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Near-infrared spectroscopy of (proto)-planetary nebulae: molecular hydrogen excitation as an evolutionary tracer
Smith, Michael D.; Davis, Christopher J.; Stern, Luke +2 more
We present an in-depth analysis of molecular excitation in 11 H2-bright planetary and protoplanetary nebulae (PN and PPN). From newly acquired K-band observations, we extract a number of spectra at positions across each source. H2 line intensities are plotted on `column density ratio' diagrams so that we may examine the excit…
On the kinematic evolution of flare-associated cmes
Moon, Y. -J.; Shanmugaraju, A.; Dryer, M. +1 more
We report a common tendency of the kinematic evolution of three flare-associated coronal mass ejections (CMEs). Their kinematic evolutions are examined using well-observed data (eruptive filaments, X-ray structures, and prominences) very close to the solar surface as well as SOHO/LASCO C2-C3 data. Their height-time data are fitted using three anal…
GaBoDS: The Garching-Bonn Deep Survey. I. Anatomy of galaxy clusters in the background of NGC 300
Schirmer, M.; Micol, A.; Schneider, P. +5 more
The Garching-Bonn Deep Survey (GaBoDS) is a virtual 12 square degree cosmic shear and cluster lensing survey, conducted with the WFI@2.2 m MPG/ESO telescope at La Silla. It consists of shallow, medium and deep random fields taken in R-band in subarcsecond seeing conditions at high galactic latitude. A substantial amount of the data was taken from …
Perpendicular Transport of Solar Energetic Particles in Heliospheric Magnetic Fields
McKibben, R. B.; Zhang, Ming; Jokipii, J. R.
This paper presents direct observational evidence for large perpendicular diffusive flows of solar energetic particles in heliospheric magnetic fields. Using anisotropy measurements of 40-92 MeV protons obtained by the High-Energy Telescope of the COSPIN consortium on Ulysses at high heliographic latitudes, we find that during several gradual sola…
Simulation of energetic particle injections associated with a substorm on August 27, 2001
Baker, D. N.; Sarris, T. E.; Peterson, W. K. +2 more
Discrete injections of energetic electrons and ions and their subsequent drift echoes were observed shortly after 0410 UT on August 27, 2001 by three geosynchronous satellites which were arrayed on the dayside. The GOES-8 spacecraft at geosynchronous orbit near local midnight, the four-satellite CLUSTER constellation also near local midnight. Conc…
RR Lyrae stars in four globular clusters in the Fornax dwarf galaxy
Mackey, A. D.; Gilmore, G. F.
We have surveyed four of the globular clusters in the Fornax dwarf galaxy (clusters 1, 2, 3 and 5) for RR Lyrae stars, using archival F555W and F814W Hubble Space Telescope observations. We identify 197 new RR Lyrae stars in these four clusters, and 13 additional candidate horizontal-branch variable stars. Although somewhat restricted by our short…
Disentangling microlensing and differential extinction in the double QSO HE 0512-3329
Lopez, S.; Wisotzki, L.; Wucknitz, O. +1 more
We present the first separate spectra of both components of the small-separation double QSO
Hot Gas in the Circumstellar Bubble S308
Guerrero, Martín A.; Chu, You-Hua; Gruendl, Robert A. +2 more
S308 is a circumstellar bubble blown by the WN4 star HD 50896. It is one of the only two single-star bubbles that show detectable diffuse X-ray emission. We have obtained XMM-Newton EPIC observations of the northwest quadrant of S308. The diffuse X-ray emission shows a limb-brightened morphology, with a clear gap extending from the outer edge of t…
Hubble Space Telescope observations of globular cluster systems along the Hubble sequence of spiral galaxies
Strader, Jay; Minniti, Dante; Kissler-Patig, Markus +3 more
We have studied the globular cluster systems of seven giant, edge-on spiral galaxies using Hubble Space Telescope imaging in V and I. The galaxy sample covers the Hubble types Sa to Sc, allowing us to study the variation of the properties of globular cluster systems along the Hubble sequence. The photometry reaches ~1.5 mag beyond the turn-over ma…
Evidence for an Intermediate-Age, Metal-rich Population of Globular Clusters in NGC 4365
Forbes, Duncan A.; Brodie, Jean P.; Beasley, Michael A. +4 more
We present spectroscopy for globular clusters (GCs) in the elliptical galaxy NGC 4365, obtained with the Low-Resolution Imaging Spectrograph on the Keck I telescope. Previous studies have shown that the optical color distribution of GCs in NGC 4365 lacks the bimodal structure that is common in globular cluster systems, showing only a single broad …