Search Publications
Cometary ion instabilities in the solar wind
Hellinger, P.; Matteini, L.; Schwartz, S. J.
We review some of the processes that characterize the interaction of the solar wind with newborn cometary ions. Instabilities generated by the typical ring-beam velocity-space configuration of the pick-up ions in the solar wind frame are studied by means of one- and two-dimensional hybrid numerical simulations. In agreement with previous studies, …
The VMC Survey. XVIII. Radial Dependence of the Low-mass, 0.55--0.82 M Stellar Mass Function in the Galactic Globular Cluster 47 Tucanae
Piatti, Andrés E.; Deng, Licai; de Grijs, Richard +12 more
We use near-infrared observations obtained as part of the Visible and Infrared Survey Telescope for Astronomy (VISTA) Survey of the Magellanic Clouds (VMC), as well as two complementary Hubble Space Telescope (HST) data sets, to study the luminosity and mass functions (MFs) as a function of clustercentric radius of the main-sequence stars in the G…
Molecular gas and nuclear activity in early-type galaxies: any link with radio loudness?
Kuno, Nario; Capetti, Alessandro; Baldi, Ranieri D. +4 more
Aims: We want to study the amount of molecular gas in a sample of nearby early-type galaxies (ETGs) that host low-luminosity active galactic nuclei (AGN). We look for possible differences between the radio-loud (RL) and radio-quiet (RQ) AGN.
Methods: We observed the CO(1-0) and CO(2-1) spectral lines with the IRAM 30 m and NRO 45 m teles…
The XMM Deep Survey in the CDF-S. VII. UV catalogue of the Optical Monitor observations
Talavera, A.; Vignali, C.; Ranalli, P. +5 more
Context. The XMM-Newton X-ray observatory has repeatedly observed the Chandra Deep Field-South (CDF-S) in 33 epochs (2001-2010) through the XMM-CDFS Deep Survey. During the X-ray observations, XMM-OM targeted the central 17 × 17 arcmin2 region of the X-ray field of view, providing simultaneous optical/UV coverage of the CDF-S. The resul…
COLDz: Karl G. Jansky Very Large Array Discovery of a Gas-rich Galaxy in COSMOS
Smail, I.; Daddi, E.; Ivison, R. J. +15 more
The broad spectral bandwidth at millimeter and centimeter wavelengths provided by the recent upgrades to the Karl G. Jansky Very Large Array (VLA) has made it possible to conduct unbiased searches for molecular CO line emission at redshifts, z > 1.31. We present the discovery of a gas-rich, star-forming galaxy at z = 2.48 through the detection …
An Extreme Gravitationally Redshifted Iron Line at 4.8 keV in Mrk 876
Greiner, Jochen; Ajello, Marco; Bottacini, Eugenio +3 more
X-ray spectral lines at unforeseen energies are important because they can shed light on the extreme physical conditions of the environment around the supermassive black holes of active galactic nuclei (AGNs). Mrk 876 displays such a line at 4.80+0.05-0.04 rest-frame energy. A possible interpretation of its origin can be foun…
Substorm Current Wedge at Earth and Mercury
Glassmeier, K. -H.; Slavin, J. A.; Kepko, L. +1 more
This chapter reviews magnetospheric substorms and dipolarizations observed at both Earth and Mercury. It briefly discusses new insights into the physics of the substorm current wedge (SCW) that have been revealed the past few years. The formation and evolution of the SCW are closely tied to the braking of flows convecting flux away from the reconn…
Systematic design methods of robust and structured controllers for satellites. Application to the refinement of Rosetta's orbit controller
Falcoz, Alexandre; Pittet, Christelle; Bennani, Samir +3 more
In this paper, the capability of nonsmooth optimisation techniques to solve complex control problems with implementation issues is addressed. {H}_{∞}/ µ design methods are analysed to enhance the current Airbus Defence and Space industrial development process. In the first instance, a reference µ-synthesis controller that achieves the …
What can Gaia (with Thirty Meter Telescope) say about the Sculptor Dwarf's Core?
Evslin, Jarah
Walker et al.'s Magellan/Michigan/MIKE Fiber System (MMFS) survey identified 1355 red giant candidates in the dwarf spheroidal galaxy Sculptor. We find that the Gaia satellite will be able to measure the proper motions of 139 of these with a precision of between 13 and 20 km s-1. Using a Jeans analysis and 5-parameter density model we s…
Mid-infrared variations of R Coronae Borealis stars
Rao, N. Kameswara; Lambert, David L.
Mid-infrared (IR) photometry of R Coronae Borealis stars obtained from various satellites from Infrared Astronomical Satellite (IRAS) to Wide-field Infrared Survey Explorer (WISE) has been utilized in studying the variations of the circumstellar dust's contributions to the spectral energy distribution of these stars. The variation of the fractiona…