165 citations · 1.3k across the 24 of their papers we have counts for
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A Spitzer Spectroscopic Survey of Low Ionization Nuclear Emission-line Regions: Characterization of the Central Source
R. P. Dudik, S. Satyapal, D. Marcu
We have conducted a comprehensive mid-IR spectroscopic investigation of 67 Low Ionization Nuclear Emission Line Regions (LINERs) using archival observations from the high resolutio…
Spitzer Uncovers Active Galactic Nuclei Missed by Optical Surveys in 7 Late-type Galaxies
S. Satyapal, D. Vega, R. P. Dudik +2
We report the discovery using Spitzers high resolution spectrograph of 7 Active Galactic Nuclei (AGN) in a sample of 32 late-type galaxies that show no definitive signatures of AGN…
The Discovery of an Active Galactic Nucleus in the Late-type Galaxy NGC 3621: Spitzer Spectroscopic Observations
S. Satyapal, D. Vega, T. Heckman +2
We report the discovery of an Active Galactic Nucleus (AGN) in the nearby SAd galaxy NGC 3621 using Spitzer high spectral resolution observations. These observations reveal the pre…
Mid-Infrared Fine Structure Line Ratios in Active Galactic Nuclei Observed with Spitzer IRS: Evidence for Extinction by the Torus
R. P. Dudik, J. C. Weingartner, S. Satyapal +3
We present the first systematic investigation of the [NeV] (14um/24um) and [SIII] (18um/33um) infrared line flux ratios, traditionally used to estimate the density of the ionized g…
The PAH Emission Deficit In Low-Metallicity Galaxies - A Spitzer View
B. O'Halloran, S. Satyapal, R. P. Dudik
Archival observations of 18 starburst galaxies that span a wide range in metallicity reveal for the first time a correlation between the ratio of emission line fluxes of [FeII] at…
The Link Between Star Formation and Accretion in LINERs: A Comparison with other AGN Subclasses
S. Satyapal, R. P. Dudik, B. O'Halloran +1
We present archival high resolution X-ray imaging observations of 25 nearby LINERs observed by ACIS on board Chandra. This sample builds on our previously published proprietary and…