Search Publications
Planetary nebulae abundances and stellar evolution II
Pottasch, S. R.; Bernard-Salas, J.
Context. In recent years mid- and far infrared spectra of planetary nebulae have been analysed and lead to more accurate abundances. It may be expected that these better abundances lead to a better understanding of the evolution of these objects.
Aims: The observed abundances in planetary nebulae are compared to those predicted by the models …
MACS J1423.8+2404: gravitational lensing by a massive, relaxed cluster of galaxies at z = 0.54
Kneib, J. -P.; Smith, G. P.; Schrabback, T. +8 more
We present results of a gravitational lensing and optical study of MACS J1423.8+2404 (z = 0.545, MACS J1423), the most relaxed cluster in the high-redshift subsample of clusters discovered in the MAssive Cluster Survey (MACS). Our analysis uses high-resolution images taken with the Hubble Space Telescope in the F555W and F814W passbands, ground-ba…
A Galactic Origin for HE 0437-5439, The Hypervelocity Star Near the Large Magellanic Cloud
Anderson, Jay; Livio, Mario; Bond, Howard E. +4 more
We use Hubble Space Telescope imaging to measure the absolute proper motion of the hypervelocity star (HVS) HE 0437-5439, a short-lived B star located in the direction of the Large Magellanic Cloud (LMC). We observe (µα, µδ) = (+0.53 ± 0.25(stat) ± 0.33(sys), + 0.09 ± 0.21(stat) ± 0.48(sys)) mas yr-1. T…
Doppler-shift, Intensity, and Density Oscillations Observed with the Extreme Ultraviolet Imaging Spectrometer on Hinode
Muglach, K.; Mariska, John T.
Low-amplitude Doppler-shift oscillations have been observed in coronal emission lines in a number of active regions with the EUV Imaging Spectrometer (EIS) on the Hinode satellite. Both standing and propagating waves have been detected and many periods have been observed, but a clear picture of all the wave modes that might be associated with acti…
Submillimeter Array Identification of the Millimeter-selected Galaxy SSA22-AzTEC1: A Protoquasar in a Protocluster?
Yun, M. S.; Lehmer, B. D.; Alexander, D. M. +19 more
We present results from Submillimeter Array (SMA) 860 µm subarcsecond astrometry and multiwavelength observations of the brightest millimeter (S 1.1mm = 8.4 mJy) source, SSA22-AzTEC1, found near the core of the SSA22 protocluster that is traced by Lyα-emitting galaxies at z = 3.09. We identify a 860 µm counterpart with a flu…
Formation, erosion and exposure of Early Amazonian dikes, dike swarms and possible subglacial eruptions in the Elysium Rise/Utopia Basin Region, Mars
Head, J. W.; Wilson, L.; Pedersen, G. B. M.
Hundreds of narrow, linear ridge segments are found in the transition zone between the Elysium Rise and the Utopia basin, occurring as both single and multiple ridges. The ridges are distinctive because of their very linear, steep-sided nature, their often sharp ridge crest (which sometimes is fractured), their association with stubby flows, their…
The AGN, Star-forming, and Morphological Properties of Luminous IR-bright/optically-faint Galaxies
Alexander, D. M.; Egami, E.; Rieke, G. H. +2 more
We present the active galactic nucleus (AGN), star-forming, and morphological properties of a sample of 13 MIR-luminous (f 24 >~ 700 µJy) IR-bright/optically-faint galaxies (IRBGs, f 24/f R >~ 1000). While these z ~ 2 sources were drawn from deep Chandra fields with >200 ks X-ray coverage, only seven…
Non-force-free extrapolation of solar coronal magnetic field using vector magnetograms
Gary, G. A.; Hu, Qiang; Büchner, J. +2 more
We report our recent improvement in non-force-free extrapolation of coronal magnetic field, using vector magnetograms. Based on the principle of minimum (energy) dissipation rate (MDR), a generally non-force-free magnetic field solution is expressed as the superposition of one potential field and two (constant-[alpha]) linear force-free fields, wi…
The nature of p-modes and granulation in HD 49933 observed by CoRoT
Fossati, L.; Kallinger, T.; Guenther, D. B. +2 more
Context. Recent observations of HD 49933 by the space-photometric mission CoRoT provide photometric evidence of solar type oscillations in a star other than our Sun. The first published reduction, analysis, and interpretation of the CoRoT data yielded a spectrum of p-modes with l = 0, 1, and 2.
Aims: We present our own analysis of the CoRoT d…
Cluster Active Archive: Overview
Escoubet, C. P.; Taylor, M. G. G. T.; Laakso, H. +7 more
The four-satellite Cluster mission investigates the small-scale structures and physical processes related to interaction between the solar wind and the magnetospheric plasma. The Cluster Active Archive (CAA) (URL: http://caa.estec.esa.int) will contain the entire set of Cluster high-resolution data and other allied products in a standard format an…