Search Results - "Onken, Christopher"

SkyMapper colours of Seyfert galaxies and changing-look AGN – II. Newly discovered changing-look AGN by Hon, Wei Jeat, Wolf, Christian, Onken, Christopher A, Webster, Rachel, Auchettl, Katie

“…Changing-look active galactic nuclei (CLAGN) are AGN that change type as their broad emission lines appear or disappear, which is usually accompanied by strong…”
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Reverberation Mapping of IC 4329A by Bentz, Misty C., Onken, Christopher A., Street, Rachel, Valluri, Monica

“…We present the results of a new reverberation mapping campaign for the broad-line active galactic nucleus (AGN) in the edge-on spiral IC 4329A. Monitoring of…”
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Supermassive black holes are growing slowly by z∼5 by Lai, Samuel, Onken, Christopher A, Wolf, Christian, Bian, Fuyan, Fan, Xiaohui

“…We investigate the black hole mass function at z ∼ 5 using XQz5, our recent sample of the most luminous quasars between the redshifts 4.5 < z < 5.3. We include…”
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An expanded Mbh-σ diagram, and a new calibration of active galactic nuclei masses by Graham, Alister W., Onken, Christopher A., Athanassoula, E., Combes, F.

“…ABSTRACT We present an updated and improved Mbh–σ diagram containing 64 galaxies for which Mbh measurements (not just upper limits) are available. Because of…”
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Robotic Reverberation Mapping of the Southern Seyfert NGC 3783 by Bentz, Misty C., Street, Rachel, Onken, Christopher A., Valluri, Monica

“…We present spectroscopic and photometric monitoring of NGC 3783 conducted throughout the first half of 2020. Time delays between the continuum variations and…”
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Ultraluminous quasars at high redshift show evolution in their radio-loudness fraction in both redshift and ultraviolet luminosity by Lah, Philip, Onken, Christopher A, Norris, Ray P, D’Eugenio, Francesco

“…ABSTRACT We take a sample of 94 ultraluminous, optical quasars from the search of over 14 486 deg2 by Onken et al. in the range 4.4 < redshift < 5.2 and match…”
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Discovery of a new blue large-amplitude pulsator in the SkyMapper DR2: SMSS J184506.82−300804.7 by Chang, Seo-Won, Wolf, Christian, Onken, Christopher A, Bessell, Michael S

“…ABSTRACT We report the discovery of a new Blue Large-Amplitude Pulsator (BLAP), SMSS J184506−300804 (SMSS-BLAP-1) in Data Release 2 of the SkyMapper Southern…”
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Virial black hole mass estimates of quasars in the XQ-100 legacy survey by Lai, Samuel, Onken, Christopher A, Wolf, Christian, Bian, Fuyan, Cupani, Guido, Lopez, Sebastian, D’Odorico, Valentina

“…ABSTRACT The black hole (BH) mass and luminosity are key factors in determining how a quasar interacts with its environment. In this study, we utilize data…”
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Beyond Spectroscopy. I. Metallicities, Distances, and Age Estimates for Over 20 Million Stars from SMSS DR2 and Gaia EDR3 by Huang, Yang, Beers, Timothy C., Wolf, Christian, Lee, Young Sun, Onken, Christopher A., Yuan, Haibo, Shank, Derek, Zhang, Huawei, Wang, Chun, Shi, Jianrong, Fan, Zhou

“…Accurate determinations of stellar parameters and distances for large complete samples of stars are keys for conducting detailed studies of the formation and…”
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Spatially dependent photometric activity of M dwarfs in the solar cylinder by Chang, Seo-Won, Wolf, Christian, Onken, Christopher A

“…We study the relationship between Galactic location (R, Z) and photometric activity for 3.6 million M dwarf stars within 1 kpc of the Sun. For this purpose, we…”
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Photometric flaring fraction of M dwarf stars from the SkyMapper Southern Survey by Chang, Seo-Won, Wolf, Christian, Onken, Christopher A

“…We present our search for flares from M dwarf stars in the SkyMapper Southern Survey DR1, which covers nearly the full Southern hemisphere with six-filter…”
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SkyMapper colours of Seyfert galaxies and Changing-Look AGN by Wolf, Christian, Golding, Jacob, Hon, Wei Jeat, Onken, Christopher A

“…ABSTRACT We study the utility of broad-band colours in the SkyMapper Southern Survey for selecting Seyfert galaxies at low luminosity. We find that the u − v…”
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Velocity-resolved Reverberation Mapping of NGC 3227 by Bentz, Misty C., Markham, Madison, Rosborough, Sara, Onken, Christopher A., Street, Rachel, Valluri, Monica, Treu, Tommaso

“…We describe the results of a new reverberation mapping program focused on the nearby Seyfert galaxy NGC 3227. Photometric and spectroscopic monitoring was…”
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The Mass of the Black Hole in NGC 5273 from Stellar Dynamical Modeling by Merrell, Katie A., Vasiliev, Eugene, Bentz, Misty C., Valluri, Monica, Onken, Christopher A.

“…We present a new constraint on the mass of the black hole in the active S0 galaxy NGC 5273. Due to the proximity of the galaxy at 16.6 ± 2.1 Mpc, we were able…”
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The Black Hole Mass of NGC 4151 from Stellar Dynamical Modeling by Roberts, Caroline A., Bentz, Misty C., Vasiliev, Eugene, Valluri, Monica, Onken, Christopher A.

“…The mass of a supermassive black hole ( M BH ) is a fundamental property that can be obtained through observational methods. Constraining M BH through multiple…”
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A Detailed View of the Broad-line Region in NGC 3783 from Velocity-resolved Reverberation Mapping by Bentz, Misty C., Williams, Peter R., Street, Rachel, Onken, Christopher A., Valluri, Monica, Treu, Tommaso

“…We have modeled the full velocity-resolved reverberation response of the H β and He ii optical broad emission lines in NGC 3783 to constrain the geometry and…”
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Ultraluminous high-redshift quasars from SkyMapper – II. New quasars and the bright end of the luminosity function by Onken, Christopher A, Wolf, Christian, Bian, Fuyan, Fan, Xiaohui, Hon, Wei Jeat, Raithel, David, Tisserand, Patrick, Lai, Samuel

“…ABSTRACT We search for ultraluminous Quasi-Stellar Objects (QSOs) at high redshift using photometry from the SkyMapper Southern Survey Data Release 3 (DR3), in…”
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Chemical abundance of z ~ 6 quasar broad-line regions in the XQR-30 sample by Onken, Christopher A, Wolf, Christian, Mazzucchelli, Chiara, Bañados, Eduardo, Bischetti, Manuela, Bosman, Sarah E I, Becker, George, Cupani, Guido, D’Odorico, Valentina, Eilers, Anna-Christina, Fan, Xiaohui, Farina, Emanuele Paolo, Onoue, Masafusa, Schindler, Jan-Torge, Walter, Fabian, Wang, Feige, Yang, Jinyi, Zhu, Yongda

“…ABSTRACT The elemental abundances in the broad-line regions of high-redshift quasars trace the chemical evolution in the nuclear regions of massive galaxies in…”
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Characterising SMSS J2157–3602, the most luminous known quasar, with accretion disc models by Lai (赖民希), Samuel, Wolf, Christian, Onken, Christopher A, Bian (边福彦), Fuyan

“…ABSTRACT We develop an accretion disc (AD)-fitting method, utilizing thin and slim disc models and Bayesian inference with the Markov-Chain Monte Carlo…”
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A thirty-four billion solar mass black hole in SMSS J2157–3602, the most luminous known quasar by Onken, Christopher A, Bian, Fuyan, Fan, Xiaohui, Wang, Feige, Wolf, Christian, Yang, Jinyi

“…ABSTRACT From near-infrared spectroscopic measurements of the Mg ii emission line doublet, we estimate the black hole (BH) mass of the quasar, SMSS…”
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