Search Publications
Energetic Neutral Atoms from the Heliosheath
Barabash, S.; Grigoriev, A.; Wurz, P. +1 more
We present the measurement and analysis of hydrogen energetic neutral atoms (ENAs) recorded with the NPD sensor of the ASPERA-3 instrument on board Mars Express during the cruise phase and the Mars orbit phase. We conclude that the origin of these ENAs is the inner heliosheath. The ENA energy spectra are all very similar and can be fitted well by …
Ultraviolet Spectroscopy of HD 44179
Sitko, Michael L.; Bernstein, Lawrence S.; Glinski, Robert J.
We have reanalyzed the ultraviolet spectrum of HD 44179, the central star(s) of the Red Rectangle Nebula, providing improved estimates of the column density, rotational, and vibrational temperatures of the 4th Positive A-X system of CO in absorption. The flux shortward of 2200 Å is a complex blend of CO features with no discernible stellar photosp…
May Day! Coronal Loop Temperatures from the Hinode EUV Imaging Spectrometer
Schmelz, J. T.; Scott, J.; Rightmire, L. A.
Data from the EUV Imaging Spectrometer on Hinode taken on 2007 May 1 (May Day) are used to investigate the thermal properties of a coronal loop in AR 10953. For background subtraction, we have taken cuts across the loop near the apex and the footpoint where the background is relatively simple. Three density-sensitive line ratios give statistically…
A Survey of 3.3 µm PAH Emission in Planetary Nebulae
McLean, Ian S.; Smith, Erin C. D.
Results are presented from a pilot survey of 3.3 µm PAH emission from planetary nebulae using FLITECAM, an instrument intended for airborne astronomy with SOFIA. The observations were made during ground-based commissioning of FLITECAM's spectroscopic mode at the 3 m Shane Telescope at Lick Observatory. Direct-ruled KRS-5 grisms were used to …
Globular Clusters and X-Ray Point Sources in Centaurus A (NGC 5128)
Jordán, Andrés; Raychaudhury, Somak; Whitaker, Katherine E. +6 more
We detect 353 X-ray point sources, mostly low-mass X-ray binaries (LMXBs), in four Chandra observations of Centaurus A (NGC 5128), the nearest giant early-type galaxy, and correlate this point-source population with the largest available ensemble of confirmed and likely globular clusters (GCs) associated with this galaxy. Of the X-ray sources, 31 …
XMM-Newton Observations of the Nuclei of the Radio Galaxies 3C 305, DA 240, and 4C 73.08
Lee, Julia C.; Kraft, Ralph P.; Birkinshaw, Mark +4 more
We present new XMM-Newton EPIC observations of the nuclei of the nearby radio galaxies 3C 305, DA 240, and 4C 73.08, and investigate the origin of their nuclear X-ray emission. The nuclei of the three sources appear to have different relative contributions of accretion- and jet-related X-ray emission, as expected based on earlier work. The X-ray s…
A Multiwavelength Analysis of the Halo Planetary Nebula DdDm-1
Dufour, R. J.; Henry, R. B. C.; Kwitter, K. B. +1 more
We present new HST optical imagery as well as new UV and IR spectroscopic data obtained with the Hubble Space Telescope and Spitzer Space Telescope, respectively, of the halo planetary nebula DdDm-1. For the first time we present a resolved image of this object, which indicates that the morphology of DdDm-1 can be described as two orthogonal ellip…
Ion Anisotropy and High-Energy Variability of Large Solar Particle Events: A Comparative Study
Reames, Donald V.; Tan, Lun C.; Ng, Chee K.
We have made comparative studies of ion anisotropy and high-energy variability of solar energetic particle (SEP) events previously examined by the Solar, Heliospheric, and Interplanetary Environment (SHINE) Workshop campaign. We have found distinctly different characteristics of SEPs in two large "gradual" events having very similar solar progenit…
Sequestration of Noble Gases by H+3 in Protoplanetary Disks and Outer Solar System Composition
Ceccarelli, C.; Mousis, O.; Pauzat, F. +1 more
We study the efficiency of the noble gas sequestration by the ion H+3 in the form of X H+3 complexes (with X = argon , krypton, or xenon) in gas-phase conditions similar to those encountered during the cooling of protoplanetary disks. We show that X H+3 complexes form very stable st…
The Nearby and Extremely Metal-poor Galaxy CGCG 269-049
Windhorst, Rogier A.; Kim, Hwihyun; Jansen, Rolf A. +2 more
We present Hubble Space Telescope (HST) and Spitzer Space Telescope images and photometry of the extremely metal-poor (Zcong 0.03 Z⊙) blue dwarf galaxy CGCG 269-049. The HST images reveal a large population of red giant and asymptotic giant branch stars, ruling out the possibility that the galaxy has recently formed. From the magnitude …