Transcript "TARANIS - a Satellite Project dedicated to the Physics of TLEs and

TARANIS - a satellite project dedicated
to the physics of TLEs and TGFs
F. Lefeuvre1, E. Blanc2, J.L. Pinçon1 and the TARANIS team*
1 LPCE /CNRS – Univ Orléans, Orléans, France,
2 CEA, DASE/LDG, Bruyères le Châtel, France
* E. Blanc, J. Blecki, T. Farges, H. de Feraudy, W.C. Feldman, U.S. Inan, F.
Lefeuvre, R.P. Lin, M. Parrot, T. Neubert, R. Pfaff, J.L. Pinçon, Z.
Nemecek, J.L. Rauch, R. Roussel-Dupré, O. Santolik, M. Sato, D.M. Smith,
M. Suzuki, Y. Takahashi
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Objective of the paper
(1) to show how the TARANIS instruments may
contribute to fulfill very general science objectives
related to the physics of TLEs and TGFs
(2) to point out required complementary
measurements from
- other spacecraft
- ground-based stations
- balloon-borne experiments
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Science Objectives

Advance physical understanding of the links between
TLEs, TGFs and environmental conditions (lightning activity,
geomagnetic activity, atmosphere/ionosphere coupling, occurrence of
Extensive Atmospheric Showers, etc.).

Identify other potential signatures of impulsive transfers
of energy (electron beams, associated electromagnetic or/and
electrostatic fields) and provide inputs to test generation
mechanisms

Provide inputs for the modeling of the effects of TLEs,
TGFs and bursts of precipitated and accelerated electrons
(lightning induced electron precipitation, runaway electron
beams) on the Earth’s atmosphere.
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TLEs and TGFs observations
Locate geographical positions and altitudes of TLEs
and TGFs source regions
Model variations with LT, season, activity indices,
etc.
Environmental conditions
Identify parent lightning flashes and associated EM
emissions
Investigate possible correlations with cosmic rays,
micrometeorites, volcanoes, etc.
Transfers of energy between
the radiation belts, the
ionosphere and the
atmosphere
Detect and characterize burst of precipitated
electrons (LEPs) and of accelerated electrons (RBs)
TLEs and TGFs generation
mechanisms
Provide input data (TLEs and TGFs source regions,
association with lightning activities and other
environmental parameters like AES, bursts of
precipitated and accelerated electrons) to test
generation mechanisms
Contribution to the modeling
of the effects on the
atmosphere and on the global
electric circuit
Provide information on sources of energy (TLEs,
TGFs, bursts of precipitated and accelerated
electrons) or/and on large scale ionospheric
perturbations
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INSTRUMENTS
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The scientific payload is operated as a single instrument
The objective is:
▪ to make a low time resolution survey of the optical
and field/particle events at medium and low latitudes,
▪ under alert, to record well synchronized high resolution data
(Event).
Alerts may be triggered by the detection of a priority event
(TLEs, TGFs, electron beams, or burst of electromagnetic or
electrostatic wave) .
A Multi EXperiment Interface Controller (MEXIC) is in charge of the
on-board management (M. Parrot – LPCE/CNRS (F) + CBK (P)).
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Operations
■ ON , - 60° < lat < 60°
■ Optical measurements, night time, SAA excluded
■ X and gamma rays, SAA excluded
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Event mode
triggered when a priority event is detected on 1 instrument
all instruments record and transmit high resolution data
Survey mode
Wave instruments
continuous monitoring, transmission of low resolution data
Optical, particle and X& gamma ray instruments: except in
excluded zones, continuous monitoring, transmission of
compressed data
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MCP (Micro Cameras and Photometers) – E. Blanc -CEA/LDG
(F) + Univ Tohoku-Hokkaido, Jaxa (J)
Objectives
- identification and characterization of TLEs
- locate source regions
Strategy
- observations at several wavelengths at Nadir
- triggering of alert signals
Equipment
Cameras
- lightning camera : visible and near-infrared (600-900 nm)
- TLE camera: band 762 ± 5 nm
30 images/second, with 512x512 pixels per image.
observation zone ~ 500 km, spatial resolution at ground ~ 1 km
Photometers
- 762 ± 5 nm, 337 ± 5 nm, 150 to 280 nm (obs. disk of 275 km radius)
- 600 to 900 nm (lightning measurements, obs. disk of 700 km).
Flux of photons sampled at 20 kHz.
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XGRE (X-ray, Gamma-ray and Relativistic Electron
Experiment) - D. Lawrence – JHUAPL (USA) + DNSC (D), UC Berkeley
& Santa Cruz, Planetary Science Institute, SciTech Solutions (USA)
Objectives
- measurement of the total energy released per event
- estimation of the altitude at which the burst is initiated
- estimation of the latitude and LT dependent factors that
control the evolution of the burst event
Strategy
- Measurements of photon energies 20 keV - 10 MeV
- Identification of relativistic electrons (1 Mev – 10 Mev)
- provide alert signals
Equipment
Three rectangular, 10 mm-thick CsI(Na) scintillator sheets,
each having 300 cm2 area. The plastic scintillator acts as a
partial anticoincidence shield and a dE/dX identifier of
relativistic electrons
One sensor will face downward and two will face upwards
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IDEE (Energetic Electrons) - J.A. Sauvaud – CESR/CNRS
(F) + Univ. Prague (Cz)
Objectives
- Pitch-angle Distribution of Radiation Belt Electrons
- Relativistic Runaway Electrons (RRE)
- Lightning-induced Electron Precipitation (LEP)
Strategy
- provide high resolution energetic electron spectra (70 keV - 4
MeV) in a large dynamic range of fluxes, and pitch-angle
distribution,
- provide alert signal for RBs
Equipment
Two spectrometers, one with a sight axis making an angle of
60° with the Nadir, the second making an angle of 30° with the
anti-Nadir direction
Angular direction better than 35°
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IME-BF
(Low frequency Electric Field)
- H. de
Feraudy – CETP/CNRS (F) + GSFC (USA)
Objectives
- identification of the 0+ whistlers associated with the
parent lightning
- monitoring of the EM environment (natural and manmade emissions, EM signatures of electron beams)
- estimation of the characteristic parameters of the local
thermal plasma (fpe, variations in the ion density)
Strategy
- measurement of the E field fron DC to 1 MHz
- ion probe
Equipment
- 1 electric (DEMETER) antenna (spheres located at the tip
of 4 m booms)
- 1 ion probe (C/NOFS)
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IME-HF (HF/VHF Electric Field)
- J.L. Rauch
LPCE/CNRS (F) + Univ. Prague, IAP (Cz)
Objectives
- detection of HF/VHF EM signatures of lightnings
- monitoring of HF/VHF natural (TIPPs) and man-made
emissions (broadcast transmitters)
- contribution to the estimation of polarization
characteristics of HF/VHF emissions
Strategy
- E field measurement in the frequency band 100 kHz – 35
MHz
- on-board data selection
Equipment
- 2 monopoles of 1 m length each (3m tip to tip distance)
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IMM
(Low frequency magnetic field)
- J.L. Pinçon
LPCE/CNRS (F) + Univ Stanford (USA)
Objectives
- in common with IME/BF (but for distinction between EM
and ES signals) : (i) identification of the 0+ whistlers
associated with the parent lightning, (ii) monitoring of the
EM environment (natural and man-made emissions, EM
signatures of electron beams)
- below 20 kHz, estimation of the propagation
characteristics of EM waves (propagation mode, k vector)
- Statistical study of 0+ whistlers
Strategy
- B field measurement in the band 0.1 Hz – 1 MHz
- automatic detection of the 0+ whistlers (from E or field)
Equipment
- 3 axis magnetic sensor up to 20 kHz
- 1 axis magnetic sensor up to 1 MHz
- 0+ whistler detector
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TARANIS contribution to major
scientific issues
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Source regions of TLEs and TGFs

With MCP, identification of sprites halos and elves, and of their source
regions (pb for low altitude events such as blue jets ?) at given LTs.

With XGRE, identification of TGFs and of their source regions

With wave measurements, identification of 0+ whistler associated with
parent lightning (MF/HF/VHF band included)

Complementary measurements:
- at ground (lightning detection network, sferics, TLEs)
- on balloon borne experiments (low altitude TGFs, low altitude
TLEs)
- on board other spacecraft (in particular LT coverage)
- etc.
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Characterization of EM signatures

Monitoring of natural and man made emissions in a wide frequency
bands (DC - 35 MHz)

Discrimination between ES and EM emissions in the 0.1 Hz – 1 MHz
band

Estimation of the propagation characteristics up to 20 kHz

Complementary measurements :
- at ground (ELF signatures, complementarities in the
ELF/VLF/HF/VHF lightning detection at ground and in space)
- at ground and on balloon borne experiments (characterization of
the E fields above thunderstorms)
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Estimation of input parameters for generation
models

Characterization of the TLEs and TGFs source regions

Estimation of the deposit of energy by EM waves in the lower layers of
ionosphere

(expected) identification of runaway electron beams

Energy and ionization sources associated with precipitated electrons

Complementary measurements:
- at ground and on balloon born experiments, energy sources provided by
Extensive Atmospheric Showers
- at ground, energy released in infrasound
- other spacecraft measurements
- etc.
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Estimation of characteristic parameters of the
D and E layers

Parameters derived from the observation at the satellite altitude of:
- the thermal plasma parameters
- the EM power spectral density

Complementary measurements
- at ground (EM power spectral density, ground-based
ionospheric instruments)
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Estimation of input parameters for modeling
effects on the atmosphere

Characterization of sources of energy (TLEs, TGFs, bursts of
precipitated and accelerated electrons, EMP)

Information on local plasma parameters

Complementary instruments:
- ground-based, balloon-based and spacecraft based
measurements of atmospheric species (NOx and O3) variations
- etc.
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