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1. Measurement of the polarisation in the auroral N2+ 427.8 nm band

Author

Barthelemy Mathieu, Lamy Hervé, Vialatte Anne, Johnsen Magnar Gullikstad, Cessateur Gaël, and Zaourar Naïma

Subjects
polarisation, aurora, space weather-ionosphere-instrumentation, Meteorology. Climatology, QC851-999
Abstract

In this paper, we provide for the first time polarisation measurements of the N+2 N 2 + $ {\mathrm{N}}_2^{+}$ band at 427.8 nm performed with Premier Cru, a dedicated spectropolarimeter to investigate the polarisation of auroral emission lines between 400 and 700 nm. Details about the instrument, the observing conditions and the data analysis procedure are provided. Results obtained during three nights in March 2017 in Skibotn, Norway, indicate that the auroral blue line is polarised with a degree of linear polarisation of a few %. Due to weak Signal-to-Noise Ratios (SNR), these measurements still need to be taken with caution since none of the individual data set has a detection with a 3σ confidence level. However, results integrated over the entire observing period each night do show a 3σ detection but due to the long integration period, the origin of this polarisation cannot be linked to a specific type of aurora (diffuse vs structured arc) or specific ionospheric or geomagnetic conditions. These observations need to be confirmed with an improved design to increase the SNR and decrease the exposure time. When available, these improved measurements of the blue line polarisation will be important to better understand the physics of auroral processes at altitudes below 100 km where the N2+ emission occurs and possibly for space weather applications if the polarisation varies with ionospheric/geomagnetic conditions.

Published
2019
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2. Quo vadis, European Space Weather community?

Author

Lilensten Jean, Dumbović Mateja, Spogli Luca, Belehaki Anna, Van der Linden Ronald, Poedts Stefaan, Barata Teresa, Bisi Mario M., Cessateur Gaël, De Donder Erwin, Guerrero Antonio, Kilpua Emilia, Korsos Marianna B., Pinto Rui F., Temmer Manuela, Tsagouri Ioanna, Urbář Jaroslav, and Zuccarello Francesca

Subjects
space weather, programmatics, europe, Meteorology. Climatology, QC851-999
Abstract

This paper was written by a group of European researchers believing that now is the right time to frame the Space Weather and Space Climate discipline in Europe for future years. It is devoted to openly discussing the organisation and sustainability of the European Space Weather community and its assets in the (near) future. More specifically, we suggest that the European Space Weather community lacks a uniting organisation to help the community to sustain and develop the successful efforts made thus far. Our aim is not to draw a complete and exhaustive panorama of Space Weather throughout the world, nor even throughout Europe. It is not a new white paper on the science and applications: there exist many (e.g. Tsurutani et al., 2020 Nonlinear Processes Geophys 27(1): 75–119); nor another roadmap: several important have been published recently (e.g. Schrijver et al., 2015. Adv Space Res 55(12): 2745–2807; Opgenoorth et al., 2019. J Space Weather Space Clim 9: A37). Our aim is to question our practices and organisation in front of several changes that have occurred in the recent years and to set the ground to provide coordinated answers to these questions being posed in Europe, and to make these answers discussed throughout the world. This group was assembled first through a series of sessions devoted to the sustainability of Space Weather research during the European Space Weather Week (ESWW) series of meetings, specifically: ESWW 14 (2017), ESWW 15 (2018), and ESWW 16 (2019). It then grew from discussions and personal contacts. The authors do not pretend to identify the full range of opinions in Europe, although they do come from 13 different European countries with a large span of ages (around half are below the age of 40 years old at the time of writing) with a good gender balance ending with a diverse mix of young and motivated scientists and senior people who have played a role in shaping the Space Weather community in Europe. The questions and the propositions to organise Space Weather in Europe in the future result from their discussions through these meetings and through remote meetings during the pandemic. We wish to share them with all those who consider themselves as members of the European Space Weather community and/or are interested in its future and to propose actions. We do this, bearing in mind that Europe plays a key international role in Space Weather which extends beyond the ESA and EU/EC geographic area.

Published
2021
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3. Photochemistry-emission coupled model for Europa and Ganymede

Author

Cessateur Gaël, Barthelemy Mathieu, and Peinke Isabel

Subjects
Jovian moons, Aeronomy, Airglow, UV flux, Solar activity, Meteorology. Climatology, QC851-999
Abstract

In the frame of the JUICE mission, preliminary studies of the Jupiter’s icy moons, such as Ganymede and Europa, are mandatory. The present paper aims at characterizing the impact of the solar UV flux and its variability on their atmospheres. The solar UV radiation is responsible for the photoionization, photodissociation, and photoexcitation processes within planetary atmospheres. A 1-D photoabsorption model has been developed for different observational geometries, on the basis of a neutral atmospheric model. Considering various production and loss mechanisms but also the transport of oxygen atoms, we estimate the red and green line emissions from photo impact-induced excitation only. These dayglow emissions can represent few percent of the global airglow emission, mainly dominated by electron-induced excitation in auroral regions. For limb viewing conditions, red line emission is bright enough to be detected from actual spectrometers, from 338 R to 408 R according to the solar activity. This is also the case for the green line with 8 R at limb viewing. Considering a different neutral atmosphere model, with an O2 column density 50% more important, leads to a 14% increase in the red line emissions for limb viewing close to the surface. This difference could be important enough to infer which neutral model is the most likely. However, uncertainties on the solar UV flux might also prevent to constrain the O2 column density when using ground-based observations in the visible only. The impact of solar flares on the red line emissions for Europa has also been investigated within a planetary space weather context.

Published
2016
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4. Sensitivity of upper atmospheric emissions calculations to solar/stellar UV flux

Author

Barthelemy Mathieu and Cessateur Gaël

Subjects
space weather, solar spectrum (UV), aeronomy, airglow, Meteorology. Climatology, QC851-999
Abstract

The solar UV (UltraViolet) flux, especially the EUV (Extreme UltraViolet) and FUV (Far UltraViolet) components, is one of the main energetic inputs for planetary upper atmospheres. It drives various processes such as ionization, or dissociation which give rise to upper atmospheric emissions, especially in the UV and visible. These emissions are one of the main ways to investigate the upper atmospheres of planets. However, the uncertainties in the flux measurement or modeling can lead to biased estimates of fundamental atmospheric parameters, such as concentrations or temperatures in the atmospheres. We explore the various problems that can be identified regarding the uncertainties in solar/stellar UV flux by considering three examples. The worst case appears when the solar reflection component is dominant in the recorded spectrum as is seen for outer solar system measurements from HST (Hubble Space Telescope). We also show that the estimation of some particular line parameters (intensity and shape), especially Lyman α, is crucial, and that both total intensity and line profile are useful. In the case of exoplanets, the problem is quite critical since the UV flux of their parent stars is often very poorly known.

Published
2014
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5. New observation strategies for the solar UV spectral irradiance

Author

Kretzschmar Matthieu, BenMoussa Ali, Dudok de Wit Thierry, Lilensten Jean, and Cessateur Gaël

Subjects
Space Weather, Solar Spectrum (UV), Modelling, Instrumentation, Meteorology. Climatology, QC851-999
Abstract

Many applications in space weather and in space situational awareness require continuous solar spectral irradiance measurements in the UV, and to a lesser degree in the visible band. Most space-borne solar radiometers are made out of two different parts: (i) a front filter that selects the passband and (ii) a detector that is usually based on silicon technology. Both are prone to degradation, which may be caused either by the degradation of the filter coating due to local deposition or to structural changes, or by the degradation of the silicon detector by solar radiative and energetic particle fluxes. In this study, we provide a theoretical analysis of the filter degradation that is caused by structural changes such as pinholes; contamination-induced degradation will not be considered. We then propose a new instrumental concept, which is expected to overcome, at least partially, these problems. We show how most of the solar UV spectrum can be reconstructed from the measurement of only five spectral bands. This instrumental concept outperforms present spectrometers in terms of degradation. This new concept in addition overcomes the need for silicon-based detectors, which are replaced by wide band gap material detectors. Front filters, which can contribute to in-flight degradation, therefore are not required, except for the extreme-UV (EUV) range. With a small weight and a low telemetry, this concept may also have applications in solar physics, in astrophysics and in planetology.

Published
2012
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6. Extreme ultraviolet solar irradiance during the rising phase of solar cycle 24 observed by PROBA2/LYRA

Author

Zender Joe, Dominique Marie, Dammasch Ingolf E., Kretzschmar Matthieu, Cessateur Gaël, and D’Huys Elke

Subjects
irradiance, solar cycle, spectral irradiance, data analysis, Meteorology. Climatology, QC851-999
Abstract

The Large-Yield Radiometer (LYRA) is a radiometer that has monitored the solar irradiance at high cadence and in four pass bands since January 2010. Both the instrument and its spacecraft, PROBA2 (Project for OnBoard Autonomy), have several innovative features for space instrumentation, which makes the data reduction necessary to retrieve the long-term variations of solar irradiance more complex than for a fully optimized solar physics mission. In this paper, we describe how we compute the long-term time series of the two extreme ultraviolet irradiance channels of LYRA and compare the results with those of SDO/EVE. We find that the solar EUV irradiance has increased by a factor of 2 since the last solar minimum (between solar cycles 23 and 24), which agrees reasonably well with the EVE observations.

Published
2012
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7. Atmospheric Escape Processes and Planetary Atmospheric Evolution

Author

Gronoff, Guillaume, Arras, Phil, Baraka, Suleiman M, Bell, Jared M, Cessateur, Gaël, Cohen, Ofer, Curry, Shannon M., Drake, Jeremy J, Elrod, Meredith K, Erwin, Justin T., Garcia-Sage, Katherine, Garraffo, Cecilia, Glocer, Alex, Heavens, Nicholas Gray, Lovato, Kylie, Maggiolo, Romain, Parkinson, Christopher D., Wedlund, Cyril L. Simon, Weimer, Daniel R, and Moore, William B.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics, Physics - Space Physics
Abstract

The habitability of the surface of any planet is determined by a complex evolution of its interior, surface, and atmosphere. The electromagnetic and particle radiation of stars drive thermal, chemical and physical alteration of planetary atmospheres, including escape. Many known extrasolar planets experience vastly different stellar environments than those in our Solar system: it is crucial to understand the broad range of processes that lead to atmospheric escape and evolution under a wide range of conditions if we are to assess the habitability of worlds around other stars. One problem encountered between the planetary and the astrophysics communities is a lack of common language for describing escape processes. Each community has customary approximations that may be questioned by the other, such as the hypothesis of H-dominated thermosphere for astrophysicists, or the Sun-like nature of the stars for planetary scientists. Since exoplanets are becoming one of the main targets for the detection of life, a common set of definitions and hypotheses are required. We review the different escape mechanisms proposed for the evolution of planetary and exoplanetary atmospheres. We propose a common definition for the different escape mechanisms, and we show the important parameters to take into account when evaluating the escape at a planet in time. We show that the paradigm of the magnetic field as an atmospheric shield should be changed and that recent work on the history of Xenon in Earth's atmosphere gives an elegant explanation to its enrichment in heavier isotopes: the so-called Xenon paradox.

Published
2020
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8. Unexpected increase of the deuterium to hydrogen ratio in the Venus mesosphere.

Author

Mahieux, Arnaud, Viscardy, Sébastien, Yelle, Roger Vincent, Hiroki Karyu, Chamberlain, Sarah, Robert, Séverine, Piccialli, Arianna, Trompet, Loïc, Erwin, Justin Tyler, Ubukata, Soma, Hiromu Nakagawa, Shungo Koyama, Maggiolo, Romain, Pereira, Nuno, Cessateur, Gaël, Willame, Yannick, and Vandaele, Ann Carine

Subjects
PHASE transitions, HYDROLOGIC cycle, ISOTOPIC fractionation, MESOSPHERE, WATER vapor
Abstract

This study analyzes H2O and HDO vertical profiles in the Venus mesosphere using Venus Express/Solar Occultation in the InfraRed data. The findings show increasing H2O and HDO volume mixing ratios with altitude, with the D/H ratio rising significantly from 0.025 at ~70 km to 0.24 at ~108 km. This indicates an increase from 162 to 1,519 times the Earth's ratio within 40 km. The study explores two hypotheses for these results: isotopic fractionation from photolysis of H2O over HDO or from phase change processes. The latter, involving condensation and evaporation of sulfuric acid aerosols, as suggested by previous authors [X. Zhang et al., Nat. Geosci. 3, 834-837 (2010)], aligns more closely with the rapid changes observed. Vertical transport computations for H2O, HDO, and aerosols show water vapor downwelling and aerosols upwelling. We propose a mechanism where aerosols form in the lower mesosphere due to temperatures below the water condensation threshold, leading to deuterium-enriched aerosols. These aerosols ascend, evaporate at higher temperatures, and release more HDO than H2O, which are then transported downward. Moreover, this cycle may explain the SO2 increase in the upper mesosphere observed above 80 km. The study highlights two crucial implications. First, altitude variation is critical to determining the Venus deuterium and hydrogen reservoirs. Second, the altitude-dependent increase of the D/H ratio affects H and D escape rates. The photolysis of H2O and HDO at higher altitudes releases more D, influencing long-term D/H evolution. These findings suggest that evolutionary models should incorporate altitude-dependent processes for accurate D/H fractionation predictions. [ABSTRACT FROM AUTHOR]

Published
2024
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9. The effect of the Earth’s magnetosphere on the solar wind energy dissipation in the ionosphere: Evolution over geological time scales

Author

Maggiolo, Romain, Maes, Lukas, Alonso Tagle, Maria Luisa, Cessateur, Gaël, Darrouzet, Fabien, De Keyser, Johan, and Gunell, Herbert

Abstract

The Sun is the dominant energy source for ionizing atmospheric material and energizing a fraction of it to energies above the gravitational binding energy. Maggiolo et al. (2022) recently showed that, for current conditions, the solar wind energy dissipated in the Earth’s upper atmosphere is higher than it would be if the Earth were not magnetized. Indeed, despite shielding the atmosphere from the solar wind, the Earth’s magnetosphere has a much larger cross section with the solar wind than the planet itself. It thus dramatically increases the size of the interaction region between the solar wind and the planetary environment and thus the amount of solar wind energy that can potentially be diverted toward the upper atmosphere.In this study, we investigate the effect of the Earth’s magnetosphere on the solar wind energy dissipation in the atmosphere during the last 4 billion years, when the Sun was more active. The solar wind density and velocity were higher in the past which has two opposite effects. On the one hand, the Earth’s magnetosphere was more compressed by the higher solar wind pressure, reducing its cross section with the solar wind. On the other hand the solar wind energy flux density was higher. We use physical considerations and extrapolate current measurements to constrain the role of the Earth’s magnetosphere on the energy coupling between the solar wind and the upper atmosphere for such conditions., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Published
2023

10. PLIP: An imaging Polarimeter for the Auroral line Emissions

Author

Cessateur, Gaël, primary, Lamy, Herve, additional, Bosse, Léo, additional, Barthelemy, Mathieu, additional, Lilensten, Jean, additional, Johnsen, Magnar G., additional, Auriol, Frederique, additional, Catalfamo, Maxime, additional, and Pujol, Olivier, additional

Published
2023
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11. First evidence of polarized emissions in pulsating aurorae

Author

Bosse, Leo, primary, Cessateur, Gaël, additional, Lamy, Hervé, additional, Lilensten, Jean, additional, Gillet, Nicolas, additional, Brogniez, Colette, additional, Pujol, Olivier, additional, Rochat, Sylvain, additional, Curaba, Stéphane, additional, Delboulbé, Alain, additional, and Johnsen, Magnar G., additional

Published
2023
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14. Modelling Atmospheric Erosion for Terrestrial Planets in the Solar System

Author

Alonso Tagle, Maria Luisa, Maggiolo, Romain, Gunell, Herbert, De Keyser, Johan, Cessateur, Gaël, Lapenta, Giovanni, Pierrard, Viviane, and Vandaele, Ann Carine

Abstract

Since the Great Oxidation Event, the oxygen escape rate on Earth has changed over time mainly due to solar evolution. Two solar agents drive the Earth’s atmospheric erosion rate: the solar wind and the EUV radiation. The first one affects the non-thermal processes by changing the plasma conditions, and the second one affects both types of processes: by increasing the atmospheric temperature, and by modifying the ion production rate. Hence EUV radiation affects atmospheric parameters, such as the exobase distance and neutral density, which influence the escape rate. In this work, we describe a model that uses in-situ measurements and physical considerations to estimate the effect of solar evolution on the atmospheric loss rate. Physical assumptions are made to describe the contribution of the solar wind pressure on each erosion mechanism. The main objective is to reproduce earlier solar conditions to constrain oxygen loss over geological time scales. Seven different mechanisms are studied, to determine the fundamental factors that have a significant impact on the oxygen escape rate in the past Earth. We discuss the effects of the exospheric parameters and solar wind drivers on the oxygen erosion rate. We examine their relevance for total oxygen loss and their influence on the stability of our atmosphere.

Published
2023
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15. First evidence of polarized emissions in pulsating aurorae

Author

Bosse, Léo, Cessateur, Gaël, Hervé, Lamy, Lilensten, Jean, Gillet, Nicolas, Brogniez, Colette, and Pujol, Olivier

Abstract

In the last decade, several instruments have been developped to measure the auroral light polarisation. However, its study has faced the issue of anthropic light pollution and scattering in the lower atmosphere (Bosse et al., 2020). To overcome this challenge the most succesfull method was the use of a polarised radiative transfer model to identify the light pollution contribution (Bosse et al., 2022). This year, a new look at the data revealed that pulsating aurorae are polarised, and that this polarisation carries a lot of information. Searching for polarisation in pulsating aurorae allows us to dismiss any external source of polarisation that is not synched with the pulsation of the aurora. Thus light pollution is not a problem anymore.These polarisation patterns are seen in the green atomic oxygen line at 557.7 nm, the 1st N2+ negative band at 391.4 nm (purple) and 427.8 nm (blue).Today, there are no clear explanations on the origin of this auroral polarisation, or its relation to the local state of the upper atmosphere. An hypothesis is that this polarisation can be either created directly at the radiative de-excitation or may occur when the non-polarised emission crosses the ionospheric currents.We will present how these new findings confirm the ionospheric origin of the polarisation observed from the ground, and discussing about the opportunities these observations and models offer in the frame of space weather, aerosol and light pollution study., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Published
2023

16. The Space Weather and Ultraviolet Solar Variability (SWUSV) Microsatellite Mission

Author

Meftah, Mustapha, Hauchecorne, Alain, Keckhut, Philippe, Sarkissian, Alain, Marchand, Marion, Irbah, Abdenour, Quémerais, Éric, Bekki, Slimane, Foujols, Thomas, Kretzschmar, Matthieu, Cessateur, Gaël, Shapiro, Alexander, Schmutz, Werner, Kuzin, Sergey, Slemzin, Vladimir, Urnov, Alexander, Bogachev, Sergey, Merayo, José, Brauer, Peter, Tsinganos, Kanaris, Paschalis, Antonis, Mahrous, Ayman, Khaled, Safinaz, Ghitas, Ahmed, Marzouk, Besheir, Zaki, Amal, Hady, Ahmed A., Kariyappa, Rangaiah, and Damé, Luc

Published
2013
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22. The Effect of Cosmic Rays on Cometary Nuclei. I. Dose Deposition

Author

Gronoff, Guillaume, Maggiolo, Romain, Cessateur, Gaël, Moore, W. B., Airapetian, Vladimir, De Keyser, Johan, Dhooghe, Frederick, Gibbons, Andrew, Gunell, Herbert, Mertens, C. J., Rubin, Martin, Hosseini, S., Gronoff, Guillaume, Maggiolo, Romain, Cessateur, Gaël, Moore, W. B., Airapetian, Vladimir, De Keyser, Johan, Dhooghe, Frederick, Gibbons, Andrew, Gunell, Herbert, Mertens, C. J., Rubin, Martin, and Hosseini, S.

Abstract

Comets are small bodies thought to contain the most pristine material in the solar system. However, since their formation ≈4.5 Gy ago, they have been altered by different processes. While not exposed to much electromagnetic radiation, they experience intense particle radiation. Galactic cosmic rays and solar energetic particles have a broad spectrum of energies and interact with the cometary surface and subsurface; they are the main source of space weathering for a comet in the Kuiper Belt or in the Oort Cloud, and also affect the ice prior to the comet agglomeration. While low-energy particles interact only with the cometary surface, the most energetic ones deposit a significant amount of energy down to tens of meters. This interaction can modify the isotopic ratios in cometary ices and create secondary compounds through radiolysis, such as O2 and H2O2 (Paper II). In this paper, we model the energy deposition of energetic particles as a function of depth using a Geant4 application modified to account for the isotope creation process. We quantify the energy deposited in cometary nucleus by galactic cosmic rays and solar energetic particles. The consequences of the energy deposition on the isotopic and chemical composition of cometary ices and their implication on the interpretation of cometary observations, notably of 67P/Churyumov Gerasimenko by the ESA Rosetta spacecraft, will be discussed in Paper II.

Published
2020
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23. The Effect of Cosmic Rays on Cometary Nuclei. II. Impact on Ice Composition and Structure

Author

Maggiolo, Romain, Gronoff, Guillaume, Cessateur, Gaël, Moore, William W.B., Airapetian, Vladimir, De Keyser, Johan, Dhooghe, Frederik, Gibbons, Andrew, Gunell, Herbert, Mertens, Christopher C.J., Rubin, Martin, Hosseini, Sona, Maggiolo, Romain, Gronoff, Guillaume, Cessateur, Gaël, Moore, William W.B., Airapetian, Vladimir, De Keyser, Johan, Dhooghe, Frederik, Gibbons, Andrew, Gunell, Herbert, Mertens, Christopher C.J., Rubin, Martin, and Hosseini, Sona

Abstract

Since their formation in the protosolar nebula some ∼4.5 billion years ago, comets are in storage in cold distant regions of the solar system, the Kuiper Belt/scattered disk or Oort Cloud. Therefore, they have been considered as mostly unaltered samples of the protosolar nebula. However, a significant dose of energy is deposited by galactic cosmic rays (GCRs) into the outermost tens of meters of cometary nuclei during their stay in the Oort Cloud or Kuiper Belt. We investigate the impact of energy deposition by GCRs on cometary nuclei. We use experimental results from laboratory experiments and the energy deposition by GCRs estimated by Gronoff et al. (2020), to discuss the depth down to which the cometary nucleus is altered by GCRs. We show that GCRs do not significantly change the isotopic composition of cometary material but modify the chemical composition and the ice structure in the outer layers of the nucleus, which cannot be considered as pristine solar nebula material. We discuss the effect of the collisional history of comets on the distribution of processed material inside the nucleus and its implication on the observation of comets., SCOPUS: ar.j, DecretOANoAutActif, info:eu-repo/semantics/published

Published
2020

25. Atmospheric Escape Processes and Planetary Atmospheric Evolution

Author

Gronoff, Guillaume, primary, Arras, Phil, additional, Baraka, Suleiman M, additional, Bell, Jared M, additional, Cessateur, Gaël, additional, Cohen, Ofer, additional, Curry, Shannon M., additional, Drake, Jeremy J, additional, Elrod, Meredith K, additional, Erwin, Justin T., additional, Garcia-Sage, Katherine, additional, garraffo, Cecilia, additional, Glocer, Alex, additional, Heavens, Nicholas Gray, additional, Lovato, Kylie, additional, Maggiolo, Romain, additional, Parkinson, Christopher D., additional, Simon Wedlund, Cyril L., additional, Weimer, Daniel R, additional, and Moore, William B., additional

Published
2020
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26. Effect of the Surface Roughness of Icy Grains on Molecular Oxygen Chemistry in Molecular Clouds

Author

Maggiolo, Romain, Gibbons, Andrew, Cessateur, Gaël, Keyser, De J.D., Dhooghe, Frederik, Gunell, Herbert, Loreau, Jérôme, Mousis, Olivier, Vaeck, Nathalie, Maggiolo, Romain, Gibbons, Andrew, Cessateur, Gaël, Keyser, De J.D., Dhooghe, Frederik, Gunell, Herbert, Loreau, Jérôme, Mousis, Olivier, and Vaeck, Nathalie

Abstract

Molecular cloud and protosolar nebula chemistry involves a strong interaction between the gas phase and the surface of icy grains. The exchanges between the gas phase and the solid phase depend not only on the adsorption and desorption rates but also on the geometry of the surface of the grains. Indeed, for sufficient levels of surface roughness, atoms and molecules have a significant probability to collide with the grain icy mantle several times before being potentially captured. In consequence, their net sticking probability may differ from their sticking probability for a single collision with the grain surface. We estimate the effectiveness of the recapture on uneven surfaces for the various desorption processes at play in astrophysical environments. We show that surface roughness has a significant effect on the desorption rates. We focus in particular on the production of O2 since unexpectedly large amounts of it, probably incorporated in the comet when it formed, have been detected in the coma of comet 67P by the Rosetta probe. Our results suggest that the higher escape probability of hydrogen compared to heavier species on rough surfaces can contribute to enhancing the production of O2 in the icy mantles of grains while keeping its abundance low in the gas phase and may significantly decrease the desorption probability of molecules involved in the O2 chemical network., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2019

28. O2 interaction with water ice surfaces for desorption modelling in astrochemical applications

Author

Quantum Chemistry in Belgium 13, Gibbons, Andrew, Loreau, Jérôme, Cessateur, Gaël, Dhooghe, Frederik, Gunell, H., Maggiolo, Romain, De Keyser, Johan, Vaeck, Nathalie, Quantum Chemistry in Belgium 13, Gibbons, Andrew, Loreau, Jérôme, Cessateur, Gaël, Dhooghe, Frederik, Gunell, H., Maggiolo, Romain, De Keyser, Johan, and Vaeck, Nathalie

Abstract

info:eu-repo/semantics/nonPublished

Published
2018

29. A new solar reference spectrum from 165 to 3088 nm

Author

Damé, Luc, Meftah, Mustapha, Bolsée, David, Pereira, Nuno, Bekki, Slimane, Hauchecorne, Alain, Irbah, Abdanour, Cessateur, Gaël, Sluse, Dominique, Cardon, Catherine, HELIOS - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), STRATO - LATMOS, and Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB)

Subjects
[SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.SR] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR]
Abstract

International audience; Since April 5, 2008 and until February 15, 2017 the SOLAR/SOLSPEC spectro-radiometer on the International Space Station performed accurate measurements of Solar Spectral Irradiance (SSI) from the far ultraviolet to the infrared (165 nm to 3088 nm). These measurements are of primary importance for a better understanding of solar physics and of the impact of solar variability on climate (via Earth's atmospheric photochemistry). In particular, a new reference solar spectrum is established covering most of the unusual solar cycle 24 from minimum in 2008 to maximum. Temporal variability in the UV (165 to 400 nm) is presented in several wavelengths bands. These results are possible thanks to revised engineering corrections, improved calibrations and new procedures to account for thermal and aging advanced corrections. Uncertainties on these measurements are evaluated and compare favorably with other instruments.

Published
2017

31. 3D model of auroral emissions for Europa

Author

2017 AGU Fall Meeting (2017-12: New Orleans, USA), Cessateur, Gaël, Barthelemy, M., Rubin, M., Lilenstein, J., Maggiolo, Romain, De Keyser, Johan, Gunell, H., Loreau, Jérôme, 2017 AGU Fall Meeting (2017-12: New Orleans, USA), Cessateur, Gaël, Barthelemy, M., Rubin, M., Lilenstein, J., Maggiolo, Romain, De Keyser, Johan, Gunell, H., and Loreau, Jérôme

Abstract

info:eu-repo/semantics/nonPublished

Published
2017

32. Evidence for distributed gas sources of hydrogen halides in the coma of comet 67P/Churyumov-Gerasimenko

Author

De Keyser, Johan, Dhooghe, Frederik, Altwegg, Kathrin, Balsiger, Hans, Berthelier, Jean Jacques, Briois, Christelle, Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., Equeter, Eddy, Fiethe, Björn, Fuselier, S. A., Gasc, Sebastian S G, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Tzou, Chiayu C.Y., Wurz, Peter, De Keyser, Johan, Dhooghe, Frederik, Altwegg, Kathrin, Balsiger, Hans, Berthelier, Jean Jacques, Briois, Christelle, Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., Equeter, Eddy, Fiethe, Björn, Fuselier, S. A., Gasc, Sebastian S G, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Tzou, Chiayu C.Y., and Wurz, Peter

Abstract

info:eu-repo/semantics/published

Published
2017

33. Halogens as tracers of protosolar nebula material in comet 67P/Churyumov-Gerasimenko

Author

Dhooghe, Frederik, De Keyser, Johan, Altwegg, Kathrin, Briois, Christelle, Balsiger, Hans, Berthelier, J.-J., Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., Equeter, Eddy, Fiethe, Björn, Fray, Nicolas, Fuselier, Stephen Anthony, Gasc, Sebastian S G, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Hilchenbach, Martin, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Tzou, Chiayu C.Y., Wurz, Peter, Dhooghe, Frederik, De Keyser, Johan, Altwegg, Kathrin, Briois, Christelle, Balsiger, Hans, Berthelier, J.-J., Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., Equeter, Eddy, Fiethe, Björn, Fray, Nicolas, Fuselier, Stephen Anthony, Gasc, Sebastian S G, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Hilchenbach, Martin, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Tzou, Chiayu C.Y., and Wurz, Peter

Abstract

We report the first in situ detection of halogens in a cometary coma, that of 67P/Churyumov- Gerasimenko. Neutral gas mass spectra collected by the European Space Agency's Rosetta spacecraft during four periods of interest from the first comet encounter up to perihelion indicate that the main halogen-bearing compounds are HF, HCl and HBr. The bulk elemental abundances relative to oxygen are~8.9×10-5 for F/O,~1.2×10-4 forCl/O and~2.5×10-6 for Br/O, for the volatile fraction of the comet. The cometary isotopic ratios for 37Cl/35Cl and 81Br/79Br match the Solar system values within the error margins. The observations point to an origin of the hydrogen halides in molecular cloud chemistry, with frozen hydrogen halides on dust grains, and a subsequent incorporation into comets as the cloud condensed and the Solar system formed., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2017

34. 2D forbidden oxygen line emission maps for various comets

Author

EGU (23-28/04/2017: Vienna), Cessateur, Gaël, De Keyser, Johan, Maggiolo, Romain, Rubin, Martin, Gronoff, Guillaume, Gibbons, Andrew, Jehin, Emmanuel, Dhooghe, Frederik, Gunell, H., Vaeck, Nathalie, Loreau, Jérôme, EGU (23-28/04/2017: Vienna), Cessateur, Gaël, De Keyser, Johan, Maggiolo, Romain, Rubin, Martin, Gronoff, Guillaume, Gibbons, Andrew, Jehin, Emmanuel, Dhooghe, Frederik, Gunell, H., Vaeck, Nathalie, and Loreau, Jérôme

Abstract

info:eu-repo/semantics/nonPublished

Published
2017

35. Plasma waves at Comet 67P/Churyumov-Gerasimenko: in the diamagnetic cavity and outside it

Author

EGU 2017 (23-28/04/2017: Vienna), Gunell, H., Altwegg, Kathrin, Cessateur, Gaël, De Keyser, Johan, Dhooghe, Frederik, Eriksson, Anders, Gibbons, Andrew, Glassmeier, Karl Heinz, Götz, Charlotte C G, Karlsson, T., Hamrin, Maria, Henri, Pierre, Maggiolo, Romain, Nilsson, Hans, Odelstad, Elias, Rubin, Martin, Simon Wedlund, Cyril, Stenberg Wieser, Gabriella, Tzou, Chiayu C.Y., Vallieres, Xavier, EGU 2017 (23-28/04/2017: Vienna), Gunell, H., Altwegg, Kathrin, Cessateur, Gaël, De Keyser, Johan, Dhooghe, Frederik, Eriksson, Anders, Gibbons, Andrew, Glassmeier, Karl Heinz, Götz, Charlotte C G, Karlsson, T., Hamrin, Maria, Henri, Pierre, Maggiolo, Romain, Nilsson, Hans, Odelstad, Elias, Rubin, Martin, Simon Wedlund, Cyril, Stenberg Wieser, Gabriella, Tzou, Chiayu C.Y., and Vallieres, Xavier

Abstract

info:eu-repo/semantics/nonPublished

Published
2017

36. Distributed sources of hydrogen halides in the coma of comet 67P/Churyumov-Gerasimenko

Author

Comet formation paradigm after Rosetta (Comets Workshop 2017: 19-23/06/2017: Sofia), De Keyser, Johan, Dhooghe, Frederik, Altwegg, Kathrin, Balsiger, Hans, Berthelier, Jean Jacques, Briois, Christelle, Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., Equeter, Eddy, Fiethe, Björn, Fuselier, S. A., Gasc, Sebastian S G, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Tzou, Chiayu C.Y., Wurz, Peter, Comet formation paradigm after Rosetta (Comets Workshop 2017: 19-23/06/2017: Sofia), De Keyser, Johan, Dhooghe, Frederik, Altwegg, Kathrin, Balsiger, Hans, Berthelier, Jean Jacques, Briois, Christelle, Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., Equeter, Eddy, Fiethe, Björn, Fuselier, S. A., Gasc, Sebastian S G, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Tzou, Chiayu C.Y., and Wurz, Peter

Abstract

info:eu-repo/semantics/nonPublished

Published
2017

37. Ion acoustic waves at comet 67P/Churyumov-Gerasimenko: Observations and computations

Author

Gunell, H., Nilsson, Hans, Hamrin, Maria, Eriksson, Anders, Odelstad, Elias, Maggiolo, Romain, Henri, Pierre, Vallieres, Xavier, Altwegg, Kathrin, Tzou, Chiayu C.Y., Rubin, Martin, Glassmeier, Karl Heinz, Wieser, Gabriella Stenberg, Simon Wedlund, Cyril, De Keyser, Johan, Dhooghe, Frederik, Cessateur, Gaël, Gibbons, Andrew, Gunell, H., Nilsson, Hans, Hamrin, Maria, Eriksson, Anders, Odelstad, Elias, Maggiolo, Romain, Henri, Pierre, Vallieres, Xavier, Altwegg, Kathrin, Tzou, Chiayu C.Y., Rubin, Martin, Glassmeier, Karl Heinz, Wieser, Gabriella Stenberg, Simon Wedlund, Cyril, De Keyser, Johan, Dhooghe, Frederik, Cessateur, Gaël, and Gibbons, Andrew

Abstract

Context. On 20 January 2015 the Rosetta spacecraft was at a heliocentric distance of 2.5 AU, accompanying comet 67P/Churyumov-Gerasimenko on its journey toward the Sun. The Ion Composition Analyser (RPC-ICA), other instruments of the Rosetta Plasma Consortium, and the ROSINA instrument made observations relevant to the generation of plasma waves in the cometary environment. Aims. Observations of plasma waves by the Rosetta Plasma Consortium Langmuir probe (RPC-LAP) can be explained by dispersion relations calculated based on measurements of ions by the Rosetta Plasma Consortium Ion Composition Analyser (RPC-ICA), and this gives insight into the relationship between plasma phenomena and the neutral coma, which is observed by the Comet Pressure Sensor of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis instrument (ROSINA-COPS). Methods. We use the simple pole expansion technique to compute dispersion relations for waves on ion timescales based on the observed ion distribution functions. These dispersion relations are then compared to the waves that are observed. Data from the instruments RPC-LAP, RPC-ICA and the mutual impedance probe (RPC-MIP) are compared to find the best estimate of the plasma density. Results. We find that ion acoustic waves are present in the plasma at comet 67P/Churyumov-Gerasimenko, where the major ion species is H2O+. The bulk of the ion distribution is cold, kBTi = 0.01 eV when the ion acoustic waves are observed. At times when the neutral density is high, ions are heated through acceleration by the solar wind electric field and scattered in collisions with the neutrals. This process heats the ions to about 1 eV, which leads to significant damping of the ion acoustic waves. Conclusions. In conclusion, we show that ion acoustic waves appear in the H2O+ plasmas at comet 67P/Churyumov-Gerasimenko and how the interaction between the neutral and ion populations affects the wave properties., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2017

38. Distributed sources for the hydrogen halides in the coma of comet 67P/Churyumov- Gerasimenko

Author

European Planetary Science Congress (17-22/09/2017: Riga), De Keyser, Johan, Dhooghe, Frederik, Altwegg, Kathrin, Balsiger, Hans, Berthelier, J.-J., Briois, Christelle, Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., Equeter, Eddy, Fiethe, Björn, Fuselier, S. A., Gasc, Sebastian S G, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Tzou, Chiayu C.Y., Wurz, Peter, European Planetary Science Congress (17-22/09/2017: Riga), De Keyser, Johan, Dhooghe, Frederik, Altwegg, Kathrin, Balsiger, Hans, Berthelier, J.-J., Briois, Christelle, Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., Equeter, Eddy, Fiethe, Björn, Fuselier, S. A., Gasc, Sebastian S G, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Tzou, Chiayu C.Y., and Wurz, Peter

Abstract

info:eu-repo/semantics/nonPublished

Published
2017

39. Hydrogen halides at Comet 67P/Churyumov-Gerasimenko as detected by ROSINA/DFMS

Author

EGU 2017 (23-28/04/2017: Vienna), Dhooghe, Frederik, Altwegg, Kathrin, Balsiger, Hans, Berthelier, J.-J., Briois, Christelle, Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., Equeter, Eddy, Fiethe, Björn, Fuselier, S. A., Gasc, Sebastian S G, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Tzou, Chiayu C.Y., Wurz, Peter, EGU 2017 (23-28/04/2017: Vienna), Dhooghe, Frederik, Altwegg, Kathrin, Balsiger, Hans, Berthelier, J.-J., Briois, Christelle, Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., Equeter, Eddy, Fiethe, Björn, Fuselier, S. A., Gasc, Sebastian S G, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Tzou, Chiayu C.Y., and Wurz, Peter

Abstract

info:eu-repo/semantics/nonPublished

Published
2017

40. Effect of non-planarity on the desorption process at the surface of icy grains ;consequences on O2 formation

Author

EGU (23-28/04/2017: Vienna), Maggiolo, Romain, Cessateur, Gaël, Bonnal, Enzo, De Keyser, Johan, Dhooghe, Frederik, Gibbons, Andrew, Mousis, Olivier, Vaeck, Nathalie, Loreau, Jérôme, EGU (23-28/04/2017: Vienna), Maggiolo, Romain, Cessateur, Gaël, Bonnal, Enzo, De Keyser, Johan, Dhooghe, Frederik, Gibbons, Andrew, Mousis, Olivier, Vaeck, Nathalie, and Loreau, Jérôme

Abstract

info:eu-repo/semantics/nonPublished

Published
2017

41. Plasma waves confined to the diamagnetic cavity of comet 67P/Churyumov-Gerasimenko

Author

Gunell, H., Götz, Charlotte C G, Eriksson, Anders, Nilsson, Hans, Simon Wedlund, Cyril, Henri, P, Maggiolo, Romain, Hamrin, Maria, De Keyser, Johan, Rubin, Martin, Stenberg Wieser, Gabriella, Cessateur, Gaël, Dhooghe, Frederik, Gibbons, Andrew, Gunell, H., Götz, Charlotte C G, Eriksson, Anders, Nilsson, Hans, Simon Wedlund, Cyril, Henri, P, Maggiolo, Romain, Hamrin, Maria, De Keyser, Johan, Rubin, Martin, Stenberg Wieser, Gabriella, Cessateur, Gaël, Dhooghe, Frederik, and Gibbons, Andrew

Abstract

info:eu-repo/semantics/published

Published
2017

42. O2 interaction with water ice surfaces for desorption modelling in astrochemical applications

Author

New avenues in molecular theories :From the lab to beyond the Earth (31/08 - 06/09/2017: Belgrade), Gibbons, Andrew, Loreau, Jérôme, Cessateur, Gaël, Dhooghe, Frederik, Gunell, H., Maggiolo, Romain, De Keyser, Johan, Vaeck, Nathalie, New avenues in molecular theories :From the lab to beyond the Earth (31/08 - 06/09/2017: Belgrade), Gibbons, Andrew, Loreau, Jérôme, Cessateur, Gaël, Dhooghe, Frederik, Gunell, H., Maggiolo, Romain, De Keyser, Johan, and Vaeck, Nathalie

Abstract

info:eu-repo/semantics/nonPublished

Published
2017

43. O2 interaction with water ice surfaces for desorption modelling in astrochemical applications

Author

Astrochemical Conference KIDA2017, Gibbons, Andrew, Loreau, Jérôme, Cessateur, Gaël, Dhooghe, Frederik, Gunell, H., Maggiolo, Romain, De Keyser, Johan, Vaeck, Nathalie, Astrochemical Conference KIDA2017, Gibbons, Andrew, Loreau, Jérôme, Cessateur, Gaël, Dhooghe, Frederik, Gunell, H., Maggiolo, Romain, De Keyser, Johan, and Vaeck, Nathalie

Abstract

info:eu-repo/semantics/nonPublished

Published
2017

44. A thermal model of Rosetta/ROSINA/DFMS to assess the effects of solar illumination and thermal inertia of the mass spectrometer on mass spectra at 67P/Churyumov-Gerasimenko

Author

de Keyser, Johan, Gibbons, Andrew, Neefs, Eddy, Equeter, Eddy, Dhooghe, Frederik, Maggiolo, Romain, Cessateur, Gaël, Gunell, Herbert, Altwegg, Kathrin, Berthelier, Jean-Jacques, Briois, Christelle, Calmonte, Ursina, Combi, Michael R., Fiethe, Björn, Fuselier, Stephen, Gombosi, Tamas, Hässig, Myrttha, Le Roy, Léna, Rubin, Martin, Sémon, Thierry, Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Department of Atmospheric, Oceanic, and Space Sciences [Ann Arbor] (AOSS), University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Institute of Computer and Network Engineering [Braunschweig] (IDA), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], and Southwest Research Institute [San Antonio] (SwRI)

Subjects
[SDU]Sciences of the Universe [physics], Astrophysics::Earth and Planetary Astrophysics
Abstract

International audience; The coma composition of comet 67P/Churyumov-Gerasimenko is being analysed in detail with the high mass resolution Double Focussing Mass Spectrometer (DFMS) that is part of the ROSINA instrument suite on board of the Rosetta spacecraft. The Rosetta spacecraft - and DFMS in particular - experiences changing behaviour as the temperature varies with illumination and distance from the Sun. This contribution highlights these changes and their practical consequences for the interpretation of the DFMS mass spectra. A thermal model is presented that addresses thermal behaviour on a long time scale, related to instrument illumination and thermal gradients inside DFMS, and on a short time scale, related to transients after on/off cycling of the instrument and thermal inertia. Both issues adversely affect the problem of establishing a proper instrument mass calibration.

Published
2016

45. 8 years of Solar Spectral Irradiance Observations from the ISS with the SOLAR/SOLSPEC Instrument

Author

Damé, Luc, Boisée, David, Meftah, Mustapha, Irbah, Abdanour, Hauchecorne, Alain, Bekki, Slimane, Pereira, Nuno, Cessateur, Gaël, Marchand, Marion, Thiéblemont, Rémi, Foujols, Thomas, Cardon, Catherine, HELIOS - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), STRATO - LATMOS, and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.ASTR.IM] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.SR] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]
Abstract

International audience; Accurate measurements of Solar Spectral Irradiance (SSI) are of primary importance for a better understanding of solar physics and of the impact of solar variability on climate (via Earth's atmospheric photochemistry). The acquisition of a top of atmosphere reference solar spectrum and of its temporal and spectral variability during the unusual solar cycle 24 is of prime interest for these studies. These measurements are performed since April 2008 with the SOLSPEC spectro-radiometer from the far ultraviolet to the infrared (166 nm to 3088 nm). This instrument, developed under a fruitful LATMOS/BIRA-IASB collaboration, is part of the Solar Monitoring Observatory (SOLAR) payload, externally mounted on the Columbus module of the International Space Station (ISS). The SOLAR mission, with its actual 8 years duration, will cover almost the entire solar cycle 24. We present here the in-flight operations and performances of the SOLSPEC instrument, including the engineering corrections, calibrations and improved know-how procedure for aging corrections. Accordingly, a SSI reference spectrum from the UV to the NIR will be presented, together with its UV variability, as measured by SOLAR/SOLSPEC. Uncertainties on these measurements and comparisons with other instruments will be briefly discussed.

Published
2016

46. Halogens as tracers of protosolar nebula material in comet 67P/Churyumov–Gerasimenko

Author

Dhooghe, Frederik, primary, De Keyser, Johan, additional, Altwegg, Kathrin, additional, Briois, Christelle, additional, Balsiger, Hans, additional, Berthelier, Jean-Jacques, additional, Calmonte, Ursina, additional, Cessateur, Gaël, additional, Combi, Michael R., additional, Equeter, Eddy, additional, Fiethe, Björn, additional, Fray, Nicolas, additional, Fuselier, Stephen, additional, Gasc, Sébastien, additional, Gibbons, Andrew, additional, Gombosi, Tamas, additional, Gunell, Herbert, additional, Hässig, Myrtha, additional, Hilchenbach, Martin, additional, Le Roy, Léna, additional, Maggiolo, Romain, additional, Mall, Urs, additional, Marty, Bernard, additional, Neefs, Eddy, additional, Rème, Henri, additional, Rubin, Martin, additional, Sémon, Thierry, additional, Tzou, Chia-Yu, additional, and Wurz, Peter, additional

Published
2017
Full Text
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47. Evidence for distributed gas sources of hydrogen halides in the coma of comet 67P/Churyumov–Gerasimenko

Author

De Keyser, Johan, primary, Dhooghe, Frederik, additional, Altwegg, Kathrin, additional, Balsiger, Hans, additional, Berthelier, Jean-Jacques, additional, Briois, Christelle, additional, Calmonte, Ursina, additional, Cessateur, Gaël, additional, Combi, Michael R., additional, Equeter, Eddy, additional, Fiethe, Björn, additional, Fuselier, Stephen, additional, Gasc, Sébastien, additional, Gibbons, Andrew, additional, Gombosi, Tamas, additional, Gunell, Herbert, additional, Hässig, Myrtha, additional, Le Roy, Léna, additional, Maggiolo, Romain, additional, Mall, Urs, additional, Marty, Bernard, additional, Neefs, Eddy, additional, Rème, Henri, additional, Rubin, Martin, additional, Sémon, Thierry, additional, Tzou, Chia-Yu, additional, and Wurz, Peter, additional

Published
2017
Full Text
View/download PDF

48. Effect of porosity and non-planarity on icy grain surface chemistry in molecular clouds

Author

AGU Fall Meeting, Maggiolo, Romain, Cessateur, Gaël, Bonnal, Enzo, Dumontier, Meven, De Keyser, Johan, Dhooghe, Frederik, Gibbons, Andrew, Gunell, H., Mousis, Olivier, Vaeck, Nathalie, Loreau, Jérôme, AGU Fall Meeting, Maggiolo, Romain, Cessateur, Gaël, Bonnal, Enzo, Dumontier, Meven, De Keyser, Johan, Dhooghe, Frederik, Gibbons, Andrew, Gunell, H., Mousis, Olivier, Vaeck, Nathalie, and Loreau, Jérôme

Abstract

info:eu-repo/semantics/nonPublished

Published
2016

49. Hydrogen halides in the coma of 67P

Author

Comets: a new vision after Rosetta/Philae, Dhooghe, Frederik, Altwegg, Kathrin, Berthelier, Jean Jacques, Briois, Christelle, Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., De Keyser, Johan, Equeter, Eddy, Fiethe, Björn, Fray, Nicolas, Fuselier, Stephen Anthony, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Hilchenbach, Martin, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., Wurz, Peter, Comets: a new vision after Rosetta/Philae, Dhooghe, Frederik, Altwegg, Kathrin, Berthelier, Jean Jacques, Briois, Christelle, Calmonte, Ursina, Cessateur, Gaël, Combi, Michael M.R., De Keyser, Johan, Equeter, Eddy, Fiethe, Björn, Fray, Nicolas, Fuselier, Stephen Anthony, Gibbons, Andrew, Gombosi, Tamás I., Gunell, H., Hässig, Myrtha, Hilchenbach, Martin, Le Roy, Léna, Maggiolo, Romain, Mall, Urs, Marty, Bernard, Neefs, Eddy, Rème, Henri, Rubin, Martin, Sémon, T., and Wurz, Peter

Abstract

info:eu-repo/semantics/nonPublished

Published
2016

50. Photochemistry of forbidden oxygen lines in the coma of 67P/Churyumov-Gerasimenko

Author

From Giotto to Rosetta, 50th ESLAB conference (Leiden), Cessateur, Gaël, De Keyser, Johan, Maggiolo, Romain, Gibbons, Andrew, Gronoff, Guillaume, Gunell, H., Dhooghe, Frederik, Loreau, Jérôme, Vaeck, Nathalie, Altwegg, Kathrin, Bieler, André, Briois, Christelle, Calmonte, Ursina, Combi, Michael M.R., Fiethe, Björn, Fuselier, Stephen Anthony, Gombosi, Tamás I., Hässig, Myrtha, Le Roy, Léna, Neefs, Eddy, Rubin, Martin, Sémon, T., From Giotto to Rosetta, 50th ESLAB conference (Leiden), Cessateur, Gaël, De Keyser, Johan, Maggiolo, Romain, Gibbons, Andrew, Gronoff, Guillaume, Gunell, H., Dhooghe, Frederik, Loreau, Jérôme, Vaeck, Nathalie, Altwegg, Kathrin, Bieler, André, Briois, Christelle, Calmonte, Ursina, Combi, Michael M.R., Fiethe, Björn, Fuselier, Stephen Anthony, Gombosi, Tamás I., Hässig, Myrtha, Le Roy, Léna, Neefs, Eddy, Rubin, Martin, and Sémon, T.

Abstract

info:eu-repo/semantics/nonPublished

Published
2016

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