MegaMIR – A Fizeau Mid-Infrared Camera for the LBT

1. MegaMIR – A Fizeau Mid-Infrared Camera for the LBT Erick Young – UAAmy Mainzer – JPLMike Werner – JPLPhil Hinz - UA

2. Mid-IR Context in the Next Decade • Spitzer will have completed it mission, leaving a rich legacy for follow up • GLIMPSE and MIPSGAL will have surveyed much of the Galactic Plane

3. GLIMPSE - Milky Way survey

4. Mid-IR Context in the Next Decade • Spitzer will have completed it mission, leaving a rich legacy for follow up • GLIMPSE and MIPSGAL will have surveyed much of the Galactic Plane • WISE will have completed its all sky survey at 3.5, 4.7, 12 & 23 m with 500 to 500,000 times better sensitivity than previous surveys • Note the talk by Mike Skrutskie on this morning • Limited angular resolution from a 40 cm telescope

5. WISE Mid-Infrared Survey WISE IRAS MSX

6. Mid-IR Context in the Next Decade • Spitzer will have completed it mission, leaving a rich legacy for follow up • GLIMPSE and MIPSGAL will have surveyed much of the Galactic Plane • WISE will have completed its all sky survey at 3.5, 4.7, 12 & 23 m with 500 to 500,000 times better sensitivity than previous surveys • Note the talk by Mike Skrutskie today • Limited angular resolution from a 40 cm telescope • JWST MIRI will be flying with supreme sensitivity and angular resolution set by ~ 6 m telescope • Ground-based cameras will be available on 8 – 10 m telescopes There will be a need to match the angular resolution available at shorter wavelengths through JWST and AO systems as well as at longer wavelengths that will be available through ALMA.

7. MegaMIR Fills in the Angular Resolution Gap

8. MegaMIR Fills in the Angular Resolution Gap

9. LBT Opportunity • There has been a convergence of technologies that will place the LBT in a position to have a unique capability for the next 10 – 15 years. • LBT with two co-mounted primary mirrors • LBT Interferometer • Note Phil Hinz’s talk Tuesday morning • Large format Mid-IR arrays suitable for high backgrounds • We are in a position to have the highest angular resolution wide-field thermal IR camera until the ELT era.

10. New Detector Technology • 10242 high background Si:As array designed by DRS in Cypress, CA . Development supported by JPL internal funds. • Design heritage: WISE (low background, 10242) and other high background chips using proven cryo-CMOS process, high-background Si:As detector material • HBR multiplexer Critical Design Review passed 5/19/06 • Bare multiplexers delivered to JPL 2/2008 • Detector wafers fabricated for this program in 2008 • Currently in process of hybridizing two arrays - first hybridizations had problems with unconnected indium bumps which will be fixed by changes to bumping process; root cause is known. • Multiplexer wafers have been probe-tested and run warm, verifying that clocking, biases, and windowing work properly • Cold testing will begin as soon as hybridization is complete • JPL has contracted to take delivery of 5 hybrids

11. MegaMIR Detector Characteristics • Detector Material: Si:As Impurity Band Conduction • Direct injection unit cells w/ 16 outputs. • Format: 1024 x 1024 , • 256 x 256 high speed window mode available • Buttable in 2 x 2 array • Frame Rate: 100 Hz • Dark Current: < 100 e- for T< 6 K • Switchable capacitance for two well depths: • 5 x 106 e- and 1x105 e- • Read Noise < 1000 e- , high well depth mode, 100 Hz frame rate.

12. PEC Tests Complete • Measurement of quantum efficiency made with Process Evaluation Chips (PEC) • Relative Spectral Response measured using FTIR Spectrometer • Spectral Response scaled to Quantum Yield (product of QE and internal gain) using measured broadband QE measurement • Illumination source • Blackbody source inside 4 K dewar shell and operated at 33.3 K • Resulting Quantum Yield vs wavelength agrees well with expectation from BIB model

13. Electronics Block Diagram Heavy use of commercial very high speed A/D, DSP, and network communications components.

14. Controller Electronics • JPL has built a custom set of control electronics to run the array • Flexible system that can read the entire array up to its maximum rate of 100 Hz (and also the 256x256 subarray mode at 16x higher frame rate) • Provide clocks and detector bias • Digitization, multiple sampling and coadding in real time prior to data storage on computer possible using 16 A/D converters and 16 DSP chips (one for each output) • Optical fiber system links DSP buffers to user computer • Fowler or sample-up-the-ramp sampling schemes will be possible

15. MegaMIR on the Large Binocular Telescope Interferometer (LBTI) • LBTI: Twin 8m telescopes separated by 22.8m, using a Universal Beam Combiner • MegaMIR on LBTI will achieve 0.10” spatial resolution @ 10 m • This is 3-4x higher spatial resolution than JWST

16. Universal Beam Combiner TO MEGAMIR

17. MegaMIR Imaging Channel Dichroic separates Mid-IR beam from NIR phase channel. Intermediate image allows incorporation of slit for GRISM. Lyot Stop in front of detector for detector for thermal background control. Plate scale: 0.03” / pixel

18. MegaMIR Phase Sensing Channel Corrects for piston between the two telescopes and provides tip-tilt correction for errors after A/O system Phase detector is a 2 mm array with a 22” FOV

19. MegaMIR PSF Calculations

20. MegaMIR Schematic Layout

21. MegaMIR on the UBC MegaMIR NOMIC

22. Wide Field + High Spatial Resolution • MegaMIR: Unique capabilities on the LBTI. • Imaging: 5 – 24 m • Field of view: 30 x 30 arcsec • Spatial resolution: 0.10 arcsec @ 10 m • Grism spectroscopy: R ~ 500 from 7 – 14 m • Detector: 1024 x 1024 pixel Si:As • Well depth: 5 x 106 or 9.6 x 104 electrons • Window mode: 256 x 256 pixel high speed subarray • Filters available: M; N; Qs; standard silicate set; • 20 m filter set; • possibly 7 – 14 m CVF • Sensitivity: 0.84 mJy 5-s 1 hour @ 10 m • 14 mJy 5-s 1 hour @ 20 m

23. MegaMIR Performance • MegaMIR will have sufficient sensitivity to follow up all of the GLIMPSE and most of the WISE mid-IR sources. • . Comparison of beam sizes and sensitivity for MegaMIR on Large Binocular Telescope Interferometer

24. Planetary Science with MegaMIR MegaMIR Slit • Time variability studies, hot & cold spots at poles, tropospheric waves, ring shadows, etc. • MegaMIR resolution on LBT will be betterthan Voyager IRIS, Galileo PPR, or Cassini CIRS AT the planet Mosaic of 35 Keck LWS images highlighting the first ever hot spot on a planet’s pole. (Orton and Yanamandra-Fisher 2005) Image from MIRLIN on IRTF (3x lower resolution) by Orton et al. 10”x10”LWS

25. ~30” ~30’ NGC 2264 Star Formation Region MegaMIR will be ideal for Spitzer follow-up IRAC and MIPS image of the star forming region NGC 2264 Blue = 4.5 m Green = 8.0 m Red = 24 m

26. IRAC and MIPS image of a star forming region Blue = 4.5 mm, Green = 8.0 mm Red = 24 mm ~30”

27. Near-IR image from Magellan - 0.30” resolution Blue = J, Green = H, Red = Ks MegaMIR can see dust-enshrouded objects that radiate primarily @ 10 m with luminosities < 1 L 0.1” Corresponds to the dust emission regions in the nearest star formation regions ~30”

28. Star Formation in External Galaxies • MegaMIR is sensitive enough to see individual PMS & evolved dusty AGB stars @ 1 Mpc @ 10 mm (e.g. M31) • Resolution sufficient to resolve extended star forming regions and individual star forming cores at the distance of M81. 0.10” ~ 2 pc Spitzer M81 image (Gordon et al 2004)3.6-4.5 (blue), 5.8-8.0 (green), 24 (red) microns

29. Conclusions • MegaMIR takes advantage of a unique capability of the LBT that will be unmatched for at least the next 10 – 15 years. • MegaMIR will enable unique high spatial and spectral resolution observations of targets found by Spitzer and eventually WISE. • MegaMIR will provide key follow-up of regions observed with JWST