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Abundance Variation at the Vicinity of an Active Region and the Coronal Origin of the Slow Solar Wind
Raymond, John C.; Riley, Pete; Zurbuchen, Thomas H. +3 more
The solar wind ion composition is generally ``frozen-in'' within 5 Rsolar of the Sun. Many characteristics in the elemental abundances measured in the solar wind are believed to be set at the chromospheric and low coronal levels. By connecting plasma parameters in the coronal and in situ solar wind data, valuable insights can be obtaine…
Discovery of Outlying High-Velocity Oxygen-Rich Ejecta in Cassiopeia A
Chevalier, Roger A.; Raymond, John C.; Dopita, Michael A. +7 more
Analysis of broadband HST ACS and WFPC2 images of the young Galactic supernova remnant Cassiopeia A reveals a far larger population of outlying, high-velocity knots of ejecta with a broader range of chemical properties than previously suspected. In this paper, we concentrate on a ~=1.5 arcmin2 region located along the eastern limb of th…
Radio Measurements of the Height of Strong Coronal Magnetic Fields Above Sunspots at the Solar Limb
Brosius, Jeffrey W.; White, Stephen M.
We measure coronal magnetic field strengths of 1750 G at a height of 8000 km above a large sunspot in NOAA AR 10652 at the west solar limb on 2004 July 29 using coordinated observations with the Very Large Array, the Transition Region and Coronal Explorer, and three instruments (CDS, EIT, MDI) aboard the Solar and Heliospheric Observatory. This ob…
First Results from the CHARA Array. III. Oblateness, Rotational Velocity, and Gravity Darkening of Alderamin
Ciardi, D. R.; Berger, D. H.; Goldfinger, P. J. +10 more
We present observations of the A7 IV-V star Alderamin (α Cep, HR 8162, HD 203280) from the Georgia State University CHARA Array. These infrared interferometric angular size measurements indicate a noncircular projected disk brightness distribution for this known rapid rotator. The interferometric observations are modeled as arising from an elongat…
M33 X-7: ChASeM33 Reveals the First Eclipsing Black Hole X-Ray Binary
Pietsch, W.; Haberl, F.; Long, K. S. +5 more
The first observations conducted as part of the Chandra ACIS survey of M33 (ChASeM33) sampled the eclipsing X-ray binary M33 X-7 over a large part of the 3.45 day orbital period and have resolved eclipse ingress and egress for the first time. The occurrence of the X-ray eclipse allows us to determine an improved ephemeris of mid-eclipse and binary…
A Multiwavelength Study of the Pulsar PSR B1929+10 and Its X-Ray Trail
Taam, Ronald E.; Caraveo, Patrizia A.; Mignani, Roberto +8 more
We report on the emission properties of PSR B1929+10 and its putative trail from a multiwavelength study performed using optical, X-ray, and radio data. XMM-Newton observations confirm the existence of the diffuse emission with a trail morphology lying in a direction opposite to the transverse motion of the pulsar. The trail spectrum is nonthermal…
Observing Cold Gas in Submillimeter Galaxies: Detection of CO (1-->0) Emission in SMM J13120+4242 with the Green Bank Telescope
Ivison, R. J.; Smail, Ian; Greve, T. R. +3 more
We report the first detection of CO (1-->0) emission from a submillimeter-selected galaxy, using the Green Bank Telescope. We identify the line in the spectrum of SMM J13120+4242 as a broad emission feature at z=3.408, with ΔVFWHM=1040+/-190 km s-1. If the observed CO (1-->0) line profile arises from a single object and…
Line Strengths in Early-Type Cluster Galaxies at z = 0.33: Implications for α/Fe, Nitrogen, and the Histories of E/S0s
Franx, Marijn; Kelson, Daniel D.; Illingworth, Garth D. +1 more
In this paper we analyze previously published spectra with high signal-to-noise ratios of E/S0s in the rich cluster CL 1358+62 at z=0.33. Introducing techniques for fitting stellar population models to the data, we focus on the 19 Es and S0s with a homogeneous set of eight blue Lick indices. We explore the galaxy properties using six-parameter ste…
Two Populations of Young Massive Star Clusters in Arp 220
Wilson, Christine D.; Scoville, N. Z.; Harris, William E. +1 more
We present new optical observations of young massive star clusters in Arp 220, the nearest ultraluminous infrared galaxy, taken in UBVI with the Hubble Space Telescope ACS HRC camera. We find a total of 206 probable clusters whose spatial distribution is centrally concentrated toward the nucleus of Arp 220. We use model star cluster tracks to dete…
Integral Field Spectroscopy of the Luminous Infrared Galaxy Arp 299 (IC 694 + NGC 3690)
Colina, L.; Arribas, S.; Alonso-Herrero, A. +2 more
The luminous infrared galaxy Arp 299 (IC 694 + NGC 3690) is studied using optical integral field spectroscopy obtained with the INTEGRAL system, together with archival Hubble Space Telescope WFPC2 and NICMOS images. The stellar and ionized gas morphology shows λ-dependent variations due to the combined effects of the dust internal extinction and t…