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Searching for Faraday rotation in cosmic microwave background polarization
Battaner, E.; Ruiz-Granados, B.; Florido, E.
We use the Wilkinson Microwave Anisotropy Probe (WMAP) 9th-year foreground reduced data at 33, 41 and 61 GHz to derive a Faraday rotation at map and at angular power spectrum levels taking into account their observational errors. A processing mask provided by WMAP is used to avoid contamination from the disc of our Galaxy and local spurs. We have …
Doppler Shift of the Quiet Region Measured by Meridional Scans with the EUV Imaging Spectrometer on board Hinode
Hara, H.; Kitagawa, N.; Yokoyama, T.
Spatially averaged (> 50") EUV spectral lines in the transition region of solar quiet regions are known to be redshifted. Because the mechanism underlying this phenomenon is unclear, we require additional physical information on the lower corona in order to limit the theoretical models. To acquire this information, we measured the Doppler shift…
Variability of the X-ray broad iron spectral features in active galactic nuclei and black-hole binaries
Tsujimoto, M.; Ebisawa, K.; Inoue, H. +1 more
The ``broad iron spectral features'' are often seen in X-ray spectra of active galactic nuclei (AGN) and black-hole binaries (BHB). These features may be explained either by the ``relativistic disc reflection'' scenario or the ``partial covering'' scenario: It is hardly possible to determine which model is valid from time-averaged spectral analysi…
The end-of-life disposal of satellites in libration-point orbits using solar radiation pressure
Soldini, Stefania; Colombo, Camilla; Walker, Scott
This paper proposes an end-of-life propellant-free disposal strategy for libration-point orbits which uses solar radiation pressure to restrict the evolution of the spacecraft motion. The spacecraft is initially disposed into the unstable manifold leaving the libration-point orbit, before a reflective sun-pointing surface is deployed to enhance th…
Suzaku confirms NGC 3660 is an unabsorbed Seyfert 2
Nandra, Kirpal; Ueda, Yoshihiro; Bianchi, Stefano +3 more
An enigmatic group of objects, unabsorbed Seyfert 2s may have intrinsically weak broad line regions, obscuration in the line of sight to the BLR but not to the X-ray corona, or so much obscuration that the X-ray continuum is completely suppressed and the observed spectrum is actually scattered into the line of sight from nearby material. NGC 3660 …
Critical pitch angle for electron acceleration in a collisionless shock layer
Narita, Y.; Motschmann, U.; Comişel, H.
Collisionless shock waves in space and astrophysical plasmas can accelerate electrons along the shock layer by an electrostatic potential, and scatter or reflect electrons back to the upstream region by the amplified magnetic field or turbulent fluctuations. The notion of the critical pitch angle is introduced for non-adiabatic electron accelerati…
Prometheus Induced Vorticity in Saturn's F Ring
Sutton, Phil J.; Kusmartsev, Feo V.
Saturn's rings are known to show remarkable real time variability in their structure. Many of which can be associated to interactions with nearby moons and moonlets. Possibly the most interesting and dynamic place in the rings, probably in the whole Solar System, is the F ring. A highly disrupted ring with large asymmetries both radially and azimu…
The shape of Saturn's Huygens ringlet viewed by Cassini ISS
Spitale, J. N.; Hahn, J. M.
A new model for the shape of the prominent eccentric ringlet in the gap exterior to Saturn's B ring is developed based on Cassini imaging observations taken over about 8 years. Unlike previous analyses, the new model treats each edge of the ringlet separately. The Keplerian component of the model is consistent with results derived from Voyager obs…
Ultraviolet spectral variations of symbiotic nova PU Vul during and after second eclipse
Sanad, M. R.
I have analyzed spectral data of the symbiotic nova PU Vul observed with the International Ultraviolet Explorer (IUE) during the period 1993–1996. The study concentrated on the two sources of nebular emitting regions, the first is a nebula around the white dwarf partially eclipsed by a cool giant star and the second is a very extended nebular regi…
The orbital phase resolved spectroscopy of X-ray binary 4U 1822-371 with Suzaku
Ji, Li; Nowak, Michael A.; Schulz, Norbert S. +3 more
4U 1822-371 is a typical edge-on eclipsing low mass X-ray binary and the prototype of accretion disk coronal sources. We report on the results of a spectral analysis over the energy range 0.5-45 keV observed by Suzaku in 2006. We extract spectra from five orbital phases. The spectra can be equally well described by various previously proposed mode…