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Quanteye: Quantum Optics Instrumentation for Astronomy

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Quanteye: Quantum Optics Instrumentation for Astronomy OWL Instrument Concept Study QUANTUM OPTICS INSTRUMENTATION FOR ASTRONOMY 1 2 D. Dravins , C. Barbieri , 3 1 2 V. Da Deppo , D. Faria , S. Fornasier , 4 1 3 1 R. A. E. Fosbury , L. Lindegren , G. Naletto , R. Nilsson , 3 2 1 5 T. Occhipinti , F. Tamburini , H. Uthas , L. Zampieri (1) Lund Observatory, Box 43, SE-22100 Lund, Sweden (2) Department of Astronomy, University of Padova, Vicolo dell’Osservatorio 2, IT-35122 Padova, Italy (3) Dept. of Information Engineering, University of Padova, Via Gradenigo, 6/B, IT-35131 Padova, Italy (4) Space Telescope-European Coordinating Facility & European Southern Observatory, Karl-Schwarzschild-Straße 2, DE-85748 Garching bei München, Germany (5) INAF – Astronomical Observatory of Padova, Vicolo dell’Osservatorio 5, IT-35122 Padova, Italy OWL-CSR-ESO-00000-0162 — Version 1.0, October 2005 - 1 - Quantum Optics Instrumentation for Astronomy D. Dravins, C. Barbieri V. Da Deppo, D. Faria, S. Fornasier R. A. E. Fosbury, L. Lindegren, G. Naletto, R. Nilsson T. Occhipinti, F. Tamburini, H. Uthas, L. Zampieri OWL Instrument Concept Study, OWL-CSR-ESO-00000-0162 Version 1.0 — October 2005 - 2 - [ Blank page ] - 3 - TABLE OF CONTENTS ……………………………………………………………...… 3 Scope, Participants, and Schedule ………………………………………….....……...… 7 Executive Summary ………………………………………………...……………...……...… 9 1. The Road to Quantum Astronomy ………………………………………………...… 13 1.1. Introduction 1.2. Aims of the Study 1.3. High Time-Resolution Astrophysics 1.4. Which Timescales are Observationally Accessible? 1.5. Astrophysics on Subsecond Scales 1.6. Nanoseconds and Quantum Optics 1.7. Beyond Imaging, Photometry, and Spectroscopy 1.8. One-Photon Experiments 1.9. Two- and Multi-Photon Properties of Light 1.10. The Intensity Interferometer 1.10.1. The Narrabri interferometer 1.10.2. Intensity fluctuations when photon counting 1.10.3. The situation with a resolved star 1.10.4. Resolution vs. stellar surface temperature 1.10.5. The effect of atmospheric scintillation 1.10.6. The effect of polarization 1.11. Possible Modern Realizations of Intensity Interferometry 1.11.1. Very long baseline optical intensity interferometry? 1.11.2. Combining intensity interferometry with optical heterodyne 1.12. Intensity-Correlation Spectroscopy 1.13. Intensity Interferometry of Non-Photons 2. Quantum Phenomena in Astronomy ……………………………………………….. 43 2.1. Physics of Emission Processes 2.2. Cosmic Laser/Maser Sources 2.2.1. Non-equilibrium radiation in astrophysics 2.2.2. Mechanisms producing astrophysical lasers 2.2.3. A case study: Astrophysical lasers in Eta Carinae 2.2.4. Lasers in Wolf-Rayet and symbiotic stars 2.2.5. Hydrogen lasers/masers in the emission-line star MWC349A - 4 - 2.2.6. First masers in the Universe 2.2.7. CO2 lasers in planetary atmospheres 2.2.8. Lasers without population inversion? 2.2.9. Nanosecond pulses in pulsars 2.2.10. How short (and bright) pulses exist in nature? 2.2.11. Emission in magnetic fields of magnetars 2.2.12. Maser mechanism for optical pulsations in X-ray pulsars? 2.3. Photon Statistics as a Diagnostic Tool 2.3.1. Identifying laser effects in astronomical sources 2.3.2. Modeling photon statistics 2.4. Photon Orbital Angular Momentum 2.5. Quantum Gravity Effects? 3. Observational High-Speed Astrophysics ………………………………………….. 77 3.1. Examples of High-Speed Phenomena 3.1.1. Time domain and reprocessing: High-frequency phenomena in optical and infrared 3.1.2. Galactic X-ray binaries 3.1.3. Finding exoplanets through dark speckles 3.1.4. Occultations by the Moon, asteroids, and Kuiper-belt objects 3.2 Advantages of the Optical 3.3. Advantages of Great Light-Collecting Power 3.4. Advantages of Large Telescope Area 3.5. Using Optical Flux Collectors 3.5.1. MAGIC on La Palma 3.5.2. The H.E.S.S. observatory in Namibia 3.5.3. The Pierre Auger observatory in Argentina 3.5.4. Solar flux collectors 4. Instrumental Requirements ……………………………………………………….... 103 4.1. Optical and Near-IR Detectors for Nanosecond Astrophysics 4.1.1. Photomultipliers 4.1.2. Avalanche photodiodes 4.1.3. Futuristic detectors 4.2. Time Tagging and Time Distribution 5. QuantEYE Conceptual Instrument Design ………………………………...…… 127 5.1. QuantEYE Requirements and Identified Solutions 5.1.1. Time tagging accuracy and duration of operation 5.1.2 Spectral range and choice of detectors 5.1.3 Optical design requirements 5.1.4 Filters and polarizers 5.1.5 Electronic acquisition and data storage - 5 - 5.2. Requirements set by QuantEYE on OWL 5.3. Optical Design 5.3.1. Baseline: A non-imaging solution 5.4.1.1. Variants of the non-imaging solution 5.3.1.2. Further advantages of the non-imaging solution 5.3.2. An imaging solution 5.3.3. The second optical head 5.4. Photon Budget and Limiting Magnitude 5.4.1. Linear regime 5.4.2. Limiting magnitude 5.4.3. Integration times 5.5. Data Acquisition 5.5.1. Time-to-digital converter (TDC) 5.5.2. Clock reference and time precision 5.6. Electronics 5.6.1. Scenario (1): Ad hoc electronics 5.6.2. Scenario (2): Commercial solutions 5.7. Mechanical and Electrical Characteristics 5.8. Cost Estimates 5.9. Technical Issues in Current Design 5.10. Future Design Challenges 5.11. Instrumentation Physics 5.12. Quantum Information and Quantum Computing 5.13. A Possible Precursor for VLT 6. Observing with QuantEYE ………………………………………………………....... 169 6.1. Astronomical Targets 6.2. Connection to Other Astronomy Projects 7. Conclusions ………………………………………………………………………….…… 177 Appendices A1. Coherence Properties of Light …………………………………………………… 179 A1.1. Deviation from the Average, and Correlation Functions A1.2. Correlation Functions A1.3. Temporal Coherence and the Coherence Time A1.4. Spatial Coherence and the Coherence Area - 6 - A1.5. Coherence Volume and the Degeneracy Parameter A1.6. Bose-Einstein Statistics A1.7. Photon Antibunching and Sub-Poissonian Statistics A1.8. Photons from a Black Body A1.9. Fluctuations of Black-Body and Thermal Radiation A1.10. Statistical Analysis when Photon Counting A1.11. Experimental Evidence of Correlated Photon Fluctuations from Thermal Sources A2. Intensity Interferometry …………………………………………………………… 197 A2.1. The Original Interferometer at Narrabri A2.2. Examples of Intensity Fluctuations When Photon Counting A2.3. Resolution vs. Stellar Surface Temperature A3. High-Speed Instrumentation Worldwide ……………………………………… 205 A3.1. HSP on Hubble Space Telescope A3.2. HIPO on the SOFIA Airborne Telescope A3.3. ULTRACAM A3.4. STJ & TES: Superconducting Energy-Resolving Detectors A3.5. OPTIMA A3.6. MANIA A3.7. Optical SETI A3.8. Lunar- & Satellite Laser Ranging A3.9. QVANTOS A3.10. TRIFFID, MEKASPEK & MCCP, SUBARU, SALT, ESO-VLT, Opticon, and Other Acknowledgements ……………………………………………………………………..… 245 References and bibliography …...……………………………………………………… 247 - 7 - Scope, Participants, and Schedule Scope: This is the report of a conceptual design study of an instrument for optical astrophysics with the very highest time resolution feasible, adequate to identify and study also quantum-optical phenomena in the light from astronomical sources. It is not, however, any complete nor really comprehensive study of such an instrument, nor of all the science to be carried out with it. The limit of its scope should be understood from the fact that this document is the result of part-time work by a limited number of persons during a quite limited period of time, and thus parts of this report may more resemble “lecture notes” rather than an exhaustive monograph. Nevertheless, the combined documentation of various relevant issues, building upon previous varied experiences in observations, instrumentation, data analysis, and astrophysical theory, should give an adequate base upon which to build both a more detailed design study and the construction of a prototype instrument, to eventually evolve into a quantum eye for the future OWL telescope. Participants: The following persons took part in this study and in the preparation of this document: Cesare Barbieri, Department of Astronomy, University of Padova, Italy Vania Da Deppo, Department of Information Engineering, University of Padova Dainis Dravins, Lund Observatory, Lund University, Sweden Daniel Faria, Lund Observatory, Lund University, Sweden Sonia Fornasier, Department of Astronomy, University of Padova, Italy Bob Fosbury, ST-ECF, European Southern Observatory, Garching, Germany Lennart Lindegren, Lund Observatory, Lund University, Sweden Giampiero Naletto, Department of Information Engineering, University of Padova Ricky Nilsson, Lund Observatory, Lund University, Sweden Tommaso Occhipinti, Department of Information Engineering, University of Padova Fabrizio Tamburini, Department of Astronomy, University of Padova Helena Uthas, Lund Observatory, Lund University, Sweden Luca Zampieri, INAF, Astronomical Observatory of Padova, Italy Coordinator for this study at ESO: Bob Fosbury Coordinator for the OWL instrumentation studies at ESO: Sandro D'Odorico The working group held meetings: 11 November 2004, at ESO Garching 22-23 March 2005, at University of Padova 7-9 June 2005, at Lund Observatory 26-28 September 2005, at ESO Garching This document was finalized in October, 2005 Correspondence regarding this report should be directed to: Dainis Dravins, e-mail: [email protected] Cesare Barbieri, e-mail: [email protected] - 8 - [ Blank page ] - 9 - Executive Summary QuantEYE QuantEYE is conceived to be the highest time-resolution instrument in optical astronomy. It is designed to explore astrophysical variability on microsecond and nanosecond scales, reaching down to the quantum-optical limit.
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