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T. Camus

Bio: T. Camus is an academic researcher from University of Toulouse. The author has contributed to research in topics: Electrostatic analyzer & Magnetosphere. The author has an hindex of 3, co-authored 5 publications receiving 1473 citations.

Papers
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Journal ArticleDOI
TL;DR: The Cluster Ion Spectrometry (CIS) experiment as discussed by the authors measured the full, three-dimensional ion distribution of the major magnetospheric ions (H+, He+, He++, and O+) from the thermal energies to about 40 keV/e.
Abstract: . On board the four Cluster spacecraft, the Cluster Ion Spectrometry (CIS) experiment measures the full, three-dimensional ion distribution of the major magnetospheric ions (H+, He+, He++, and O+) from the thermal energies to about 40 keV/e. The experiment consists of two different instruments: a COmposition and DIstribution Function analyser (CIS1/CODIF), giving the mass per charge composition with medium (22.5°) angular resolution, and a Hot Ion Analyser (CIS2/HIA), which does not offer mass resolution but has a better angular resolution (5.6°) that is adequate for ion beam and solar wind measurements. Each analyser has two different sensitivities in order to increase the dynamic range. First tests of the instruments (commissioning activities) were achieved from early September 2000 to mid January 2001, and the operation phase began on 1 February 2001. In this paper, first results of the CIS instruments are presented showing the high level performances and capabilities of the instruments. Good examples of data were obtained in the central plasma sheet, magnetopause crossings, magnetosheath, solar wind and cusp measurements. Observations in the auroral regions could also be obtained with the Cluster spacecraft at radial distances of 4–6 Earth radii. These results show the tremendous interest of multispacecraft measurements with identical instruments and open a new area in magnetospheric and solar wind-magnetosphere interaction physics. Key words. Magnetospheric physics (magnetopause, cusp and boundary layers; magnetopheric configuration and dynamics; solar wind - magnetosphere interactions)

1,209 citations

Book ChapterDOI
TL;DR: The Cluster Ion Spectrometry (CIS) experiment is a comprehensive ionic plasma spec-trometry package on-board the four Cluster spacecraft capable of obtaining full three-dimensional ion distributions with good time resolution (one spacecraft spin) with mass per charge composition determination as mentioned in this paper.
Abstract: The Cluster Ion Spectrometry (CIS) experiment is a comprehensive ionic plasma spec-trometry package on-board the four Cluster spacecraft capable of obtaining full three-dimensional ion distributions with good time resolution (one spacecraft spin) with mass per charge composition determination. The requirements to cover the scientific objectives cannot be met with a single instrument. The CIS package therefore consists of two different instruments, a Hot Ion Analyser (HIA) and a time-of-flight ion Composition and Distribution Function analyser (CODIF), plus a sophisticated dual-processor-based instrument-control and Data-Processing System (DPS), which permits extensive on-board data-processing. Both analysers use symmetric optics resulting in continuous, uniform, and well-characterised phase space coverage. CODIF measures the distributions of the major ions (H+, He+, He++, and O+) with energies from -0 to 40 keV/e with medium (22.5°) angular resolution and two different sensitivities. HIA does not offer mass resolution but, also having two different sensitivities, increases the dynamic range, and has an angular resolution capability (5.6° × 5.6°) adequate for ion-beam and solar-wind measurements.

257 citations

Book ChapterDOI
TL;DR: In this article, a toroidal top-hat electrostatic analyzer with instantaneous acceptance of ions over 360° in polar angle was used for the first time to determine the 3D distribution functions of individual ion species within 1 2 or 1 spin period.
Abstract: A similar time-of-flight plasma analyzer system will be flown as CODIF (COmposition and Dlstribution Function analyzer) on the four Cluster spacecraft, as ESIC (Equator-S Ion Composition instrument) on Equator-S, and as TEAMS (Time-of-flight Energy Angle Mass Spectrograph) on FAST. These instruments will for the first time allow the 3-dimensional distribution functions of individual ion species to be determined within 1/2 or 1 spin period. This will be crucial for the study of selective energization processes in various regions of the magnetosphere. The sensor consists of a toroidal top-hat electrostatic analyzer with instantaneous acceptance of ions over 360° in polar angle. For Cluster and Equator-S this range is subdivided into two halves with geometric factors different by a factor of 100 in order to cope with the wide dynamic range of fluxes in the magnetosphere. For FAST the time resolution is increased by a factor of two to focus on fast auroral phenomena by using both halves simultaneously. After post-acceleration of the incoming ions by up to 25 kV, a time-of-flight mass spectrograph discriminates the individual species. It has been demonstrated in calibration runs that the instruments can easily separate H + , He 2+ , He + , O + and for energies after post-acceleration of 3 20 keV even O 2 + molecules. On board discrimination, accumulation, and moment computation allow efficient retrieval of the data stream.

50 citations

Journal ArticleDOI
TL;DR: The Athena X-ray Integral Unit (X-IFU) as discussed by the authors is the high-resolution Xray spectrometer, studied since 2015 for flying in the mid-30s on the Athena space Xray Observatory, a versatile observatory designed to address the Hot and Energetic Universe science theme.
Abstract: The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer, studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory, a versatile observatory designed to address the Hot and Energetic Universe science theme, selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), it aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over an hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (including the X-IFU cryostat and the cooling chain), due to an unanticipated cost overrun of Athena. In this paper, after illustrating the breakthrough capabilities of the X-IFU, we describe the instrument as presented at its SRR, browsing through all the subsystems and associated requirements. We then show the instrument budgets, with a particular emphasis on the anticipated budgets of some of its key performance parameters. Finally we briefly discuss on the ongoing key technology demonstration activities, the calibration and the activities foreseen in the X-IFU Instrument Science Center, and touch on communication and outreach activities, the consortium organisation, and finally on the life cycle assessment of X-IFU aiming at minimising the environmental footprint, associated with the development of the instrument. Thanks to the studies conducted so far on X-IFU, it is expected that along the design-to-cost exercise requested by ESA, the X-IFU will maintain flagship capabilities in spatially resolved high resolution X-ray spectroscopy, enabling most of the original X-IFU related scientific objectives of the Athena mission to be retained. (abridged).

20 citations

Proceedings ArticleDOI
20 May 2019
TL;DR: The Active Monitor Box of Electrostatic Risks (AMBER) as discussed by the authors is a double-head thermal ion and ion electrostatic analyzer (energy range 0-30 keV) that was launched onboard the Jason-3 spacecraft in 2016.
Abstract: The Active Monitor Box of Electrostatic Risks (AMBER) is a double-head thermal electron and ion electrostatic analyzer (energy range 0–30 keV) that was launched onboard the Jason-3 spacecraft in 2016. The next generation AMBER instrument, for which a first prototype was developed and then calibrated at the end of 2017, constitutes a significant evolution that is based on a single head to measure both species alternatively. The instrument developments focused on several new sub-systems (front-end electronics, highvoltage electronics, mechanical design) that permit to reduce instrument resources down to ∼ 1 kg and 1.5 W. AMBER is designed as a generic radiation monitor with a twofold purpose: (1) measure magnetospheric thermal ion and electron populations in the range 0–35 keV, with significant scientific potential (e.g., plasmasphere, ring current, plasma sheet), and (2) monitor spacecraft electrostatic charging and the plasma populations responsible for it, for electromagnetic cleanliness and operational purposes.

1 citations


Cited by
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Journal ArticleDOI
TL;DR: The Cluster Ion Spectrometry (CIS) experiment as discussed by the authors measured the full, three-dimensional ion distribution of the major magnetospheric ions (H+, He+, He++, and O+) from the thermal energies to about 40 keV/e.
Abstract: . On board the four Cluster spacecraft, the Cluster Ion Spectrometry (CIS) experiment measures the full, three-dimensional ion distribution of the major magnetospheric ions (H+, He+, He++, and O+) from the thermal energies to about 40 keV/e. The experiment consists of two different instruments: a COmposition and DIstribution Function analyser (CIS1/CODIF), giving the mass per charge composition with medium (22.5°) angular resolution, and a Hot Ion Analyser (CIS2/HIA), which does not offer mass resolution but has a better angular resolution (5.6°) that is adequate for ion beam and solar wind measurements. Each analyser has two different sensitivities in order to increase the dynamic range. First tests of the instruments (commissioning activities) were achieved from early September 2000 to mid January 2001, and the operation phase began on 1 February 2001. In this paper, first results of the CIS instruments are presented showing the high level performances and capabilities of the instruments. Good examples of data were obtained in the central plasma sheet, magnetopause crossings, magnetosheath, solar wind and cusp measurements. Observations in the auroral regions could also be obtained with the Cluster spacecraft at radial distances of 4–6 Earth radii. These results show the tremendous interest of multispacecraft measurements with identical instruments and open a new area in magnetospheric and solar wind-magnetosphere interaction physics. Key words. Magnetospheric physics (magnetopause, cusp and boundary layers; magnetopheric configuration and dynamics; solar wind - magnetosphere interactions)

1,209 citations

Journal ArticleDOI
Craig J. Pollock1, T. E. Moore1, A. D. Jacques1, James L. Burch2, U. Gliese1, Yoshifumi Saito, T. Omoto, Levon A. Avanov1, Levon A. Avanov3, A. C. Barrie1, Victoria N. Coffey4, John C. Dorelli1, Daniel J. Gershman1, Daniel J. Gershman3, Daniel J. Gershman5, Barbara L. Giles1, T. Rosnack1, C. Salo1, Shoichiro Yokota, M. L. Adrian1, C. Aoustin, C. Auletti1, S. Aung1, V. Bigio1, N. Cao1, Michael O. Chandler4, Dennis J. Chornay3, Dennis J. Chornay1, K. Christian1, George Clark6, George Clark1, George Clark7, Glyn Collinson7, Glyn Collinson1, T. Corris1, A. De Los Santos2, R. Devlin1, T. Diaz2, T. Dickerson1, C. Dickson1, A. Diekmann4, F. Diggs1, C. Duncan1, A. Figueroa-Vinas1, C. Firman1, M. Freeman2, N. Galassi1, K. Garcia1, G. Goodhart2, D. Guererro2, J. Hageman1, Jennifer Hanley2, E. Hemminger1, Matthew Holland1, M. Hutchins2, T. James1, W. Jones1, S. Kreisler1, Joseph Kujawski8, Joseph Kujawski1, V. Lavu1, J. V. Lobell1, E. LeCompte, A. Lukemire, Elizabeth MacDonald1, Al. Mariano1, Toshifumi Mukai, K. Narayanan1, Q. Nguyan1, M. Onizuka1, William R. Paterson1, S. Persyn2, Benjamin M. Piepgrass2, F. Cheney1, A. C. Rager7, A. C. Rager1, T. Raghuram1, A. Ramil1, L. S. Reichenthal1, H. Rodriguez2, Jean-Noël Rouzaud, A. Rucker1, Marilia Samara1, Jean-André Sauvaud, D. Schuster1, M. Shappirio1, K. Shelton1, D. Sher1, David Smith1, Kerrington D. Smith2, S. E. Smith1, S. E. Smith7, D. Steinfeld1, R. Szymkiewicz1, K. Tanimoto, J. Taylor2, Compton J. Tucker1, K. Tull1, A. Uhl1, J. Vloet2, P. Walpole2, P. Walpole1, S. Weidner2, D. White2, G. E. Winkert1, P.-S. Yeh1, M. Zeuch1 
TL;DR: The Fast Plasma Investigation (FPI) was developed for flight on the Magnetospheric Multiscale (MMS) mission to measure the differential directional flux of magnetospheric electrons and ions with unprecedented time resolution to resolve kinetic-scale plasma dynamics as mentioned in this paper.
Abstract: The Fast Plasma Investigation (FPI) was developed for flight on the Magnetospheric Multiscale (MMS) mission to measure the differential directional flux of magnetospheric electrons and ions with unprecedented time resolution to resolve kinetic-scale plasma dynamics. This increased resolution has been accomplished by placing four dual 180-degree top hat spectrometers for electrons and four dual 180-degree top hat spectrometers for ions around the periphery of each of four MMS spacecraft. Using electrostatic field-of-view deflection, the eight spectrometers for each species together provide 4pi-sr field-of-view with, at worst, 11.25-degree sample spacing. Energy/charge sampling is provided by swept electrostatic energy/charge selection over the range from 10 eV/q to 30000 eV/q. The eight dual spectrometers on each spacecraft are controlled and interrogated by a single block redundant Instrument Data Processing Unit, which in turn interfaces to the observatory’s Instrument Suite Central Instrument Data Processor. This paper describes the design of FPI, its ground and in-flight calibration, its operational concept, and its data products.

1,038 citations

Journal ArticleDOI
TL;DR: It is shown that the electron Larmor radius plays the role of a dissipation scale in space plasma turbulence and the spectra form a quasiuniversal spectrum following the Kolmogorov's law at MHD scales.
Abstract: To investigate the universality of magnetic turbulence in space plasmas, we analyze seven time periods in the free solar wind under different plasma conditions. Three instruments on Cluster spacecraft operating in different frequency ranges give us the possibility to resolve spectra up to 300 Hz. We show that the spectra form a quasiuniversal spectrum following the Kolmogorov's law $\ensuremath{\sim}{k}^{\ensuremath{-}5/3}$ at MHD scales, a $\ensuremath{\sim}{k}^{\ensuremath{-}2.8}$ power law at ion scales, and an exponential $\ensuremath{\sim}\mathrm{exp} [\ensuremath{-}\sqrt{k{\ensuremath{\rho}}_{e}}]$ at scales $k{\ensuremath{\rho}}_{e}\ensuremath{\sim}[0.1,1]$, where ${\ensuremath{\rho}}_{e}$ is the electron gyroradius. This is the first observation of an exponential magnetic spectrum in space plasmas that may indicate the onset of dissipation. We distinguish for the first time between the role of different spatial kinetic plasma scales and show that the electron Larmor radius plays the role of a dissipation scale in space plasma turbulence.

437 citations

Journal ArticleDOI
TL;DR: In this paper, a flow burst was associated with a clear dipolarization ahead of the high-speed part of the predominantly Earthward directed flow, and the authors found that a ∼2000 km thick dipolarisation front moves Earthward and dawnward with a speed of ∼77 km/s.
Abstract: [1] In this paper we study a flow burst event which took place during enhanced geomagnetic activity on July 22, 2001, when Cluster was located in the postmidnight magnetotail. The flow burst was associated with a clear dipolarization ahead of the high-speed part of the predominantly Earthward directed flow. Based on the analysis of the four spacecraft data, we found that a ∼2000 km thick dipolarization front moves Earthward and dawnward with a speed of ∼77 km/s. The plasma before this front is deflected, consistent with the plasma ahead of a localized plasma bubble centered at midnight side being pushed aside by the moving obstacle. The main body of the high-speed flow is directed mainly parallel to the dipolarization front. These observations indicate that the evolution of the dipolarization front across the tail is directly coupled with the fast flow.

371 citations

Journal ArticleDOI
Vassilis Angelopoulos1, P. Cruce1, Alexander Drozdov1, Eric Grimes1, N. Hatzigeorgiu2, D. A. King2, Davin Larson2, James W. Lewis2, J. M. McTiernan2, D. A. Roberts3, C. L. Russell1, Tomoaki Hori4, Yoshiya Kasahara5, Atsushi Kumamoto6, Ayako Matsuoka, Yukinaga Miyashita7, Yoshizumi Miyoshi4, I. Shinohara, Mariko Teramoto4, Jeremy Faden, Alexa Halford8, Matthew D. McCarthy9, Robyn Millan10, John Sample11, David M. Smith12, L. A. Woodger10, Arnaud Masson, A. A. Narock3, Kazushi Asamura, T. F. Chang4, C. Y. Chiang13, Yoichi Kazama14, Kunihiro Keika15, S. Matsuda4, Tomonori Segawa4, Kanako Seki15, Masafumi Shoji4, Sunny W. Y. Tam13, Norio Umemura4, B. J. Wang14, B. J. Wang16, Shiang-Yu Wang14, Robert J. Redmon17, Juan V. Rodriguez18, Juan V. Rodriguez17, Howard J. Singer17, Jon Vandegriff19, S. Abe20, Masahito Nose21, Masahito Nose4, Atsuki Shinbori4, Yoshimasa Tanaka22, S. UeNo21, L. Andersson23, P. Dunn2, Christopher M. Fowler23, Jasper Halekas24, Takuya Hara2, Yuki Harada21, Christina O. Lee2, Robert Lillis2, David L. Mitchell2, Matthew R. Argall25, Kenneth R. Bromund3, James L. Burch26, Ian J. Cohen19, Michael Galloy27, Barbara L. Giles3, Allison Jaynes24, O. Le Contel28, Mitsuo Oka2, T. D. Phan2, Brian Walsh29, Joseph Westlake19, Frederick Wilder23, Stuart D. Bale2, Roberto Livi2, Marc Pulupa2, Phyllis Whittlesey2, A. DeWolfe23, Bryan Harter23, E. Lucas23, U. Auster30, John W. Bonnell2, Christopher Cully31, Eric Donovan31, Robert E. Ergun23, Harald U. Frey2, Brian Jackel31, A. Keiling2, Haje Korth19, J. P. McFadden2, Yukitoshi Nishimura29, Ferdinand Plaschke32, P. Robert28, Drew Turner8, James M. Weygand1, Robert M. Candey3, R. C. Johnson3, T. Kovalick3, M. H. Liu3, R. E. McGuire3, Aaron Breneman33, Kris Kersten33, P. Schroeder2 
TL;DR: The SPEDAS development history, goals, and current implementation are reviewed, and its “modes of use” are explained with examples geared for users and its technical implementation and requirements with software developers in mind are outlined.
Abstract: With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform ( www.spedas.org ), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have “crib-sheets,” user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer’s Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its “modes of use” with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans.

371 citations