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The supermassive black hole and double nucleus of the core elliptical NGC 5419
Bender, Ralf; Thomas, Jens; Fabricius, Maximilian H. +5 more
We obtained adaptive-optics assisted SINFONI observations of the central regions of the giant elliptical galaxy NGC 5419 with a spatial resolution of 0.2 arcsec (≈55 pc). NGC 5419 has a large depleted stellar core with a radius of 1.58 arcsec (430 pc). HST and SINFONI images show a point source located at the galaxy's photocentre, which is likely …
A Hot Gaseous Galaxy Halo Candidate with Mg X Absorption
Bregman, Joel N.; Qu, Zhijie
The hot gas in galaxy halos may account for a significant fraction of missing baryons in galaxies, and some of these gases can be traced by high ionization absorption systems in QSO UV spectra. Using high S/N Hubble Space Telescope/Cosmic Origins Spectrograph spectra, we discovered a high ionization state system at z = 1.1912 in the sightline towa…
Discovery of X-Ray Emission from the Galactic Supernova Remnant G32.8-0.1 with Suzaku
Safi-Harb, Samar; Petre, Robert; Terada, Yukikatsu +6 more
We present the first dedicated X-ray study of the supernova remnant (SNR) G32.8-0.1 (Kes 78) with Suzaku. X-ray emission from the whole SNR shell has been detected for the first time. The X-ray morphology is well correlated with the emission from the radio shell, while anti-correlated with the molecular cloud found in the SNR field. The X-ray spec…
X-rays beware: the deepest Chandra catalogue of point sources in M31
Barmby, P.; Vulic, N.; Gallagher, S. C.
This study represents the most sensitive Chandra X-ray point source catalogue of M31. Using 133 publicly available Chandra ACIS-I/S observations totalling ∼1 Ms, we detected 795 X-ray sources in the bulge, north-east, and south-west fields of M31, covering an area of ≈0.6 deg2, to a limiting unabsorbed 0.5-8.0 keV luminosity of ∼10…
The distribution of dark and luminous matter in the unique galaxy cluster merger Abell 2146
McNamara, Brian R.; Fabian, Andrew C.; Santana, Rebecca +9 more
Abell 2146 (z = 0.232) consists of two galaxy clusters undergoing a major merger. The system was discovered in previous work, where two large shock fronts were detected using the Chandra X-ray Observatory, consistent with a merger close to the plane of the sky, caught soon after first core passage. A weak gravitational lensing analysis of the tota…
Level of helium enhancement among M3's horizontal branch stars
Contreras Ramos, R.; Catelan, M.; Alonso-García, J. +2 more
Context. The color and luminosity distribution of horizontal branch (HB) stars in globular clusters (GCs) are sensitive probes of the original helium abundances of those clusters. In this sense, recently the distributions of HB stars in GC color-magnitude diagrams (CMDs) have been extensively used as indicators of possible variations in the helium…
Source Regions of the Type II Radio Burst Observed During a CME-CME Interaction on 2013 May 22
Krupar, V.; Gopalswamy, N.; Mäkelä, P. +2 more
We report on our study of radio source regions during the type II radio burst on 2013 May 22 based on direction-finding analysis of the Wind/WAVES and STEREO/WAVES (SWAVES) radio observations at decameter-hectometric wavelengths. The type II emission showed an enhancement that coincided with the interaction of two coronal mass ejections (CMEs) lau…
Systematic processing of Mars Express HRSC panchromatic and colour image mosaics: Image equalisation using an external brightness reference
Jaumann, R.; van Gasselt, S.; Dumke, A. +8 more
After more than ten years in orbit at Mars, the coverage from the High Resolution Stereo Camera (HRSC) on the European Space Agency's Mars Express is sufficient to begin constructing mosaic products on a global scale. We describe our systematic processing procedure and, in particular, the technique used to bring images affected by atmospheric dust…
Stellar Boron Abundances near the Main-sequence Turnoff of the Open Cluster NGC 3293 and Implications for the Efficiency of Rotationally Driven Mixing in Stellar Envelopes
Langer, Norbert; Proffitt, Charles R.; Lennon, Daniel J. +1 more
Spectra from the Hubble Space Telescope Cosmic Origins Spectrograph and the Space Telescope Imaging Spectrograph covering the B III resonance line have been obtained for 10 early-B stars near the turnoff of the young Galactic open cluster NGC 3293. This is the first sample of boron abundance determinations in a single, clearly defined population o…
Observation and Analysis of Ballistic Downflows in an M-class Flare with the Interface Region Imaging Spectrograph
Brannon, Sean R.
Despite significant advances in instrumentation, there remain no studies that analyze observations of on-disk flare loop plasma flows covering the entire evolution from chromospheric evaporation, through plasma cooling, to draining downflows. We present results from an imaging and spectroscopic observation from the Interface Region Imaging Spectro…