Current Status of SPICAFocal Plane Instruments

October 19, 2009

Hideo Matsuhara (ISAS/JAXA) & FPI team

MIRACLE (Mid-InfRAred Camera w/o LEns)

MIRACLE is a mid-IR instrument with imaging and low-resolution spectroscopy consisting of two channels:

• Filter-wheel : imaging band (R~5) & spectroscopy with grism/prism (R~100)

2K x 2K

MIRACLE Optics

Telescope Focus

Fore-optics

collimator

Fore-optics camera

Re-imaging focus

Final image

Rear-optics

collimator

Rear-optics camera

MIRMES (MIR Medium-Resolution Spectrometer)

Wavelengths: 16-38mm, 2 channels (Si:As x 1, Si:Sb x 1) Image slicer, Spectral resolution 　 700-1000

ARM-S ARM-L

Wavelength coverage 10.32 mm - 19.35mm 19.22 mm - 36.04mm

Spectral resolution (R=l/ )Dl ~1500 ~900

pixel scale 0.37” 0.72”

slit width 1.11” (3 pixel) 3.6” (5 pixel)

FOV size 12.95” x 5.55” 25.2” x 18.0”

(35pixel x 3 pixel x 5rows)

(35pixel x 5 pixel x 5rows)

MIRHES (MIR High-Resolution Spectrometer)

Short(S)-mode Long(L)-mode

Wavelength coverage 4 – 8mm 12 – 18mm

Spectral resolution (R=l/ )Dl

30,000 20,000 – 30,000

Slit width 0.72” 1.20”

Slit length 3.5” 6.0”

Dispersion element

ZeSe immersion grating

KRS5 immersion

grating

Cross disperser Reflective reflective

MIRHESS-mode

MIRACLE/MIRMES/MIRHES: Current Progress

MIRACLE Optics design mostly fixed: Short-wave ch. Detector format is now 2K x 2K (Raytheon IBC) Mid-IR filter (long-wave ch.) development is underway SHI will design :

Structure Moving mechanism (Filter Wheel, slit changer)

Pointing control : Slit-mapping is under consideration, which will relax the absolute

pointing requirement

MIRMES Spectrometer concept has been fixed, Optical design underway Beam splitter is a key issue

MIRHES R&D of Immersing grating for long-wave ch.

SCI : SPICA Coronagraph Insturment

A mid-IR coronagraph instrument with both imaging & low-res. spectroscopic capability.

Major goal : direct imaging & spectroscopy at 3.5-27mm

Coronagraph method Binary-shaped pupil mask (baseline) Contrast > 10-6

Field of View: 1.0 x 1.0 arcmin2

Spectral resolution : 20-200

Current status : Draft optical, structure design finished improved Tip-tilt design

SAFARI SPICA Far-infrared

Instrument

Leaded by SAFARI consortium in Europe Imaging Fourier-transform spectrometer

covering 35-210mm FOV : 2 x 2 arcmin2

Wavelength resolution 2000 at 100 mm is maximum

SAFARI Design @Phase-A1 conclusion

Current cold mass : 38.8kg (22% margin to 50kg allocation)

BLISS (Background-Limited Infrared-Submm Spectrograph) 　

Proposed by US AO for conceptual study released by NASA

(due 2nd Nov.) Wavelength: 38-430 mm, Spectral resolution R=700 Grating spectrometer, 5 channel, 4200

bolometers at 50mK

FPC (Focal-Plane Finding Camera)

Korean-leading instrument, with participation of NAOJ FPC-G : guidance sensor for the Attitude control System

to stabilize the attitude with an accuracy of 0.05” FPC-S: science camera for 2.5-5 mm imaging

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Cold stage heat generation

Assumption: Baseline : No parallel mode Any observations will be executed by using single

FPI, excluding FPC-GCurrent Status

<15mW ＠ 4.5K for any observation modeExceeds 5mW@1.7K (baseline allocation

for 1.7K stage) but less than 10mW

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Heat load (max/average) @4.5K stage (09/08/31) Ｔ

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Heat load (max/average) @1.7K stage (09/08/31)

FPI Mass (@ESA CV)

FPIWeight

(kg)comment

MIRACLE

60.0

with 20% margin

MIRMES

MIRHES

SCI 30.0 FPC 10.0 SAFARI 50.0 BLISS 30.0 (optional FPI)IOB, FPI cover 50.0 with 20% marginTotal 200 excluding BLISS

FOV allocation

Pick Off Mirrors

FPI footprint on IOB

Folding Mirror Module

If the pick-off mirror for each FPI belongs to the cold hardware volume of the FPI, assembling of the whole FPIs on IOB is really difficult

We decide to consider a common pick-off module (PoM) separated from each FPI, but mechanically I/F to IOB PoM is a subsystem of IOBA

There may need a hole in the center of PoM, for the optical test of STA? May be an issue for SCI’s pick-off location

Important alignment issue for MIRACLE,MIRHES, SCI They request “co-focus” : stringent accuracy requirements in

their back-focus location How can we achieve this?

ICS-FPI

ICS (interface control specification) document should be prepared for SRR I/F with STA (mechanical/optical), CRYO (thermal), BM (bus module:

electrical), AOCS (pointing control I/F) MIRACLE, MIRMES, MIRHES & SCI will be put in ICS-FPI Dedicated ICS for SAFARI, BLISS, FPC

Following issues should be prepared by 5th Nov. (or so) Operation mode Observing mode Warm electronics power/heat in each operating mode

(observation/standby) ``Urgently” required info.:

Cold Weight, Volume, outer shape … necessary for the design of whole FPI assembly

FPI SELECTION PROCESS

Japanese-lead instruments

MIRACLE Instrument Proposal / Concept study report will be released

by Jan. 2010 (may be delayed) Refereeing / Reviewing in Jan-March 2010 (may be

delayed) by a Japanese Selection committee Decision of the Selection will be authorized by JAXA

MIRMES, MIRHES, SCI Instrument Proposal / Concept study report will be released

by Apr. 2010 Refereeing / Reviewing in Apr-July 2010 by a Japanese

Selection committee Decision of the Selection will be authorized by JAXA

Oversea-based instruments

SAFARI Leaded by European SAFARI consortium Result of Concept study will be reviewed by ESA Also JAXA’s review expected before SDR

BLISS Leaded by US under NASA AO Participation critically depends on the Decadal Survey report Selection will be decided by discussion between JAXA and

NASA FPC

Leaded by Korean consortium (w/ participation of NAOJ) FPC-G (mandatory) , FPC-S (optional) Review & selection of the specifications will be decided by

discussion between JAXA and Korean consortium