Search Publications
Variability of Titan's induced magnetotail: Cassini magnetometer observations
Dougherty, Michele K.; Simon, Sven; Neubauer, Fritz M. +1 more
We study the structure and variability of Titan's magnetotail by analyzing Cassini magnetic field observations from all tail crossings between 2005 and 2013. Titan's magnetotail is strongly affected by fluctuations in the ambient magnetospheric field conditions. Therefore, even Titan flybys with nearly identical trajectories may reveal a completel…
Forecast of solar proton flux profiles for well-connected events
Moon, Yong-Jae; Ji, Eun-Young; Park, Jinhye
We have developed a forecast model of solar proton flux profiles (> 10 MeV channel) for well-connected events. Among 136 solar proton events (SPEs) from 1986 to 2006, we select 49 well-connected ones that are all associated with single X-ray flares stronger than M1 class and start to increase within 4 h after their X-ray peak times. These event…
A refined classification of SPEs based on the multienergy channel observations
Cho, K. -S.; Kim, R. -S.; Park, Y. -D. +2 more
We have investigated characteristics of solar proton events (SPEs) and their association with other types of solar eruption using 42 SPEs observed with SOlar and Heliospheric Observatory/Energetic and Relativistic Nuclei and Electron detector from 1997 to 2012. A velocity dispersion analysis was performed to correctly estimate the onset times of p…
An unusual long-lived relativistic electron enhancement event excited by sequential CMEs
Yang, Xiao C.; Zhu, Guang W.; Zhang, Xiao X. +3 more
An unusual long-lived intense relativistic electron enhancement event from July to August 2004 is examined using data from Fengyun-1, POES, GOES, ACE, the Cluster Mission, and geomagnetic indices. During the initial 6 days of this event, the observed fluxes in the outer zone enhanced continuously, and their maximum increased from 2.1 × 102
Rotational/compressional nature of the magnetopause: Application of the BV technique on a magnetopause case study
Dorville, Nicolas; Belmont, Gérard; Rezeau, Laurence +2 more
The magnetopause boundary implies two main kinds of variations: a density/temperature gradient and a magnetic field rotation. Other variations are associated with these two, concerning in particular the flow velocity, the electric field, and the plasma composition. Compressional and rotational variations are always observed in a close vicinity of …
In situ observations of density cavities extending above the auroral acceleration region
Karlsson, T.; Marklund, G. T.; Alm, L.
The uppermost part of a stable potential structure in the auroral acceleration region was studied using simultaneous observations of Cluster satellites C1 and C3. Both satellites observe a monotonically decreasing electron density as they ascend through the auroral acceleration region. As C1 exits the top of the auroral acceleration region, the el…
Comparison of interplanetary CME arrival times and solar wind parameters based on the WSA-ENLIL model with three cone types and observations
Moon, Y. -J.; Jang, Soojeong; Na, Hyeonock +1 more
We have made a comparison between coronal mass ejection (CME)-associated shock propagations based on the Wang-Sheeley-Arge (WSA)-ENLIL model using three cone types and in situ observations. For this we use 28 full-halo CMEs, whose cone parameters are determined and their corresponding interplanetary shocks were observed at the Earth, from 2001 to …
Cluster observations of hot He+ events in the inner magnetosphere
Yamauchi, M.; Dandouras, I.; Nilsson, H. +1 more
In the inner magnetosphere inside 65° invariant latitude, Cluster Ion Spectrometry detected hot He+ events of about a few tens to several hundred eV without the same types of hot H+ signature at the same energy. During the 2001-2006 period when the Cluster orbit was almost constant and approximately north-south symmetric at c…
Signals of solar cosmic ray flux variations inferred from the noise in raw CCD solar images taken by SOHO/EIT
Chae, Jongchul; Oh, Suyeon; Yi, Yu +1 more
The noise embedded in the raw data in one scientific discipline has sometimes been proven to be a valuable signal for another discipline, and there are examples throughout science history. The solar images taken by the solid state detectors (CCDs) of the Sun monitoring satellites are usually cleaned by removing the traces of cosmic rays on the raw…
Technique for measuring and correcting the Taylor microscale
Dasso, S.; Matthaeus, W. H.; Smith, C. W. +3 more
We discuss and develop methods to estimate and refine measurements of the Taylor microscale from discrete data sets. To study how well a method works, we construct a time series of discrete data with a known power spectrum and Taylor scale, but with various truncations of the resolution that eliminate higher frequencies in a controlled fashion. We…