Nicola Bennert

Shell Galaxies, Dynamical Friction, and Dwarf Disruption (2009)

Ebrova, Ivana, Jungwiert, Bruno, Canalizo, Gabriela, Bennert, Nicola, Jilkova, Lucie

Using N-body simulations of shell galaxies created in nearly radial minor mergers, we investigate the error of collision dating, resulting from the neglect of dynamical friction and of gradual...

Shell Galaxies: Dynamical Friction, Gradual Satellite Decay and Merger Dating (2009)

Ebrova, Ivana, Jungwiert, Bruno, Canalizo, Gabriela, Bennert, Nicola, Jilkova, Lucie

With the goal to refine modelling of shell galaxies and the use of shells to probe the merger history, we develop a new method for implementing dynamical friction in test-particle simulations of...

The Lick AGN Monitoring Project: Broad-Line Region Radii and Black Hole Masses from Reverberation Mapping of Hbeta (2009)

Bentz, Misty C., Walsh, Jonelle L., Barth, Aaron J., Baliber, Nairn, Bennert, Nicola, Canalizo, Gabriela, ...

We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z < 0.05)...

Galaxy Zoo Green Peas: Discovery of A Class of Compact Extremely Star-Forming Galaxies (2009)

Cardamone, Carolin N., Schawinski, Kevin, Sarzi, Marc, Bamford, Steven P., Bennert, Nicola, Urry, C. M., ...

We investigate a class of rapidly growing emission line galaxies, known as "Green Peas", first noted by volunteers in the Galaxy Zoo project because of their peculiar bright green colour and small...

Galaxy Zoo : 'Hanny's Voorwerp', a quasar light echo? (2009)

Lintott, Chris, Schawinski, Kevin, Keel, William, Van Arkel, Hanny, Bennert, Nicola, Edmondson, Edward, ...

We report the discovery of an unusual object near the spiral galaxy IC 2497, discovered by visual inspection of the Sloan Digital Sky Survey (SDSS) as part of the Galaxy Zoo project. The object,...

A Search for H2O Megamasers in High-z Type-2 AGNs (2009)

Bennert, Nicola, Barvainis, Richard, Henkel, Christian, Antonucci, Robert

We report a search for H2O megamasers in 274 SDSS type-2 AGNs (0.3 < z < 0.83), half of which can be classified as type-2 QSOs from their [OIII] 5007 luminosity, using the Robert C. Byrd Green Bank...

First Results from the Lick AGN Monitoring Project: The Mass of the Black Hole in Arp 151 (2008)

Bentz, Misty C., Walsh, Jonelle L., Barth, Aaron J., Baliber, Nairn, Bennert, Nicola, Canalizo, Gabriela, ...

We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 13 nearby (z < 0.05)...

Fueling QSOs: The Relevance of Mergers (2008)

Bennert, Nicola, Canalizo, Gabriela, Jungwiert, Bruno, Stockton, Alan, Schweizer, Francois, Peng, Chien Y., ...

To study the relevance of mergers for the fueling of QSOs, we are currently conducting an HST imaging campaign of a sample of QSO host galaxies classified as ellipticals in the literature. Here, we...

Evidence for merger remnants in early-type host galaxies of low-redshift QSOs (2008)

Bennert, Nicola, Canalizo, Gabriela, Jungwiert, Bruno, Stockton, Alan, Schweizer, Francois, Peng, Chien Y., ...

We present results from a pilot HSTACS deep imaging study in broadband Vof five low-redshift QSO host galaxies classified in the literature as ellipticals. The aim of our study is to determine...

Evidence for Merger Remnants in Early-Type Host Galaxies of Low-Redshift QSOs (2008)

Bennert, Nicola, Canalizo, Gabriela, Jungwiert, Bruno, Stockton, Alan, Schweizer, Francois, Peng, Chien Y., ...

We present results from a pilot HST ACS deep imaging study in broad-band V of five low-redshift QSO host galaxies classified in the literature as ellipticals. The aim of our study is to determine...

2 (2007)

S. Collin, F. Combes, I. Shlosman, Heino Falcke, Nicola Bennert, Hartmut Schulz, ...

Abstract. We have observed the [OIII] 5007 line emission of seven PG quasars with the Hubble Space Telescope using linear-ramp lters. Two quasars show compact lamentary structures which may be...

Spectacular shells in the host galaxy of the QSO MC2 1635+119 (2007)

Canalizo, Gabriela, Bennert, Nicola, Jungwiert, Bruno, Stockton, Alan, Schweizer, François, Lacy, Mark, ...

We present deep HST ACS images and Keck spectroscopy of MC2 1635+119, a QSO hosted by a galaxy previously classified as an undisturbed elliptical galaxy. Our new images reveal dramatic shell...

Searching for Mergers in Early-Type QSO Host Galaxies and a Control Sample of Inactive Ellipticals (2007)

Bennert, Nicola, Canalizo, Gabriela, Jungwiert, Bruno, Stockton, Alan, Schweizer, Francois, Peng, Chien, ...

We present very deep HST/ACS images of five QSO host galaxies, classified as undisturbed ellipticals in earlier studies. For four of the five objects, our images reveal strong signs of interaction...

Spectacular Shells in the Host Galaxy of the QSO MC2 1635+119 (2007)

Canalizo, Gabriela, Bennert, Nicola, Jungwiert, Bruno, Stockton, Alan, Schweizer, Francois, Lacy, Mark, ...

We present deep HST/ACS images and Keck spectroscopy of MC2 1635+119, a QSO hosted by a galaxy previously classified as an undisturbed elliptical. Our new images reveal dramatic shell structure...

Properties of the Narrow-Line Region in Seyfert Galaxies (2006)

Bennert, Nicola, Jungwiert, Bruno, Komossa, Stefanie, Haas, Martin, Chini, Rolf

We study the narrow-line region (NLR) of six Seyfert-1 and six Seyfert-2 galaxies by means of spatially resolved optical spectroscopy and photoionization modelling. From spatially resolved spectral...

Size and properties of the narrow-line region in Seyfert-1 galaxies from spatially-resolved optical spectroscopy (2006)

Bennert, Nicola, Jungwiert, Bruno, Komossa, Stefanie, Haas, Martin, Chini, Rolf

Spatially resolved emission-line spectroscopy is a powerful tool to determine the physical conditions in the narrow-line region (NLR) of active galactic nuclei (AGNs). We recently used optical...

The radio structure of radio-quiet quasars (2006)

Leipski, Christian, Falcke, Heino, Bennert, Nicola, Huettemeister, Susanne

We investigate the radio emitting structures of radio-quiet active galactic nuclei with an emphasis on radio-quiet quasars to study their connection to Seyfert galaxies. We present and analyse...

Size and properties of the narrow-line region in Seyfert-2 galaxies from spatially-resolved optical spectroscopy (2006)

Bennert, Nicola, Jungwiert, Bruno, Komossa, Stefanie, Haas, Martin, Chini, Rolf

While [OIII] narrow-band imaging is commonly used to measure the size of the narrow-line regions (NLRs) in active galactic nuclei (AGNs), it can be contaminated by emission from surrounding...

Size and Properties of the NLR in the Seyfert-2 Galaxy NGC 1386 (2005)

Bennert, Nicola, Jungwiert, Bruno, Komossa, Stefanie, Haas, Martin, Chini, Rolf

We study the narrow-line region (NLR) of the Seyfert-2 galaxy NGC 1386 by means of long-slit spectroscopy obtained with FORS1 at the VLT. We use the galaxy itself for subtracting the stellar...

[OIII] profile substructure in radio-quiet quasars (2005)

Leipski, Christian, Bennert, Nicola

Interactions between the radio jet and the optical emission of the narrow-line region (NLR) are a well known phenomenon in Seyfert galaxies. Here, we present the study of possible jet-NLR...

The narrow-line region of active galaxies (2005)

Bennert, Nicola

In dieser Arbeit wird die Narrow-Line Region (NLR) in Aktiven Galaktischen Kernen (AGN) mit Hilfe von Bildern und Spektroskopie untersucht. Es besteht ein Zusammenhang zwischen Größe und...

Comparing AGN broad- and narrow-line regions (2004)

Bennert, Nicola, Falcke, Heino, Shchekinov, Yuri, Wilson, Andrew S.

We compare recent HST observations of Seyfert and quasar NLRs and find that type-2 AGNs follow a relation consistent with that expected for a distribution of gas ionized by a central source R(NLR,2)...

Spectral characteristics of water megamaser galaxies II: ESO 103-G035, TXS 2226-184, and IC 1481 (2004)

Bennert, Nicola, Schulz, Hartmut, Henkel, Christian

Long-slit optical emission-line spectra of the H2O megamaser galaxies ESO 103-G03, TXS 2226-184, and IC 1481 are evaluated in order to look for characteristics typical for water-megamaser galaxies....

Size and Structure of the Narrow-Line Region of Quasars (2002)

Bennert, Nicola, Falcke, Heino, Schulz, Hartmut, Wilson, Andrew S., Wills, Beverley J.

We have observed the narrow-line regions (NLRs) of the seven brightest radio-quiet PG (or BQS) quasars (z < 0.5) with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope (HST)....

Size And Structure Of The Narrow-Line Region Of Quasars (2001)

Nicola Bennert, Heino Falcke, Hartmut Schulz, Andrew S. Wilson, Beverley J. Wills

We have observed the narrow{line regions (NLRs) of the seven brightest radio{quiet PG (or BQS) quasars (z < 0.5) with the Wide Field Planetary Camera 2 on board the Hubble Space Telescope (HST)....