Transcript Coronagraphic imaging

SCI (SPICA coronagraph
instrument)
Keigo Enya & SCI team
Outline

A mid-IR coronagraph instrument with both
imaging and low-resolution spectroscopic
capability at 3.5-27microns
 Scientific Objectives
- Targets& Required Specifications
 Concept Study, Current Status
 Resource Requirements
 Development and Test Plan
 Observing Program
Scientific Objectives/Targets
& Required Specifications
Scientific Targets

Direct Detection and Characterization
of Jovian Exoplanets by
- Coronagraphic imaging
- Coronagraphic spectroscopy
- Monitoring of planetary transit
Consistency with MRD

Description in MDR
Objective #1: Direct Detection and Characterization of
Exoplanets
To understand the diversity of the exo-planetary systems, we will
attempt direct detection and characterization of exoplanets in the
infrared wavelengths. Complement al two methods,
coronagraphic observation and planetary transit monitoring, are
described as key observations.

Therefore very consistent
Specification of Instrument
Parameter
Core wavelength (λ)
Observation mode
Specification
3.5−27 micron
w/wo Coronagraph, Imaging/
Spectroscopy
Coronagraphic mode
binary shaped pupil mask
Inner working angle (IWA) ~3.3×λ/D
Outer working angle (OWA) 16×λ/D
Throughput
~20%
Contrast
10-6 @PSF ( ~10-7 after subtraction)
Detector
1k×1k Si:As, InSb array
Field of View
~1’ x 1’
Spectral resolution
~20 and ~200
Filter
Band pass filters
Disperser for spectroscopy transmissive devices (e.g. grism)
in filter whele
Active optics
cryogenic DM and TTM
Concept Study
Current Status
Optics & Optical Elements (1)

Overview
Beamsplitter
Optics & Optical Elements (2)

Coronagraph mask (Binary shaped pupil mask)
 Laboratory demonstrated with visible light
Pupil mask
PSF
PSF (simulation)
Pupil shape
Non-corona
design
grahic direction
Discovery
angle
Coronagrahic
direction
Dark region
Optics & Optical Elements (3)

Active optics
- Deformable mirror
- Tip-tilt mirror

Other devices
- Mirrors (Collimetion/Focusing)
- Beamsplitter (Short/Long channel)
- Disperser (Grism, Prism, etc.)
- Science filters
Detectors

Commercailly available detectors will be used.
Detector
format
num. usage
InSb
1k x 1k (2k x 2k is OK) 1 science short channel
InSb
1k x 1k (2k x 2k is OK) 1 tip-tilt sensor
Si:As
1k x 1k (2k x 2k is OK) 1 science long channel
Volume & Structure

Volume & structure: see below
 Weight: 30 kg (including 20% margin)
Thermal Design
Cooled by only 4.5K stage
 Heat load: to be updated

- 16.36mW @the last report
- Design to reduce heat load is ongoing.
- Film Print Cable for DM control (parastic heat)
- New tip-tilt mirror design (heat generation)
Expected Performance
Parameter
Core wavelength (λ)
Observation mode
Specification
3.5−27 micron
w/wo Coronagraph, Imaging/
Spectroscopy
Coronagraphic mode
binary shaped pupil mask
Inner working angle (IWA) ~3.3×λ/D
Outer working angle (OWA) 16×λ/D
Throughput
~20%
Contrast
10-6 @PSF ( ~10-7 after subtraction)
Detector
1k×1k Si:As, InSb array
Field of View
~1’ x 1’
Spectral resolution
~20 and ~200
Filter
Band pass filters
Disperser for spectroscopy transmissive devices (e.g. grism)
in filter whele
Active optics
cryogenic DM and TTM
Resource Requirements
Field-of-View Requirement
Area: 1’ x 1’ (TBC)
 Location: center of FOV

Thermal & Cryogenic
Requirement
Cooled by only 4.5K stage
 Heat load: to be updated

- 16.36mW @the last report
- Design to reduce heat load is ongoing.
- Film Print Cable for DM control (parastic heat)
- New tip-tilt mirror design (heat generation)
Pointing / Attitude control
Requirement
Requirements
Pointing control
accuracy
Performance
0.03 [arcsec](3σ)
Pointing stability
0.03
[arcsec](0-P)/20min
Both pointing accuracy and stability are determined
By 1/10 x λ/D @ 5um
To be realized with a internal tip-tilt mirror
Structural Requirement

Volume & structure: see below
 Weight: 30 kg (including 20% margin)
Data Generation Rate & Data
Handling Requirement
TBD
 Roughly ~ half of 1 channel of MIRACLE

Warm Electronics

Function component
- Array driver
- Deformable mirror driver
- Tip-tilt mirror driver
- Mask changer
Weight: 25kg including 20% margin
 Volume: 400 x 500 x 200 [mm^3]

Operation & Observing
Mode

Coronagrahic
- Imaging
- Spectroscopy

Non-coronagraphic (including monitor obs.)
- Imaging
- Spectroscopy
Development and Test Plan
Key Technical Issues &
TRL

Cryogenic tip-tilt mirror
- Design and test are ongoing.

Cryogenic deformable mirror
- Demonstrated with a proto-device

Coronagraphic optics
- Demonstrated with visible light
Development Plan

Cryogenic tip-tilt mirror
- Design and test are ongoing.

Cryogenic deformable mirror
- Demonstrated with a proto-device (32ch@95K)
- Demo. of 1K ch. device @5K is in preparation.
- Development of film print cable in ongoing (to
reduce parasitic heat)

Coronagraphic optics
- High contrast demonstrated with visible light
- MIR demonstration in a cryo-chamber is in preparation.
Test & Verification Plan
TBD
 Roughly similar to MIRACLE + DM
operation + TTM operation

Development Cost
TBD
 Roughly (1 channel of MIRACLE) –
(detectors) + TTM + DM

Observing Program
Observation Plan to
perform Science Targets

Coronagraphic imaging
- the direct detection
- Coronagraphic spectroscopy

Non-coronagrapic monitor
- Planetary transit
Outline of Ground Data
Processing

Normal date reduction for MIR
observation.
Organization & Structure
for Development

Scientists and engineers in JAXA, community of
astronomy.
 Finding and Involving engineers in companies.

K. Enya, T. Kotan, T. Nakagawa, H. Kataza, T. Wada(ISAS/JAXA),
K. Haze (SOUKENDAI, ISAS/JAXA), S. Higuchi (Univ. of Tokyo, ISAS/JAXA),
T. Miyata, S. Sako, T. Nakamura (IoA/Univ. Tokyo), M. Tamura, J. Nishikawa,
T. Yamashita,N. Narita, H. Hayano (NAOJ), Y. Itoh (Kobe Univ.), T. Matsuo(JPL),
M. Fukagawa, H. Shibai (Osaka Univ.), M. Honda (Kanagawa Univ.),
N. Baba, N. Murakami(Hokkaido Univ.),
L. Abe (Nice Univ), O. Guyon (NAOJ/SUBARU)
T. Yamamuro (Optcraft), P. Bierden (BMC), SPICA coroangarph team

To be updated
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Summary

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We are developing SPICA Coronagraph Instrument
(SCI)
Main targets of SCI is detection and characterization
of exo-planets. It’s consistent with MDR.
Current design of SCI is presented.
R&Ds of key technology is successfully done or
ongoing including cryo-TTM and DM.
SCI team is consisting of many scientists and
engineers in JAXA, community of astronomy,
companies.