Search Publications
Benchmarking atomic data for astrophysics: Fe VII and other cool lines observed by Hinode EIS
Del Zanna, G.
The EUV spectrum of ion{Fe}{vii} is reviewed, using new rates for electron impact excitation, atomic structure calculations, and experimental data. In particular, solar observations of a sunspot loop spectrum obtained from the Hinode EUV Imaging Spectrometer (EIS) are used. Previous line identifications, mostly based on laboratory data, have been …
[O I] sub-arcsecond study of a microjet from an intermediate mass young star: RY Tauri
Dougados, C.; Cabrit, S.; Ferruit, P. +2 more
Context: High-resolution studies of microjets in T Tauri stars (cTTs) reveal key information on the jet collimation and launching mechanism, but only a handful of systems have been mapped so far.
Aims: We wish to perform a detailed study of the microjet from the 2 M⊙ young star RY Tau, to investigate the influence of its higher stel…
Observations and 3D MHD simulations of a solar active region jet
Gontikakis, C.; Tsinganos, K.; Archontis, V.
Aims: We study an active region jet originating from NOAA 8531 on May 15 1999. We perform 3D MHD numerical simulations of magnetic flux emergence and its subsequent reconnection with preexisting magnetic flux. Then, we compare the physical properties of the observed jet with the reconnecting outflow produced in the numerical model.
Methods: We…
Neutral interstellar hydrogen in the inner heliosphere under the influence of wavelength-dependent solar radiation pressure
Bzowski, M.; Tarnopolski, S.
Context: With the plethora of detailed results from heliospheric missions such as Ulysses and SOHO and at the advent of the first mission dedicated to in situ studies of neutral heliospheric atoms IBEX, we have entered the era of precision heliospheric studies. Interpretation of these data requires precision modeling, with second-order effects qua…
Modelling the spectral response of the Swift-XRT CCD camera: experience learnt from in-flight calibration
Campana, S.; Cusumano, G.; Moretti, A. +11 more
Context: Since its launch in November 2004, Swift has revolutionised our understanding of gamma-ray bursts. The X-ray telescope (XRT), one of the three instruments on board Swift, has played a key role in providing essential positions, timing, and spectroscopy of more than 300 GRB afterglows to date. Although Swift was designed to observe GRB afte…
Statistics of convective collapse events in the photosphere and chromosphere observed with the Hinode SOT
Lites, B. W.; de Wijn, A. G.; Fischer, C. E. +2 more
Convective collapse, a theoretically predicted process that intensifies existing weak magnetic fields in the solar atmosphere, was first directly observed in a single event by Nagata et al. (2008, ApJ, 677, L145) using the high resolution Solar Optical Telescope (SOT) of the Hinode satellite. Using the same space telescope, we observed 49 such eve…
A comprehensive study of large-scale structures in the GOODS-SOUTH field up to z ∼ 2.5
Fiore, F.; Castellano, M.; Pentericci, L. +14 more
Aims: The aim of the present paper is to identify and study the properties and galactic content of groups and clusters in the GOODS-South field up to z∼ 2.5, and to analyse the physical properties of galaxies as a continuous function of environmental density up to high redshift.
Methods: We used the deep (z850∼ 26), multi-wavelength…
The X17.2 flare occurred in NOAA 10486: an example of filament destabilization caused by a domino effect
Guglielmino, S. L.; Romano, P.; Contarino, L. +6 more
Context: It is now possible to distinguish between two main models describing the mechanisms responsible for eruptive flares : the standard model, which assumes that most of the energy is released, by magnetic reconnection, in the region hosting the core of a sheared magnetic field, and the breakout model, which assumes reconnection occurs at firs…
Properties of the nuclei and comae of 13 ecliptic comets from Hubble Space Telescope snapshot observations
Jorda, L.; Lamy, P. L.; A'Hearn, M. F. +2 more
Context: Knowledge of the size distribution of cometary nuclei and, more generally, of their physical properties is important for constraining models of the formation and evolution of the Solar System.
Aims: We report on our on-going effort to determine the ensemble properties of comets based on our success in detecting the nuclei of active c…
The enigmatic X-rays from the Herbig star HD 163296: Jet, accretion, or corona?
Schmitt, J. H. M. M.; Günther, H. M.
Context: Herbig Ae/Be stars (HAeBe) are pre-main sequence objects in the mass range 2 M⊙ < M* < 8 M⊙. Their X-ray properties are uncertain and, as yet, unexplained.
Aims: We want to elucidate the X-ray generating mechanism in HAeBes.
Methods: We present an XMM-Newton observation of the HAeBe HD 163296…