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Secularly powered outflows from AGNs: the dominance of non-merger driven supermassive black hole growth
Simmons, B. D.; Smethurst, R. J.; Lintott, C. J. +1 more
Recent observations and simulations have revealed the dominance of secular processes over mergers in driving the growth of both supermassive black holes (SMBHs) and galaxy evolution. Here, we obtain narrow-band imaging of AGN powered outflows in a sample of 12 galaxies with disc-dominated morphologies, whose history is assumed to be merger-free. W…
Planck Far-infrared Detection of Hyper Suprime-Cam Protoclusters at z ∼ 4: Hidden AGN and Star Formation Activity
Ono, Yoshiaki; Goto, Tomotsugu; Kodama, Tadayuki +11 more
We perform a stacking analysis of Planck, AKARI, Infrared Astronomical Satellite, Wide-field Infrared Survey Explorer, and Herschel images of the largest number of (candidate) protoclusters at z ∼ 3.8 selected from the Hyper Suprime-Cam Subaru Strategic Program. Stacking the images of the 179 candidate protoclusters, the combined infrared (IR) emi…
The Matter Beyond the Ring: The Recent Evolution of SN 1987A Observed by the Hubble Space Telescope
Larsson, J.; Sollerman, J.; Lundqvist, P. +14 more
The nearby SN 1987A offers a spatially resolved view of the evolution of a young supernova (SN) remnant. Here we present recent Hubble Space Telescope imaging observations of SN 1987A, which we use to study the evolution of the ejecta, the circumstellar equatorial ring (ER), and the increasing emission from material outside the ER. We find that th…
A low-flux state in IRAS 00521-7054 seen with NuSTAR and XMM-Newton: relativistic reflection and an ultrafast outflow
Harrison, F. A.; Stern, D.; Fabian, A. C. +8 more
We present results from a deep, coordinated XMM-Newton + NuSTAR observation of the Seyfert 2 galaxy IRAS 00521-7054. The NuSTAR data provide the first detection of this source in high-energy X-rays (E > 10 keV), and the broad-band data show this to be a highly complex source which exhibits relativistic reflection from the inner accretion disc, …
Mass-loss Rates for O and Early B Stars Powering Bow Shock Nebulae: Evidence for Bistability Behavior
Kobulnicky, Henry A.; Povich, Matthew S.; Chick, William T.
Second only to initial mass, the rate of wind-driven mass loss determines the final mass of a massive star and the nature of its remnant. Motivated by the need to reconcile observational values and theory, we use a recently vetted technique to analyze the mass-loss rates in a sample of OB stars that generate bow shock nebulae. We measure peculiar …
Multipoint Study of Successive Coronal Mass Ejections Driving Moderate Disturbances at 1 au
Poedts, Stefaan; Scolini, Camilla; West, Matthew J. +10 more
We analyze in this work the propagation and geoeffectiveness of four successive coronal mass ejections (CMEs) that erupted from the Sun during 2013 May 21-23 and were detected in interplanetary space by the Wind and/or STEREO-A spacecraft. All these CMEs featured critical aspects for understanding so-called “problem space weather storms” at Earth.…
Metal-poor Stars Observed with the Automated Planet Finder Telescope. I. Discovery of Five Carbon-enhanced Metal-poor Stars from LAMOST
Zhao, Gang; Placco, Vinicius M.; Li, Haining +6 more
We report on the discovery of five carbon-enhanced metal-poor (CEMP) stars in the metallicity range of -3.3 < [Fe/H] < -2.4. These stars were selected from the LAMOST DR3 low-resolution (R ∼ 2000) spectroscopic database as metal-poor candidates and followed up with high-resolution spectroscopy (R ∼ 110,000) with the Lick/APF. Stellar paramet…
Spectral Evidence for Heating at Large Column Mass in Umbral Solar Flare Kernels. I. IRIS Near-UV Spectra of the X1 Solar Flare of 2014 October 25
Kowalski, Adam F.; De Pontieu, Bart; Kerr, Graham S. +5 more
The GOES X1 flare SOL2014-10-25T17:08:00 was a three-ribbon solar flare observed with the Interface Region Imaging Spectrograph (IRIS) in the near-UV (NUV) and far-UV. One of the flare ribbons crossed a sunspot umbra, producing a dramatic, ∼1000% increase in the NUV continuum radiation. We comprehensively analyze the UV spectral data of the umbral…
Clocking the assembly of double-barred galaxies with the MUSE TIMER project
Leaman, Ryan; Fragkoudi, Francesca; van de Ven, Glenn +11 more
The formation of two stellar bars within a galaxy has proved challenging for numerical studies. It is not yet clear whether the inner bar is born via a star formation process promoted by gas inflow along the outer bar or whether it is dynamically assembled from instabilities in a small-scale stellar disc. Observational constraints to these scenari…
Light Curves and Rotational Properties of the Pristine Cold Classical Kuiper Belt Objects
Thirouin, Audrey; Sheppard, Scott S.
We present a survey of the rotational and physical properties of the dynamically low inclination Cold Classical (CC) trans-Neptunian objects (TNOs). The CCs are primordial planetesimals and contain information about our solar system and planet formation over the first 100 million years after the Sun’s formation. We obtained partial/complete light …