Search Publications
Cross-Calibration of TIMED SEE and SOHO EIT Irradiances
Eparvier, F. G.; Hock, R. A.
Absolutely calibrated solar images are necessary for a variety of solar physics problems, such as the identification of solar variability sources and the derivation of differential emission measure (DEM) maps. SOHO EIT is absolutely calibrated by using TIMED SEE spectra to provide a method of determining physical values of irradiance for EIT image…
Energetic electron asymmetries at Mars: ASPERA-3 observations
Barabash, S.; Lundin, R.; Winningham, J. D. +7 more
Energetic electron fluxes from more than two years of ASPERA-3 observations are organized in different coordinate systems for the investigation of asymmetries in the global dynamics of the Martian magnetosphere. A clear asymmetry is found in the distribution of high-flux events with respect to the solar wind convective electric field ( Esw
On the performance of a dual-beam polarimeter at Kodaikanal Tower Telescope
Singh, Jagdev; Sankarasubramanian, K.; Ramesh, K. B. +4 more
Calibration and characterization of a dual-beam polarimeter installed at Kodaikanal Tower Telescope (KTT) for spectropolarimetric observations are presented in this paper. It was found that a slit width of 48 µ is optimum for the spectrograph setup at KTT and corresponding spectral resolution is 32.47 mÅ. It was demonstrated that the precisi…
Observational study of magnetic chirality of solar active regions
Zhang, H. Q.
We present the evolution of magnetic field and relationship with the magnetic (current) helicity in solar active regions from a series of photospheric vector magnetograms obtained at Huairou Solar Observing Station near Beijing, and also longitudinal magnetograms by MDI of SOHO, white light and 171 Å images by TRACE and soft X-ray images by Yohkoh…
Solar-like oscillations in red giants in the CoRoT exofield
De Ridder, J.; Barban, C.; Hekker, S. +4 more
Asteroseismic observations from space can provide us with long time series of uninterrupted high quality data for many stars at the same time. The CoRoT satellite (Convection Rota- tion and planetary Transits) was launched successfully in December 2006 and provides high precision photometery for a large number of stars. Here we present our researc…
A general Cluster data and global MHD simulation comparison
Daum, P.; Wild, J. A.; Taylor, M. G. G. T. +3 more
Among the many challenges facing the space weather modelling community today, is the need for validation and verification methods of the numerical models available describing the complex nonlinear Sun-Earth system. Magnetohydrodynamic (MHD) models represent the latest numerical models of this environment and have the unique ability to span the eno…
XMM-Newton: The next decade
Schartel, N.
Some key numbers about the XMM-Newton users, usage of the mission and the scientific outcome are provided. The background for selecting the topic, the preparation work, the organization and the corresponding committees are briefly described.
Emission from Large-Scale Jets in Quasars
Uchiyama, Yasunobu
We consider the emission processes in the large-scale jets of powerful quasars based on the results obtained with the VLA, Spitzer, Hubble, and Chandra. We show that two archetypal jets, 3C 273 and PKS 1136-135, have two distinct spectral components on large-scales: (1) the low-energy (LE) synchrotron spectrum extending from radio to infrared, and…
Grad-Shafranov and MHD Reconstructions
Hasegawa, Hiroshi; Sonnerup, Bengt U. O.; Teh, Wai-Leong
Since the publication of the multi-spacecraft data analysis book ISSI SR-001, new methods have been developed that allow field and plasma structures traversed by one or more spacecraft to be reconstructed in a region surrounding the spacecraft path from the measured data. Maps of field and plasma properties are created with the aid of various vers…
Calibration techniques for magnetometers implementing on-board de-spinning algorithms
Balogh, A.; Lucek, E.; Dunlop, M. W. +4 more
The Fluxgate Magnetometer experiments on-board the European Space Agency’s four spacecraft Cluster Mission have the capability to store sampled magnetic field vectors in the instrument memory, either as a full resolution ‘event capture’ or as spin-resolution vectors transformed into a non-spinning co-ordinate system (de-spun). The latter capabilit…