Coordinated Study on Solar Wind Turbulence During the Venus-Express, ACE and Ulysses Alignment of August 2007

At the end of August 2007, Venus, Earth and Ulysses were aligned within a few degrees. This unusual event gives the opportunity to attempt a coordinated study on the radial evolution of solar wind turbulence and coronal transients like CMEs between 0.7 and 1.4 AU. Interplanetary magnetic field data and moments of proton velocity distribution function such as density, speed and temperature are required for this programme and will be provided by ACE at Earth, Venus Express at Venus and Ulysses at 1.4 AU. This project has been recently proposed as a Coordinated Investigation Programme (CIP35) for the International Heliophysical Year.     

SVM后验概率结合改进多尺度MRF的遥感影像分割方法

采用SVM方法估计似然概率,克服了混合高斯模型对观测场建模不准确的问题;通过改进的多尺度MRF模型,在标记场建模时充分考虑了各尺度之间和同一尺度内的相关性,进一步准确描述了标记场的统计特性.最后利用改进的建模方法,在序贯最大后验概率估计算法框架下进行影像分割.通过对人工合成影像和实际遥感影像的分割实验结果分析,证明了本文方法能够有效提高分割效果.     

Planetary Wave Periods in <Emphasis Type="Italic">foF</Emphasis>2 Time Variations Based on Winter Data from Kaliningrad Station in 2008−2010

The study presents the results of the analysis of the F2-layer critical frequency variations obtained for the winter periods of 2008–2010, during which sudden stratospheric warmings were observed. The data were obtained at Kaliningrad ionospheric station (54.6° N, 20° E) with the Parus digital ionosonde in standard sounding mode. The mean daily foF2 values were used in the analysis. The results of spectral analysis based on continuous wavelet transform showed that, during all of the warmings that occurred in 2008–2010, the foF2 time variations demonstrated the presence of wave processes with periods of approximately 5?6 days, as well as more extended processes with periods of ~10?13 and 23?30 days. These periods coincide with the characteristic periods of planetary waves observed in the mesosphere during sudden stratospheric warmings, while the 13- and 30-day periods can be conditioned by the influence of the Sun.     

桂东7～9月西风系统暴雨短期预报方法

利用近10a的报文资料,计算7～9月西风系统暴雨出现前24h,与梧州站以西、北相邻的25个探空站相应的28个物理量场,利用相关分析,筛选出能较好地反映西风系统暴雨天气特征的若干物理量场,依据动力相似的基本原理,作出未来24h桂东暴雨落区预报.     

A review of the LATEX project: mesoscale to submesoscale processes in a coastal environment

The main objective of the LAgrangian Transport EXperiment (LATEX) project was to study the influence of coastal mesoscale and submesoscale physical processes on circulation dynamics, cross-shelf exchanges, and biogeochemistry in the western continental shelf of the Gulf of Lion, Northwestern Mediterranean Sea. LATEX was a five-year multidisciplinary project based on the combined analysis of numerical model simulations and multi-platform field experiments. The model component included a ten-year realistic 3D numerical simulation, with a 1 km horizontal resolution over the gulf, nested in a coarser 3 km resolution model. The in situ component involved four cruises, including a large-scale multidisciplinary campaign with two research vessels in 2010. This review concentrates on the physics results of LATEX, addressing three main subjects: (1) the investigation of the mesoscale to submesoscale processes. The eddies are elliptic, baroclinic, and anticyclonic; the strong thermal and saline front is density compensated. Their generation processes are studied; (2) the development of sampling strategies for their direct observations. LATEX has implemented an adaptive strategy Lagrangian tool, with a reference software available on the web, to perform offshore campaigns in a Lagrangian framework; (3) the quantification of horizontal mixing and cross-shelf exchanges. Lateral diffusivity coefficients, calculated in various ways including a novel technique, are in the range classically encountered for their associated scales. Cross-shelf fluxes have been calculated, after retrieving the near-inertial oscillation contribution. Further perspectives are discussed, especially for the ongoing challenge of studying submesoscale features remotely and from in situ data.     

The particle background of the <Emphasis Type="Italic">X-IFU</Emphasis> instrument

In this paper we are going to review the latest estimates for the particle background expected on the X-IFU instrument onboard of the ATHENA mission. The particle background is induced by two different particle populations: the so called “soft protons” and the Cosmic rays. The first component is composed of low energy particles (< 100s keV) that get funnelled by the mirrors towards the focal plane, losing part of their energy inside the filters and inducing background counts inside the instrument sensitivity band. The latter component is induced by high energy particles (> 100 MeV) that possess enough energy to cross the spacecraft and reach the detector from any direction, depositing a small fraction of their energy inside the instrument. Both these components are estimated using Monte Carlo simulations and the latest results are presented here.     

The Cryogenic AntiCoincidence detector for ATHENA X-IFU: a scientific assessment of the observational capabilities in the hard X-ray band

ATHENA is a large X-ray observatory, planned to be launched by ESA in 2028 towards an L2 orbit. One of the two instruments of the payload is the X-IFU: a cryogenic spectrometer based on a large array of TES microcalorimeters, able to perform integral field spectrography in the 0.2–12 keV band (2.5 eV FWHM at 6 keV). The X-IFU sensitivity is highly degraded by the particle background expected in the L2 orbit, which is induced by primary protons of both galactic and solar origin, and mostly by secondary electrons. To reduce the particle background level and enable the mission science goals, the instrument incorporates a Cryogenic AntiCoincidence detector (CryoAC). It is a 4 pixel TES based detector, placed < 1 mm below the main array. In this paper we report a scientific assessment of the CryoAC observational capabilities in the hard X-ray band (E > 10 keV). The aim of the study has been to understand if the present detector design can be improved in order to enlarge the X-IFU scientific capability on an energy band wider than the TES array. This is beyond the CryoAC baseline, being this instrument aimed to operate as anticoincidence particle detector and not conceived to perform X-ray observations.     

Tectonics and metallogeny of the junction zone between the North Asian craton and Pacific tectonic belt

The tectonics and metallogeny of the junction zone between the North Asian craton and Pacific tectonic belt are considered. This zone is characterized by a wide variety of structures superposed on the metamorphic basement, which was formed in the course of a multistage geologic development of the craton from the Precambrian to the Cenozoic. They are related to the craton evolution and its response to the collision and subduction processes in the adjacent orogenic belt, processes in the passive and active continental margins, and plume magmatism. The geological structure of the region includes blocks of metamorphic rocks of the Aldan–Stanovoi shield, Paleoproterozoic volcanogenic troughs, Mesoproterozoic–Neoproterozoic and Early Paleozoic structures of the platform cover, Late Paleozoic volcanic and terrigenous troughs, structures of the Late Mesozoic Okhotsk–Chukotka volcanic belt of the active continental margin, and Late Cretaceous riftogenic structures formed in response to plume magmatism. In total, six metallogenic epochs are recognized in the development of ore mineralization: Archean–Early Paleoproterozoic, Late Paleoproterozoic, Mesoproterozoic, Neoproterozoic, Late Paleozoic, and Late Mesozoic. The minerageny of the junction zone between the craton and Pacific belt is highly diversified, being characterized by distinct evolution in time and space. Each development stage features its own set of mineral resources.