Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
Description
A natural lightning flash is a powerful phenomenon, still not totally understood. Lightning mapping techniques, like difference of time-of-arrival technique in the VHF domain, provide key characterization of the development of both Intra-Cloud (IC) and Cloud-to-ground (CG) lightning flashes. Combined to cloud remote sensing observations, the lightning flash can be replaced in its environmental context. However questions remain on the physical processes that trigger a lightning flash, as the ambient macroscopic electric field inside the cloud is typically one order of magnitude less than that required for dielectric breakdown. One hypothesis currently considered by the community is that a lightning flash can be triggered by an avalanche of runaway electrons created by cosmic ray-induced extensive air showers with energy in excess of 1016 eV (Gurevich et al, 1992). On the other hand, it has been evidenced that terrestrial gamma-ray flashes may be produced in association with natural lightning flashes (e.g. Cummer et al., 2005; Splitt et al., 2010). Consequently further investigations are required to not only document but also to understand the complex physical processes involved here through a multi-disciplinary study that will require both observations and modeling exercises. The LIghtning and COsmic Rays in Natural Environment project (LICORNE) aims at gathering French Scientists working in High-energy Particle and Atmospheric Sciences on a common project dedicated to the study of the impact of natural cosmic rays on the occurrence of natural lightning flashes and on the characterization of high-energy particles radiated during natural lightning flashes. In its first year, the LICORNE project will:
i) perform a rather exhaustive literature review on the interaction between cosmic rays and lightning flashes,
ii) identify strengths and weaknesses of the Consortium in its current composition,
iii) explore available lightning and air shower observations above the CODALEMA site during the
recent years to help define a realistic Science Plan that will drive the development phase of the project, including an observational strategy combining relevant instrumentation, and a modeling
strategy in preparation for the interpretation of the observations.
A preliminary approach could be based on long-term collection of detailed records of air showers
and lightning flashes for storms passing above a single state-of-the-art instrumental site - already existing or to build - and on the analysis of temporal and spatial correlations in the observations to provide key inputs for modeling investigations coupling high-energy particle physics and lightning phenomenology. The LICORNE project includes physicists of the Terrestrial Gamma-ray Flashes (TGFs) French community for shared analysis using lightning and cosmic rays data but no gamma imager is foreseen in this project.
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
but de la réunion, objectifs du projet, quelle observable
d’une corrélation RC/éclairs ?
10 kE+2 kE disponibles : mesureur de champ ? autre ?
tour de table
2 possibilités : corrélation éclair/passage d'une gerbe (temps/espace) et modification du champ électrique des gerbes en conditions orageuses
Orateur:
Benoît Revenu(subatech)
Transparents
09:50
→
11:00
Théoriesalle Nord
salle Nord
Nançay
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
09:50
Les rayons cosmiques20m
très bref sur : spectre en énergie, source
description de la gerbe atmosphérique : particules secondaires, distribution en énergie, géométrie
reconstruction des paramètres du primaire : cœur, triangulation, résolutions
Orateur:
Benoît Revenu(subatech)
Transparents
10:10
Emission radio dans les gerbes20m
Orateur:
Benoît Revenu(subatech)
Transparents
11:00
→
11:15
café
15m
salle Nord
salle Nord
Nançay
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
11:15
→
11:45
Instrumentationsalle Nord
salle Nord
Nançay
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
11:15
Instruments à Nançay (1/2)30m
présentation générale
puis :
scintillateurs : description, signaux, identification des gerbes, trigger
stations autonomes 10-200 MHz : description, trigger, transitoires, identification des gerbes
Orateur:
Lilian Martin(subatech)
Transparents
11:45
→
12:15
Discussionssalle Nord
salle Nord
Nançay
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
12:15
→
13:25
Pause repassalle Nord
salle Nord
Nançay
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
13:25
→
14:30
Théoriesalle Nord
salle Nord
Nançay
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
13:30
Orages et éclairs30m
comment ça marche ? physique de l'éclair, quelles mesures ? Données Météorage.
Orateur:
Stéphane Pedeboy
Transparents
14:00
Lien orages/rayons cosmiques30m
modèle de Gurevich
Orateur:
Éric Defer
Transparents
14:30
→
15:10
Instrumentationsalle Nord
salle Nord
Nançay
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
14:30
Instruments à Nançay (2/2)30m
stations basse fréquence 1-10 MHz : description, trigger, allure des données
antenne tripole 10-200 MHz : description, trigger, allure des données
station météo
Orateur:
M.Richard Dallier(SUBATECH)
Transparents
15:00
Mesureur de champ10m
Orateur:
Benoît Revenu(subatech)
Transparents
15:10
→
15:30
Mesures infrason20msalle Nord
salle Nord
Nançay
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
Orateur:
Thomas Farges
Transparents
15:30
→
17:00
Data & analysesalle Nord
salle Nord
Nançay
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France
17:00
→
17:15
café
15m
salle Nord
salle Nord
Nançay
Station de Radioastronomie de Nançay
route de Souesmes
18330 Nançay, France