Search Publications
Search for the Infrared Emission Features from Deuterated Interstellar Polycyclic Aromatic Hydrocarbons
Onaka, Takashi; Sakon, Itsuki; Kaneda, Hidehiro +4 more
We report the results of a search for emission features from interstellar deuterated polycyclic aromatic hydrocarbons (PAHs) in the 4 µm region with the Infrared Camera (IRC) on board AKARI. No significant excess emission is seen in 4.3-4.7 µm in the spectra toward the Orion Bar and M17 after the subtraction of line emission from the i…
Atomic data for astrophysics: Fe IX
Mason, H. E.; Del Zanna, G.; Storey, P. J. +1 more
We present the results of a new large-scale intermediate-coupling frame transformation R-matrix scattering calculation for electron collisional excitation of Fe ix. The target includes all the main configurations up to n = 5, to improve our earlier R-matrix and distorted-wave (DW) calculations for the n = 3,4 levels. Unlike similar calculations wh…
Multiwavelength observation of a large-scale flux rope eruption above a kinked small filament
Kumar, Pankaj; Cho, Kyung-Suk
We analyzed multiwavelength observations of a western limb flare (C3.9) that occurred in AR NOAA 111465 on 30 April 2012. The high-resolution images recorded by SDO/AIA 304, 1600 Å and Hinode/SOT Hα show the activation of a small filament (rising speed ~40 km s-1) associated with a kink instability and the onset of a C-class flare near …
Landing on small bodies: From the Rosetta Lander to MASCOT and beyond
Ulamec, Stephan; Biele, Jens; Geurts, Koen +9 more
Recent planning for science and exploration missions has emphasized the high interest in the close investigation of small bodies in the Solar System. In particular in-situ observations of asteroids and comets play an important role in this field and will contribute substantially to our understanding of the formation and history of the Solar System…
Charge State Evolution in the Solar Wind. III. Model Comparison with Observations
Lepri, S. T.; Zurbuchen, T. H.; Fisk, L. A. +3 more
We test three theoretical models of the fast solar wind with a set of remote sensing observations and in-situ measurements taken during the minimum of solar cycle 23. First, the model electron density and temperature are compared to SOHO/SUMER spectroscopic measurements. Second, the model electron density, temperature, and wind speed are used to p…
The Snapshot Hubble U-Band Cluster Survey (SHUCS). II. The Star Cluster Population of NGC 2997
Larsen, S.; Bastian, N.; Smith, L. J. +6 more
We study the star cluster population of NGC 2997, a giant spiral galaxy located at 9.5 Mpc and targeted by the Snapshot Hubble U-band Cluster Survey (SHUCS). Combining our U-band imaging from SHUCS with archival BVI imaging from the Hubble Space Telescope, we select a high confidence sample of clusters in the circumnuclear ring and disk through a …
Stardust Interstellar Preliminary Examination X: Impact speeds and directions of interstellar grains on the Stardust dust collector
Postberg, Frank; Altobelli, Nicolas; Trieloff, Mario +65 more
On the basis of an interstellar dust model compatible with Ulysses and Galileo observations, we calculate and predict the trajectories of interstellar dust (ISD) in the solar system and the distribution of the impact speeds, directions, and flux of ISD particles on the Stardust Interstellar Dust Collector during the two collection periods of the m…
Geometry, stratigraphy and evidences for fluid expulsion within Crommelin crater deposits, Arabia Terra, Mars
Rossi, A. P.; Pondrelli, M.; Franchi, F. +1 more
Conical mounds and furrows are widely interpreted as the morphological evidences of fluids expulsion on the martian surface. In the Crommelin crater (equatorial Arabia Terra) furrows and conical mounds are exhumed within light-toned equatorial layered deposits (ELDs). Aim of this paper is to describe these landforms and discuss their potential rel…
Constraining the Age of the NGC 4565 H I Disk Warp: Determining the Origin of Gas Warps
Bell, Eric F.; Holwerda, Benne W.; Monachesi, Antonela +7 more
We have mapped the distribution of young and old stars in the gaseous H I warp of NGC 4565. We find a clear correlation of young stars (<600 Myr) with the warp but no coincident old stars (>1 Gyr), which places an upper limit on the age of the structure. The formation rate of the young stars, which increased ~300 Myr ago relative to the surr…
Discovery of a Gas-rich Companion to the Extremely Metal-poor Galaxy DDO 68
Bailin, Jeremy; McQuinn, Kristen B. W.; Cannon, John M. +17 more
We present H I spectral-line imaging of the extremely metal-poor galaxy DDO 68. This system has a nebular oxygen abundance of only ~3% Z ⊙, making it one of the most metal-deficient galaxies known in the local volume. Surprisingly, DDO 68 is a relatively massive and luminous galaxy for its metal content, making it a significant outlier …