1. MIRI Observing Templates
MIRI is a NASA/JPL-led partnership with a European Consortium sponsored by ESA
NASA provides focal planes, signal chain
Consortium provides optical bench assembly
Science team
George Rieke (U of A, Lead)
Gillian Wright (ROE, Instrument PI and Co-lead)
Tom Greene (NASA-Ames)
Margaret Meixner (STScI)
Mike Ressler (NASA-JPL, Instrument Scientist)
Torsten Boeker (ESA-ESTEC)
Thomas Henning (MPIA)
Luis Colina (CSIC-IEM)
STScI Instrument team
Christine Chen (APT/ETC)
Scott Friedman (Commissioning)
Karl Gordon (Calibration)
Dean Hines (Operations)
Rachel Anderson
Misty Cracraft
8/1/10
C. H. Chen

2. MIRI Operating Configurations
Imaging
 = m wavelength range
Diffraction limited imaging with 0.11” pixels
~2 square arcmin field of view
Coronagraphy
Three 4 Quadrant Phase Masks (10.65, 11.4, and 15.5 m)
One Lyot Coronagraph (23 m)
Low Resolution Spectroscopy (LRS)
R ~ 100 from  = m
Medium Resolution Spectroscopy (MRS)
 = m wavelength range, goal to reach  = 28.3 m
Integral field spectroscopy with fields of view of 3” or more
R ~ from  = m
8/1/10
C. H. Chen

3. MIRI FOV on the Sky
For more information, see “Mid-infrared Instrument (MIRI) Operations Concept Document” Rev C edited by C. H. Chen JWST-STScI-00910
8/1/10
C. H. Chen

4. MIRI Data Format Nominal Data File Coordinates
(w/Ref Output)
Nominal Data File Coordinates
In Final Format
Reference Pixels - four pixels at the beginning and end of each row with no light sensitivity, one for each data output
Reference Output pixels - “blind” pixels interleaved with light-sensitive pixels that use a separate data output
8/1/10
C. H. Chen

5. MIRI Readout Patterns FASTMode SLOWMode
Each pixel in the (sub-)array is sampled once and that value is returned
Full frame time sec
Will be used to observe bright targets
SLOWMode
Each pixel in the (sub-)array is sampled 10 times, the middle 8 samples are averaged together and returned
Full frame time sec
Will be used to observe faint targets
8/1/10
C. H. Chen

6. Imaging Astronomical Observation Requests
Target acquisition
Current implementation does not include target acquisition for direct imaging
The smallest subarrays (SUB64 and SUB128) may require target acquisition
User will specify TA source coordinates, TA filter, and expected brightness for the TA source in TA filter
Filter
User will select based on the science justification
Subarray
User will select based on the science justification and the brightness of the target, with guidance from ETC/APT software
Readout Pattern
User will select based on the science justification and the brightness of the target with guidence from ETC/APT software
Dither Pattern
User will select based on science justification
8/1/10
C. H. Chen

7. Imaging: Filter Selection
8/1/10
C. H. Chen

8. Imaging: Subarray Selection
For more information, see “MIRI Subarrays for Planetary Transits and Other Bright Objects” Rev. A by C. H. Chen, G. H. Rieke, & K. D. Gordon, JWST-STScI
8/1/10
C. H. Chen

9. Imaging: Dither Pattern Selection
Available Patterns
No Dither (for transiting extra-solar planets)
5-Point Gaussian (SUB64, SUB128)
12-Point Reauleaux (SUB256, BRIGHTSKY, or FULL array)
311-Point Cycling Pattern (SUB256, BRIGHTSKY, or FULL array)
User specifies starting position in list of offsets and number of dither positions required
Available Pattern Sizes: S, M, L
Optimal pattern sizes exist based on the
For more information, see “MIRI Imaging Dither Patterns” Rev A by C. H Chen JWST-STScI
8/1/10
C. H. Chen

10. Coronagraphic Astronomical Observation Requests
Target acquisition
User will specify TA source coordinates, TA filter, and expected brightness for the TA source in TA filter
For more information, see “Mid-Infrared Instrument (MIRI) Target Acquisition Strategies and Use Cases” by Gordon & Meixner, 2008, JWST
Coronagraph/Filter
User will select based on the science justification
Subarray
Will be automatically selected based on Coronagraph/Filter selection
Readout Pattern
User will select based on the science justification and the brightness of the target with guidance from ETC/APT software
Dither Pattern
No dither pattern is allowed
8/1/10
C. H. Chen

11. Coronagraph: Coronagraph/Filter Selection
4QPM
Lyot
User must select which of the following coronagraphs they would like to use: 4QPM at 10.65, 11.4, or 15.5 m or Lyot Coronagraph at 23 m
8/1/10
C. H. Chen

12. LRS Astronomical Observation Requests
Target acquisition
User will specify TA source coordinates, TA filter, and expected brightness for the TA source in TA filter
For more information, see “Mid-Infrared Instrument (MIRI) Low Resolution Target Acquisition for Faint Sources” by Gordon, 2008, JWST-STScI
Filter
Is automatically set to “LRS Prism”
Subarray
User will select (either LRS-Slit or LRS-Slitless) based on the science justification and the brightness of the target, with guidance from ETC/APT software
Readout Pattern
User will select based on the science justification and the brightness of the target given guidance from ETC/APT software
Dither Pattern
If LRS-Slit, then user will select based on science justification
8/1/10
C. H. Chen

13. LRS Slit vs LRS Slitless Observations
Target placed in the slit
Target placed in the Lyot FOV
LRS Slit
LRS Slit Target Acquisition
FULL frame is readout
LRS Slitless
LRS Slitless Target Acquisition TBD
SLITLESSPRISM subarray is readout
8/1/10
C. H. Chen

14. LRS Slit Observations: Dither Pattern Selection
Point Source/Staring
Always two positions in the slit
Always 1/3 and 2/3 of the way along the slit
Extended Source/Mapping
Customizable grid of positions
User gives number of positions parallel and perpendicular to the slit
User gives offset between slit positions in direction parallel and perpendicular to the slit
For more information, see “The LRS Dither Pattern ” by C. H. Chen JWST-STScI
8/1/10
C. H. Chen

15. MRS Astronomical Observation Requests
Target acquisition
User will specify TA source coordinates, TA filter, and expected brightness for the TA source in TA filter
For more information, see “Mid-Infrared Instrument (MIRI) Target Acquisition Strategies and Use Cases” by Gordon & Meixner, 2008, JWST
Grating
User will select based on the science justification
Subarray
Only FULL array observations are allowed
Readout Pattern
User will select based on the science justification and the brightness of the target with guidance from ETC/APT software
Dither Pattern
User will select based on science justification
8/1/10
C. H. Chen

16. MRS Overview 10 arcseconds Wavelength/Velocity
Each channel’s field of view is
sliced, dispersed and detected.
Channel 1
( mm)
Channel 2
( mm)
Channel 3
( mm)
Channel 4
( mm)
8/1/10
C. H. Chen

17. MRS: Grating Selection
Select one sub-band at a time (A-”short”,B-”medium”, or C-”long”) or ALL
8/1/10
C. H. Chen

18. MRS: Dither Pattern Selection (TBD)
Pattern 1 - improved spatial sampling for all channels simultaneously
Pattern 2 - improved spatial and spectra sampling for one channel at a time (Ch 1, 2, 3, and 4 optimized patterns)
For more information, see “MIRI MRS Dither Patterns” by C. H. Chen & A. Glasse JWST-STScI
8/1/10
C. H. Chen