PHEBUS: A double ultraviolet spectrometer to observe Mercury's exosphere
Eric Chassefière
(1, 2)
,
Jean-Luc Maria
(1)
,
Jean-Pierre Goutail
(1)
,
Eric Quémerais
(3, 4)
,
François Leblanc
(4)
,
S. Okano
(5)
,
I. Yoshikawa
(6)
,
O. Korablev
(7)
,
V. Gnedykh
(7)
,
G. Naletto
(8)
,
P. Nicolosi
(8)
,
M.-G. Pelizzo
(8)
,
Jean-Jacques Correia
(1)
,
S. Gallet
(9)
,
C. Hourtoule
(9)
,
Pierre-Olivier Mine
(4)
,
Christophe Montaron
(1)
,
Nicolas Rouanet
(1)
,
Jean-Baptiste Rigal
(1)
,
G. Muramaki
(6)
,
K. Yoshioka
(6)
,
O. Kozlov
(7)
,
V. Kottsov
(7)
,
P. Moisseev
(10)
,
N. Semena
(7)
,
Jean-Loup Bertaux
(4)
,
M.-Th. Capria
(11)
,
J. Clarke
(12)
,
Gabriele Cremonese
(12, 13)
,
Dominique C. Delcourt
(9)
,
A. Doressoundiram
(14, 15)
,
S. Erard
(15)
,
R. Gladstone
(16)
,
M. Grande
(17)
,
D. Hunten
(18)
,
W. Ip
(19)
,
V. Izmodenov
(20)
,
Albert Jambon
(21)
,
R. Johnson
(22)
,
E. Kallio
(23)
,
R. Killen
(24)
,
Rosine Lallement
(4)
,
J. Luhmann
(25)
,
M. Mendillo
(13)
,
A. Milillo
(26)
,
H. Palme
(27)
,
A. Potter
(28)
,
S. Sasaki
(6)
,
D. Slater
(18)
,
A. Sprague
(16)
,
A. Stern
(18)
,
Nicolas Yan
(29)
1
LATMOS -
Laboratoire Atmosphères, Milieux, Observations Spatiales
2 IDES - Interactions et dynamique des environnements de surface
3 IAS - Institut d'astrophysique spatiale
4 HELIOS - LATMOS
5 Tohoku University [Sendai]
6 UTokyo - The University of Tokyo
7 IKI - Space Research Institute of the Russian Academy of Sciences
8 LUXOR - Laboratory for Ultraviolet and X-ray Optical Research [Padova]
9 IPSL - Institut Pierre-Simon-Laplace
10 Scientific Production Enterprise Astron Electronics
11 IASF-Roma - Istituto di Astrofisica Spaziale e Fisica cosmica - Roma
12 CSP - Center for Space Physics [Boston]
13 Department of Astronomy [Boston]
14 OP - Observatoire de Paris - Site de Paris
15 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique
16 LPL - Lunar and Planetary Laboratory [Tucson]
17 RAL - STFC Rutherford Appleton Laboratory
18 SwRI - Southwest Research Institute [San Antonio]
19 IANCU - Institute of Astronomy [Taiwan]
20 Department of Aeromechanics and Gas Dynamics [Moscow]
21 Laboratoire Magie
22 Engineering Physics Program [Charlottesville]
23 FMI - Finnish Meteorological Institute
24 Department of Astronomy [College Park]
25 SSL - Space Sciences Laboratory [Berkeley]
26 IFSI - Istituto di Fisica dello Spazio Interplanetario
27 Universität zu Köln = University of Cologne
28 NSO/Tucson - National Solar Observatory [Tucson]
29 SA - Service d'aéronomie
2 IDES - Interactions et dynamique des environnements de surface
3 IAS - Institut d'astrophysique spatiale
4 HELIOS - LATMOS
5 Tohoku University [Sendai]
6 UTokyo - The University of Tokyo
7 IKI - Space Research Institute of the Russian Academy of Sciences
8 LUXOR - Laboratory for Ultraviolet and X-ray Optical Research [Padova]
9 IPSL - Institut Pierre-Simon-Laplace
10 Scientific Production Enterprise Astron Electronics
11 IASF-Roma - Istituto di Astrofisica Spaziale e Fisica cosmica - Roma
12 CSP - Center for Space Physics [Boston]
13 Department of Astronomy [Boston]
14 OP - Observatoire de Paris - Site de Paris
15 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique
16 LPL - Lunar and Planetary Laboratory [Tucson]
17 RAL - STFC Rutherford Appleton Laboratory
18 SwRI - Southwest Research Institute [San Antonio]
19 IANCU - Institute of Astronomy [Taiwan]
20 Department of Aeromechanics and Gas Dynamics [Moscow]
21 Laboratoire Magie
22 Engineering Physics Program [Charlottesville]
23 FMI - Finnish Meteorological Institute
24 Department of Astronomy [College Park]
25 SSL - Space Sciences Laboratory [Berkeley]
26 IFSI - Istituto di Fisica dello Spazio Interplanetario
27 Universität zu Köln = University of Cologne
28 NSO/Tucson - National Solar Observatory [Tucson]
29 SA - Service d'aéronomie
François Leblanc
- Fonction : Auteur
- PersonId : 175354
- IdHAL : francois-leblanc69
- ORCID : 0000-0002-5548-3519
- IdRef : 223432296
S. Erard
- Fonction : Auteur
- PersonId : 183422
- IdHAL : stephane-erard
- ORCID : 0000-0002-9099-8366
- IdRef : 083612505
Albert Jambon
- Fonction : Auteur
- PersonId : 179930
- IdHAL : albert-jambon
- ORCID : 0000-0002-6124-5883
Résumé
Probing of Hermean exosphere by ultraviolet spectroscopy (PHEBUS) is a double spectrometer for the Extreme Ultraviolet range (55-155 nm) and the Far Ultraviolet range (145-315 nm) devoted to the characterization of Mercury's exosphere composition and dynamics, and surface-exosphere connections. This French-led instrument is implemented in a cooperative scheme involving Japan (detectors), Russia (scanner) and Italy (ground calibration). PHEBUS will address the following main scientific objectives relative to Mercury's exosphere: determination of the composition and the vertical structure of the exosphere; characterization of the exospheric dynamics: day to night circulation, transport between active and inactive regions; study of surface release processes; identification and characterization of the sources of exospheric constituents; detection and characterization of ionized species and their relation with the neutral atmosphere; space and time monitoring of exosphere/magnetosphere exchange and transport processes; study and quantification of escape, global scale source/sink balance and geochemical cycles synergistically with other experiments of BepiColombo (Mercury Sodium Atmospheric Spectral Imager (MSASI), Mercury Plasma Particle Experiment (MPPE) on Mercury Magnetospheric Orbiter (MMO); Mercury imaging X-ray spectrometer (MIXS), Search for exosphere refilling and emitted neutral abundance (SERENA) on Mercury Planetary Orbiter (MPO)). Two gratings and two detectors are used according to a specific, compact design. The spectrum detection is based on the photon counting method and is realized using micro-channel plate (MCP) detectors with Resistive Anode Encoder (RAE). Typical photocathodes are CsI or KBr for the extreme ultra-violet (EUV) range, CsTe for the far ultra-violet (FUV) range. Extra visible lines are monitored using a photo-multiplier (PM) that is also used in photon counting mode. In order to prevent sensitivity losses which are critical in UV ranges, a minimum of reflections is achieved inside the instrument using only an off-axis parabola and a set of holographic gratings. A one degree-of-freedom scanning system allows to probe, at the highest possible signal-to-noise ratio, selected regions and altitude ranges of interest. Different modes of observation will be used sequentially (vertical scans, along-orbit scans, grazing observations at twilight, etc.). During the mission, the instrument will be regularly calibrated on well chosen stars, in such a way to quantitatively estimate the overall degradation of the sensitivity of the instrument.