Search Publications
Simultaneous XMM-Newton and HST-COS observation of 1H 0419-577. II. Broadband spectral modeling of a variable Seyfert galaxy
Kaastra, J. S.; Costantini, E.; Ebrero, J. +3 more
In this paper, we present the longest exposed (97 ks) XMM-Newton EPIC-pn spectrum ever obtained for the Seyfert 1.5 galaxy1H 0419-577. With the aim of explaining the broadband emission of this source, we took advantage of the simultaneous coverage in the optical/UV that was provided in the present case by the XMM-Newton Optical Monitor and by a HS…
Nanodust detection near 1 AU from spectral analysis of Cassini/Radio and Plasma Wave Science data
Schippers, P.; André, N.; Kurth, W. S. +3 more
Nanodust grains of a few nanometers in size are produced near the Sun by collisional breakup of larger grains and picked up by the magnetized solar wind. They have so far been detected at 1 AU by only the two STEREO spacecraft. Here we analyze the spectra measured by the radio and plasma wave instrument onboard Cassini during the cruise phase clos…
Measurements of Outflow Velocities in on-disk Plumes from EIS/Hinode Observations
Fu, Hui; Li, Bo; Xia, Lidong +3 more
The contribution of plumes to the solar wind has been subject to hot debate in the past decades. The EUV Imaging Spectrometer (EIS) on board Hinode provides a unique means to deduce outflow velocities at coronal heights via direct Doppler shift measurements of coronal emission lines. Such direct Doppler shift measurements were not possible with pr…
Plasma convection in the nightside magnetosphere of Saturn determined from energetic ion anisotropies
Krimigis, S. M.; Mitchell, D. G.; Carbary, J. F. +1 more
The Cassini Ion and Neutral Camera measures intensities of hydrogen and oxygen ions and neutral atoms in the Saturnian magnetosphere and beyond. We use the measured intensity spectrum and anisotropy of energetic hydrogen and oxygen ions to detect, qualify, and quantify plasma convection. We find that the plasma azimuthal convection speed relative …
A Wind Accretion Model for HLX-1
Maccarone, Thomas J.; Farrell, Sean A.; Miller, M. Coleman
The brightest ultraluminous X-ray source currently known, HLX-1, has been observed to undergo five outburst cycles. The periodicity of these outbursts, and their high inferred maximum accretion rates of ~few × 10-4 M ⊙ yr-1, naturally suggest Roche lobe overflow at the pericenter of an eccentric orbit. It is, howev…
Masses of the components of SB2 binaries observed with Gaia - I. Selection of the sample and mass ratios of 20 new SB2s discovered with Sophie
Mazeh, T.; Tal-Or, L.; Halbwachs, J. -L. +7 more
In anticipation of the Gaia astrometric mission, a large sample of spectroscopic binaries has been observed since 2010 with the Sophie spectrograph at the Haute-Provence Observatory. Our aim is to derive the orbital elements of double-lined spectroscopic binaries (SB2s) with an accuracy sufficient finally to obtain the masses of the components wit…
On Magnetic Activity Band Overlap, Interaction, and the Formation of Complex Solar Active Regions
McIntosh, Scott W.; Leamon, Robert J.
Recent work has revealed a phenomenological picture of the how the ~11 yr sunspot cycle of the Sun arises. The production and destruction of sunspots is a consequence of the latitudinal-temporal overlap and interaction of the toroidal magnetic flux systems that belong to the 22 yr magnetic activity cycle and are rooted deep in the Sun's convective…
Small-scale Properties of Atomic Gas in Extended Disks of Galaxies
Bowen, David V.; Tripp, Todd M.; York, Donald G. +4 more
We present high-resolution H I 21 cm observations with the Karl G. Jansky Very Large Array for three H I rich galaxies in absorption against radio quasars. Our sample contains six sightlines with impact parameters from 2.6 to 32.4 kpc. We detected a narrow H I absorber of FWHM 1.1 km s-1 at 444.5 km s-1 toward SDSS J122106.85…
The M 4 Core Project with HST - III. Search for variable stars in the primary field
van den Berg, M.; Anderson, J.; Milone, A. P. +14 more
We present the results of a photometric search for variable stars in the core of the Galactic globular cluster Messier 4 (M 4). The input data are a large and unprecedented set of deep Hubble Space Telescope WFC3 images (large programme GO-12911; 120 orbits allocated), primarily aimed at probing binaries with massive companions by detecting their …
Collisional modelling of the debris disc around HIP 17439
Krivov, A. V.; Eiroa, C.; Löhne, T. +3 more
We present an analysis of the debris disc around the nearby K2 V star HIP 17439. In the context of the Herschel DUNES key programme, the disc was observed and spatially resolved in the far-IR with the Herschel PACS and SPIRE instruments. In a previous study, we assumed that the size and radial distribution of the circumstellar dust are independent…