LAGRANGE REMOTE SENSING INSTRUMENTS: THE EXTREME ULTRAVIOLET IMAGER (EUVI)

C. Kintziger (CSL) - Presenter

S. Habraken (CSL)

P. Bouchez (CSL)

Matthew West (ROB)

David Berghmans (ROB)

Manfred Gyo (PMOD/WRC)

Margit Haberreiter (PMOD/WRC)

Jackie Davies (RAL Space)

Martin Caldwell (RAL Space)

Ian Tosh (RAL Space)

Stefan Kraft (ESA)

1 ESWW 2018, 9 Nov. 2018

LGRRS-EUVI | Mission overview

2 ESWW 2018, 9 Nov. 2018

See Poster 23 by J. Davies 4 remote-sensing instruments

LGRRS-EUVI | Mission overview

3 ESWW 2018, 9 Nov. 2018

5 in-situ instruments

LGRRS-EUVI | Mission overview

4 ESWW 2018, 9 Nov. 2018

• Overall Remote Sensing Instruments leader: RAL Space (UK)

• EUVI study led by three institutes:

– CSL (BE)

– ROB (BE)

– PMOD/WRC (CH)

• CSL activities

– EUVI Instrument manager:

• Overall management

• System study

• Optical engineering

• Thermal engineering

• AIT engineering

• Roles & Responsibilities

– BPI: Pr. Dr. Serge Habraken (CSL)

– Bco-I: Dr. Matthew J West (ROB)

– CSL work funded by Belspo via Prodex Programme

• ROB activities

– instrument requirements

– instrument operation

– ground segments

• PMOD activities

– electrical engineering

– mechanisms

– mechanical engineering

LGRRS-EUVI | Mission overview

5 ESWW 2018, 9 Nov. 2018

Parameter Requirement

Spectral resolution < 1.5 𝑛𝑚 𝐹𝑊𝐻𝑀

Spatial resolution < 5 𝑎𝑟𝑐𝑠𝑒𝑐

Field of view 42.6′ 𝑥 42.6′

Mass < 8 𝑘𝑔

Size < 600 𝑥 150 𝑥 150 𝑚𝑚

Power < 10 𝑊

• EUV Imager

– SSA programme (SWE)

– Location: L5

– Goal: image the full solar disc

– Waveband: EUV wavelength (e.g. 193 Å)

– Heritage: PROBA-2 SWAP

ESIO (GSTP)

Solar Orbiter EUI

LGRRS-EUVI | Instrument overview

6 ESWW 2018, 9 Nov. 2018

Semi-Static Structures Filaments/Prominences Active Regions Coronal Holes

Dynamic structures Flares Eruptions EUV Waves Dimmings

Regions Chromosphere Million Degree Corona

131 nm 19.5 nm 30.4 nm

• Selected wavelengths

LGRRS-EUVI | Instrument overview

7 ESWW 2018, 9 Nov. 2018

• Field of view

– Differs between selected wavebands

1. 195 Å

2. 131 + 304 Å

Toward Earth

62 arcmin

43 arcmin

43 arcmin

43 arcmin

LGRRS-EUVI | Instrument overview

8 ESWW 2018, 9 Nov. 2018

Channel 1

Channel 2

EUVI Optical Unit

Detector

Detector

PE

PE

Entrance f ilter

Entrance f ilterFEE DC/DC

Power

HK, data

Door

TC

EUVI Electronic Box

Filter wheel

Door

FPA camera

Mechanism

control

Optical sy stem

Optical sy stem

FPA camera

IPU

• Detector: EUI spare 3k by 3k, separate windowing options

1. 195 Å: 2300x1600, 1,6”/pixel, 3.2” spat. res. over 2 pixels

2. 131 + 304 Å: 2x2 binning, 800x800, 3.2”/pixel, 6.4” spat. res. over 2 pixels

• Cadence: Different for each spectral channel

1. 195 Å: 3 min

2. 131 Å: 2 min

3. 304 Å: 5 min

• Schematic configuration:

LGRRS-EUVI | Instrument overview

9 ESWW 2018, 9 Nov. 2018

• Obtained design

– ESIO-like truss structure

• Separate avionic box

• Lightweight and stiff

– SWAP-based optical design

• Improved spatial resolution and larger

FOV wrt SWAP (and ESIO)

• Similar baffling system

– Filter wheel

• Selects between 131 and 304 observation

– One-shot opening doors

LGRRS-EUVI | Performed analyses

10 ESWW 2018, 9 Nov. 2018

• Performed analyses

– Understanding of requirements

– Optical design

• Tolerancing

• Straylight

– Electrical design

– Instrument performance model

– Thermal analysis:

• Undergoing at CSL

– Structural analysis

• Undergoing at PMOD/WRC

EUVI Electronics

Electronic Box

IPCU

Optical Unit

Camera 1 SpW 2*(1)

SpW 2*(1)

Power 2*(1)

Heater EB 2*(1)

Filter Wheel Power

Power

Camera 2

EB HK Control

EB HK Control

EUVI-A CCSDS SpW 2*(1)

Thermistor EB 2*(1)

EUVI-B CCSDS SpW 2*(1)

EUVI SU 2*(1)

Radiator Thermal LinkHeater TL 2*(1)

Thermistor TL 2*(1)

Heater APS(A) 2*(1)

Thermistor APS(A) 2*(1)

Heater APS(B) 2*(1)

Thermistor APS(B) 2*(1)

EUVI Survival Heater RadiatorLink

EUVI Thermistor RadiatorLink

EUVI Operational Heater APS (A)

EUVI Thermistor APS (A)

EUVI Operational Heater APS (B)

EUVI Thermistor APS (B)

EUVI Survival Heater EB

EUVI Thermistor EB

LGRRS-EUVI | Performed analyses

• Encountered issues:

– Coating: dual-band coating for 131 + 304 Å is not “off-the-shelf” because those two

wavelengths do not fall within two successive Bragg orders (need to be factor ~2

between wavelengths)

• is feasible

• requires simulation and development

Other alternatives:

• Superpose 2 mono-band coatings on top of each other

• Implement a patterned coating on primary mirror

will lead to ~50% loss in efficiency BUT mono-band coating may be as

high as 2x more efficient than dual-band.

11 ESWW 2018, 9 Nov. 2018

LGRRS-EUVI | Way forward after PRR

12 ESWW 2018, 9 Nov. 2018

LGRRS-EUVI | Conclusion

13 ESWW 2018, 9 Nov. 2018