Search Publications
Missions
Journals
Publication Years
Newly Identified Star Clusters in M33. I. Integrated Photometry and Color-Magnitude Diagrams
Sarajedini, Ata; Schommer, Robert; Barker, M. K. +2 more
We present integrated photometry and color-magnitude diagrams (CMDs) for 24 star clusters in M33, of which 12 were previously uncataloged. These results are based on Advanced Camera for Surveys observations from the Hubble Space Telescope of two fields in M33. Our integrated V magnitudes and V-I colors for the previously identified objects are in …
The Rosetta Alpha Particle X-Ray Spectrometer (APXS)
Klingelhöfer, G.; Brückner, J.; D'uston, C. +2 more
The Alpha Particle X-Ray Spectrometer (APXS) is a small instrument to determine the elemental composition of a given sample. For the ESA Rosetta mission, the periodical comet 67P/Churyumov-Gerasimenko was selected as the target comet, where the lander PHILAE (after landing) will carry out in-situ observations. One of the instruments onboard is the…
Search for Electron-Positron Annihilation Radiation from the Jet in 3C 120
McHardy, Ian M.; Agudo, Iván; Jorstad, Svetlana G. +3 more
We report an attempt to detect the electron-positron annihilation line from the radio galaxy 3C 120, in which the jet interacts strongly with interstellar clouds. Such interactions should cause most of the jet plasma to mix with the gas in the clouds. This will thermalize the majority of any positrons in the jet, leading to continuous annihilation…
Internal structure of a magnetic flux rope from Cluster observations
Zong, Q. -G.; Kistler, L. M.; Dunlop, M. W. +3 more
We investigate a magnetic flux rope (MFR) observed by Cluster in the magnetotail during a substorm on 2001 August 22. The MFR was aligned with its principal axis closely along the dawn-dusk direction and had a small size of ~2 R E with a total current of ~0.8 MA. The four spacecraft traversed the MFR at different distances from its cent…
Image-Processing Techniques for the Creation of Presentation-Quality Astronomical Images
Levay, Zoltan G.; English, Jayanne; Frattare, Lisa M. +2 more
The quality of modern astronomical data and the agility of current image-processing software enable the visualization of data in a way that exceeds the traditional definition of an astronomical image. Two developments in particular have led to a fundamental change in how astronomical images can be assembled. First, the availability of high-quality…
Near- to Mid-Infrared Spectroscopy for the Giant Elliptical Galaxy NGC 1316 (Fornax A) with the AKARI Infrared Camera
Onaka, T.; Sakon, I.; Kaneda, H.
We present the near- to mid-infrared (~2.5-13 µm) spectrum of the giant elliptical galaxy NGC 1316 (Fornax A) obtained with the Infrared Camera (IRC) on board AKARI. NGC 1316 is known to have a peculiar polycyclic aromatic hydrocarbon (PAH) emission spectrum with an unusually high ratio of the 11.3 µm to the 7.7 µm emission inten…
Determination of the light curve of the Rosetta target asteroid (2867) Steins by the OSIRIS cameras onboard Rosetta
Lamy, P.; Keller, H. U.; Mottola, S. +9 more
Context: In 2004 asteroid (2867) Steins has been selected as a flyby target for the Rosetta mission. Determination of its spin period and the orientation of its rotation axis are essential for optimization of the flyby planning.
Aims: Measurement of the rotation period and light curve of asteroid (2867) Steins at a phase angle larger than achi…
Very Large Array Plus Pie Town Astrometry of 46 Radio Stars
Zacharias, N.; Claussen, M. J.; Johnston, K. J. +4 more
We have used the Very Large Array, linked with the Pie Town Very Long Baseline Array antenna, to determine astrometric positions of 46 radio stars in the International Celestial Reference Frame (ICRF). Positions were obtained in the ICRF directly through phase referencing of the stars to nearby ICRF quasars whose positions are accurate at the 0.25…
Mrk 609 : resolving the circumnuclear structure with near-infrared integral field spectroscopy
Hasinger, G.; Pott, J. -U.; Eckart, A. +5 more
Aims:We present first results of near-infrared (NIR) J and H + K ESO-SINFONI integral field spectroscopy of the composite starburst/Seyfert 1.8 galaxy Mrk 609. The data were taken during the science verification period of SINFONI. We aim to investigate the morphology and excitation conditions within the central 2 kpc. Additional Nobeyama 45 m CO(1…
RHESSI and Hinode X-Ray Observations of a Partially Occulted Solar Flare
Krucker, Säm; Lin, R. P.; Hannah, I. G.
This Letter presents X-ray observations of a partially limb-occulted solar flare taken by the Reuven Ramaty High-Energy Solar Spectroscopic Imager and the X-ray telescope on board Hinode. Thermal emission originates from a simple loop at the western limb that rises slowly (~7 km s-1) until the flare peak time. Above 18 keV, faint nonthe…