Thierry Dudok de Wit
A5081850741- Solar and Space Plasma Dynamics
- Ionosphere and magnetosphere dynamics
- Astro and Planetary Science
- Geomagnetism and Paleomagnetism Studies
- Solar Radiation and Photovoltaics
- Stellar, planetary, and galactic studies
- Atmospheric Ozone and Climate
- Geophysics and Gravity Measurements
- Earthquake Detection and Analysis
- Magnetic confinement fusion research
- Planetary Science and Exploration
- Atmospheric and Environmental Gas Dynamics
- Calibration and Measurement Techniques
- Spacecraft Design and Technology
- Atmospheric chemistry and aerosols
- Fluid Dynamics and Turbulent Flows
- Global Energy and Sustainability Research
- History and Developments in Astronomy
- Magnetic Field Sensors Techniques
- Laser-Plasma Interactions and Diagnostics
- Photovoltaic System Optimization Techniques
- Seismic Waves and Analysis
- Blind Source Separation Techniques
- Spectroscopy and Chemometric Analyses
- Complex Systems and Time Series Analysis
Université d'Orléans
2016-2025
Centre National de la Recherche Scientifique
2016-2025
International Space Science Institute
2023-2025
Space Research and Technology Institute
2025
Bulgarian Academy of Sciences
2025
Korea Astronomy and Space Science Institute
2025
Laboratoire de Physique et Chimie de l’Environnement et de l’Espace
2014-2023
Laboratoire Chimie de l'Environnement
2000-2022
University of Michigan–Ann Arbor
2021
1366 Technologies (United States)
2021
Abstract. This paper describes the recommended solar forcing dataset for CMIP6 and highlights changes with respect to CMIP5. The is provided radiative properties, namely total irradiance (TSI), spectral (SSI), F10.7 index as well particle forcing, including geomagnetic indices Ap Kp, ionization rates account effects of protons, electrons, galactic cosmic rays. first time that a recommendation solar-driven has been CMIP exercise. datasets are at daily monthly resolution separately...
The lack of long and reliable time series solar spectral irradiance (SSI) measurements makes an accurate quantification contributions to recent climate change difficult. Whereas earlier SSI observations models provided a qualitatively consistent picture the variability, by SORCE satellite suggest significantly stronger variability in ultraviolet (UV) range changes visible near-infrared (NIR) bands anti-phase with cycle. A number chemistry-climate model (CCM) simulations have shown that this...
The first two orbits of the Parker Solar Probe (PSP) spacecraft have enabled in situ measurements solar wind down to a heliocentric distance 0.17 au (or 36 Rs). Here, we present an analysis this data study turbulence at and its evolution out 1 au. While many features remain similar, key differences include: increased energy levels by more than order magnitude, magnetic field spectral index -3/2 matching that velocity both Elsasser fields, lower compressibility consistent with smaller...
One of the most striking observations made by Parker Solar Probe during its first solar encounter is omnipresence rapid polarity reversals in a magnetic field that otherwise mostly radial. These so-called switchbacks strongly affect dynamics field. We concentrate here on their macroscopic properties. First, we find these structures are self-similar, and have neither characteristic magnitude, nor duration. Their waiting time statistics shows evidence for aggregation. The associated long...
We report progress on the ongoing recalibration of Wolf sunspot number (SN) and Group (GN) following release version 2.0 SN in 2015. This constitutes both an update efforts reported 2016 Topical Issue Solar Physics a summary work by International Space Science Institute (ISSI) Team formed 2017 to develop optimal GN re-construction methods while continuing expand historical database. Significant has been made database side more is needed bring various proposed (primarily) reconstruction...
Abstract The dissipation of turbulence in astrophysical systems is fundamental to energy transfer and heating environments ranging from the solar wind corona accretion disks intracluster medium. Although turbulent relatively well understood fluid dynamics, plasmas often exhibit exotic behaviour, arising lack interparticle collisions, which complicates these systems. Recent observations by NASA’s Parker Solar Probe mission inner heliosphere have shed new light on role ion cyclotron resonance...
Heat transport in the solar corona and wind is still a major unsolved astrophysical problem. Because of key role played by electrons, electron density temperature(s) are important prerequisites for understanding these plasmas. We present such situ measurements along two first encounters Parker Solar Probe (PSP), between 0.5 0.17 AU from Sun, revealing different states emerging near activity minimum. These preliminary results obtained simplified analysis plasma quasi-thermal noise (QTN)...
Abstract Measurements of the near-Sun solar wind by Parker Solar Probe have revealed presence large numbers discrete Alfvénic impulses with an anti-sunward sense propagation. These are similar to those previously observed near 1 au, in high speed streams over Sun’s poles and at 60 radii. At 35 radii, however, they typically shorter sharper than seen elsewhere. In addition, these spikes occur “patches” there also clear periods within same stream when do not occur; timescale patches might be...
The Radio and Plasma Waves (RPW) instrument on the ESA Solar Orbiter mission is described in this paper. This designed to measure in-situ magnetic electric fields waves from continuous a few hundreds of kHz. RPW will also observe solar radio emissions up 16 MHz. primary importance science requirements since it essential answer three four overarching objectives. In addition exchange on-board data with other instruments order process algorithms for interplanetary shocks type III langmuir detections.
Abstract Parker Solar Probe ( PSP ) observations during its first encounter at 35.7 R ⊙ have shown the presence of magnetic field lines that are strongly perturbed to point they produce local inversions radial field, known as switchbacks. Their counterparts in solar wind velocity enhancements speed, or jets, displaying (in all components) velocity–magnetic correlation typical large amplitude Alfvén waves propagating away from Sun. Switchbacks and jets previously been observed over a wide...
Abstract Switchbacks (rotations of the magnetic field) are observed on Parker Solar Probe . Their evolution, content, and plasma effects studied in this paper. The solar wind does not receive a net acceleration from switchbacks that it encountered upstream observation point. typical switchback rotation angle increased with radial distance. Significant Poynting fluxes existed inside, but outside, switchbacks, dependence flux amplitude location is explained quantitatively as being proportional...
Understanding the physical processes in solar wind and corona which actively contribute to heating, acceleration, dissipation is a primary objective of NASA's Parker Solar Probe (PSP) mission. Observations coherent electromagnetic waves at ion scales suggests that linear cyclotron resonance non-linear are dynamically relevant inner heliosphere. A wavelet-based statistical study first perihelion encounter PSP demonstrates presence transverse resonant observed 30-50\% radial field intervals....
Magnetic reconnection in current sheets converts magnetic energy into particle energy. The process may play an important role the acceleration and heating of solar wind close to Sun. Observations from Parker Solar Probe provide a new opportunity study this problem, as it measures at unprecedented distances During 1st orbit, PSP encountered large number through perihelion 35.7 radii. We performed comprehensive survey these found evidence for 21 exhausts. These exhausts were observed...
Abstract During Parker Solar Probe ’s first orbit, the solar wind plasma was observed in situ closer than ever before, perihelion on 2018 November 6 revealing a flow that is constantly permeated by large-amplitude Alfvénic fluctuations. These include radial magnetic field reversals, or switchbacks, seem to be persistent feature of young wind. The measurements also reveal very strong, unexpected, azimuthal velocity component. In this work, we numerically model corona during encounter, solving...
Abstract Parker Solar Probe (PSP), NASA’s latest and closest mission to the Sun, is on a journey investigate fundamental enigmas of inner heliosphere. This paper reports initial observations made by Analyzer for Ions (SPAN-I), one instruments in Wind Electrons Alphas Protons instrument suite. We address presence secondary proton beams concert with ion-scale waves observed FIELDS, electromagnetic fields show two events from PSP’s second orbit that demonstrate signatures consistent...
Solar Orbiter is the first space mission observing solar plasma both in situ and remotely, from a close distance, out of ecliptic. The ultimate goal to understand how Sun produces controls heliosphere, filling System driving planetary environments. With six remote-sensing four in-situ instrument suites, coordination planning operations are essential address following top-level science questions: (1) What drives wind where does coronal magnetic field originate? (2) How do transients drive...
We consider 2D joint distributions of normalized residual energy, σr(s, t), and cross helicity, σc(s, during one day Parker Solar Probe's (PSP's) first encounter as a function wavelet scale s. The broad features the are similar to previous observations made by Helios in slow solar wind, namely well-correlated fairly Alfvénic except for population with negative helicity that is seen at shorter scales. show this due presence magnetic switchbacks, or brief periods where field polarity reverses....
Direct evidence of an inertial-range turbulent energy cascade has been provided by spacecraft observations in heliospheric plasmas. In the solar wind, average value derived heating rate near 1 au is $\sim 10^{3}\, \mathrm{J\,kg^{-1}\,s^{-1}}$, amount sufficient to account for observed departures from adiabatic expansion. Parker Solar Probe (PSP), even during its first encounter, offers opportunity compute, a similar fashion, fluid-scale decay rate, much closer corona than any prior in-situ...
We discuss the solar wind electron temperatures Te as measured in nascent by Parker Solar Probe during its first perihelion pass. The measurements have been obtained fitting high-frequency part of quasi-thermal noise spectra recorded Radio Frequency Spectrometer. In addition we compare these with those electrostatic analyzer discussed Halekas et al. These observations show an anticorrelation between and bulk speed V: this is most likely remnant well-known mapping observed at 1 au beyond fast...
Abstract The first radial alignment between Parker Solar Probe and Orbiter spacecraft is used to investigate the evolution of solar wind turbulence in inner heliosphere. Assuming ballistic propagation, two 1.5 hr intervals are tentatively identified as providing measurements same plasma parcels traveling from 0.1 1 au. Using magnetic field both spacecraft, properties assessed. Magnetic spectral density, flatness, high-order moment scaling laws calculated. Hilbert–Huang transform additionally...
Parker Solar Probe (PSP) data recorded within a heliocentric radial distance of 0.3 AU have revealed magnetic field dominated by Alfv\'enic structures that undergo large local variations or even reversals the field. They are called switchbacks, they consistent with folds in lines same sector, and associated velocity spikes during an otherwise calmer background. thought to originate either low solar atmosphere through reconnection processes, result from evolution turbulence shears expanding...
In the lower solar coronal regions where magnetic field is dominant, Alfven speed much higher than wind speed. contrast, near-Earth strongly super-Alfvenic, i.e., greatly exceeds The transition between these regimes classically described as "Alfven point" but may in fact occur a distributed critical region. NASA's Parker Solar Probe (PSP) mission has entered this region, it follows series of orbits that gradually approach more closely to sun. During its 8th and 9th encounters, at distance 16...
Abstract. The solar forcing prepared for Phase 6 of the Coupled Model Intercomparison Project (CMIP6) has been used extensively in climate model experiments and tested various intercomparison studies. Recently, an International Space Science Institute (ISSI) working group established to revisit recommendations, based on lessons learned from CMIP6, assess new datasets that have become available, order define a road map building revised extended historical dataset upcoming 7 CMIP. This paper...