Search Publications
Suzaku Observations of the Dwarf Nova V893 Scorpii: The Discovery of a Partial X-ray Eclipse
Mukai, K.; Still, M.; Zietsman, E.
V893 Sco is an eclipsing dwarf nova that had attracted little attention from X-ray astronomers until it was proposed as the identification of an Rossi X-Ray Timing Explorer all-sky slew survey (XSS) source. Here, we report on the pointed X-ray observations of this object using Suzaku. V893 Sco was in quiescence at the time, as indicated by the coo…
Properties of the ionised plasma in the vicinity of the neutron-star X-ray binary EXO 0748-676
Costantini, E.; Méndez, M.; Paerels, F. B. S. +2 more
Aims: We present the spectral analysis of a large set of XMM-Newton observations of EXO 0748-676, a bright dipping low-mass X-ray binary. In particular, we focus on the dipping phenomenon as a result of changes in the properties of the ionised gas close to the source.
Methods: We analysed the high-resolution spectra collected with the reflecti…
Analysis of Dark Albedo Features on a Southern Polar Dune Field of Mars
Kereszturi, Ákos; Horváth, András; Bérczi, Szaniszló +4 more
We observed 20-200 m sized low-albedo seepage-like streaks and their annual change on defrosting polar dunes in the southern hemisphere of Mars, based on the Mars Orbiter Camera (MOC), High Resolution Stereo Camera (HRSC), and High Resolution Imaging Science Experiment (HiRISE) images. The structures originate from dark spots and can be described …
Suzaku Observations of Thermal and Non-Thermal X-Ray Emission from the Middle-Aged Supernova Remnant G156.2+5.7
Katsuda, Satoru; Petre, Robert; Yamaguchi, Hiroya +3 more
We present results from an X-ray analysis of a Galactic middle-aged supernova remnant (SNR), G156.2+5.7, which is bright and largely extended in X-ray wavelengths, showing a clear circular shape (radius ∼50'). Using the Suzaku satellite, we observed this SNR in three pointings: partially covering the northwestern rim, the eastern rim, and the cent…
Plasma environment at Titan's orbit with Titan present and absent
Coates, A. J.; Russell, C. T.; Wei, H. Y. +2 more
To understand the possible large scale influence of Titan on its plasma environment, we study the magnetic fields and plasma measurements, both when Cassini flies close to Titan and when Cassini crosses the moon's orbit far from it. Using 98 Cassini passes from 06/2004 to 12/2008, we examine the plasma environments at the orbit of Titan with the m…
Imaging the Cool Hypergiant NML Cygni's Dusty Circumstellar Envelope with Adaptive Optics
Humphreys, R. M.; Schuster, M. T.; Fazio, G. G. +6 more
We present subarcsecond angular resolution, high-Strehl ratio mid-IR adaptive optics images of the powerful OH/IR source and cool hypergiant NML Cyg at 8.8, 9.8, and 11.7 µm. These images reveal once more the complexity in the dusty envelope surrounding this star. We spatially resolve the physical structures (radius ~ 0farcs14, ~240 AU adopt…
Suzaku Observation of the Giant Radio Galaxy 3C 326
Isobe, Naoki; Gandhi, Poshak; Tashiro, Makoto S. +5 more
A Suzaku observation of a giant radio galaxy, 3C 326, which has a physical size of about 2 Mpc, was conducted on 2008 January 19-21. In addition to several X-ray sources, diffuse emission was significantly detected and associated with its west lobe, but the east lobe was contaminated by an unidentified X-ray source WARP J1552.4+2007. After careful…
Response of Saturn's ionosphere to solar radiation: Testing parameterizations for thermal electron heating and secondary ionization processes
Galand, Marina; Moore, Luke; Mendillo, Michael +1 more
We evaluate the effectiveness of two parameterizations in Saturn's ionosphere over a range of solar fluxes, seasons, and latitudes. First, the parameterization of the thermal electron heating rate, Q* e, introduced in [Moore, L., Galand, M., Mueller-Wodarg, I., Yelle, R.V., Mendillo, M., 2008. Plasma temperatures in Saturn's ionosphere.…
Interstellar Dust Inside and Outside the Heliosphere
Krüger, Harald; Grün, Eberhard
In the early 1990s, after its Jupiter flyby, the Ulysses spacecraft identified interstellar dust in the solar system. Since then the in-situ dust detector on board Ulysses continuously monitored interstellar grains with masses up to 10-13 kg, penetrating deep into the solar system. While Ulysses measured the interstellar dust stream at …
Lithium and magnetic fields in giant stars. HD 232 862: a magnetic and lithium-rich giant
de Laverny, P.; de Medeiros, J. R.; Palacios, A. +5 more
Aims: We report the detection of an unusually high lithium content in HD 232 862, a field giant classified as a G8II star, and hosting a magnetic field.
Methods: With the spectropolarimeters ESPaDOnS at CFHT and NARVAL at TBL, we collected high resolution and high signal-to-noise spectra of three giants: HD 232 862, KU Peg and HD 21 018. From …