O. Limousin
A5010171470- Advanced Semiconductor Detectors and Materials
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Advanced X-ray and CT Imaging
- Nuclear Physics and Applications
- CCD and CMOS Imaging Sensors
- Solar and Space Plasma Dynamics
- Astrophysical Phenomena and Observations
- Dark Matter and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Astro and Planetary Science
- Astronomy and Astrophysical Research
- Adaptive optics and wavefront sensing
- Satellite Image Processing and Photogrammetry
- Infrared Target Detection Methodologies
- Medical Imaging Techniques and Applications
- Calibration and Measurement Techniques
- Stellar, planetary, and galactic studies
- Spacecraft Design and Technology
- Particle physics theoretical and experimental studies
- Geomagnetism and Paleomagnetism Studies
- Ionosphere and magnetosphere dynamics
- Radiation Therapy and Dosimetry
- Pulsars and Gravitational Waves Research
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2015-2024
CEA Paris-Saclay
2015-2024
Université Paris-Saclay
2016-2024
Institut de Recherche sur les Lois Fondamentales de l'Univers
2014-2024
Astrophysique, Instrumentation et Modélisation
2012-2024
Université Paris Cité
2015-2024
Centre National de la Recherche Scientifique
2015-2024
Sorbonne Paris Cité
2020-2022
Délégation Paris 7
2015-2022
CEA Paris-Saclay - Etablissement de Saclay
2004-2018
For the first time in history of high energy astronomy, a large CdTe gamma-ray camera is operating space. ISGRI low-energy IBIS telescope on board INTEGRAL satellite. This paper details its design and in-flight behavior performances. Having sensitive area 2621 cm$^2$ with spatial resolution 4.6 mm, low threshold around 12 keV an $\sim$ 8% at 60 keV, shows absolutely no signs degradation after 9 months orbit. All aspects scientific performance are fully nominal, particular observed background...
The International Axion Observatory (IAXO) will be a forth generation axion helioscope. As its primary physics goal, IAXO look for axions or axion-like particles (ALPs) originating in the Sun via Primakoff conversion of solar plasma photons. In terms signal-to-noise ratio, about 4–5 orders magnitude more sensitive than CAST, currently most powerful helioscope, reaching sensitivity to axion-photon couplings down few × 10−12 GeV−1 and thus probing large fraction unexplored ALP parameter space....
Aims. The Spectrometer Telescope for Imaging X-rays (STIX) on Solar Orbiter is a hard X-ray imaging spectrometer, which covers the energy range from 4 to 150 keV. STIX observes bremsstrahlung emissions solar flares and therefore provides diagnostics of hottest (⪆10 MK) flare plasma while quantifying location, spectrum, content flare-accelerated nonthermal electrons. Methods. To accomplish this, applies an indirect bigrid Fourier technique using set tungsten grids (at pitches 0.038 1 mm) in...
After decades of observations solar energetic particles from space-based observatories, relevant questions on particle injection, transport, and acceleration remain open. To address these scientific topics, accurate measurements the properties in inner heliosphere are needed. In this paper we describe Energetic Particle Detector (EPD), an instrument suite that is part payload aboard Solar Orbiter mission. will approach Sun as close 0.28 au provide extra-ecliptic beyond ∼30° heliographic...
We review the physics potential of a next generation search for solar axions: International Axion Observatory (IAXO) . Endowed with sensitivity to discover axion-like particles (ALPs) coupling photons as small gaγ∼ 10−12 GeV−1, or electrons gae∼10−13, IAXO has find QCD axion in 1 meV∼1 eV mass range where it solves strong CP problem, can account cold dark matter Universe and be responsible anomalous cooling observed number stellar systems. At same time, will have enough detect lower axions...
A bstract This article describes BabyIAXO, an intermediate experimental stage of the International Axion Observatory (IAXO), proposed to be sited at DESY. IAXO is a large-scale axion helioscope that will look for axions and axion-like particles (ALPs), produced in Sun, with unprecedented sensitivity. BabyIAXO conceived test all subsystems (magnet, optics detectors) relevant scale final system thus serve as prototype IAXO, but same time fully-fledged physics reach itself, potential discovery....
Automatic and fast identification of gamma-ray-emitting radionuclides is a challenge in the field nuclear safety, especially case emergency, since it requires complex calculations often knowledge experts to interpret data. We present development an automatic method based on convolutional neural networks (CNNs) as new tool analyze gamma-ray spectra real time, which uses not only photoelectric peaks but also extracts all discriminant features spectrum, such Compton structures, for instance....
Solar Orbiter strives to unveil how the Sun controls and shapes heliosphere fills it with energetic particle radiation. To this end, its Energetic Particle Detector (EPD) has now been in operation, providing excellent data, for just over a year. EPD measures suprathermal particles energy range from few keV up (near-) relativistic energies (few MeV electrons about 500 MeV/nuc ions). We present an overview of initial results first year operations we provide assessment issues limitations....
The Spectrometer and Telescope for Imaging X-rays (STIX) on board Solar Orbiter observes solar X-ray emission in the range of 4 – 150 keV produces spectra images flares over a wide flare magnitudes. During nominal operation, STIX continuously generates data. A constant data flow requires fully automated data-processing pipelines to process analyze data, platform manage, visualize, distribute products scientific community. Data Center has been built fulfill these needs. In this paper,...
Context. The Spectrometer/Telescope for Imaging X-rays (STIX) is the hard X-ray instrument onboard Solar Orbiter designed to observe solar flares over a broad range of flare sizes. Aims. We report first STIX observations microflares recorded during commissioning phase in order investigate performance at its detection limit. Methods. uses imaging spectroscopy between 4–150 keV diagnose hottest plasma and related nonthermal electrons. This result paper focuses on temporal spectral evolution...
Since few years, our group is developing a family of ASICs for space applications, named IDeF-X Imaging Detector Front-end. HD the new member family. It has been optimized readout 16 x pixels CdTe or CdZnTe pixelated detectors to build low power Caliste 256 module. This micro gamma-camera will be elementary unit MAC SI (Modular Assembly Spectro Imager) camera: A 2048-pixels 8 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> gamma...
Simbol-X is a hard X-ray mission, operating in the ~ 0.5-80 keV range, proposed as collaboration between French and Italian space agencies with participation of German laboratories for launch 2013. Relying on two spacecraft formation flying configuration, uses first time 20-30 m focal length mirror to focus X-rays energy above 10 keV, resulting over orders magnitude improvement angular resolution sensitivity range respect non-focusing techniques. The revolutionary instrumental capabilities...
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A prototype 64 pixel miniature camera has been designed and tested for the Simbol-X hard X-ray observatory to be flown on joint CNES-ASI space mission in 2014. This device is called Caliste 64. It a high performance spectro-imager with event time-tagging capability, able detect photons between 2 keV 250 keV. assembly of 1 or mm thick CdTe detector mounted top readout module. detectors equipped...
Caliste HD is the last member of family Cd(Zn)Te micro-cameras for space applications. This hybrid component made assembly one 16 × pixel detector and eight analog front-end ASIC named IDeF-X equipped with 32 spectroscopic channels. The pixels are 625 μm pitch surrounded by a 20 wide guard ring. new generation has advantage having power consumption 4 times lower as previous version (0.2 W full device) offers possibility to extend dynamic range from 250 keV 1 MeV. technology fully compliant...