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XMM-Newton, Chandra, and CGPS observations of the Supernova Remnants G85.4+0.7 and G85.9-0.6
Jackson, M. S.; Safi-Harb, S.; Kothes, R. +1 more
We present an XMM-Newton detection of two low radio surface brightness supernova remnants (SNRs), G85.4+0.7 and G85.9-0.6, discovered with the Canadian Galactic Plane Survey (CGPS). High-resolution XMM-Newton images revealing the morphology of the diffuse emission, as well as discrete point sources, are presented and correlated with radio and Chan…
The Structure of the DoAr 25 Circumstellar Disk
Wilner, D. J.; Andrews, Sean M.; Qi, Chunhua +1 more
We present high spatial resolution (lsim 0.3'' ≈ 40 AU) Submillimeter Array observations of the 865 µm continuum emission from the circumstellar disk around the young star DoAr 25. Despite its bright millimeter emission, this source exhibits only a comparatively small infrared excess and low accretion rate, suggesting that the material and s…
The Lack of Strong O-Line Excess in the Coma Cluster Outskirts from Suzaku
Miller, Eric D.; Bregman, Joel N.; Ohashi, Takaya +6 more
About half of the baryons in the local universe are thought to reside in the so-called warm-hot intergalactic medium (WHIM) at temperatures of 0.1-10 MK. Thermal soft excess emission in the spectrum of some cluster outskirts that contains O VII and/or O VIII emission lines is regarded as evidence of the WHIM, although the origin of the lines is co…
Magnetic Twist of EUV Coronal Loops Well-traced in TRACE Images: Evidence for Magnetic Reconnection Origin of Coronal Loops?
Chae, Jongchul; Kwon, Ryun Young
The measurements of magnetic twist of EUV coronal loops for 14 loops are presented here. EUV coronal loops are thin, EUV-emitting structures of hot plasma tracing magnetic field lines in the corona. The constriction of plasma into a loop without dispersion may be explained if the magnetic field of the loop is twisted. On the basis of this idea, Ch…
Hubble Space Telescope Images of Red Mergers: How Dry Are They?
van Dokkum, Pieter G.; Whitaker, Katherine E.
Mergers between red galaxies are observed to be common in the nearby universe, and are thought to be the dominant mechanism by which massive galaxies grow their mass at late times. These "dry" mergers can be readily identified in very deep ground-based images, thanks to their extended low surface brightness tidal features. However, ground-based im…
Observation of an Extended Very High Energy Gamma-Ray Emission from MSH 15-52 with CANGAROO-III
Katagiri, H.; Edwards, P. G.; Gunji, S. +46 more
We have observed the supernova remnant MSH 15-52 (G320.4-1.2), which contains the gamma-ray pulsar PSR B1509-58, using the CANGAROO-III imaging atmospheric Cerenkov telescope array from 2006 April to June. We detected gamma rays above 810 GeV at the 7 σ level during a total effective exposure of 48.4 hr. We obtained a differential gamma-ray flux a…
A Study of H2 Emission in Three Bipolar Proto-Planetary Nebulae: IRAS 16594-4656, Hen 3-401, and Rob 22
Smith, Nathan; Hrivnak, Bruce J.; Su, Kate Y. L. +1 more
We have carried out a spatial-kinematic study of three proto-planetary nebulae, IRAS 16594-4656, Hen 3-401, and Rob 22. High-resolution H2 images were obtained with NICMOS on the Hubble Space Telescope, and high-resolution spectra were obtained with the Phoenix spectrograph on Gemini-South. IRAS 16594-4656 shows a "peanut-shaped" bipola…
A Chandra Look at Five of the Broadest Double-Peaked Balmer Line Emitters
Brandt, W. N.; Eracleous, Michael; Garmire, Gordon +1 more
We study the 0.5-10 keV emission of a sample of five of the broadest double-peaked Balmer line emitters with Chandra. The Balmer lines of these objects originate close (within a few hundred gravitational radii) to the central black holes of the active galactic nuclei (AGNs), and their double-peaked profiles suggest an origin in the AGN accretion d…
Minor Ion Abundances in the Slow Solar Wind
Wurz, P.; Karrer, R.; Giammanco, C.
In this paper we report for the first time the absolute abundance of P (AP = 6.1 +/- 0.5), Al (AAl = 7.2 +/- 0.2), K (AK = 5.7 +/- 0.4), and Na (ANa = 6.5 +/- 0.3) in the slow solar wind for three wind speed ranges (380, 390, 400 km s-1, with a tolerance of ±2 km s-1) using 4 years …
On the Stellar Populations in Faint Red Galaxies in the Hubble Ultra Deep Field
Papovich, Casey; Eisenstein, Daniel J.; Stutz, Amelia M.
We study the nature of faint red-selected galaxies at z ~ 2-3 using the Hubble Ultra Deep Field (HUDF) and Spitzer Infrared Array Camera (IRAC) photometry. Given the magnitude limit of the HST data, we detect candidate galaxies to HAB < 26 mag, probing lower luminosity (lower mass) galaxies at these redshifts. We identify 32 galaxies…