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G. Le Chat A. Zaslavsky N. Meyer-Vernet K. Issautier S. Belheouane F. Pantellini M. Maksimovic I. Zouganelis S. D. Bale J. C. Kasper 《Solar physics》2013,286(2):549-559
New measurements using radio and plasma-wave instruments in interplanetary space have shown that nanometer-scale dust, or nanodust, is a significant contributor to the total mass in interplanetary space. Better measurements of nanodust will allow us to determine where it comes from and the extent to which it interacts with the solar wind. When one of these nanodust grains impacts a spacecraft, it creates an expanding plasma cloud, which perturbs the photoelectron currents. This leads to a voltage pulse between the spacecraft body and the antenna. Nanodust has a high charge/mass ratio, and therefore can be accelerated by the interplanetary magnetic field to the speed of the solar wind: significantly faster than the Keplerian orbital speeds of heavier dust. The amplitude of the signal induced by a dust grain grows much more strongly with speed than with mass of the dust particle. As a result, nanodust can produce a strong signal despite its low mass. The WAVES instruments on the twin Solar TErrestrial RElations Observatory spacecraft have observed interplanetary nanodust particles since shortly after their launch in 2006. After describing a new and improved analysis of the last five years of STEREO/WAVES Low Frequency Receiver data, we present a statistical survey of the nanodust characteristics, namely the rise time of the pulse voltage and the flux of nanodust. We show that previous measurements and interplanetary dust models agree with this survey. The temporal variations of the nanodust flux are also discussed. 相似文献
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Nicolas Saspiturry Ccile Allanic Philippe Razin Benoit Issautier Thierry Baudin Eric Lasseur Olivier Serrano Sophie Leleu 《地学学报》2020,32(4):253-260
The Early Cretaceous hyperextended Mauléon rift is localized in the north‐western Pyrenean orogen. We infer the Tertiary evolution of the Mauléon basin through the restoration of a 153‐km‐long crustal‐scale balanced cross‐section of the Pyrenean belt, which documents at least 67 km (31%) of orogenic shortening in the Western Pyrenees. Initial shortening, accommodated through inversion of inherited crustal structures, led to formation of a pop‐up structure, in which the opposite edges underwent similar shortening with different tectonic reactivation styles, localized versus. distributed. Underthrusting of the Iberian margin accommodated further convergence, forming the Axial Zone antiformal stack of crustal nappes within a lithospheric pop‐up. Thin‐skinned and thick‐skinned structures propagated outward from the heart of this pop‐up, a block of strong mantle acting as a buttress inhibiting complete inversion of the Mauléon rift basin. 相似文献
3.
Yury V. Chugunov Anna Yu. Kazarova Eugene A. Mareev Michel Moncuquet Karine Issautier Nicole Meyer-Vernet 《Astrophysics and Space Science》2001,277(1-2):313-316
Quasi-thermal noise (QTN) spectroscopy is one of the most effective tools for in situ diagnostics in space plasmas (Meyer-Vernet et al., 1998; Meyer-Vernet and Perche, 1989; Chugunov and Trakhtengerts, 1978). This method produces routine measurements of the
bulk electron density and temperature; recently it has been extended to measure the ion bulk speed. Among the advantages of
the method its immunity to spacecraft potential and photoelectron perturbations should be noted. Quasi-thermal noise spectroscopy
is used particularly on Ulysses and Wind. However for the interpretation of QTN data the calculation of the noise voltage
induced on antennas under different conditions is necessary. This question is especially complicated and so far insufficiently
studied in magnetized plasmas. In the present paper we calculate the spectrum of the noise voltage induced on a dipole antenna
in the upper hybrid frequency range. The computations are adapted to the interpretation of data acquired on the Ulysses and
Wind spacecraft.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
We present the solar wind plasma parameters obtained from the Ulysses spacecraft during its second pole-to-pole fast latitude scan near the 2001 solar maximum. We study the solar wind properties
from the electron density and core temperature measurements made by the radio receiver on Ulysses using the method of quasi-thermal noise spectroscopy. We analyze these parameters as functions of heliographic latitude and
distance. We present their histograms normalized to 1 AU and find a bimodal distribution for the electron core temperature.
The cooler population can be associated with the fast wind flow emanating from coronal holes present at various latitudes.
We discuss a slight north/south asymmetry found for the electron density. Finally, we compare the present results to those
obtained during the 1996 solar minimum and 1991 solar maximum. 相似文献
5.
The transport of energy in space plasmas, especially in the solar wind, is far from being understood. Measuring the temperature of the electrons and their non-thermal properties is essential to understand the transport properties in collisionless plasmas. Quasi-thermal noise spectroscopy is a reliable tool for measuring the electron temperature accurately since it is less sensitive to the spacecraft perturbations than particle detectors. We apply this method to Ulysses radio data obtained during the first pole-to-pole fast latitude scan in the high-speed solar wind, using a kappa function to describe the electron velocity distribution. We deduce the variations with heliocentric distance between 1.5 and 2.3 AU in the fast solar wind at high latitude in terms of three fitting parameters: the electron density varies as n e??R ?1.96±0.08, the electron temperature as T e??R ?0.53±0.15, and the kappa index of the distribution remains constant at ??=2.0±0.2. These observations agree with the predictions of the exospheric theory. 相似文献
6.
The Solar Wind Energy Flux 总被引：1，自引：0，他引：1
The solar-wind energy flux measured near the Ecliptic is known to be independent of the solar-wind speed. Using plasma data from Helios, Ulysses, and Wind covering a large range of latitudes and time, we show that the solar-wind energy flux is independent of the solar-wind speed and latitude within 10?%, and that this quantity varies weakly over the solar cycle. In other words the energy flux appears as a global solar constant. We also show that the very high-speed solar wind (V SW>700?km?s?1) has the same mean energy flux as the slower wind (V SW<700?km?s?1), but with a different histogram. We use this result to deduce a relation between the solar-wind speed and density, which formalizes the anti-correlation between these quantities. 相似文献
7.
Belheouane S. Zaslavsky A. Meyer-Vernet N. Issautier K. Mann I. Maksimovic M. 《Solar physics》2012,281(1):501-506
Most in situ measurements of cosmic dust have been carried out with dedicated dust instruments. However, dust particles can also be detected with radio and plasma wave instruments. The high velocity impact of a dust particle generates a small crater on the spacecraft, and the dust particle and the crater material are vaporised and partly ionised. The resulting electric charge can be detected with plasma instruments designed to measure electric waves. Since 2007 the STEREO/WAVES instrument has recorded a large number of events due to dust impacts. Here we will concentrate on the study of those impacts produced by dust grains originating from the local interstellar cloud. We present these fluxes during five years of the STEREO mission. Based on model calculations, we determine the direction of arrival of interstellar dust. We find that the interstellar dust direction of arrival is ～260°, in agreement with previous studies.
相似文献8.
Karine Issautier Nicole Meyer-Vernet Viviane Pierrard Joseph Lemaire 《Astrophysics and Space Science》2001,277(1-2):189-193
We use a kinetic collisionless model of the solar wind to calculate the radial variation of the electron temperature and obtain
analytical expressions at large radial distances. In order to be compared with Ulysses observations, the model, which initially
assumed a radial magnetic field, has been generalized to a spiral magnetic field. We present a preliminary comparison with
Ulysses observations in the fast solar wind at high heliospheric latitudes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
K. Issautier M. Moncuquet N. Meyer-Vernet S. Hoang R. Manning 《Astrophysics and Space Science》2001,277(1-2):309-311
We present the method of plasma diagnostics by quasi-thermal noise spectroscopy and show examples of application in the solar
wind and the Earth's plasmasphere. Using only an electric antenna and a radio receiver, diagnostics of various space environments
(magnetized or not) can be obtained in situ. Because of its accuracy, this technique can be used to cross-check other plasma sensors.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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