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Evidence for Merger Remnants in Early-Type Host Galaxies of Low-Redshift QSOs
Schweizer, François; Lacy, Mark; Stockton, Alan +4 more
We present results from a pilot HST ACS deep imaging study in broadband V of five low-redshift QSO host galaxies classified in the literature as ellipticals. The aim of our study is to determine whether these early-type hosts formed at high redshift and have since evolved passively, or whether they have undergone relatively recent mergers that may…
Flows in active region loops observed by Hinode EIS
Del Zanna, G.
We aim to investigate the overall characteristics of coronal active region loops and their evolution. The Hinode database was searched for observations of active regions as they crossed the Sun centre. NOAA 10926 was selected. The morphology of this young active region did not significantly change over the course of a few days. Persistent redshift…
Flare Irradiance Spectral Model (FISM): Flare component algorithms and results
Chamberlin, Phillip C.; Woods, Thomas N.; Eparvier, Francis G.
The Flare Irradiance Spectral Model (FISM) is an empirical model developed for space weather applications that estimates the solar irradiance at wavelengths from 0.1 to 190 nm at 1 nm resolution with a time cadence of 60 s. This is a high enough temporal resolution to model variations due to solar flares, where few accurate measurements at these w…
Detection of hot gas in the filament connecting the clusters of galaxies Abell 222 and Abell 223
Finoguenov, A.; Böhringer, H.; Simionescu, A. +4 more
Context: About half of the baryons in the local Universe are invisible and - according to simulations - their dominant fraction resides in filaments connecting clusters of galaxies in the form of low density gas with temperatures in the range of 105 < T < 107 K. This warm-hot intergalactic medium has never been detected…
Quantitative Spectroscopy of 24 A Supergiants in the Sculptor Galaxy NGC 300: Flux-weighted Gravity-Luminosity Relationship, Metallicity, and Metallicity Gradient
Bresolin, Fabio; Kudritzki, Rolf-Peter; Urbaneja, Miguel A. +3 more
A quantitative spectral analysis of 24 A supergiants in the Sculptor Group spiral galaxy NGC 300 at a distance of 1.9 Mpc is presented. A new method is introduced to analyze low-resolution (~5 Å) spectra, which yields metallicities accurate to 0.2 dex including the uncertainties arising from the errors in Teff (5%) and log g (0.2 dex). …
Black Holes in Pseudobulges and Spheroidals: A Change in the Black Hole-Bulge Scaling Relations at Low Mass
Ho, Luis C.; Barth, Aaron J.; Greene, Jenny E.
We investigate the relationship between black hole mass and host galaxy properties for active galaxies with the lowest black hole masses currently known in galaxy nuclei. HST imaging confirms that the host galaxies have correspondingly low luminosity; they are ~1 mag below L*. In terms of morphology, ~60% of the members of the sample are disk domi…
Mapping of molecular gas inflow towards the Seyfert nucleus of NGC4051 using Gemini NIFS
Storchi-Bergmann, Thaisa; Riffel, Rogemar A.; Winge, Cláudia +3 more
We present 2D stellar and gaseous kinematics of the inner ~130×180 pc2 of the Narrow-Line Seyfert 1 galaxy NGC4051 at a sampling of 4.5pc, from near-infrared K-band spectroscopic observations obtained with the Gemini's Near-infrared Integral Field Spectrograph (NIFS) operating with the ALTAIR adaptive optics module. We have used the CO …
On why the iron K-shell absorption in AGN is not a signature of the local warm/hot intergalactic medium
Done, Chris; Terashima, Yuichi; Hayashida, Kiyoshi +5 more
We present a comparison between the 2001 XMM-Newton and 2005 Suzaku observations of the quasar, PG1211+143, at z = 0.0809. Variability is observed in the 7 keV iron K-shell absorption line (at 7.6 keV in the quasar frame), which is significantly weaker in 2005 than during the 2001 XMM-Newton observation. From a recombination time-scale of <4 yr…
The formation and assembly of a typical star-forming galaxy at redshift z~3
Richard, Johan; Stark, Daniel P.; Ellis, Richard S. +3 more
Recent studies of galaxies ~2-3Gyr after the Big Bang have revealed large, rotating disks, similar to those of galaxies today. The existence of well-ordered rotation in galaxies during this peak epoch of cosmic star formation indicates that gas accretion is likely to be the dominant mode by which galaxies grow, because major mergers of galaxies wo…
Hubble Space Telescope STIS Optical Transit Transmission Spectra of the Hot Jupiter HD 209458b
Sing, David K.; Lecavelier des Etangs, A.; Vidal-Madjar, A. +2 more
We present the transmission spectra of the hot Jupiter HD 209458b taken with the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope. Our analysis combines data at two resolutions and applies a complete pixel-by-pixel limb-darkening correction to fully reveal the spectral line shapes of atmospheric absorption features. Terrestri…