1. Introducing JWST’s NIRISS: The Near InfraRed Imager & Slitless Spectrograph TIPS/JIM 2011 September 15 Alex Fullerton STScI / HIA

2. TIPS/JIM 2011 September 15 The Tunable Filter Imager (TFI) TIPS / JIMPresenterTitle 2004 May 20Nelan JWST FGS SRR (April 7, 2004) 2005 March 17 Fullerton Overview of Calibration Activities for the JWST FGS-TFI 2005 May 19Fullerton FGS Tunable Filter Imager: Updates from PDR 2006 June 15Fullerton “Phase C” Design of the JWST/FGS Tunable Filter Imager 2008 Sept. 18Fullerton The Tunable Filter Imager Passes its CDR[s] 2010 Sept. 16Sivaramakrishnan The Non-Redundant Mask on JWST 2010 Nov. 18Sivaramakrishnan Non-Redundant Tilts (NRT): A Fallback Coarse Phasing Method for JWST Using TFI 2011 March 17Chayer JWST FGS & TFI Cryovac Risk Mitigation Tests

3. TIPS/JIM 2011 September 15 TFI Lessons Learned #1: Cryogenic etalons are tricky. July 20, 2011: Wave good-bye to TFI. Say hello to NIRISS. Near InfraRed Imager & Slitless Spectrograph

4. TIPS/JIM 2011 September 15 Design Considerations for NIRISS  Maintain capability to address core TFI Science “First Light” Exoplanets  Minimize technical risk Schedule is a (big) issue Cost is a (big) issue  Simplify operations Emphasis of nascent GTO Programs “Scope” is the only adjustable parameter available to CSA Program Management. Helps the S&OC (i.e., us) a bit.

5. TIPS/JIM 2011 September 15 Observing Modes TFINIRISS Narrow-Band Imaging R~100; tunable 1.5 – 2.6 & 3.0 – 5.0 microns Wide-Field Slitless Spectroscopy R~ 150; 1.0 – 2.5 microns Coronagraphic Imaging R~100; tunable 3.0 – 5.0 microns XXXXXXXXXXXXXXXXX Sparse-Aperture Interferometric Imaging R~100; tunable 3.0 – 5.0 microns Sparse-Aperture Interferometric Imaging Fixed medium-band filters Single-Object Slitless Spectroscopy R~700; 0.7 – 3.0 microns Broad-Band Imaging Fixed filters; 1 – 5 microns

6. TIPS/JIM 2011 September 15 Optical Layout of the TFI 2048  2048 HgCdTe 5.2 micron cut-off 18 micron pixels

7. TIPS/JIM 2011 September 15 Optical Layout of NIRISS 2048  2048 HgCdTe 5.2 micron cut-off 18 micron pixels

8. TIPS/JIM 2011 September 15 Elements in the NIRISS Dual Wheel

9. TIPS/JIM 2011 September 15 Wide-Field Slitless Spectroscopy

10. Slitless Spectroscopy with Two Orthogonal Grisms A spectrum for every source in the field of view.

11. NIRISS is Competitive With NIRSpec Bad Good

12. TIPS/JIM 2011 September 15 Sparse-Aperture Interferometric Imaging

13. Sparse-aperture interferometry with NIRISS pushes the angular resolution of JWST to its limit goal Beichman et al 2010 Bright planets Faint planets

14. Filter Set (3) for Use With MASKNR  Optimized for constraining temperature and mass.

15. TIPS/JIM 2011 September 15 Single-Object Slitless Spectroscopy

16. G700XD design  R ∼ 700 dispersion with grism along V2  Low dispersion with prism along V3, to separate orders  Weak cylindrical lens on front side of prism to induce a defocus along V3 weak cylindrical surface m=0 m=1 m=2 m=3 Slitless cross-dispersed 0.6-3.0 μm spectroscopy

17. 17 Schematic of Transit and Eclipse Science Measure size of planet 10 -2 See starlight transmitted through planet atmosphere 10 -4 Eclipse Planet thermal emission appears and disappears 10 -3 Learn about atmospheric circulation from thermal phase curves Transit Seager & Deming (2010, ARAA, 48, 631)

18. Transit Spectrum of Habitable “Ocean Planet” NIRISS G700XD perfectly suited for such challenging programs. The water vapor features below have a depth of 50 parts per million. 0.6 μm 2.5 μm NIRISS wavelength range

19. TIPS/JIM 2011 September 15 Broad-Band Imaging - Blue

20. TIPS/JIM 2011 September 15 Broad-Band Imaging - Red

21. NIRISS Sensitivity vs NIRCam Good In general, NIRISS is more sensitive than NIRCam. NIRISS with spare NIRCam filter filter

22. TIPS/JIM 2011 September 15 Summary NIRISS is coming! Capable instrument Complements & Extends near-IR capability of JWST Straightforward to operate* * Grisms / aperture mask introduce complexity on the “back end”. First Light: Lyman alpha emitters (10< z<13) ; photometric redshifts High-resolution imaging: exoplanet imaging and characterization Spectroscopy of transiting exoplanet atmospheres (including H 2 O, CO 2 features…)