Search Publications
Kinematics and stellar population of NGC 4486A
Prugniel, Ph.; Zeilinger, W.; Koleva, M. +1 more
Context. NGC 4486A is a low-luminosity elliptical galaxy harbouring an edge-on nuclear disk of stars and dust. It is known to host a super-massive black hole.
Aims: We study its large-scale kinematics and stellar population along the major axis to investigate the link between the nuclear and global properties.
Methods: We use long-slit m…
Local helioseismology of sunspot regions: Comparison of ring-diagram and time-distance results
Kosovichev, A. G.; Howe, R.; Komm, R. +10 more
Local helioseismology provides unique information about the subsurface structure and dynamics of sunspots and active regions. However, because of complexity of sunspot regions local helioseismology diagnostics require careful analysis of systematic uncertainties and physical interpretation of the inversion results. We present new results of compar…
The transmission of upstream waves to the magnetosphere: An analysis at widely separated ground stations
Francia, P.; Villante, U.; De Paulis, C.
On 18 February 2003 a long-duration, almost monochromatic, wave event was detected by Cluster at radial distances from the bow shock smaller than ≈10 Re. The interplanetary magnetic field orientation determined a wide and almost symmetric foreshock region around the bow shock nose, providing highly favorable conditions for a direct wave penetratio…
The X-ray emission of the colliding wind binary V444 Cyg
Nazé, Yaël; De Becker, Michaël; Fauchez, Thomas
This paper presents the analysis of six XMM-Newton observations of the colliding wind system V444 Cyg. Unlike what one might have expected at first, it appears that the O star wind most probably dominates the WN wind: the bow shock is wide open, with the hard X-ray emission arising close to the WN star. An important radiative braking could partly …
The morphology-density relation of galaxies around MACS J0717.5+3745
Ebeling, H.; Ma, C. -J.
We use an 18 × 9 arcmin2 mosaic of HST/ACS images covering the entire large-scale structure around the X-ray luminous cluster MACSJ0717.5+3745 (z= 0.545) to study the morphology of galaxies at the cluster redshift. We find the global fraction of morphological types of galaxies to be consistent with results in the literature. In addition…
Nature of the Unidentified TeV Source HESS J1614-518, Revealed by Suzaku and XMM-Newton Observations
Matsumoto, Hironori; Sakai, Michito; Yajima, Yukie
We report on new Suzaku and XMM-Newton results concerning HESS J1614
The nature of the Na I D-lines in the Red Rectangle
York, Donald G.; Bjorkman, J. E.; Federman, S. R. +6 more
In this paper we examine the profiles of the complex Na I D-lines in the Red Rectangle. The spectra were acquired with the Astrophysical Research Consortium Echelle Spectrograph (ARCES) echelle spectrograph (R= 38 000) on the 3.5-m telescope at the Apache Point Observatory. Additional spectra taken with Space Telescope Imaging Spectrograph were ac…
Transition Region Emission from Solar Flares during the Impulsive Phase
Raymond, J. C.; Ciaravella, A.; Giordano, S. +4 more
There are relatively few observations of UV emission during the impulsive phases of solar flares, so the nature of that emission is poorly known. Photons produced by solar flares can resonantly scatter off atoms and ions in the corona. Based on off-limb measurements by the Solar and Heliospheric Observatory/Ultraviolet Coronagraph Spectrometer, we…
A powerful tool for browsing quick-look data in solar-terrestrial physics: "Conjunction Event Finder"
Shinohara, Iku; Hasegawa, Hiroshi; Fujimoto, Masaki +4 more
The "Conjunction Event Finder (CEF)" is a Web tool for seamlessly browsing quick-look (QL) data from many different kinds of satellites and ground-based instruments in solar-terrestrial physics. The QL plots are generally scattered all over the world, so that browsing many of them is so far very troublesome and inefficient. Just a simple procedure…
A New Method of Dark-Current Estimation for Diffuse Sky Measurements with the AKARI Infrared Camera
Wada, Takehiko; Tsumura, Kohji
We developed a new method for estimating the dark current of near-infrared (NIR) data from the Infra-Red Camera (IRC) aboard the AKARI satellite. The existing method of dark-current estimation is insufficient because the dark current is enhanced by charged particles hitting the detector in the South Atlantic Anomaly (SAA). We could trace this dark…