Search Publications
Subwavelength Resolution Imaging of the Solar Deep Interior
Duvall, Thomas L., Jr.; Hanasoge, Shravan M.
We derive expectations for signatures in the measured travel times of waves that interact with thermal anomalies and jets. A series of numerical experiments that involve the dynamic linear evolution of an acoustic wave field in a solarlike stratified spherical shell in the presence of fully three-dimensional time-stationary perturbations are perfo…
The formation and evolution of massive stellar clusters in IC4662
Vacca, William D.; Gilbert, Andrea M.
We present a multiwavelength study of the formation of massive stellar clusters, their emergence from cocoons of gas and dust, and their feedback on surrounding matter. Using data that span from radio to optical wavelengths, including Spitzer and Hubble Space Telescope ACS observations, we examine the population of young star clusters in the centr…
Infrared spectral variations of three Mira variable carbon stars with the 11.3 µm SiC feature
Chen, Pei-Sheng; Shan, Hong-Guang; Yang, Xiao-Hong +1 more
The spectral variations of three Mira variable carbon stars, V CrB, T Dra and V Cyg in the infrared are investigated based on ISO SWS data. It is found that either continua or molecular/dust features were variable with time in the infrared for these carbon stars during one and a half year observations. When stars were brighter the infrared continu…
Estimating the magnetic energy inside traveling compression regions
Nakamura, R.; Baumjohann, W.; Semenov, V. S. +3 more
We investigate a series of six TCRs (traveling compression regions), appearing in the course of a small substorm on 19 September 2001. Except for two of these TCRs, all Cluster spacecraft were located in the lobe and detected the typical signatures of TCRs, i.e., compressions in |B| and bipolar Bz variations. We use these perturbations …
Latitudinal dependence of the solar wind density derived from remote sensing measurements using interplanetary Lyman α emission from 1999 to 2002
Lallement, Rosine; Taguchi, Makoto; Fukunishi, Hiroshi +3 more
The interplanetary Lyman α backscattered emission is an effective tool for remote sensing of the global structure of the solar wind proton flux. This paper reports an attempt to derive the latitudinal dependence of the solar wind density by combining the interplanetary Lyman α measurements of the Nozomi spacecraft for the period 1999–2002 with the…
X-Ray Emission of Cataclysmic Variables Observed by Integral
Paltani, S.; Gális, R.; Eckert, D. +2 more
Magnetic cataclysmic variables represent a significant fraction of all INTEGRAL detections in hard X-rays and soft gamma rays. Our deep survey of all known intermediate polars revealed five new sources, previously undetected by this mission. Our analysis, based on all available observational data from the IBIS and JEM-X instruments, has shown that…
Velocity fluctuations in polar solar wind: a comparison between different solar cycles
Bavassano, B.; Bruno, R.; D'Amicis, R.
The polar solar wind is a fast, tenuous and steady flow that, with the exception of a relatively short phase around the Sun's activity maximum, fills the high-latitude heliosphere. The polar wind properties have been extensively investigated by Ulysses, the first spacecraft able to perform in-situ measurements in the high-latitude heliosphere. The…
Solar wind elemental abundances related to the Sun's open magnetic flux
Wurz, P.; Klecker, B.; Wang, X.
Context: We present an investigation of the effects of solar magnetic field on the elemental abundance ratios of heavy ions in the solar wind.
Aims: We compare the elemental abundance ratios Fe/O, Si/O, Mg/O, Ne/O, and C/O over the 23rd solar cycle, attention being given to the varying fraction of open magnetic flux on the visible side of the …
Correlation between the parameters of coronal mass ejections and features of their propagation in the corona with the large-scale structure of the solar magnetic field
Ivanov, E. V.; Fainshtein, V. G.; Rudenko, G. V.
Correlation between the parameters of coronal mass ejections (CMEs) that are detected on the LASCO coronographs and are associated with eruptive prominences and the distances of CME axes from the coronal streamer belt has been analyzed. The deviations of CME trajectories from the radial direction have been investigated.
Star formation history in the central region of the barred galaxy NGC 4245
Afanasiev, V. L.; Chilingarian, I. V.; Sil'Chenko, O. K.
We have investigated the gas and stellar kinematics and the stellar population properties at the center of the early-type galaxy NGC 4245 with a large-scale bar by the method of two-dimensional spectroscopy. The galaxy has been found to possess a pronounced chemically decoupled compact stellar nucleus, which is at least a factor of 2.5 richer in m…