1 / 36

E. Möbius

E. Möbius with H. Kucharek, M. Bzowski, L. Saul, P. Wurz, S. Fuselier, V. Izmodenov, D. McComas, H.-R. Müller, D. B. Alexashov. DIAGNOSTICS OF THE LOCAL INTERSTELLAR MEDIUM AND ITS INTERACTION WITH THE HELIOSPHERE FROM WITHIN. Thanks to: IBEX Team and NASA SMEX Office ISSI He and H Team.

clay
Télécharger la présentation

E. Möbius

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. E. Möbius with H. Kucharek, M. Bzowski, L. Saul, P. Wurz, S. Fuselier, V. Izmodenov, D. McComas, H.-R. Müller, D. B. Alexashov DIAGNOSTICS OF THE LOCAL INTERSTELLAR MEDIUM AND ITS INTERACTION WITH THE HELIOSPHERE FROM WITHIN Thanks to: IBEX Team and NASA SMEX OfficeISSI He and H Team CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  2. Neutral LIC Flow Diagnosticswith IBEX • IntroductionInformation Imprinted on Interstellar Gas Flow, previous Observations & current Knowledge • New Observation Method- IBEX Mission Configuration and Simulations- IBEX Instrumentation and Sensitivity- IBEX Orbit Strategy- IBEX In-Flight Performance • Summary & Conclusions Overview CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  3. Interstellar Gas Penetrates the Barrier Rosetta Nebula 1967 ≈700 AU Fahr 1967 Showed that in-situ observationof the LIC is possible at 1 AU! “Strömgren Sphere” CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  4. Information in the Interstellar Gas Flow 3 In-Situ Methods - UV Backscattering - integral, - hard to calibrate + global info - Pickup Ions - lost velocity info + composition - Neutral Imaging + full distribution - hard to do few species mvB2/2 ≈ GmMs/Rat ≈ 1.3 AU Velocity Vector fromKinematics of Local Flow and Density Pattern Jmax/Jo: ISM Temperature VISM Opens With IBEX Jo: ISM Density CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  5. Pristine LIC State from He with 3 Methods(Efforts of an ISSI Team) He Parameters from Neutral Gas, Pickup & UV Scattering • VHe= 26.3 km/s; THe = 6300 K; nHe = 0.015 cm-3 Neutral Image(V, T, NHe) Let’s Turn to other Species! Neutral Gas Observations provide most accurate and detailed information CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  6. Plasma Interaction with the LIC Plasma Density Contours Blue & Green Solar Wind Bow Shock? He He Termination Shock ISM ≈ 26 km/s H & O Charge Exchange O, H slow & hot H+, O+ Heliopause ISM Orange - Pristine ISM Red - Decelerated ISM 3D MHD Model T. Linde, Thesis CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  7. LIC He State & H Density at TS (2 ISSI Teams) Combine He Parameters, TS Distance & H Density at the TS To infer H and H+ Densities in the LIC • SW Slowdown Richardson et al.: 0.09±0.02 cm-3Includes Uncertainties in Model & Parameters • UV Scattering Pryor et al.: 0.09±0.024 cm-3Modulation Damping; Incl. Observ. & Model Uncertainties • Pickup Ions Bzowski et al.: 0.087±0.022 cm-3Observation, Model, Ioniz. & Rad. Pressure Uncertainties Key Value: nH from SW Slowdown, UV Scattering & Pickup • Voyager Tails Gloeckler et al.: 0.055±0.021cm-3IncludesNHe & relative Uncertainties • Weighted Mean: 0.083±0.023 cm-3 There are still large Uncertainties Let us Expand the He Neutral Observations to H or O! And there is more to gain with Direct Flow Observations!! CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  8. Ly Alpha Observations Have RevealedDeflected Flow of H Asymmetric ISM Magnetic FieldDeflects the Decelerated FlowIzmodenov et al., 2005 H Latitude He Longitude Direct Neutral Observations & 2nd Species Highly Desirable Lallement et al. 2005 CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  9. Pattern of the Interstellar Gas Flow It Has Been Done for He, Revealing the Pristine Flow! Asymmetry Effect IBEX Oxygen will be Displaced, Revealing Deflection & Braking CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  10. Modeling of H & O Flow with ISM Magnetic Field BISM O Flow Deflected by ≈ 1orelative to He Izmodenov From Möbius et al., 2009 CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  11. Pattern of the Interstellar Gas Flow IBEX Oxygen Displaced, Revealing Deflection & Braking Simulated Observationin Longitude after Izmodenov et al., 1996 CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  12. Pattern of the Interstellar Gas Flow Oxygen Displaced, Revealing Deflection & Braking Fall Spring Simulated Flow Angle Difference Trajectory Computation Bzowski et al. CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  13. Neutral Gas Observation, How Does it Work?II. Oxygen + .. • Collimator CameraDirection DeterminationNeed large area: Collimator • Use Surface Conversion into Ions- Need Mass Spectrometer for Species Identification!- Negative Ions: For O, H, (C) Not for N! Is it for He?? • Technique doesn’t Provide E - Use the Sun as Gravitational Spectrometer- Determine Arrival Direction Also for Deflection by ISM Magnetic Field Oo O- CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  14. Imaging of Several Neutral Atom Species What Does it Take to Do this? IBEX-Lo Collimator Diamond-Like Carbon Analyzer Start 1 + Start 2 + Stop Hard DiskCoating e-Start 2 ion ion ion Stop Time-of-Flight foil1 foil2 MCP CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  15. He Represents the Pristine ISM Flow Can it be Observed Simultaneously? Yes, it Can! With Sputter Products Test with Neutral He at UoBern Spring Fall Meta-Stable He IBEX-Lo Wurz et al., 2008 CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  16. IBEX ISM O and He Observation Conditions • IBEX is a Sun-Pointed SpinnerIBEX-lo FoV at 90o to the Sun • Observation Periods:Fall and Spring • Fall: Large Angular Separation of Primary & Secondary O, but low Count RateBecause: Earth recedes from Flow • Spring: Small Angular Separation of Primary & Secondary O, but high Count RateBecause: RAM Direction • Observe O at 540 eV • Observe He at 135 eV (x1500 in Flux; High Sputtering Efficiency) CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  17. IBEX Keeps Orientation for One Full Orbit How Does that Affect the O Observation? • Overlapping Sweeps in Spring CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  18. Simulated O-Flow ObservationFor the Spring Flow Passage O Flow Spring CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  19. IBEX-Lo In-Flight Performance IBEX-Lo TOF Works Great! H & O Easily Identified e Filtered out! Excellent Tool to Tackle Background CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  20. IBEX-Lo In-Flight Performance Arbitrary Orbit 9 Sample No Selection or BackgroundSubtraction! Normalized toISM Flow Viewing Both ISM O & He will be well Visible! First Spring Period Starts Now! CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  21. Conclusions & Outlook • Neutral Atom Imaging is becoming a powerful new window for Local Astrophysics • ISM He Holds Unbiased LIC Account Neutral Gas Observations provide the most detailed and accurate LIC Parameters, in accordance with simultaneous Pickup Ion & UV Observations • ISM H & O - affected by the Heliospheric Interface - hold clues to the interaction with the LIC • IBEX-lo will determine the O Flow distribution in direct comparison with He and relative to star positions, thus providing slowdown, heating, and deflection of the Secondary O component • Flow Signal 2 orders of magnitude above average sample • First Observation Campaign starts now! CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  22. Thank You! CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  23. Neutral AtomsA New Window for Local Astrophysics • Neutral Atoms:Observed up to their Mean Free Pathlength:A few 100 AU in the Neighborhood of the Sun-> Ideal for charting the Heliosphere and its Boundaries-> No Interference from farther away, But Objects outside are also beyond the Neutral Atom Horizon • IBEX takes it up to its Horizon • Neutral Atom Imagingknits another connection between Space Physics & Astrophysics Point Source Diffuse Source CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  24. ISM Neutral Gas In Different ISM Cloud Environments • Hot Cloud like the Local Bubble:No Neutral Gas in the Bubble,Thus No In-Situ Observations • Cold and Dense ISM Clouds:- N ≥ 100 cm-3- He Remains most Important Species at 1 AU- Slowdown of SW inside 1 AU in Focusing Cone “He Comet”- Pickup Ions and Energetic He+ very important at 1 AU Möbius et al., 2006 CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  25. If We Could See Our Heliospherefrom Outside … ISM Gas Flow BZ Cam Spring AGU Mtg 2008 E. Möbius UNH/SSC

  26. Pattern of the Interstellar Gas FlowHe Provides Unbiased LIC Parameters Courtesy M. Witte CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  27. Three Step ApproachInto the Future • 1) Make Use of “S3C Great Observatory” with Coordinated ObservationsACE, SOHO, Wind, Ulysses, Voyagers • 2) Be Innovative at Our Front DoorstepModerately Improved Observation Techniques at 1 AU or up to ≈3 AU IBEX Improve Resolution and Collection Power • 3) Develop Seriously a Probe to the Frontier * Interstellar Probe *It definitely Needs Improved Technology!! Spring AGU Mtg 2008 E. Möbius UNH/SSC

  28. Combined He Cone PUI ObservationsAMPTE, ACE & NOZOMI Sliding 9-Day Averages Daily Averages Solar Minimum 30 – 40 Days Maximum Gloeckler et al., 2004

  29. Strong Variations in Pickup Ion Distributions • Pickup Ion Distributions are Highly Variable • Pickup Ions React to:- IMF Orientation (early Rollover)- IMF Strength (Compression and Rarefaction)- SW Density (Compression and Rarefaction)- Ionization rates &probably several unknown causes • For Deduction of LIC Parameters Mitigation Sought with:- Long Integration Times • Better: Attempt to Understand Causes- Also Provides Handle on Ion Transport and Acceleration • STEREO (also ACE) Provide Simultaneous Observations

  30. STEREO & ACE Now Allow Simultaneous Interstellar He Cone Observations This provides tools to separate spatial & temporal variations STEREO A ACE ≈40oin 2007 STEREO B Ongoing Analysis not discussed here

  31. Pristine LIC State from He with 3 Methods(Efforts of an ISSI Team) Sensitive to Ionization Cone Sensitive to V, T, Ionization J. Raymond G. Gloeckler Neutral Image(V, T, NHe) J. Vallerga SWICSPickup (NHe) Simulation:Courtesy J. Raymond UV Ionization, Solar Illuminationfrom SOHO SEM, EIT and SUMER IndependentCheck on V CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  32. Neutral Imaging Most Accurate & Detailed Spring AGU Mtg 2008 E. Möbius UNH/SSC

  33. Why Did we Start with Interstellar Helium?(and not Hydrogen) • Has the Highest Ionization Potential i.e. Reaches 1 AU • Second Most Abundant Species i.e. Is an Important Species in the LISM • Not Affected by the Heliospheric Interface i.e. Provides an Unbiased Account of the LISM • Could be Observed with 3 Methods First: Neutrals, Pickup, Scattering of Solar UV Spring AGU Mtg 2008 E. Möbius UNH/SSC

  34. IBEX ISM O Observation Conditions • IBEX is a Sun-Pointed SpinnerIBEX-lo FoV at 90o to the Sun • Observation Periods:Fall and Spring • Fall: Large Angular Separation of Primary & Secondary O, but low Count RateBecause: Earth recedes from Flow • Spring: Small Angular Separation of Primary & Secondary O, but high Count RateBecause: RAM Direction CSPAR Conf Voyagers in the Heliosheath Jan 2009 E. Möbius UNH/SSC

  35. IBEX-lo O Conversion EfficiencyFor ISM O Observations • O must be observed in Spring and FallSeparates Heliospheric from Gravitational Deflection • In Fall: O Flux down x4 (lower relative speed) & Efficiency down x20 • But Lo-Res Section can be usedIncreases collection x12 IBEX-Lo Energy Range Fall Spring x 20 Wurz et al., 2006 Spring AGU Mtg 2008 E. Möbius UNH/SSC

  36. Why Bother? Spring AGU Mtg 2008 E. Möbius UNH/SSC

More Related