Conception of a near-IR spectrometer for ground-based observations of massive stars

In our contribution, we outline the different steps in the design of a fiber-fed spectrographic instrument that intends to observe massive stars. Starting from the derivation of theoretical relationships from the scientific requirements and telescope characteristics, the entire optical design of the spectrograph is presented. Specific optical elements, such as a toroidal lens, are introduced to improve the instrument’s performances. Then, the verification of predicted optical performances is investigated through optical analyses such as resolution checking. Eventually, the star positioning system onto the central fiber core is explained.Massive stars: drivers of the evolution of the Univers

The Solar Particle Acceleration Radiation and Kinetics (SPARK) Mission Concept

© 2023by the authors. Licensee MDPI, Basel, Switzerland. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Particle acceleration is a fundamental process arising in many astrophysical objects, including active galactic nuclei, black holes, neutron stars, gamma-ray bursts, accretion disks, solar and stellar coronae, and planetary magnetospheres. Its ubiquity means energetic particles permeate the Universe and influence the conditions for the emergence and continuation of life. In our solar system, the Sun is the most energetic particle accelerator, and its proximity makes it a unique laboratory in which to explore astrophysical particle acceleration. However, despite its importance, the physics underlying solar particle acceleration remain poorly understood. The SPARK mission will reveal new discoveries about particle acceleration through a uniquely powerful and complete combination of γ-ray, X-ray, and EUV imaging and spectroscopy at high spectral, spatial, and temporal resolutions. SPARK’s instruments will provide a step change in observational capability, enabling fundamental breakthroughs in our understanding of solar particle acceleration and the phenomena associated with it, such as the evolution of solar eruptive events. By providing essential diagnostics of the processes that drive the onset and evolution of solar flares and coronal mass ejections, SPARK will elucidate the underlying physics of space weather events that can damage satellites and power grids, disrupt telecommunications and GPS navigation, and endanger astronauts in space. The prediction of such events and the mitigation of their potential impacts are crucial in protecting our terrestrial and space-based infrastructure.Peer reviewe

The Solar Particle Acceleration Radiation and Kinetics (SPARK) mission concept

Particle acceleration is a fundamental process arising in many astrophysical objects, including active galactic nuclei, black holes, neutron stars, gamma-ray bursts, accretion disks, solar and stellar coronae, and planetary magnetospheres. Its ubiquity means energetic particles permeate the Universe and influence the conditions for the emergence and continuation of life. In our solar system, the Sun is the most energetic particle accelerator, and its proximity makes it a unique laboratory in which to explore astrophysical particle acceleration. However, despite its importance, the physics underlying solar particle acceleration remain poorly understood. The SPARK mission will reveal new discoveries about particle acceleration through a uniquely powerful and complete combination of γ-ray, X-ray, and EUV imaging and spectroscopy at high spectral, spatial, and temporal resolutions. SPARK’s instruments will provide a step change in observational capability, enabling fundamental breakthroughs in our understanding of solar particle acceleration and the phenomena associated with it, such as the evolution of solar eruptive events. By providing essential diagnostics of the processes that drive the onset and evolution of solar flares and coronal mass ejections, SPARK will elucidate the underlying physics of space weather events that can damage satellites and power grids, disrupt telecommunications and GPS navigation, and endanger astronauts in space. The prediction of such events and the mitigation of their potential impacts are crucial in protecting our terrestrial and space-based infrastructure

The Solar Particle Acceleration Radiation and Kinetics (SPARK) Mission Concept

Particle acceleration is a fundamental process arising in many astrophysical objects, including active galactic nuclei, black holes, neutron stars, gamma-ray bursts, accretion disks, solar and stellar coronae, and planetary magnetospheres. Its ubiquity means energetic particles permeate the Universe and influence the conditions for the emergence and continuation of life. In our solar system, the Sun is the most energetic particle accelerator, and its proximity makes it a unique laboratory in which to explore astrophysical particle acceleration. However, despite its importance, the physics underlying solar particle acceleration remain poorly understood. The SPARK mission will reveal new discoveries about particle acceleration through a uniquely powerful and complete combination of γ-ray, X-ray, and EUV imaging and spectroscopy at high spectral, spatial, and temporal resolutions. SPARK’s instruments will provide a step change in observational capability, enabling fundamental breakthroughs in our understanding of solar particle acceleration and the phenomena associated with it, such as the evolution of solar eruptive events. By providing essential diagnostics of the processes that drive the onset and evolution of solar flares and coronal mass ejections, SPARK will elucidate the underlying physics of space weather events that can damage satellites and power grids, disrupt telecommunications and GPS navigation, and endanger astronauts in space. The prediction of such events and the mitigation of their potential impacts are crucial in protecting our terrestrial and space-based infrastructure

Conception d'un spectrographe proche-infrarouge pour l'observation des étoiles massives

This research contribution intends to introduce the conception of a new fiber-fed spectrograph, called NƎSIE, that operates in the near-infrared domain. This PhD thesis was part of a research project led by Prof. Rauw which focuses on massive stars. The final location of NƎSIE will be the TIGRE telescope located in La Luz, Mexico. The observational data provided by this instrument will help several research groups from the University of Liège to study massive stars. In particularly, evolution models will be improved through the comparison of the collected spectra with theoretical models. This collaboration will therefore contribute to a better understanding of massive stars and the mechanisms that take place within these extraordinary objects.Ce travail de recherche a pour intention de présenter la conception d’un nouveau spectrographe, appelé NƎSIE, alimenté par fibres optiques qui opère dans le domaine proche-infrarouge. Cette thèse de doctorat faisait partie d’un projet de recherche mené par le Prof. Rauw centré sur les étoiles massives. La destination finale de NƎSIE sera le télescope TIGRE qui se trouve à La Luz au Mexique. Les données observationnelles fournies par cet instrument aideront plusieurs groupes de recherche de l’Université de Liège à étudier les étoiles massives. Plus particulièrement, des modèles d’évolution seront améliorés au travers de comparaisons entre les spectres collectés et les modèles théoriques. Cette collaboration contribuera dès lors à une meilleure compréhension des étoiles massives et des phénomènes qui se déroulent au sein de ces objets extraordinaires.Massive stars: drivers of the evolution of the univers

Design, assembly and test of a near-infrared spectrograph for the TIGRE telescope

The presentation introduces the different major steps of the design of a near-infrared spectrograph that will be installed at the TIGRE telescope, Mexico.Massive stars: drivers of the evolution of the Univers

Feasibility of a UV imager onboard a Cubesat platform

This Master thesis presents the feasibility study of an ultraviolet imager onboard a Cubesat platform. The goal is to observe the Io's torus with the help of a triple unit Cubesat. Similar projects are studied to identify possible components for the mission. A mission analysis is carried out to highlight suitable intervals of time to observe the Io's torus when considering different orbits. Then optical design processes are performed to obtain a telescope that fits in the Cubesat platform. Eventually a final design that fulfils all the scientific requirements is introduced and a few perspectives are proposed for the future studies

Conception of a near-infrared spectrometer for ground-based observations of massive stars

In our contribution, we outline the different steps in the design of a fiber-fed spectrographic instrument for stellar astrophysics. Starting from the derivation of theoretical relationships from the scientific requirements and telescope characteristics, the entire optical design of the spectrograph is presented. Specific optical elements, such as a toroidal lens, are introduced to improve the instrument’s efficiency. Then the verification of predicted optical performances is investigated through optical analyses, such as resolution checking.Massive stars: drivers of the evolution of the Univers

Feasibility study of a UV photometer on-board a 3 CubeSat for the study of bright massive stars

Following the amazing progresses in miniaturizing essential components of spacecraft, the last decade has witnessed an important development of nano- and micro-satellites. Beyond the mere technological experiment, these small satellites are now considered as important complements of much larger and more sophisticated probes to do scientific research. In this context we are conducting a feasibility study of a UV photometer on-board a 3U CubeSat. The scientific purpose of this payload will be to collect time series of photometric measurements of bright massive stars. These massive stars are very hot and luminous objects emitting copious amounts of UV radiation. The properties of these stars during their life and their death in gigantic supernova explosions make them key players for the evolution of the Universe. The UV photometer will be used for imaging photometric observations of massive stars in the spectral range from 250 to 350 nm. The strength of space photometry is the absence of signal perturbation by the Earth’s atmosphere and the continuity of the time-series. Precisely measuring photometric variations allows studying radial and non-radial pulsations of stars. This discipline, called asteroseismology, is currently the most powerful technique for probing the physical conditions in the interiors of stars. An important problem in asteroseismology of massive stars is the mode identification. Simultaneous observations in the near UV (250-350 nm) and in the visible (600 nm) provide the best combination for precise and accurate mode identification based on amplitude ratios in massive stars. Data in the latter pass-band are currently covered by the satellites of the BRITE constellation. Combining the observations of our instrument with those of BRITE will hence result in unprecedented results for pulsating massive stars. The baseline for the UV photometer is a Ritchey-Chrétien telescope composed of two reflective hyperbolic mirrors that focalize the light coming from space onto a focal plane protected by an optical filter. We will present the optimized optical design of the payload and its associated optical sensor. A photometric budget taking into account the characteristics of the target’s stars and the payload performances will also be presented. We will further discuss the observation strategy. Finally, the accommodation of the payload in the spacecraft and its sub-units will be shown as well as mission and preliminary thermal analyses of the whole system obtained after accommodation

Conception of a near-IR spectrometer for ground-based observations of massive stars

In our contribution, we outline the different steps in the design of a fiber-fed spectrographic instrument that intends to observe massive stars. Starting from the derivation of theoretical relationships from the scientific requirements and telescope characteristics, the entire optical design of the spectrograph is presented. Specific optical elements, such as a toroidal lens, are introduced to improve the instrument’s performances. Then, the verification of predicted optical performances is investigated through optical analyses such as resolution checking. Eventually, the star positioning system onto the central fiber core is explained