Search Publications
Missions
Journals
Publication Years
Cluster observations of particle acceleration up to supra-thermal energies in the cusp region related to low-frequency wave activity - possible implications for the substorm initiation process
Dandouras, I.; Zhang, H.; Zong, Q. -G. +6 more
The purpose of our study is to investigate the way particles are accelerated up to supra-thermal energies in the cusp diamagnetic cavities. For this reason we have examined a number of Cluster cusp crossings, originally identified by Zhang et al. (2005), for the years 2001 and 2002 using data from RAPID, STAFF, EFW, CIS, PEACE, and FGM experiments…
The Absolute Flux Distribution of LDS749B
Koester, D.; Bohlin, R. C.
Observations from the Space Telescope Imaging Spectrograph (STIS) define the flux of the DBQ4 star LDS749B from 0.12 to 1.0 µm with an uncertainty of ~1% relative to the three pure hydrogen white dwarf primary Hubble Space Telescope standards. With T eff = 13,575 K, log g = 8.05, and a trace of carbon at 1 × 10-6 of sol…
On the Formation of Perseus OB1 at High Galactic Latitudes
Lim, Jeremy; Lee, Hsu-Tai
The Per OB1 association, which contains the remarkable double cluster h and χ Per, is unusual in not having a giant molecular cloud in its vicinity. We show from Hipparcos data that the luminous members of this association exhibit a bulk motion away from the Galactic plane, such that their average velocity increases with height above the Galactic …
HST spectral imaging of Titan's haze and methane profile between 0.6 and 1 µm during the 2000 opposition
Young, E. F.; Anderson, C. M.; McKay, C. P. +1 more
We report on the analysis of high spatial resolution visible to near-infrared spectral images of Titan at L=240° in November 2000, obtained with the Space Telescope Imaging Spectrograph instrument on board the Hubble Space Telescope as part of program GO-8580. We employ a radiative transfer fractal particle aerosol model with a Bayesian parameter …
SUMER observations of the inverse Evershed effect in the transition region above a sunspot
Solanki, S. K.; Curdt, W.; Teriaca, L.
Aims: We analyse SUMER spectral scans of a large sunspot within active region NOAA 10923, obtained on 14-15 November 2006, to determine the morphology and dynamics of the sunspot atmosphere at different heights/temperatures.
Methods: The data analysed here consist of spectroheliograms in the continuum around 142.0 nm and in the Si iv 140.2 nm,…
Different triggering mechanisms for solar flares and coronal mass ejections
Lippiello, E.; de Arcangelis, L.; Godano, C.
Context: Experimental observations indicate that flares and CMEs are often associated, even if the precise relationship between the two phenomena is a still hot and open question.
Aims: We present a study of the statistical properties of solar flare and CME temporal organisation, in order to enlighten differences in the mechanisms at the basis…
Obscured Sources and Supergiant Fast X-ray Transients: New Classes of High Mass X-ray Binaries
Chaty, S.
A new type of high-energy binary systems has been revealed by the INTEGRAL satellite. These sources are in the course of being unveiled by means of multi-wavelength optical, near-and mid-infrared observations. Among these sources, two distinct classes are appearing: the first one is constituted of intrinsically obscured high-energy sources, of whi…
ATCA observations of the very young Planetary Nebula SAO 244567
Umana, G.; Trigilio, C.; Leto, P. +2 more
The radio emission from the youngest known Planetary Nebula, SAO244567, has been mapped at 1384, 2368, 4800, 8640, 16832 and 18752 MHz by using the Australian Telescope Compact Array (ATCA). These observations constitute the first detailed radio study of this very interesting object, as they allow us to obtain the overall radio morphology of the s…
A feasibility study for measuring geomagnetic conversion of solar axions to x-rays in low Earth orbits
Davoudiasl, Hooman; Huber, Patrick
We present a detailed computation of the expected rate for geomagnetic conversion of solar axions to x-rays (GECOSAX) along the orbit of an x-ray satellite. We use realistic satellite orbits and propagation in time. A realistic model for the Earth's magnetic field, which properly accounts for its spatial non-uniformity, is used. We also account fo…
Collisional interaction limits between dark matter particles and baryons in `cooling flow' clusters
Hu, Jian; Lou, Yu-Qing
Presuming weak collisional interactions to exchange the kinetic energy between dark matter and baryonic matter in a galaxy cluster, we re-examine the effectiveness of this process in several `cooling flow' galaxy clusters using available X-ray observations and infer an upper limit on the heavy dark matter particle (DMP)-proton cross-section σ…