011611.6. find well-defined conditions: low (ionization...
We present here the characterization of main properties a sample 98 AGN host galaxies, both type-II and type-I, in comparison with those about 2700 non-active galaxies observed by MaNGA survey. found that hosts are morphologically early-type or early-spirals. For given morphology are, average, more massive, compact, central peaked rather pressurethan rotational-supported systems. confirm previous results indicating located intermediate/transition region between star-forming non-star-forming...
[Abridged] Context: The advent of 8-10m class telescopes makes possible for the first time detailed comparison quasars with similar luminosity and very different redshifts. Aims: A search z-dependent gradients in line emission diagnostics derived physical properties by comparing, a narrow bolometric range (log L ~ 46.1 +/- 0.4 [\ergss]), some most luminous local (z < 0.6) lowest sources yet found at redshift z = 2.1 2.5. Method: Spectra 22 high were obtained 10.4m Gran Telescopio Canarias...
The inter-line comparison between high- and low-ionization emission lines has yielded a wealth of information on the quasar broad line region (BLR) structure dynamics, including perhaps earliest unambiguous evidence in favor disk + wind radio-quiet quasars. We carried out an analysis CIV 1549 Hbeta profiles 28 Hamburg-ESO high luminosity quasars 48 low-z, low sources order to test whether high-ionization width could be correlated with used as virial broadening estimator. analyze...
Following the established view of AGNs inner workings, an AGN is radio-loud (RL) if associated with relativistic ejections emitting a radio synchrotron spectrum (i.e., jetted AGN). If large samples optically-selected quasars are considered, identified as RL their Kellermann's loudness ratio RK > 10. Our aims to characterize optical properties different classes based on radio-loudness within quasar main sequence (MS) and test whether condition 10 sufficient for identification AGNs. A sample...
The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is first one for SDSS-V, fifth generation survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole (BHM), and Local Volume (LVM). This contains extensive targeting information two multi-object spectroscopy programs (MWM BHM), including input catalogs selection functions their numerous objectives. We describe production databases calibration- scientifically-focused...
Black Hole Mass (M_BH) estimation in quasars, especially at high redshift, involves use of single epoch spectra with s/n and resolution that permit accurate measurement the width a broad line assumed to be reliable virial estimator. Coupled an estimate radius region this yields M_BH. The (BLR) may inferred from extrapolation correlation between source luminosity reverberation derived r_BLR measures (the so-called Kaspi relation involving about 60 low z sources). We are exploring different...
ABSTRACT We present a study on the incidence of major mergers and their impact triggering nuclear activity in 47 type I 236 II optically selected AGN from MaNGA DR15 sample. From an estimate non-parametric image predictors (Gini, M20, concentration (C), asymmetry (A), clumpiness (S), Sérsic index (n), shape (AS)) using SDSS images, combination with Linear Discriminant Analysis Method, we identified merger stages. reinforced our results by looking for bright tidal features post-processed DESI...
Context:Quasars radiating at extreme Eddington ratios (xA) are likely a prime mover of galactic evolution and have been hailed as potential distance indicators. Their properties still scarcely known. Aims:We test the effectiveness selection criteria defined on 4D Eigenvector 1 (4DE1) for identifying xA sources. We provide quantitative description their UV spectra in redshift range 2<z<2.9. Methods:19 quasar candidates were identified using 4DE1 applied to SDSS spectra:...
Quasars accreting matter at very high rates (known as extreme Population A [xA] quasars, possibly associated with super-Eddington massive black holes) may provide a new class of distance indicators covering cosmic epochs from present day up to less than 1 Gyr the Big Bang. At more fundamental level, xA quasars are special interest in studies physics AGNs and host galaxy evolution. However, their observational properties largely unknown. can be identified relatively large numbers major...
Context. We present an analysis of UV spectra quasars at intermediate redshifts believed to belong the extreme Population A (xA), aimed estimate chemical abundances broad line emitting gas. follow approach described in a previous work, extending sample 42 sources. Aim. Our aim is test robustness carried out previously, as well confirm two most intriguing results this investigation: evidence very high solar metallicities and deviation relative abundance elements with respect values. Methods....
We present preliminary results of a spectroscopic analysis for sample type 1 highly accreting quasars (LLedd>0.2) at high redshift, z~2-3. The were observed with the OSIRIS spectrograph on GTC 10.4 m telescope located Observatorio del Roque de los Muchachos in La Palma. identified using 4D Eigenvector formalism, which is able to organize over broad range redshift and luminosity. kinematic physical properties line region have been derived by fitting profiles strong UV emission lines such as...
We present high signal-to-noise ratio UV spectra for eight quasars at z ∼ 3 obtained with Very Large Telescope/FORS. The enable us to analyze in detail the strong and weak emission features rest frame range 1300–2000 Å of each source (C iii] λ1909, Si λ1892, Al iii λ1860, ii λ1814, C iv λ1549 blended λ1397+O iv] λ1402). flux ratios λ1860/Si λ1549/Al λ1402/Si λ1892 λ1402/C strongly constrain ionizing photon metallicity through use diagnostic maps built from cloudy simulations. radius broad...
Abstract The identification of a virial broadening estimator in the quasar UV rest frame suitable for black hole mass computation at high redshift has become an important issue. We compare H i Balmer β line width to ones two intermediate-ionization lines: Al iii λ 1860 doublet and C iii] 1909 line, over wide interval luminosity (0 ≲ z 3.5; <?CDATA $43\lesssim \mathrm{log}L\lesssim 48.5$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>43</mml:mn>...
Context. The quasar class of extreme Population A (xA) (also known as super-Eddington accreting massive black holes, SEAMBHs) has been hailed potential distance indicators for cosmology. Aims. aim this paper is to define tight criteria their proper identification, starting from the main selection criterion R FeII > 1, and identify intruders that do not meet criteria, which nonetheless have selected xA because coarseness automatic searches. inclusion spurious sources may dramatically...