Search Publications
An XMM-Newton spatially-resolved study of metal abundance evolution in distant galaxy clusters
Molendi, S.; Gastaldello, F.; Tozzi, P. +3 more
Context. We present an XMM-Newton analysis of the X-ray spectra of 39 clusters of galaxies at 0.4 < z < 1.4, covering a temperature range of 1.5 ≲ kT ≲ 11 keV.
Aims: The main goal of this paper is to study how the abundance evolves with redshift not only by means of a single emission measurement performed on the whole cluster but also b…
Discovery of the millisecond pulsar PSR J2043+1711 in a Fermi source with the Nançay Radio Telescope
Camilo, F.; Guillemot, L.; Harding, A. K. +18 more
We report the discovery of the millisecond pulsar PSR J2043+1711 in a search of a Fermi Large Area Telescope (LAT) source with no known associations, with the Nançay Radio Telescope. The new pulsar, confirmed with the Green Bank Telescope, has a spin period of 2.38 ms, is relatively nearby (? kpc) and is in a 1.48-d orbit around a low-mass compani…
Stars, dust, and the growth of ultraviolet-selected sub-L* galaxies at redshift z∼ 2
Sawicki, Marcin
This work concerns the physical properties of very faint (?= 28 AB mag; Mstars,lim∼ 108 M⊙), ultraviolet-selected (UV-selected) sub-L* BX galaxies at z∼ 2.3. Stellar masses, dust content and dust-corrected star formation rates are constrained using broad-band spectral energy distribution fitting, resulting in a num…
Testing cosmology with extreme galaxy clusters
Harrison, Ian; Coles, Peter
Motivated by recent suggestions that a number of observed galaxy clusters have masses which are too high for their given redshift to occur naturally in a standard model cosmology, we use extreme value statistics to construct confidence regions in the mass-redshift plane for the most extreme objects expected in the universe. We show how such a diag…
Cassini observations of ion and electron beams at Saturn and their relationship to infrared auroral arcs
Coates, A. J.; Brown, R. H.; Baines, K. H. +14 more
We present Cassini Visual and Infrared Mapping Spectrometer observations of infrared auroral emissions from the noon sector of Saturn's ionosphere revealing multiple intense auroral arcs separated by dark regions poleward of the main oval. The arcs are interpreted as the ionospheric signatures of bursts of reconnection occurring at the dayside mag…
Analysis of Quiet-Sun Internetwork Magnetic Fields Based on Linear Polarization Signals
Bellot Rubio, L. R.; Orozco Suárez, D.
We present results from the analysis of Fe I 630 nm measurements of the quiet Sun taken with the spectropolarimeter of the Hinode satellite. Two data sets with noise levels of 1.2 × 10-3 and 3 × 10-4 are employed. We determine the distribution of field strengths and inclinations by inverting the two observations with a Milne-…
Basal magnetic flux and the local solar dynamo
Stenflo, J. O.
The average unsigned magnetic flux density in magnetograms of the quiet Sun is generally dominated by instrumental noise. Due to the entirely different scaling behavior of the noise and the solar magnetic pattern it has been possible to determine the standard deviation of the Gaussian noise distribution and remove the noise contribution from the a…
Detection of negative ions in the deep ionosphere of Titan during the Cassini T70 flyby
Wahlund, J. -E.; Edberg, N. J. T.; Ågren, K.
We present radio and plasma wave science (RPWS) Langmuir probe (LP) observations that give evidence for a population of heavy, negative ions at altitudes below 900 km in Titan's ionosphere during the Cassini T70 flyby. The negative ion density in this region is comparable to, or higher than, the electron density of 760 cm-3. Both positi…
Improved distance determination to M 51 from supernovae 2011dh and 2005cs
Garnavich, P. M.; Wheeler, J. C.; Pál, A. +9 more
Aims: The appearance of two recent supernovae, SN 2011dh and 2005cs, both in M 51, provides an opportunity to derive an improved distance to their host galaxy by combining the observations of both SNe.
Methods: We apply the Expanding Photosphere Method to get the distance to M 51 by fitting the data of these two SNe simultaneously. In or…
Shape modeling technique KOALA validated by ESA Rosetta at (21) Lutetia
Jorda, L.; Lara, L. M.; Bertaux, J. -L. +44 more
We present here a comparison of our results from ground-based observations of asteroid (21) Lutetia with imaging data acquired during the flyby of the asteroid by the ESA Rosetta mission. This flyby provided a unique opportunity to evaluate and calibrate our method of determination of size, 3-D shape, and spin of an asteroid from ground-based obse…