A5080196283- Ionosphere and magnetosphere dynamics
- Atmospheric Ozone and Climate
- Impact of Light on Environment and Health
- Dark Matter and Cosmic Phenomena
- Earthquake Detection and Analysis
- Atomic and Subatomic Physics Research
- Atmospheric aerosols and clouds
- Solar and Space Plasma Dynamics
- Astrophysics and Cosmic Phenomena
- Atmospheric and Environmental Gas Dynamics
- Geophysics and Sensor Technology
- Planetary Science and Exploration
- Spacecraft Design and Technology
- Radioactive Decay and Measurement Techniques
- Infrared Target Detection Methodologies
- Radiation Therapy and Dosimetry
- Particle physics theoretical and experimental studies
- Ocular and Laser Science Research
- Space Science and Extraterrestrial Life
- Spectroscopy and Laser Applications
Université Grenoble Alpes
2020-2023
Royal Belgian Institute for Space Aeronomy
2022-2023
Centre National de la Recherche Scientifique
2020-2022
Institut de Planétologie et d'Astrophysique de Grenoble
2020-2022
Karlsruhe Institute of Technology
2017
Max Planck Institute for Radio Astronomy
2017
University of Alabama
2017
University of Bonn
2017
Aurora observations at mid-latitudes are rare but not exceptional. The aurorae usually seen as diffuse red illuminations of the sky above Northern (respectively Southern) horizon in northern and southern hemispheres) because they occur much higher latitude their lower parts (green, purple, blue) fall below horizon. However, while high-latitude sightings blue frequent, have rarely been reported. During night September 24 to 25, 2023, a series was from viewpoint 48.3 ◦ geographic north 1.2...
The so-called "GeV-excess" of the diffuse Galactic gamma-ray emission is studied with a spectral template fit based on energy spectra. templates can be obtained in data-driven way from data, which avoids use emissivity models to subtract standardbackground processes data. Instead, one determine these backgrounds simultaneously any "signals" sky direction, including disk and center. Using two hypothesis were tested: dark matter (DM) assuming excess caused by DM annihilation molecular cloud...
We present here observations of the polarisation four auroral lines in oval and polar cusp using a new ground polarimeter called Petit Cru . Our results confirm already known red line, show for first time that three other observed (namely 557.7 nm, 391.4 nm 427.8 nm) are polarised as well up to few percent. several circumstances, this is linked local magnetic activity state ionosphere through electron density measured with EISCAT. However, we also contribution light pollution from nearby...
A polarised radiative transfer model (POMEROL) has been developed to compute the polarisation measured by a virtual instrument in given nocturnal environment. This single-scattering recreates real-world conditions (among them atmospheric and aerosol profiles, light sources with complex geometries at ground sky, terrain obstructions). It successfully tested mid-latitudes where sky emissions are of weak intensity. We show series comparisons between POMEROL predictions measurements during two...
In October 2023, a spectrograph has been permanently installed at the Skibotn Observatory (Norway) in order to regularly monitor auroral spectrum between ~ 400 and 700 nm with time resolution of 30 seconds. Using 300 lines/mm grating slit 100 width, wavelength is approximately 0.3 nm.  The instrument pointing field-aligned. characteristics will be provided as well examples spectra obtained during quiet, moderate strong geomagnetic conditions.  A relative flux calibration...
We review the last advances in study of upper atmospheric emissions polarisation. Since 2008, observations and modeling initiatives aimed at detecting understanding auroral emission In recent years, this field saw major advances, which confirm ionospheric origin Polarisation has been observed all four main visible lines (the red (630 nm), green (557.7 blue (427.8) purple (391.4 nm)), several geomagnetic activity levels confirmed for N2+ through laboratory experiments. However, polarisation...
The Fermi-LAT data reveal an excess of diffuse gamma-rays at energies around 2 GeV in the direction Galactic center. has been studied by many groups and is observed above expectation for gamma-ray emission from cosmic ray interactions with in- terstellar material (π0 production protons bremstrahlung electrons interstellar gas) radiation field (inverse Compton scattering field). In addition to these standard components we find evidence two additional processes: π 0 sources during acceleration...
It is now established that auroral emissions as measured from the ground are polarised. The question of information given by this polarisation still to be explored. This article shows results a coordinated campaign between an optical polarimeter and several ground-based instruments, including magnetometers, EISCAT VHF radar, complementary luminance meters in visible domain (Ninox). We show E region, potential indicator ionospheric currents, velocity, dynamics.
Abstract A series of experiments have shown recently that several auroral lines are polarized, when observed from the ground. However, this polarization may be caused by indirect light sources (from ground or sky) scattered in lower atmosphere Rayleigh and Lorenz‐Mie scattering, during crossing ionospheric current sheets. Here, we present measurements blue (427.8 nm) purple (391.4 emissions a laboratory confined setting excludes any pollution scattering. We show both at level comparable to...
The measurements of the polarization auroral emission lines in Earth’s atmosphere is particular interest for understanding upper but also potential space weather applications. Emissions from oxygen red line at 630 nm has been observed polarized since 2008 and origin likely due to imbalance Zeeman sublevels, which comes magnetospheric electrons precipitating with a pitch angle distribution more or less aligned local magnetic field. blue 427.8 N2+, green light 557.7 atomic have their...
In the last decade, several instruments have been developped to measure auroral light polarisation. However, its study has faced issue of anthropic pollution and scattering in lower atmosphere (Bosse et al., 2020). To overcome this challenge, methods were used, until now, most succesfull was use a polarised radiative transfer model 2022) identify contribution. However during past year new look at data revealed that pulsating aurorae are polarised, polarisation carries lot information. The...