Search Publications
The X-ray emission of the γ Cassiopeiae stars
Smith, Myron A.; Motch, C.; Lopes de Oliveira, R.
Long considered as the ;odd man out; among X-ray emitting Be stars, γ Cas (B0.5e IV) is now recognized as the prototype of a class of stars that emit hard thermal X-rays. Our classification differs from the historical use of the term ; γ Cas stars; defined from optical properties alone. The luminosity output of this class contributes significantly…
Interaction between reconnection and Kelvin-Helmholtz at the high-latitude magnetopause
Zhang, Hui; Ma, Xuanye; Otto, Antonius +1 more
On March 23, 2002, Cluster satellites recorded an event, which has been interpreted as reconnection, during an outward crossing near the dawn side cusp region in the Northern Hemisphere. The event showed a large perturbation in the magnetic normal component, inconsistent with a one-dimensional reconnection layer configuration, and causing a poor r…
The Kelvin-Helmholtz instability under Parker-Spiral Interplanetary Magnetic Field conditions at the magnetospheric flanks
Adamson, E.; Otto, A.; Nykyri, K.
We have generated fully three-dimensional, high-resolution magnetohydrodynamic (MHD) simulations of the Kelvin-Helmholtz (KH) Instability during Parker-Spiral Interplanetary Magnetic Field (IMF) conditions at the dawnside magnetospheric flank magnetopause. Results of these simulations show that, although the draping of a strong tangential magnetic…
Contribution from SOIR/VEX to the updated Venus International Reference Atmosphere (VIRA)
Vandaele, A. C.; Trompet, L.; Robert, S. +9 more
The SOIR instrument on-board Venus Express is an infrared spectrometer covering the 2.2-4.3 µm spectral region. This instrument allows the detection of several key species of the Venus atmosphere, including CO2, CO, H2O/HDO, HCl, HF and SO2. From the CO2 density measurements, temperature is inferre…
Chandrayaan-2 dual-frequency SAR: Further investigation into lunar water and regolith
Das, Anup; Putrevu, Deepak; Vachhani, J. G. +2 more
The Space Applications Centre (SAC), one of the major centers of the Indian Space Research Organization (ISRO), is developing a high resolution, dual-frequency Synthetic Aperture Radar as a science payload on Chandrayaan-2, ISRO's second moon mission. With this instrument, ISRO aims to further the ongoing studies of the data from S-band MiniSAR on…
Distribution of hydrogen and oxygen ion species in the plasmasheet
Wang, Jing; Cao, Jinbin; Liu, Wenlong
In this paper, using data obtained by Cluster 4 satellite from 2001 to 2012, we statistically investigate the spatial distributions of H+ and O+ in the magnetotail plasmasheet and their relation with geomagnetic indices. Our work outlines the existence of two regions with enhanced O+ concentration in the tail plasm…
Minute pulsations in microwaves and X-rays during the flare on May 6, 2005
Kupriyanova, E. G.; Ratcliffe, H.
Quasi-periodic pulsations are a common feature in the emission associated with solar flares. In particular, pulsations with periods of tens of seconds to a few minutes are often seen in microwave and hard X-ray emission. We examine the spatial and temporal structure of the emission during the flare on May 6, 2005. The source of the flare is a magn…
The ESPAS e-infrastructure: Access to data from near-Earth space
Hapgood, Mike; Belehaki, Anna; James, Sarah +9 more
ESPAS, the ;near-Earth space data infrastructure for e-science; is a data e-infrastructure facilitating discovery and access to observations, ground-based and space borne, and to model predictions of the near-Earth space environment, a region extending from the Earth's atmosphere up to the outer radiation belts. ESPAS provides access to metadata a…
Phase relations between total solar irradiance and the Mg II index
Li, K. J.; Xu, J. C.; Feng, W. +1 more
The Mg II index is usually used to represent the brightening contribution to total solar irradiance (TSI) by solar bright structures, such as faculae and network. In order to understand variations of TSI, phase relations of TSI and the chromospheric Mg II index is investigated on time-scales of one year and longer. The NOAA daily Mg II index at th…
X-rays from magnetic intermediate mass Ap/Bp stars
Robrade, Jan
The X-ray emission of magnetic intermediate mass Ap/Bp stars is reviewed and put into context of intrinsic as well as extrinsic hypotheses for its origin. New X-ray observations of Ap/Bp stars are presented and combined with an updated analysis of the available datasets, providing the largest sample of its type that is currently available. In the …