Search Publications
NSCC—A New Scheme of Classification of C-Rich Stars Devised from Optical and Infrared Observations
de Araújo, F. X.; Lorenz-Martins, S.; De Mello, A. B. +2 more
A new classification system for carbon-rich stars is presented based on an analysis of 51 asymptotic giant branch carbon stars through the most relevant classifying indices available. The extension incorporated, which also represents the major advantage of this new system, is the combination of the usual optical indices that describe the photosphe…
Helioseismic Travel-Time Definitions and Sensitivity to Horizontal Flows Obtained from Simulations of Solar Convection
Birch, Aaron C.; Couvidat, Sébastien
We study the sensitivity of wave travel times to steady and spatially homogeneous horizontal flows added to a realistic simulation of the solar convection performed by Robert F. Stein, Ake Nordlund, Dali Georgobiani, and David Benson. Three commonly used definitions of travel times are compared. We show that the relationship between travel-time di…
Impacts of Source Properties on Strong Lensing by Rich Galaxy Clusters
Mao, S.; Kong, X.; Jing, Y. P. +2 more
We use a high-resolution N-body simulation to investigate the influence of background galaxy properties, including redshift, size, shape, and clustering, on the efficiency of forming giant arcs by gravitational lensing of rich galaxy clusters. Two large sets of ray-tracing simulations are carried out for 10 massive clusters at two redshifts, i.e.,…
Dynamical evolution of Saturn's F ring dust particles
Sfair, R.; Winter, O. C.; Mourão, D. C. +1 more
Saturn's F ring has been the subject of study due to its peculiar structure and the proximity to two satellites, named Prometheus (interior) and Pandora (exterior to the ring), which cause perturbations to the ring particles. Early results from Voyager data have proposed that the ring is populated with centimetre- and micrometre-sized particles. T…
A method for the treatment of supergranulation advection by giant cells
Cuntz, M.; Williams, P. E.
Aims: We present a new method for the treatment of the advection of solar supergranulation by giant cells, a large-scale analogue to the observed property of granule advection by supergranules.
Methods: The proposed method is derived from a description of solar convection via spherical harmonics and spectral coefficients, allowing the investig…
Interpretation of the SOHO/UVCS observations of two CME-driven shocks
Mancuso, Salvatore; Bemporad, Alessandro
We report on the analysis of two fast CME-driven shocks observed with the UltraViolet Coronagraph Spectrometer (UVCS) on board the Solar and Heliospheric Observatory (SOHO). The first event, detected on 2002 March 22 at 4.1 R⊙ with the UVCS slit placed in correspondence with the flank of the expanding CME surface, represents the highest…
Photometric Survey of Stellar Clusters in the Outer Part of M33. II. Analysis of HST/ACS Images
Kaluzny, J.; Zloczewski, K.
We have used deep ACS/WFC images of M33 to check the nature of extended objects detected by the ground based survey of Zloczewski etal (2008). A total of 24 candidates turned out to be genuine compact stellar clusters. In addition we detected 91 new clusters. Equatorial coordinates, integrated magnitudes and angular sizes are listed for all 115 ob…
The radial dependence of temperature and iron abundance. Galaxy clusters from z = 0.14 to z = 0.89
Ehlert, S.; Ulmer, M. P.
Context: The origin and evolution of the intracluster medium (ICM) are still not fully understood. A better understanding is not only interesting in its own right, but it is also important for modeling hierarchical structure growth and for using cluster surveys to determine cosmological parameters.
Aims: To determine if there exists any eviden…
Statistical analysis of the observations of the MEX/ASPERA-3 NPI in the shadow
Kallio, E.; Barabash, S.; Lundin, R. +17 more
The analyser of space plasma and energetic atoms (ASPERA-3) neutral particle imager (NPI) on board Mars Express (MEX) is devoted to energetic neutral atom (ENA) detection within the Martian environment. These ENAs originate from the interaction between the energetic ions flowing inside the Martian environment and the exospheric neutral gas, thus p…
Observation of Universality in the Generalized Similarity of Evolving Solar Wind Turbulence as Seen by Ulysses
Carbone, V.; Chapman, S. C.; Leonardis, E. +2 more
We perform statistical analysis of the fluctuating magnetic field observed in-situ by the Ulysses spacecraft, from the perspective of quantitative characterization of the evolving magnetohydrodynamic (MHD) turbulence. We focus on two successive polar passes around solar minimum which provide extended intervals of quiet, fast solar wind at a range …