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FUNDAMENTAL PHYSICS ISSUES ONRADIATION BELTS ANDREMEDIATIONPresentation to Dr. Bobby JunkerDENNIS PAPADOPOULOSUNIVERSITY OF MARYLANDAugust 4, 20091

The Team – Budget - Reviews Leadership––––– UMCP – Dennis Papadopoulos - Professor of Physics– Overall DirectionStanford University – Umran Inan - Professor of Electrical Engineering –Field testsUCLA – Walter Gekelman – Professor of Physics – Laboratory experimentsVa Tech – Wane Scales – Professor, Computer and Electrical Engineering – Particle and hybridelectromagnetic codes (Physics codes) – Support to SPIDERDartmouth – Anatoly Streltsov – Associate Professor of Engineering – Global numerical models(engineering codes)Ten Post-Docs and Research ScientistsTwelve graduate studentsSeven senior visitorsFifteen undergraduate studentsBudget* Actual **PlannedFY 07FY 08FY 09FY 10FY 11 1.5 M* 1.5 M* 1.5 M* 1.5 M** 1.5 M**Dates and location of Major Reviews/Meetings:1.Kick-off meeting June 5, 2007 University of Maryland2.Review March 3, 2008 UCLA Conf. Center, Lake arrowhead Ca3.Review February 18, 2009 Stanford UniversityReviews combined with DSXprogram review2

ES DGROUNDDATA BASICPHYSICSOFPOTENTIALRBRSYSTEMS HEMICALS ATION THEORY&LABEXPERIMENTSOFNOVELANTENNACONCEPTS ASIMPORTANTTONATIONALDEFENSE3

DoD Benefits Prevent loss of Low Earth Orbiting(LEO) satellites in case of deliberateor accidental High Altitude NuclearDetonation (HAND) [DSX – SPIDER]104105106Teq 4 yr 108 Increase lifetime and functionality ofsatellites by reducing the trappedenergetic proton population – SEUmajor issue due to wide use ofsubmicron Commercial-Off-The-Shelf(COTS) Electronics – (e.g. seeVanderbilt AFOSR MURI) Develop broadband, efficient, globalULF/ELF/VLF sources4

Physics & Technology Challenges Radiate - Inject efficiently from space or ground VLF/ELF/ULF waves in the inearth-ionosphere waveguide and the RB Ionospheric Current Drive Performance of electric dipole antennas at VLF in plasmas (DSX - AF) VLF generation in RB by injecting low ionization chemicals (SPIDER - NRL) Innovative Injection Concepts – Rotating Magnetic Field (RMF) Propagate – Guide waves to regions of enhanced RB Injection to naturally occurring ducts Generation of artificial ducts by ionospheric heaters (HAARP) Amplify – Use the free energy stored in trapped energetic particles to amplify theVLF wave power The physics of Artificially Stimulated Emissions (ASE) Precipitate – Physics of particle precipitation with wave particle interactions The physics of slot formation The physics of energetic proton loss5

Technical Approach Combine extensive simulations using newly developed codes and analytictheory, laboratory experiments using the LAPD plasma chamber at UCLA, fieldexperiments using the HAARP facility and ground VLF stations, and satellite andground based VLF and ULF diagnostics – MULTI-DISCIPLINARY EFFORTHAARPDEMETERLAPDCONJUGATE BUOYSDMSP6

Technical Accomplishments- Transition toDoD Applications First models of enhanced RB proton precipitation– Design of a ground based Proton RBR system – DARPA conducted environmentalimpact study in anticipation of new start First demonstration of ionospheric generation of ELF/ULF waveswithout relying on electrojet currents (HF to ELF/ULF conversion)– Simultaneous detection in Alaska-Seattle-Hawai-Guam ( 8Mm)– Injection in the magnetosphere of more than 5 kW ULF power– Spin-off – PACE-New concept for HED current drive – 30-50 dB more efficient thantraditional ELF/ULF radiators – First test (DARPA seedling) in August, 2009 First laboratory demonstration of high efficiency antenna radiation inplasma using Rotating Magnetic Fields (RMF) Laboratory resolution of controversy of electric dipole antennaradiation efficiency – AF DSX mission antenna design support New 2-D off plane code provided guidance to NRL’s SPIDER test Global effects of VLF transmitters – VLF mode conversion to LHW7

Technical Accomplishments (cont.) Amplification – Artificially Stimulated Emissions (ASE)– Empirical ASE model using the Stanford Sipple facility digitized data– MURI-DARPA joint ASE tests using HAARP/Conjugate buoy system ( 20 dBamplification)– Joint NRL-MURI modeling optimizes probability of ASE gain– New ASE targeted experiments using Alpha (Russian) VLF transmitter (inner RB)– Generation of artificial propagation ducts using HAARP with Demeter detection Light- Induced Electron Precipitation(LEP)– New Demeter measurements reveal it as key to slot maintenance– New global detection of LEP via VLF paths– Global effects of VLF transmitters – Irregularity triggering -VLF mode conversionto Lower Hybrid Waves – Possible proton precipitation Development of new efficient numerical simulation codes– Three dimensional MHD, EMHD, whistler and hybrid codes simulating VLF/ELF/ULF generation and injection and modeling precipitation– Many of the codes implemented on new GPU processors (game platforms)accelerating their performance by factors between 20-508

Ionospheric Current Drive (ICD)A little historyLowerIonosphere Circa 1973IONOSPHEREE HED / EVED kδElightningGroundHk HEDEHk1ALTERNATIVE (1974): MODULATE EJETCONDUCTIVITY – PEJ.DEMOSTRATED IN TROMSO, HAARP, HIPASHFPONDEROMOTIVE FORCE CURRENT DRIVETHRESHOLD - EITHER VERY OBLIQUE HEATERSOR TOO MUCH POWERHall regionIssues with PEJ; Availability, sitting,efficiency, long propagation pathConductivity modulation à ejet currentmodulation à large virtual ELF/VLF antenna9

Summary Stanford VLF Results1.Far Prop: Midway 4.5 MmPEJ Excitation2. Coherent Painting -TWTPulse Scan, Mar-13-01, mine-ns-0700ut0.250.20.150.1field (pT)0.050-0.05-0.1-0.15-0.2-0.25Pap. Wallace 2001, increaseefficiency, directionalityMoore et al.GRL, 2008050010001500time (µS)Tdet 1 sec3. Art. Stim. EmissionsOnly the pulse at 1100 Hz is amplified10 dB/secStanford - New HARP - Cohen et al. 200910

PEJ ULF Generation and PropagationGakona 1 Hz, 9.9 pTJuneau, 800 km30 dB lossEvanescentAlfvenic Duct -IARv1Gakona 15 HzE1Chiniak, 670 km3 dB losspropagatingBoShear AlfvenWave –FieldGuidedDetection by DEMETER with E 5-10 mV/m confined to field tube11

ICD a glimpse at ULFULF vs. 1 kHz Amplitude [April 24 - April 30, 2007]B( f 1kHz ) / B(1kHz ) 114Marker of PEJgenerationULF Amplitude (pT)1210864200 Boδp12345671 kHz Amplitude (pT) J JMHAARPCollisionless heating drivesisotropic Magnetosonic waver rΔJ : Bo p12

ICD Confirmedt 2.4sMay 2009simultaneousmeasurementsat 3.8 HzE 8 Mm5000kmDEMETER 1 mV/mE120 kmjHjP80 kmBGround signaturedue to jHTransducerHall region –Plasmasimilar tosemiconductor13

EquatorialICD JBoF-regionσ H E σ P EV 0E V / E σ H /σ P 20 δ pj P σ P E σ H E V [[1 (σ H /σ P ) 2 ]E System by about 400 timesmore efficientEE-regionBEV Current closure through field aligned heliconsInteresting potential systembut maximum frequencylimited by F-regionresponse time to may-below ELFGroundImage current doubles signal14

ICD at VLF/ELF FrequenciesArtificially Constructed Electrojet (ACE)EquatorBEmVEV HEDGroundnA/m2Incident pulse .1 mV/m or 1 nT15

Equatorial ICD - ModelingField alignedhelicon drivencurrent closureIL 3x107 A-mImage current increases field by factor of 2Eliasson and Pap, JGR 200916

Getting .1 mV field at 75 kmE (75km) ( IL / 2 106 A m)(δ / 75km)mV / mSkin depth km likeConductivity dependent75 kmIL 2 105 (75km / δ ) A mGet rid of 75/δ factorILδUse pulsed antennasneak-through conceptACE to PACE17

Sneak- ‐throughConcept„1.0Antennapulse0.8h 75 kmto h/c 250 µsecs0.61 Exp[ t /T]Final pulse0.40.2δeff/h 2Reduces IL to464x105 A-m8Optimum medium seawaterT secs4110. 10. 01.10. 001.01.00110 - ‐ 4Concept to be tested in September – DARPA seedlingPeder Hansen10 - ‐ 50. 10. 20. 30. 40. 5L kmt18T

Technical Accomplishments- Transition toDoD Applications First models of enhanced RB proton precipitation– Design of a ground based Proton RBR system – DARPA conducted environmentalimpact study in anticipation of new start First demonstration of ionospheric generation of ELF/ULF waveswithout relying on electrojet currents (HF to ELF/ULF conversion)– Simultaneous detection in Alaska-Seattle-Hawai-Guam ( 8Mm)– Injection in the magnetosphere of more than 5 kW ULF power– Spin-off – PACE-New concept for HED current drive – 30-50 dB more efficient thantraditional ELF/ULF radiators – First test (DARPA seedling) in August, 2009 First laboratory demonstration of high efficiency antenna radiation inplasma using Rotating Magnetic Fields (RMF) Laboratory resolution of controversy of electric dipole antennaradiation efficiency – AF DSX mission antenna design support New 2-D off plane code provided guidance to NRL’s SPIDER test Global effects of VLF transmitters – VLF mode conversion to LHW19

PRBR–TheInnerBeltProtonsStarfishprotonsE 20-100MeVBermuda Triangle of SatellitesSAAL 1.5-1.820

Issues with using COTS in LEOOrbiting Platforms As commercial feature sizes scale down, proton upsetswill become much more frequent Critical charge for upset scales as (feature size)2 For large feature sizes, protons cause upsets by hittingnuclei and releasing secondary particles that depositcharge At 65 nm and smaller, a proton deposits enough chargein silicon to cause an upset directly This can increase the proton SEU cross section by 2-3orders of magnitude for deep submicron devices Major issue for micro-satellites21

nsmiZers scone. esonantwaves–SAWwithfrequencyinthe1–15Hzband. wly( - ‐2yearsevery10years)aswellasmonitored lleviatecurrentproblems opoulosandShao,Gomtact2009;Shaoetal.,JGR2009)22

Schema.cofPRBRConceptMaintain an average amplitudeof approximately 25 pT of ShearAlfven Waves (SAW) with 5-15Hz frequency in the L 1.5-1.8shells of the inner belt. Thesewaves induce Pitch AngleDiffusion (PAD) on 30-100 MeVprotons, by satisfying theresonance conditionω k z vz Ωk z vz Ω Energy stored in volume for ΔL .1 is 75 kJSAW injected using groundbased transmitters Loss time for 30-100 MeV protons 3 years Injection power required to maintain itdepends on SAW confinement time 3-7 KW23

HowtoInjectkWLevelSAWPowerGround- ‐basedTransmiZerOp.ons raturesuperconduc.ng)HED b 60( IL2 / 2 1010 )[δ2( L δ )] pT 30( IL2 / 2 1010 ) pT2 A-m2x1010A-m22Need M IL2 2x10RMF b 30(M / 5 109 ) pTNeed RMF with M!5x109 A-m224

AlfvenMasers–TriggeredProtonPrecipita.onPearls - repetitive wave-packets with characteristic frequency drift inside each oneShear Alfven WaveIon CyclotronInstabilityMagnetospheric ResonatorConjugate stations detect antiphased pearl wave-packets25

AnyEvidence?26

Technical Accomplishments (cont.) Amplification – Artificially Stimulated Emissions (ASE)– Empirical ASE model using the Stanford Sipple facility digitized data– MURI-DARPA joint ASE tests using HAARP/Conjugate buoy system ( 20 dBamplification)– Joint NRL-MURI modeling optimizes probability of ASE gain– New ASE targeted experiments using Alpha (Russian) VLF transmitter (inner RB)– Generation of artificial propagation ducts using HAARP with Demeter detection Light- Induced Electron Precipitation(LEP)– New Demeter measurements reveal it as key to slot maintenance– New global detection of LEP via VLF paths– Global effects of VLF transmitters – Irregularity triggering -VLF mode conversionto Lower Hybrid Waves – Possible proton precipitation Development of new efficient numerical simulation codes– Three dimensional MHD, EMHD, whistler and hybrid codes simulating VLF/ELF/ULF generation and injection and modeling precipitation– Many of the codes implemented on new GPU processors (game platforms)accelerating their performance by factors between 20-5027

ThePhysicsoftheGapForma.onMore than 15 dB lower values of VLF from Navy Transmitters. Cannotcause gap. What about lightning ?28

LEP as Benchmark for RBRAssessments Lightning- radiaAonbeltlossintheinner- ‐beltandslotregions ontheground QuanAficaAonofwave- stsbemeasuredtogetherwithwhistler- ‐modewaves avesofintensiAesof 10to200pT ificantlyaffectelectronlifeAmes29