Search Publications
The galaxy major merger fraction to {z} 1
Pérez-González, P. G.; López-Sanjuan, C.; Gallego, J. +4 more
Aims: The importance of disc-disc major mergers in galaxy evolution remains uncertain. We study the major merger fraction in a SPITZER/IRAC-selected catalogue in the GOODS-S field up to z 1 for luminosity- and mass-limited samples.
Methods: We select disc-disc merger remnants on the basis of morphological asymmetries/distortions, and address t…
Multispacecraft Observations of Magnetic Clouds and Their Solar Origins between 19 and 23 May 2007
Liu, Y.; Luhmann, J. G.; Russell, C. T. +11 more
We analyze a series of complex interplanetary events and their solar origins that occurred between 19 and 23 May 2007 using observations by the STEREO and Wind satellites. The analyses demonstrate the new opportunities offered by the STEREO multispacecraft configuration for diagnosing the structure of in situ events and relating them to their sola…
The SAURON Project - XIV. No escape from Vesc: a global and local parameter in early-type galaxy evolution
Krajnović, Davor; Emsellem, Eric; van de Ven, Glenn +13 more
We present the results of an investigation of the local escape velocity (Vesc) - line strength index relationship for 48 early-type galaxies from the SAURON sample, the first such study based on a large sample of galaxies with both detailed integral field observations and extensive dynamical modelling. Values of Vesc are comp…
Altitude of Saturn's aurora and its implications for the characteristic energy of precipitated electrons
Bonfond, B.; Clarke, J. T.; Gérard, J. -C. +4 more
Images of Saturn's aurora at the limb have been collected with the Advanced Camera for Surveys on board the Hubble Space Telescope. They show that the peak of Saturn's nightside emission is generally located 900-1300 km above the 1-bar level. On the other hand, methane and H2 columns overlying the aurora have been determined from the an…
The solar chromosphere at high resolution with IBIS. II. Acoustic shocks in the quiet internetwork and the role of magnetic fields
Vecchio, A.; Cauzzi, G.; Reardon, K. P.
Context: The exact nature of the quiet solar chromosphere and especially its temporal variation, are still subjects of intense debate. One of the contentious issues is the possible role of the magnetic field in structuring the quieter solar regions.
Aims: We characterize the dynamics of the quiet inter-network chromosphere by studying the occu…
A single sub-kilometre Kuiper belt object from a stellar occultation in archival data
Zucker, S.; Gal-Yam, A.; Sari, R. +5 more
The Kuiper belt is a remnant of the primordial Solar System. Measurements of its size distribution constrain its accretion and collisional history, and the importance of material strength of Kuiper belt objects. Small, sub-kilometre-sized, Kuiper belt objects elude direct detection, but the signature of their occultations of background stars shoul…
Multiwavelength Observations of 3C 454.3. I. The AGILE 2007 November campaign on the "Crazy Diamond"
Costa, E.; Mereghetti, S.; Chen, W. P. +68 more
We report on a multiwavelength observation of the blazar 3C 454.3 (which we dubbed crazy diamond) carried out on November 2007 by means of the astrophysical satellites AGILE, International Gamma-Ray Astrophysics Laboratory (INTEGRAL), Swift, the Whole Earth Blazar Telescope (WEBT) Consortium, and the optical-NIR telescope Rapid Eye Mount (REM). Th…
The Incidence of Active Galactic Nuclei in Pure Disk Galaxies: The Spitzer View
Abel, N. P.; Böker, T.; Satyapal, S. +3 more
Using the Spitzer telescope, we have conducted a high-resolution spectroscopic study of 18 bulgeless (Hubble type of Sd or Sdm) galaxies that show no definitive signatures of nuclear activity in their optical spectra. This is the first systematic mid-infrared (MIR) search for weak or hidden active galactic nuclei (AGNs) in a statistically signific…
Prominence Formation Associated with an Emerging Helical Flux Rope
Shibata, Kazunari; Tsuneta, Saku; Shimizu, Toshifumi +12 more
The formation and evolution process and magnetic configuration of solar prominences remain unclear. In order to study the formation process of prominences, we examine continuous observations of a prominence in NOAA AR 10953 with the Solar Optical Telescope on the Hinode satellite. As reported in our previous Letter, we find a signature suggesting …
X-ray evidence for a mildly relativistic and variable outflow in the luminous Seyfert 1 galaxy Mrk 509
Maraschi, L.; Bianchi, S.; Cappi, M. +9 more
Context: There is growing evidence for the presence of blueshifted Fe K absorption lines in a number of radio-quiet AGNs and QSOs. These may be fundamental to probe flow dynamics near supermassive black holes.
Aims: Here we aim to verify and better characterise the existence of such Fe K absorption at ~8-10 keV in the luminous Seyfert 1 galaxy…