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All Hands Meeting. Important DARPA visit on March 27 th , 2008 Funding of four grants/contracts is at stake Our work part of DoD thrust in RBR/SoH Radiation Belt Remediation (RBR) Sleight of HAND (High Altitude Nuclear Detonation) Need to be aware of sensitivities of DARPA
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All Hands Meeting • Important DARPA visit on March 27th, 2008 • Funding of four grants/contracts is at stake • Our work part of DoD thrust in RBR/SoH • Radiation Belt Remediation (RBR) • Sleight of HAND (High Altitude Nuclear Detonation) • Need to be aware of sensitivities of DARPA • Presentations to emphasize technical content & the fit with End-to-End model • Our work is both basic & applied research • Presentations on the four grants (next page) • Numerical modeling capabilities • VPM?
Preliminary Agenda • Introduction to RBR (G. Ginet) • End-to-End Model (G. Ginet) • HAARP ELF/VLF Wave-injection • Marek, Morris, Mark, Max/Jeff (Buoys?) • TIPER • Kevin, Robert • DEMETER/Theory • Denys, Nikolai, Tim (Bell) • Siple Data Analysis • Andrew, Jeremie • Numerical Modeling Capabilities • Timothy, Praj • Proton Precipitation by LH waves (Bell) • VPM?
HAARP ELF/VLF Wave-injection Experiments: Rationale • SoH relies on cyclotron resonant scattering of killer electrons by ELF/VLF whistler-mode waves • Waves injected by transmitters or excited via chemical releases • Natural amplification can reduce requirements for SoH • Need to understand/quantify: ‘Learn to Amplify’ • Statistical quantification & physical understanding • Controlled wave-injection experiments well suited for such quantification due to known input signals • Magnetospheric amplification depends on geomagnetic conditions & on frequency-time format of injected signals • HAARP has location, agility, power, frequency-range for conduct of controlled ELF/VLF wave-injection experiments • Experiments have to be conducted over several years for statistical quantification and to determine operational utility of magnetospheric amplification
HAARP ELF/VLF Wave-injection Experiments: 2007 Results & Status • Alaska sites fully operational; on-line/chat room access • Buoys 1.5/2.0 deployed & used for two campaigns • Excellent initial data from Buoy 1.5; power problems thereafter • Impulsive noise in Buoy 2.0; cracked battery head suspected • Operated for 10 months; HAARP echoes visible between noise spikes • Currently no IRIDIUM contact from both Buoys • Several campaigns conducted with new-HAARP, with frequency/format controlled in real-time chat room discussions & data viewing • Several episodes of echoes & triggered emissions captured • Measurement of growth rate of ~15 dB/s on single pulses • Dependence on frequency & frequency-time signature • Rapid temporal variations (minutes) in growth rate • Entrainment from previous pulse causing rapid growth • Novel new method of ELF/VLF generation discovered • Geometric modulation increase ELF power by ~10 db for same HF power • Strong ELF signals observed at ~4500 km (Midway)
HAARP ELF/VLF Wave-injection Experiments: Milestones Already realized : • Observation of wave growth/triggering in conjugate region • Establishment of on-line operation of Alaska Sites • Detection of HAARP induced ELF at >4000 km distance Expected to be realized by September 2008: • Determine initial statistics of 1-hop & 2-hop occurrence • Data from 4 ship passages and eight Alaska sites • Several real-time campaigns in progress now • First assessments of HAARP-induced precipitation • Subionospheric VLF (TIPER-like measurement) • Optical signatures (with PIPER) • Quantify relationship of upward & downward excitation • Using data from Chistochina & DEMETER
HAARP ELF/VLF Wave-injection Experiments: Sep 2008-2011 • Quantify electrojet currents & ELF excitation mechanism • Needed before quantification of magnetospheric amplification • Systematic campaigns ‘Learn & Quantify Amplification’ • Dependence on frequency, frequency-time format, natural activity • Quantify growth rate & amplification for operational trade-offs • Determine geomagnetic conditions for maximum growth • Growth qualitatively different during very disturbed times? • Need to operate during rare solar disturbance events • Small/low-cost Buoys (deployed, picked-up by NSF ship) • Factor of 5 lower in cost, low risk, but captures most science • No IRIDIUM, data recorded in pre-designated minutes • Detection of precipitation by amplified HAARP signals • Quantify precipitation by amplified signals & triggered emissions • Complementary to TIPER, using non-amplified fixed frequencies • Low-ELF (~100 Hz) wave-injection experiments targeting proton-whistler growth & proton precipitation
Transmitter-Induced Precipitation of Electron Radiation (TIPER) Rationale: • Demonstrate & quantify key RBR/SoH concept • Use powerful VLF transmitter to precipitate electrons • Measure precipitation on DEMETER satellite • Measure precipitation via subionospheric VLF • Localized ionization enhancements persist for 10-100 s • Measure precipitation via optical signatures • Use novel photometric imaging array (PIPER) • Requires ON/OFF keying of operational USN assets • Detection realized by searching for the imposed ON/OFF pattern • Quantify relationship between injected VLF wave power density & precipitated electron flux • Important for both RBR/SoH and RRBR concepts • VLF network asset for future missions, SPIDER and DSX
TIPER Program: MilestonesRealized now versus by Sep 2008 • Conduct keying experiments with NPM (Hawaii) transmitter • Detection of NPM-induced precipitation on subionospheric paths • Many events detected; model-based quantification underway, but signatures are relatively weak, rendering quantification highly model-dependent • Detection of NPM-induced precipitation on DEMETER • Surprisingly few events • Precipitation induced by NWC (Australia) transmitter readily visible • Comparative theoretical analysis of other VLF transmitters • NWC (Australia) determined to be ~10 times better (in terms of location & power) • NAA (Maine) better located in terms of proximity to South Atlantic Anomaly • Trade & feasibility analysis of Airborne (TACAMO) transmitter experiments • Conduct keyed experiments with NAA (start 3/2008) and NWC (start 4/08) • Photometric Imager and VLF receivers already deployed in Atlantic sector • Several VLF Australian sites in place; key Amsterdam Island site in April 2008 • French island accessible by ship only; permission secured from French Antarctic Program • Photometric Imager to be deployed in Australia in March • DEMETER burst mode passes targeted for Atlantic & Australian passes • NPM keying experiments to be suspended by end of March • Next six months crucially important, in view of upcoming transmitter upgrades • Cannot key USN assets while other assets are upgraded
TIPER Program: Sep 2008-2012 3rd year of existing grant (9/08 to 9/09): • Conduct systematic tests with NAA & NWC • Optimize/cross-calibrate VLF/optical via comparison with DEMETER data • Conduct targeted tests with NPM during geomagnetic injection events • Conduct trial runs with TACAMO (Airborne VLF) New grant: Sep 2009-2012: • Regular observation of NWC-induced precipitation • Statistically quantify relationship of wave power density to electron flux • Cross-compare with NAA, NPM to assess longitude (drift loss cone) dependence • Start integrating results with end-to-end model; case study comparisons • Provide crucial ground-based support for DSX and SPIDER missions • Quantify transmitter-driven loss; use end-to-end model to determine lifetimes • Regular experiments with TACAMO; quantify role of transmitter location • Experiments with TARANIS (DEMETER replacement) with 10x better detector • Quantify role of geomagnetic/thunderstorm priming of drift-loss-cone edge • Complete integration of results with end-to-end model
DEMETER/THEORY Program: Rationale • Ground-based measurements only observe ‘ducted’ waves • Much of externally injected wave energy populating large radiation belt regions propagates in the ‘non-ducted’ mode • Satellite observations crucially complement HAARP wave-injection experiments • CNES mission DEMETER serendipitous gift to SoH/RBR program • Stanford cultivates >25 years collaboration with CNES/LCRE • Next CNES m-sat mission TARANIS even better (10x detector) • Stanford now has Co-I status providing wave analyzer FPGA • ELF/VLF generation via HF heating & coupling of waves upward & downward; highly nonlinear molecular physics, geophysics, and electromagnetic radiation/propagation/ scattering problem • Physics of ELF generation by ‘electrojet-antenna-in-sky’ not well known • Theoretical modeling is needed to optimize wave-injection experiments & to enable quantitative interpretation of results • Understand relationship of magnetospheric (upward) excitation versus excitation into the Earth-ionosphere waveguide (downward)
DEMETER/THEORY: MilestonesRealized now versus by Sep 2008 • DEMETER observations to determine HAARP-induced ELF illumination region • Detection of intense (>20 pT) column of upward radiation • Extremely surprising; verified with new full-wave model of HF-heated ELF radiation • Detection of 1-hop hybrid signals & triggered emissions in conjugate region • Detection of non-ducted 2-hop triggered emissions ~500 km east of HAARP • No evidence of any hops or triggered emissions at Alaska sites • Fully kinetic model of ELF/VLF modulated HF heating • Full-wave model of ELF/VLF radiation from HF-heated ionospheric currents • Intense column of upward excitation, consistent with DEMETER observations • Fully accounts for Earth-ionosphere waveguide coupling & resonance effects • Allows calculation of fields on the ground & at DEMETER (700-km altitude) • Complete calculations of HAARP-induced current and charge distributions • Quantify effects of HF frequency on ELF amplitude (ground- & DEMETER) • Direct comparison of fields predicted at 700-km with DEMETER • Use ionospheric profile and magnetometer measurements as input • Quantify electrostatic wave generation at low altitudes using measurements keyed NPM pulses (and sidebands) on DEMETER • Initiate development of Stanford FPGA for TARANIS (DEMETER follow-up)
DEMETER/TARANIS/THEORY Program: Sep 2008-2011 • Determine HAARP-induced illumination region(s) in both hemispheres • Statistically significant number of passes • Measure signal intensity, k-vector and Poynting flux • Quantify relationship between upward versus downward radiation • Comparative analysis of DEMETER and ground-based data • To what degree is data from Alaska representative of magnetospheric excitation? • Quantify trans-ionospheric propagation of VLF signals (e.g., NPM pulses) • Use DEMETER measurements of wave pulses, sidebands, and irregularities • Combine with predictions of full-wave model • Extend kinetic HAARP heating model to 2D/3D • Quantify ELF generation via geometric modulation • Extend full-wave model of ELF/VLF radiation from ionospheric currents • Include Earth curvature and lateral gradients (currently horizontally stratified) • Include segmentation to allow propagation in e-i waveguide (up to Midway distances) • Quantify effects of HF beam defocusing • Extend HF-heating model to low-ELF and ULF generation • Complete Stanford FPGA (automatic wave analyzer) for TARANIS • Quantify effects of irregularities (natural & artificial) on ELF generation • Start TARANIS observations (depending on launch date --- 2010?)
Siple Data Analysis Program: Rationale • SoH relies on cyclotron resonant scattering of killer electrons by ELF/VLF whistler-mode waves • Waves injected by transmitters or excited via chemical releases • Natural amplification can reduce requirements for SoH • Need to understand/quantify: ‘Learn to Amplify’ • Statistical quantification & physical understanding • Controlled wave-injection experiments well suited for such quantification due to known input signals • Magnetospheric amplification depends on geomagnetic conditions & on frequency-time format of injected signals • Excellent data available from ~15 years of Stanford experiments at Siple Station, Antarctica • Cost-effective means of quantification/assessment of the operational reliance on magnetospheric growth
Siple Data Analysis Program: Milestones Realized (Mar 08) • Restored/developed apparatus to reduce all VLF data associated with Siple transmitter experiments, including: • Data from ground-based sites in Quebec • Data from receivers on Dynamics Explorer-1 and ISEE-1 missions • All ground data from 1983, 1986, 1987 and 1988 digitized • Only 5% of data lost due to age of storage media • Most data remains high-quality & intact • First statistical studies initiated with 1986 data • Maximum of activity near dawn • Role of ionospheric absorption identified • Preliminary statistics for 1-hop versus 2-hop & growth rate • New understanding of amplification & saturation • Rapid nonlinear growth starts at particle trapping levels and saturates upon destruction of anisotropy by amplified waves • Associated with large electron fluxes near the equator
Siple Data Analysis Program: April 2008-2011 • Complete new model of physics of growth & saturation • Digitize remaining data on analog tapes • 1973-82 data from Quebec • Satellite (DE-1, ISEE-1) data from 1978-88 • Develop automated timing identification & statistical mining algorithms • Conduct statistical studies to quantify • Threshold amplitude, growth rate, amplitude at saturation • Dependence on frequency, frequency-time format • Dependence on geomagnetic & solar activity • Use models to correlate characteristics of amplification with available particle data (e.g., CRESS, POLAR satellites) • Determine correlation between predicted & observed growth • Determine predictability of growth based on particle data • Develop metrics to quantify presence of natural activity • Relate metrics to likelihood & characteristics of growth using statistical data base