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MURI KICK-OFF MEETING June 5, 2007 PARTICIPATING UNIVERSITIES UNIVERSITY OF MARYLAND, COLLEGE PARK STANFORD UNIVERSITY UNIVERSITY OF CALIFORNIA, LOS ANGELES.

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Presentation on theme: "MURI KICK-OFF MEETING June 5, 2007 PARTICIPATING UNIVERSITIES UNIVERSITY OF MARYLAND, COLLEGE PARK STANFORD UNIVERSITY UNIVERSITY OF CALIFORNIA, LOS ANGELES."— Presentation transcript:

1 MURI KICK-OFF MEETING June 5, 2007 PARTICIPATING UNIVERSITIES UNIVERSITY OF MARYLAND, COLLEGE PARK STANFORD UNIVERSITY UNIVERSITY OF CALIFORNIA, LOS ANGELES DARTMOUTH COLLEGE VIRGINIA TECH BOSTON COLLEGE

2 OUTLINE Radiation Belts (RB) –Topology - Fundamentals RB Remediation (RBR) Why? MURI – Overarching Objectives MURI – Methodology, Governance, Transition MURI – Resources The Physics of Loss Rate Physics and Technology Challenges –Radiate, Amplify, Propagate, Precipitate VLF Radiation from Space Transmitters Novel ULF/VLF Radiation Concepts –ULF Injection Using Neutral Gas Releases at Orbital Speed –Rotating Magnetic Fields (RMF) Amplification – Artificially Stimulated Emissions Propagation – Natural and Artificial Ducts Cyclotron Masers – Resonators and Guides – Ion Precipitation ULF Injection in Space Stimulated ULF Triggering and Ion Precipitation

3 RADIATION BELTS – TOPOLOGY e - /cm 2 /sec, >1 MeV >10 6 >10 5 10 4 L = 2 L = 3 L = 7 Inner RB 1.5 3 Lifetime and functionality of satellites ~ Energetic particle dose Plasmapause (L~4) appears to mark transition from high to low flux of energetic particles

4 RB – PHYSICS ISSUES Energetic particle flux as a function of L controlled by 1.Particle Injection 2.Radial Transport 3.Energization 4.Particle Loss 1 2,3 4 in out in=out Leaky Bucket Model

5 RB REMEDIATION (RBR) 1 2,3 4 Sudden natural or artificial injection of relativistic electrons in the inner magnetosphere (e.g. by accidental or deliberate High Altitude Nuclear Detonation -HAND ) in out in=out Inject a bucket of water Time to return to equilibrium depends on the size of the hole >10 8 10 6 10 5 10 4 T eq >2 yr

6 THE HALLOWEEN STORM FROM 1-10 NOVEMBER, 2003 OUTER BELT CENTERED NEAR L  2.5 AND PLASMASPHERE WAS DISPLACED INWARDS LEADING IN NEW RADIATION BELT POPULATION IN THE SLOT AND INNER BELT. DECAY RATES DEPENDED HIGHLY ON L VALUE AND VARIED FROM 35 DAYS TO MORE THAN A YEAR BAKER AND KANEKAL 2007

7 OVERARCHING OBJECTIVES DEVELOP QUANTITATIVE DATA DRIVEN MODELS OF THE LOSS RATE OF ENERGETIC PARTICLES IN THE INNER MAGNETOSPHERE AND TEST AGAINST OBSERVATIONS PROVIDE THE PHYSICS UNDERPINNINGS THAT CAN LEAD TO PRACTICAL SPACE OR GROUND BASED SYSTEMS THAT CAN ARTIFICIALLY CONTROL THE ENERGETIC PARTICLE LOSS RATE DEVELOP THE SCIENTIFIC AND ENGINEERING MANPOWER WITH THE INTERDISCIPLINARY SKILLS REQUIRED TO ADDRESS FUTURE MAJOR TECHNICAL ISSUES OF NATIONAL SIGNIFICANCE

8 METHODOLOGY - GOVERNANCE TOPICS ADDRESSED BY AN INTERPLAY OF THEORY/COMPUTATION, LABORATORY EXPERIMENTS, FIELD EXPERIMENTS, SATELLITE MEASUREMENTS AND DATA ANALYSIS CONSORTIUM WILL OPERATE AS A COHERENT ENTITY WITH PARTICIPATING UNIVERSITIES AND ASSOCIATED GOVERNMENT LABORATORIES AND INDUSTRY PROVIDING COMPLEMENTARY EXPERTISE AND NOT AS A SERIES OF INDPENDENT PROJECTS CONTINUOUS INTERACTION AND QUICK TRANSITION OF RESULTS TO RELEVANT DoD LABORATORIES (AFOSR, NRL) OVERALL CONSORTIUM COORDINATION BY PAPADOPOULOS AND INAN WITH ADVICE FROM SENIOR MEMBERS – SAGDEEV, MORALES, LIU, MAGGS, MISHIN,FUNG,… THE FORMATION OF AN EXTERNAL SCIENCE ADVISORY COMMITTEE WITH MEMBERS SUCH AS KENNEL, COFFEY, WALT, LANZEROTTI HAS BEEN RAISED WITH THE PM BUT NOT YET RESOLVED

9 RESOURCES HAARP DEMETER DMSP CONJUGATE BUOYS LAPD WIDE RANGE OF CODES THAT COUPLE TO THE ABOVE EXPERIMENTS

10 PHYSICS OF LOSS RATE V || VV SCATTERING RATE DEPENDS ON 1.AMPLITUDE OF RESONANT WAVES 2.PRESENCE OF LARGE B GRADIENTS 3.PATCHES OF LARGE AMPLITUDE NON-RESONANT ES OR EM WAVES B0B0 trapped  REQUIRES LARGE MAGNETIC WAVE ENERGY IN THE PROPER WAVELENGTH RANGE (~1-3 KM) TO BE INJECTED AND GUIDED IN THE PUMPED BELT REGION

11 PHYSICS AND TECHNOLOGY CHALLENGES WAVE INJECTION: VLF INJECTION FROM SPACE BASED ANTENNAS VLF INJECTION FROM GROUND TRANSMITTERS ULF INJECTION FROM SPACE – NEUTRAL GAS INJECTION INNOVATIVE INJECTION CONCEPTS - ROTATING MAGNETS GLOBAL WAVE AMPLIFICATION VLF AMPLIFICATION – ARTIFICIALLY STIMULATED EMISSIONS STIMULATED ULF EMISSIONS – PROTON PRECIPITATION GLOBAL WAVE PROPAGATION VLF DUCTED AND NON-DUCTED PROPAGATION ULF WAVE PROPAGATION PHYSICS OF PRECIPITATION WEAK VS. STRONG DIFFUSION RELIABLE MODELING TESTED AGAINST AVAILABLE DATA (GROUND TRUTH)

12 EFFICIENCY OF VLF RADIATION FROM SPACE-BASED TRANSMITTERS USE LAB EXPERIMENTS IN LAPD CHAMBER TO VALIDATE PERFORMANCE CODES FOR ELECTRIC AND MAGNETIC DIPOLES WHAT PHYSICAL PROCESSES CONTROL THE EFFICIENCY AND FAR FIELD COUPLING OF HIGH POWER, LOW FREQUENCY ANTENNAE IN A LOW DENSITY PLASMA. ELECTRIC VS MAGNETIC DIPOLES. STANFORD ANTENNA IN PLASMA AND OTHER THEORETICAL AND EMPIRICAL MODELS (SAIC, UMass) HAVE BEEN USED TO DESIGN DSX EXPERIMENT INPUT IMPEDANCE FUNCTION OF SHEATH. REQUIRES DYNAMIC TUNING NEED FOR CODE VALIDATION

13 NOVEL WAVE INJECTION CONCEPTS NEUTRAL GAS INJECTION Step 1. Step 2. USE ENERGY (30 GJ/Ton) STORED IN RELEASING A LARGE AMOUNT OF LOW IONIZATION POTENTIAL GAS (e.g. Li) AT ORBITAL VELOCITY TO GENERATE THE RESONANT WAVES – GANGULI ET AL (2007) PHYSICS CHALLENGES RELEASE PHOTO IONIZA TION CONVERSION EFICIENCY FROM FREE ENERGY TO RESONANT SPECTRAL ENERGY SATURATION LEVEL OF PRIMARY ALFVEN ION CYCLOTRON INSTABILITY – VT WAVE CASCADE IN k-SPACE TRANSFERS ENERGY TO RESONANT REGION – UMCP INJECTION REQUIREMENTS FOR STRONG SCATTERING – UMCP TRAPPING OF WAVES IN MULTI-IONIC BUCHSBAUM RESONANCES - DC EFFORT MAINLY THEORETICAL FEEDS DIRECTLY TO NRL – POSSIBLE CHAMBER EXPS IN OPTION PHASE

14 NOVEL WAVE INJECTION CONCEPTS ROTATING MAGNETIC FIELDS How are currents generated and maintained ? Novel Antenna Concepts RMF GENERATED EITHER BY ROTATING A PERMANENT OR SUPERCONDUCTING MAGNET OR BY PHASED ANTENNAS 0 17.2 c/  pe PHYSICS OF INTERACTION OF A RMF WITH MAGNETOPLASMA NOT UNDERSTOOD 3-D EMHD MODELING AT UMCP PARALLEL LAB EXPS AT LAPD - GEKELMAN

15 B- FIELD GRADIENTS DRIVEN BY RFM DIFFERENTIAL MOTION OF ELECTRONS AND IONS GENERATES PLASMA CURRENTS RESULTING IN INDUCED FIELD DECAYING AS 1/r n WITH n<<3 LARGE QUASI- STATIC B- FIELD GRADIENTS CAN BREAK THE ADIABATIC INVARIANCE OF ELECTRONS AND SCATTER THEM INTO THE LOSS CONE CARTOON OF CONCEPT Primary field (blue lines) Electron motion (red dots) Secondary field (red lines) Courtesy R. Winglee OPTION PHASE – ASSESS INDIVIDUAL PLATFORM PROTECTION

16 Artificially Stimulated Emissions AMPLIFICATION Artificially Stimulated Emissions (ASE) COHERENT GROWTH 20-30 dB THRESHOLD SIGNAL SATURATION PHASE ADVANCE PRIOR TO TRIGGERING TRIGGERED EMISSIONS – risers, fallers, hooks ENTRAINMENT GROWTH SUPPRESSION for 2 signals with  f< 30 IMPORTANCE OF CHIRPING Probably the most serious challenge to our current understanding of nonlinear plasma physics 20-30 dB amplification major leverage to RBR Helliwell Stanford Siple exps

17 ASE - ISSUES Physics of coherent amplification and saturation Role of chirping and optimization Role of ducts Physics and control of threshold – inhomogeneity, F(v),else ? Reason for frequency shift – inhomogeneity or nonlinearity? Is threshold related to oscillator behavior (BWO) Is amplification affected by relativistic effects or a nuclear environment? APPROACH 1.Specialized codes and parallel architectures; UMCP + NRL, DC 2.Targeted field experiments – HAARP, Alpha transmitter; Inan 3.Targeted Lab experiments – TBD (Need ECRH source) UCLA

18 VLF PROPAGATION - DUCTS  The perturbed plasmasphere contains field-aligned density irregularities that efficiently guide whistler waves CRRES orbit 766 In addition to loss-cone distribution amplification requires the presence of ducts (field-aligned irregularities with  n/n>.01) 1. Model ducted propagation in inhomogeneous media and test against lab experiments (DC – Streltsov, UCLA Gekelman) 2.Understand and predict time and location of natural ducts (BC – Mishin) 3.Model and conduct field tests of artificial duct formation using F- region heating with HAARP (UMCP)

19 Plasmaspheric Duct Formation 1.Analyze magnetically-conjugate observations from the Cluster and DMSP satellites to find the response time of the plasmasphere to sub-storms. 2.Analyze available satellite (CRRES/Cluster/IMAGE/DMSP) data to find the drivers of plasmaspheric field-aligned irregularities (FAI) and their spatial/temporal characteristics. 3.Conduct theoretical and numerical studies of the (sub) storm-time ring current- plasmasphere interaction resulting in the FAI (ducts) generation. 4.Analyze observations from Siple and HAARP to determine geophysical conditions necessary and sufficient for the formation of ducts. 5. Develop algorithms that allow location and time of duct formation

20 ARTIFICIAL TRANSIONOSPHERIC DUCTS 2D MODELING SHOWS THAT TRANSIONOSPHERIC DUCTS WITH  n/n>.5 FORM IN 15 MINUTES WITH FULL HAARP F-REGION HEATING CONDUCT 3D SIMULATIONS - UMCP CONDUCT HAARP EXPS DIAGNOSED WITH OVERFLYING SATS (DMSP, DEMETER) AND STANFORD VLF RECEIVERS – UMCP DETERMINE RELEVANCE OF LAB EXPERIMENT

21 Temporal Evolution of Density

22 CYCLOTRON MASERS - RESONATORS AND GUIDES – ION PRECIPITATION Ion Cyclotron Instability SHEAR ALFVEN WAVE B Fabry-Perot like Resonator Cash et al. 2006

23 MASER ELEMENTS - FEEDBACK CONTROL OF CYCLOTRON MASERS BY IONOSPHERIC HEATING TRIGGERING STMULATED ULF WAVES AND ION PRECIPITATION INJECTING ULF POWER IN THE MAGNETOSPHERE INVERTED POPULATION LOSS-CONE

24 IONOSPHERIC ULF GENERATION F-PEAK REFLECTION B D/E Region heating+ Electrojet 1. SAW – REQUIRES EJet AND D/E REGION X-MODE HEATING – OBSERVED ONLY IN NEAR ZONE, ALONG THE FLUX TUBEAND POSSIBLY CONJUGATE Shear Alfven wave BoBo v1v1 E1E1 SAT 10 pT BAE BAE-UMCP

25 IONOSPHERIC ULF GENERATION 2. MSONIC WAVE – REQUIRES F-REGION O-MODE, UPPER HYBRID HEATING; INDEPENDENT OF EJet – WEAK OR NO NEAR FIELD UH heating k E1E1 BoBo Magnetosonic Alfven Wave (compressional) Bill Bristow UAL

26 ULF POWER INJECTION IN THE MAGNETOSPHERE BAE-UMCP-STANFORD COLLABORATION 1OO nT ULF MODULATION O-MODE.1 Hz BETWEEN 6:47.30 AND 6:59.30. DEMETER FLYOVER DETECTED.1 Hz ACTIVITY IN THE ELECTRIC FIELD AND DENSITY BETWEEN 6:51.30 AND 6:53.00. NO DETECTION ON THE GROUND

27 Courtesy of Denys Pidyachiy Stanford MSONIC WAVE DETECTION

28 STIMULATED ULF EMISSION ? Stimulated Ion Precipitation ?

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