Search Publications
Nonlinear dynamics of foreshock structures: Application of nonlinear autoregressive moving average with exogenous inputs model to Cluster data
Dunlop, M. W.; Balikhin, M. A.; Gedalin, M. +6 more
Nonlinear processes identification techniques based on multi-input nonlinear autoregressive moving average with exogenous inputs model has been applied to four-point Cluster measurements in order to study nonlinear processes that take place in the terrestrial foreshock. It is shown that both quadratic and cubic processes are involved in the evolut…
Substorm onset dynamics in the magnetotail as derived from joint TC-1 and Cluster data analysis
Wang, H.; Lühr, H.; Ridley, A. J. +1 more
This study investigates two substorm onset events with favorable constellations of spacecraft, TC-1 and Cluster, separated by several Earth radii. The substorms have been identified in both auroral regions. One is believed to be triggered by a northward turning of the interplanetary magnetic field (IMF), while the other occurs under generally sout…
XMMU J134736.6+173403: an eclipsing LMXB in quiescence or a peculiar AGN?
Altieri, B.; King, A. R.; Nucita, A. +2 more
Aims:We report the discovery of a peculiar object observed serendipitously with XMM-Newton. We present its timing and spectral properties and investigate its optical counterpart.
Methods: The light curve of the X-ray source, its spectrum, and the spectrum of the best optical counterpart are presented and analyzed.
Results: The X-ray flux d…
A solar eruption triggered by merge interactions of different helicity loops
Shen, F.; Song, W.; Feng, X.
Aims: We investigate the magnetic evolution of a flare/CME source region to determine the trigger of the flare and the EUV brightening event. Also, we discuss the role of the current helicity (h_c) in solar activity.
Methods: We use the long duration sequences of SOHO/MDI magnetograms and TRACE 195 Å images for a super active region (AR), NOAA…
VERA Observations of SiO Masers in the Symbiotic Star R Aquarii
Hirota, Tomoya; Kurayama, Tomoharu; Honma, Mareki +28 more
We present phase-referenced maps of the SiO maser transitions v = 1 J = 1--0 and v = 2 J = 1--0 from the symbiotic stellar system R Aquarii, which hosts an evolved AGB star plus a hot companion. Observations were performed at two epochs: 2004.98 and 2005.98. Accurate absolute coordinates and proper motions of the emission centroid were obtained; t…
Introduction to the special section on Venus Express: Results of the Nominal Mission
Taylor, F. W.; Titov, D. V.; Svedhem, H.
Abstract Available from http://www.agu.org
Analysis of Two Coronal Loops with Combined TRACE and SOHO/CDS Data
Martens, P. C. H.; Cirtain, J. W.; Scott, J. T.
We use an innovative research technique to analyze combined images from the Coronal Diagnostic Spectrometer (CDS) on the Solar and Heliospheric Observatory (SOHO) and the Transition Region and Coronal Explorer (TRACE). We produce a high spatial and temporal resolution simulated CDS raster or "composite" map from TRACE data and use this composite m…
Coronal Mass Ejections, Magnetic Fields, and the Green Corona in Cycle 23
Rušin, V.; Minarovjech, M.; Saniga, M.
We study a time - latitudinal distribution of CMEs observed by the SOHO spacecraft, their projected speeds and associated magnetic fields, as well as the north - south (N - S) asymmetry of solar surface magnetic fields, and the coronal green line intensities. We have found that (a) there exists an intricate relation between the average projected v…
Near-Earth bursty bulk flows and AE index
Dunlop, M. W.; Baumjohann, W.; Carr, C. +5 more
With the 4-s resolution data of the magnetometer and the ion plasma analyzer on TC-1 from June to November of each year during the period of 2004-2006, we statistically analyzed the occurrence rate of both convective and field-aligned bursty flows (FABFs). A near-Earth bursty bulk flow (NEBBF) occurred during both the quiet time and substorm proce…
How Do f-Mode Frequencies Change with Solar Radius?
Antia, H. M.; Chatterjee, Piyali
We test the relation between relative f-mode frequency variation (δ ν/ν) and Lagrangian perturbation in the solar radius (δ r/r) obtained by Dziembowski and Goode using several pairs of solar models and show that it does not hold true for any of the model pairs we have used. We attempt to derive a better approximation for the kernel linking the re…