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Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Astrophysics and Astronomy

Aerospace, Physics, and Space Science Faculty Publications

Series

2015

Galaxies: Nuclei

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

Chang-Es V: Nuclear Outflow In A Virgo Cluster Spiral After A Tidal Disruption Event, Judith A. Irwin, Richard N. Henriksen, Marita Krause, Daniel Q. Wang, Theresa Wiegert, Eric J. Murphy, George Heald, Eric S. Perlman Aug 2015

Chang-Es V: Nuclear Outflow In A Virgo Cluster Spiral After A Tidal Disruption Event, Judith A. Irwin, Richard N. Henriksen, Marita Krause, Daniel Q. Wang, Theresa Wiegert, Eric J. Murphy, George Heald, Eric S. Perlman

Aerospace, Physics, and Space Science Faculty Publications

We have observed the Virgo Cluster spiral galaxy, NGC 4845, at 1.6 and 6 GHz using the Karl G. Jansky Very Large Array, as part of the Continuum Halos in Nearby Galaxies—an EVLA Survey (CHANG-ES). The source consists of a bright unresolved core with a surrounding weak central disk (1.8 kpc diameter). The core is variable over the 6 month timescale of the CHANG-ES data and has increased by a factor of ≈6 since 1995. The wide bandwidths of CHANG-ES have allowed us to determine the spectral evolution of this core, which peaks between 1.6 and 6 GHz (it is …


The Differences In The Torus Geometry Between Hidden And Non-Hidden Broad Line Active Galactic Nuclei, Kohei Ichikawa, Eric S. Perlman Apr 2015

The Differences In The Torus Geometry Between Hidden And Non-Hidden Broad Line Active Galactic Nuclei, Kohei Ichikawa, Eric S. Perlman

Aerospace, Physics, and Space Science Faculty Publications

We present results from the fitting of infrared (IR) spectral energy distributions of 21 active galactic nuclei (AGNs) with clumpy torus models. We compiled high spatial resolution (∼0.3–0.7 arcsec) mid-IR (MIR) N-band spectroscopy, Q-band imaging, and nuclear near- and MIR photometry from the literature. Combining these nuclear near- and MIR observations, far-IR photometry, and clumpy torus models enables us to put constraints on the torus properties and geometry. We divide the sample into three types according to the broad line region (BLR) properties: type-1s, type-2s with scattered or hidden broad line region (HBLR) previously observed, and type-2s without any published …


Spitzer Space Telescope Measurements Of Dust Reverberation Lags In The Seyfert 1 Galaxy Ngc 6418, Billy Vazquez, Dan Batcheldor Mar 2015

Spitzer Space Telescope Measurements Of Dust Reverberation Lags In The Seyfert 1 Galaxy Ngc 6418, Billy Vazquez, Dan Batcheldor

Aerospace, Physics, and Space Science Faculty Publications

We present results from a 15 month campaign of high-cadence (∼3 days) mid-infrared Spitzer and optical (B and V) monitoring of the Seyfert 1 galaxy NGC 6418, with the objective of determining the characteristic size of the dusty torus in this active galactic nucleus (AGN). We find that the 3.6 and 4.5 μm flux variations lag behind those of the optical continuum by 37.2 ^+2.4 _-2.2 days and -47.1 ^+3.1 _-3.1 days, respectively. We report a cross-correlation time lag between the 4.5 and 3.6 μm flux of 13.9 ^+0.5 _-0.1 days. The lags indicate that the dust emitting at 3.6 …