A5011238725- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Astrophysics and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Spectroscopy and Laser Applications
- Astro and Planetary Science
- Calibration and Measurement Techniques
- GNSS positioning and interference
- Pulsars and Gravitational Waves Research
- Geophysics and Gravity Measurements
- Scientific Research and Discoveries
- Advanced Measurement and Metrology Techniques
- Magnetic confinement fusion research
- Impact of Light on Environment and Health
- Seismic Imaging and Inversion Techniques
- Archaeology and Historical Studies
- X-ray Spectroscopy and Fluorescence Analysis
- Relativity and Gravitational Theory
- Nuclear physics research studies
United States Naval Research Laboratory
2014-2024
Naval Research Laboratory Remote Sensing Division
2022-2024
K Lab (United States)
2022
Bellingham Technical College
2018
National Radio Astronomy Observatory
2001-2012
Georgia State University
2011
University of America
2011
Catholic University of America
2011
Computational Physics (United States)
2010-2011
American Optometric Association
2006-2009
Active Galactic Nuclei (AGN) are axisymmetric systems to first order; their observed properties likely strong functions of inclination with respect our line sight. However, except for a few special cases, the specific inclinations individual AGN unknown. We have developed promising technique determining nearby by mapping kinematics narrow-line regions (NLRs), which often easily resolved Hubble Space Telescope (HST) [O III] imaging and long-slit spectra from Imaging Spectrograph (STIS). Our...
We present the study of relative angle between accretion disk (or radio jet) and galaxy for a sample Seyfert galaxies selected from mostly isotropic property, 60$\mu$m flux. For each we have pair points ($i$,$\delta$), which are inclination to line sight jet projected into plane sky host major axis, respectively. This data is combined with statistical technique determine distribution $\beta$ angles {\it in 3 dimensions}, axis. The analysis data, not differentiating 1's 2's, showed that...
We present a Hubble Space Telescope (HST) survey of extended [O III] emission for sample 60 Seyfert galaxies (22 1 and 38 2 galaxies), selected based on their far-infrared properties. The observations 42 these were done in snapshot with WFPC2. remaining 18 obtained from the HST archive, most which observed same configuration. These cover 68% objects defined by Kinney et al. create valuable data set study narrow-line region (NLR) properties galaxies. In this paper, we details observations,...
This paper represents a collective effort to provide an extensive electronic database useful for the interpretation of spectra and evolution galaxies. A broad variety empirical theoretical data are discussed here, made fully available in AAS CD-ROM Series, Vo. 7. Several stellar libraries part this database. They cover ultraviolet spectral range observed with IUE, optical from different ground-based telescopes, infrared data. Spectral type coverage depends on wavelength, but it is mostly...
We examine a representative sample of 35 Seyfert 2 nuclei. Previous work has shown that nearly half (15) these nuclei show the direct (but difficult to detect) spectroscopic signature at optical/near-UV wavelengths hot massive stars power circumnuclear starbursts. In present paper we variety more easily measured quantities for this sample, such as equivalent widths strong absorption features, continuum colors, emission line widths, ratios and profiles, far-IR luminosities, near-UV surface...
We present the results of a Hubble Space Telescope (HST) survey extended [OIII] emission in sample 60 nearby Seyfert galaxies (22 1's and 38 2's), selected by mostly isotropic properties. The comparison between semi major axis size their emitting regions (R_Maj) shows that 2's have similar distributions, which seems to contradict Unified Model predictions. discuss possible ways explain this result, could be due either observational limitations or models used for with our data. show 1 Narrow...
Previous ground-based observations of the Seyfert 2 galaxy Mrk 78 revealed a double set emission lines, similar to those seen in several active galactic nuclei (AGNs) from recent surveys. Are lines due two AGNs with different radial velocities same galaxy, or are they mass outflows single AGN? We present study outflowing ionized gas resolved narrow-line region (NLR) using Space Telescope Imaging Spectrograph (STIS) and Faint Object Camera aboard Hubble as part an ongoing project determine...
(Abridge): We present a spectroscopic study of the stellar populations Low Luminosity AGN (LLAGN). Our main goal is to determine whether stars who live in innermost (100 pc-scale) regions these galaxies are some way related emission line properties, which would imply link between population and ionization mechanism. High signal noise, ground based long-slit spectra 3500--5500 A interval were collected for 60 galaxies.Our findings are: (1) Few LLAGN have detectable young (< 10 Myr) starburst...
We present two-dimensional (2D) mapping of the gas velocity field inner few hundred parsecs six nearby active galaxies, using spectra obtained with integral unit Gemini Multi-Object Spectrograph instrument at North telescope. In our previous paper, we reported 2D stellar kinematics extracted from calcium triplet absorption lines. this use [S iii]λ9069 emission line to obtain flux distribution and in narrow-line region (NLR). The is extended by a its are dominated rotation galaxy plane....
Active galactic nuclei (AGN) can launch outflows of ionized gas that may influence galaxy evolution, and quantifying their full impact requires spatially resolved measurements the masses, velocities, radial extents. We previously reported these quantities for narrow-line region (NLR) in six low-redshift AGN, where velocities extents were determined from Hubble Space Telescope long-slit spectroscopy. However, calculating masses required multi-component photoionization models to account...
Abstract We present dynamical models of the narrow-line region (NLR) outflows in nearby Seyfert galaxies Mrk 3, 78, NGC 1068, and 4151 using observations from Hubble Space Telescope Apache Point Observatory. employ long-slit spectroscopy to map spatially resolved outflow rotational velocities ionized gas. also perform surface brightness decompositions host galaxy images constrain enclosed stellar mass distributions as functions distance supermassive black holes (SMBHs). Assuming that NLR gas...
We investigate the relation between characteristics of circumnuclear stellar population and both galaxy morphology presence close companions for a sample 35 Seyfert 2 nuclei. Fifteen galaxies present unambiguous signatures recent episodes star formation within ≈300 pc nucleus. When we relate this property to Hubble type host galaxy, find that incidence increases along sequence; it seems be greater than in non-Seyfert early types S0 Sa but similar later types. In early-type late-type...
We analyze the idea that nuclear activity, either active galactic nuclei (AGNs) or star formation, can be triggered by interactions studying percentage of active, H II, and quiescent galaxies with companions. Our sample was selected from Palomar survey avoids selection biases faced previous studies. This split into five different groups, Seyfert galaxies, LINERs, transition II absorption-line galaxies. The comparison between local galaxy density distributions groups showed in most cases...
We present two-dimensional maps of emission-line fluxes and kinematics, as well the stellar kinematics central few kpc five bright nearby Seyfert galaxies – Mrk 6, 79, 348, 607, 1058 obtained from observations with Gemini Multi-Object Spectrograph Integral Field Unit on North Telescope. The data cover inner 3.5 arcsec × 5.0 corresponding to physical scales in range 0.6 0.9–1.5 2.2 kpc2 at a spatial resolution ranging 110 280 pc spectral coverage 4300–7100 Å velocity ≈90 km s−1. gas...
Abstract We present a Hubble Space Telescope survey of extended [O iii ] λ 5007 emission for sample 12 nearby ( z < 0.12), luminous Type 2 quasars (QSO2s), which we use to measure the extent and kinematics their AGN-ionized gas. find that size observed regions scale with luminosity in comparison nearby, less Seyfert galaxies radially outflowing exist all targets. report an average maximum outflow radius ∼600 pc, gas continuing be kinematically influenced by central active galactic nucleus...
We present a series of statistical tests done to sample 29 Seyfert 1 and 59 2 galaxies selected from mostly isotropic properties, their far-infrared fluxes warm infrared colors. Such selection criteria provide profound advantage over the used by most investigators in past, such as ultraviolet excess. These were using ground-based high-resolution Very Large Array A-configuration 3.6 cm radio optical B I imaging data. From relative number 1's 2's, we calculate that torus half-opening angle is...
In a recently completed survey of the stellar population properties low-ionization nuclear emission-line regions (LINERs) and LINER/H ii transition objects (TOs), we have identified numerous class galactic nuclei which stand out because their conspicuous 108-9 yr populations, traced by high-order Balmer absorption lines other indices. These are called 'young-TOs', they all TO-like ratios. this paper extend previous work, concentrated on properties, investigating radial variations spectral in...
We present the results of VLA A-array 8.46 GHz continuum imaging 55 Seyfert galaxies (19 1's and 36 2's). These are part a larger sample 88 galaxies, selected from mostly isotropic properties, flux at 60 μm, warm infrared 25-60 μm colors. images used to study structure radio emission these their position angles, in case extended sources. data, combined with information broadband B I observations, have been orientation jets relative plane host (Kinney et al.).
We present a study of the stellar populations low-luminosity active galactic nuclei (LLAGNs). Our goal is to search for spectroscopic signatures young and intermediate-age stars investigate their relationship with ionization mechanism in LLAGNs. The method used based on population synthesis optical continuum innermost (20-100 pc) regions these galaxies. For this purpose, we have collected high spatial resolution (2900-5700 Å) STIS spectra 28 nearby LLAGNs that are available Hubble Space...
We present the results of an extensive literature search multiwavelength data for a sample 59 galaxies, consisting 26 Starbursts, 15 Seyfert 2's, 5 LINER's, 6 normal spirals and 7 elliptical galaxies. The include soft X-ray fluxes, ultraviolet optical spectra, near, mid/far infrared photometry radio measurements, selected to match as closely possible IUE aperture (10\arcsecx20\arcsec). galaxies are separated into groups with similar characteristics, namely, Ellipticals, Spirals, Starbursts...
We study the gas kinematics and chemical abundances in inner regions of six galaxies with active galactic nuclei. The were selected for having star-forming rings or spirals within a few kiloparsecs nucleus. goal project is to search any connections between gas-dynamics, abundances, nuclear activity. Narrowband images have been obtained map out ionized gas. Medium-dispersion long-slit spectroscopy at several positions over region has used obtain gaseous velocity field distribution excitation....
We present a spectroscopic atlas of active galactic nuclei covering the region around λλ8498, 8542, 8662 calcium triplet (CaT). The sample comprises 78 objects, divided into 43 Seyfert 2s, 26 1s, three starburst and six normal galaxies. spectra pertain to inner ∼300 pc in radius, thus central kinematics stellar populations data are used measure velocity dispersions (σ*) with both cross-correlation direct fitting methods. These measurements found be good agreement each other those previous...
We present an atlas of the central regions 75 Seyfert galaxies imaged in near-UV with Advanced Camera for Surveys Hubble Space Telescope at average resolution ∼10 pc. These data complement archival high-resolution from optical and near-IR wavelengths, creating extremely valuable set astronomers a broad range scientific interests. Our goal is to investigate nature light these objects, its relation circumnuclear starburst phenomenon, connection this evolution growth galaxy bulge black hole. In...
We present two-dimensional (2D) mapping of the stellar velocity field within inner 5 arcsec six nearby active galaxies, using spectra obtained with Integral Field Unit GMOS instrument at Gemini North telescope. The spatial resolution range from 20 to about 180 pc, and observed view covers a few hundred parsecs around nuclei. Calcium II triplet absorption features ~ 8500 A were used measure radial velocities dispersions (sigma). simple kinematical model assuming purely rotating system...
We present a study of the outflowing ionized gas in resolved narrow-line region (NLR) Seyfert 2 galaxy Mrk 573, and its interaction with an in- ner dust/gas disk, based on Hubble Space Telescope (HST) WFPC2 STIS observations. From spectroscopic imaging information, we determined fundamental geometry outflow inner via two modeling pro- grams used to recreate morphology these regions imaged HST. also that bicone ionizing radiation from Active Galactic Nucleus (AGN) intersects illuminating...