Discovery Enabling UV Technologies Enabling Technologies for Next Generation Ultraviolet Astrophysics, Planetary, and Heliophysics Missions Study Start Date: 29 August 2011 Study End Date: 2 December 2011 Final Report Submission Date: 2 April 2012 Team Leads: Christopher Martin California Institute of Technology [email protected] Shouleh Nikzad Jet Propulsion Laboratory, California Institute of Technology [email protected] David Schiminovich Columbia University [email protected] 1 Discovery Enabling UV Technologies Table of Contents 1 Executive Summary ....................................................................................................................................... 3 2 What happened at the Workshops? ............................................................................................................... 5 3 Science Opportunities Enabled by New UV Technologies ............................................................................... 6 3.1 Mapping the flow of Baryons from the IGM to CGM to and from Galaxies ...................................................... 8 3.2 Following the cycles of star formation, chemical enrichment, feedback in and out of galaxies ....................... 11 3.3 Understanding the formation and evolution of stellar and protoplanetary and planetary systems; detection and characterization of exoplanets, and precision physical studies enabled by observations within our solar system. ..... 12 3.4 Opening discovery space .................................................................................................................................... 14 4 Discovery-Enabling New Detector Technologies ........................................................................................... 16 4.1 Introduction ........................................................................................................................................................ 16 4.2 Background: UV Detector Technology .............................................................................................................. 18 4.3 Vacuum Tube Photoelectric Detectors ............................................................................................................... 18 4.3.1 Generation-2 MCP Detectors: Borosilicate/ALD/GaN MCPs .................................................................. 19 4.3.2 Advanced Electron Bombardment Arrays .................................................................................................. 21 4.3.3 Cs free GaN photocathode ......................................................................................................................... 21 4.4 Solid-State Detectors .......................................................................................................................................... 22 4.4.1 Solid-State Wide Bandgap Detectors ......................................................................................................... 22 4.4.2 UV Single Photon Counting Silicon Detectors .......................................................................................... 24 4.5 Cryogenic Detectors ........................................................................................................................................... 29 4.6 Detectors for UV/Optical/NIR Observations ..................................................................................................... 30 4.6.1 Broadband Detectors using Silicon ........................................................................................................... 30 4.6.2 Broadband Detectors using substrate removed Mercury Cadmium Telluride .......................................... 30 4.7 Summary and Recommendations ....................................................................................................................... 30 5 Discovery-Enabling New Optical Component Technologies .......................................................................... 34 5.1 Broadband coatings: ........................................................................................................................................... 35 5.2 Bandpass/blocking filters ................................................................................................................................... 36 5.3 High performance diffraction gratings ............................................................................................................... 36 6 New Collaborations and Concepts Pursued .................................................................................................. 38 7 Conclusions and Recommendations ............................................................................................................. 38 7.1 Potential Impacts ................................................................................................................................................ 38 7.2 Recommendations/Conclusions ......................................................................................................................... 38 7.3 Study Evaluation ................................................................................................................................................ 39 7.4 Concluding remarks ........................................................................................................................................... 40 8 AcknowledGements ..................................................................................................................................... 40 9 Appendices .................................................................................................................................................. 41 9.1 Appendix I: References ...................................................................................................................................... 41 9.2 Appendix II: List of Participants ........................................................................................................................ 44 9.3 Appendix III: First Workshop Agenda ............................................................................................................... 45 9.4 Appendix IV: Merged Breakout Groups and Members ..................................................................................... 47 9.5 Appendix V: Professor Edoardo Charbon, DVS ................................................................................................ 48 9.6 Appendix VI: JPL-wide Seminar by Prof. Charbon. ......................................................................................... 49 9.7 Appendix VII: Public Lecture by Professor Eric Fossum .................................................................................. 51 9.8 Appendix VIII: Narratives on some of the promising technologies .................................................................. 52 2 Discovery Enabling UV Technologies 1 Executive Summary Our study sought to create a new paradigm in UV instrument design, detector technology, and optics that will form the technological foundation for a new generation of ultraviolet missions. This study brought together scientists and technologists representing the broad community of astrophysicists, planetary and heliophysics physicists, and technologists working in the UV. Next generation UV missions require major advances in UV instrument design, optics and detector technology. UV offers one of the few remaining areas of the electromagnetic spectrum where this is possible, by combining improvements in detector quantum efficiency (5-10x), optical coatings and higher-performance wide-field spectrometers (5-10x), and increasing multiplex advantage (100-1000x). At the same time, budgets for future missions are tightly constrained. Attention has begun to turn to small and moderate class missions to provide new observational capabilities on timescales that maintain scientific vitality. Developments in UV technology offer a comparatively unique opportunity to conceive of small (Explorer) and moderate (Probe, Discovery, New Millennium) class missions that offer breakthrough science. Figure 1. Explaining cosmogony. The next generation of missions will be design to explain the formation of structure and flow of baryons from the IGM to planets. UV measurements are critical for tracing the flow of gas (one of the principle root causes of structure formation) in the IGM, CGM, galaxies, and protoplanetary systems. Our study began with the science, reviewing the breakthrough science questions that compel the development of new observational capabilities in the next 10-20 years. We invented a framework for highlighting the objectives of UV measurement capabilities: following the history of baryons from the intergalactic medium to stars and planets. In astrophysics, next generation space UV missions will detect and map faint emission and tomographically map absorption from intergalactic medium baryons that delineate the structure of the Universe, map the circum-galactic medium that is the reservoir of galaxy-building gas, map the warm-hot ISM of our Galaxy, explore star-formation within the Local group and beyond, trace gas in proto-planetary disks and extended atmospheres of exoplanets, and record the transient UV universe. Solar system planetary atmospheric physics and chemistry, aurorae, surface composition and magnetospheric environments and interactions will be revealed using UV spectroscopy. UV spectroscopy