What is New in the Outer Heliosphere?: Voyager and IBEX

What is New in the Outer Heliosphere?: Voyager and IBEX Marty Lee Durham, New Hampshire USA 1

Our Local Interstellar Environment From E. Möbius

Pogorelov et al., 2008

Plasma & Neutral Parameters R = 1 AU R = 100 AU LISM n p 5 cm -3 V sw 400 km/s B 0 5 10 5 G V A 40 km/s n He 0.015 cm 3 n p 1 10 3 cm 3 V sw 300 km/s B 0 0.3 10 6 G V A 20 km/s n H 0.1cm -3 n He 0.015 cm 3 n p 0.05 cm -3 V ISM 23(?) km/s B 0 3 10 6 (?)G V A 22(?) km/s n H 0.2 cm -3 n He 0.015 cm 3 4

Voyagers 1&2: Still Exploring! 5

Voyager Trajectories Fig. by J. Richardson 15-Apr-13 AIAC12 6

IBEX Spacecraft Simple sun-pointed spinner (4 rpm) Two huge aperture single pixel ENA cameras: IBEX-Lo (~10 ev to 2 kev) IBEX-Hi (~300 ev to 6 kev) E. Möbius, UNH SSC, for the IBEX Team Colloquium Wesleyan University,

Termination Shock is Special plasma pickup ion neutral CR 8

Adventures in the Outer Heliosphere Where is the Shock and ACRs? ISM Gas Parameters No Heliospheric Bow Shock First Measurement of Primary ISM H Hydrogen Deflection Plane (Lallement) The IBEX Ribbon Heliosheath V r ~ 0 The Heliocliff First Measurement of Low-Energy GCRs

Voyager 1 Ions Decker et al., 2005

Stone et al., 2008

Termination Shock Plasma Data At Voyager 2 Richardson et al., 2008

Pickup Ion Distribution in SW v y 0 V sw v x

Voyager 1 Downstream Spectra Stone et al., 2005

Stone et al., 2005 15

Current Sheets & Reconnection Pogorelov et al., 2009 16

Particle acceleration Pumping Mechanism Island merging & contraction Fisk & Gloeckler 2010 Particles are accelerated by a series of adiabatic compressions and expansions, in which the particles can escape from a compression region. Fermo, Drake, Swisdak, 2010 Particles are accelerated by merging and Contracting islands.

Ideas of Particle Acceleration (cont.) Credit: NASA

Diffusive Shock Acceleration

The Blunt Termination Shock McComas and Schwadron, 2006

Blunt Shock: 2D Simulation for ACR energies TS is offset circe, small cross field diffusion: η=0.02 ACR flux increases into the Heliosheath V-2 V-1 Spectrum gradually unfolds Kota, 2010

(New) Puzzles and Controversies Where is the Shock and ACRs? ISM Gas Parameters No Heliospheric Bow Shock First Measurement of Primary ISM H Hydrogen Deflection Plane (Lallement) The IBEX Ribbon Heliosheath V r ~ 0 The Heliocliff First Measurement of Low-Energy GCRs

IBEX Observes He and H 23

Flow Latitude Distribution 24

Flow Longitude Distribution 25

Basic Equations (μ<1 and μ>1) 3 f (v,, )(V E / n) ( t) 3/2 exp t 1 v 2 2r 1 2 (1 ) v ISM 2v ISM [v 2 2r 1 (1 )] 1/2 cos cos cos sin [cos cos sin sin sin ] exp r(vsin ) 1 cos 1 (cos ) cos 2 1 rv 2 (1 ) 1 sin 2 r 2 v 3 (1 ) 2 v 2 2r 1 (1 ) 1/2 sin 2 cos rv 2 sin 2 rv2 sin cos (1 ) 1 2 [rv 2 (1 ) 1 1] 2 sin 2 cos 2 1/2 rv 2 1 2 1/2 rv 2 1 sin2 1 sin

Sun to Earth Frame V cos V 'cos ' V sin sin V 'sin 'sin ' V sin cos V 'sin 'cos ' V E

'/ Helium Integrated Intensity ' / 2 t 0.03 v ISM 0.75 0 0 5 IBEX Frame /

Peak in Latitude 3 f (v,, )(V E / n) ( t) 3/2 exp t 1 v 2 2 2 v ISM 2v ISM (v 2 2) 1/2 sin sin cos( ) 2lnv' v 1 cos 1 (v 2 1) 1 cos cos 0 sc v 0 (v 0 1) sin v 2 0 ( z cos 0 sc E sin 0 sc ) sin( (v 0 1)(v 2 0 2) 1/2 sin 0 ) Independent of Ionization Rate 1

Best ISM He Parameters ISM 79.0 0.47 ISM 4.98 0.21 ISM 75.4 0.4 Witte, 2004 V ISM 23.2 0.3 kms 1 T ISM 6300 390 K McComas et al., 2012 32

No Bow Shock! McComas et al., 2012 34

Interstellar Hydrogen Schwadron et al., 2013 36

Hydrogen Speed, Temperature and λ Schwadron et al., 2013 37

Radiation Pressure on H Schwadron et al., 2013 38

Lyman-α Backscatter Lallement et al., 2005 40

Origin of Secondaries

Primary and Secondary H 42 Pogorelov et al., 2008

IBEX Reveals the Ribbon

The View with IBEX - 2009 SWRI/Adler Planetarium

Secondary ENAs as Source for the IBEX Ribbon Heerikhuisen et al., 2009 11/29/2013 ASTRONUM 2012, Hawaii 47

Voyager in the Transition Layer Zero radial outflow! Increase of tangential speed Krimigis et al., 2011

Time-Dependent Heliosheath Pogorelov et al., 2012 50

Voyager at the Heliopause?

Voyager 1, 2012/183-2013/98: Galactic cosmic rays enter the high-b regions, while low-energy heliosheath particles leave via magnetic connection to LISM 15-Apr-13 AIAC12 53

Voyager 1: Heliosheath particles escape, GCRs enter & B increases 15-Apr-13 AIAC12 54

Voyager 1: Angular distributions of protons 3.4-17.6 MeV (1-d avg.) 2012/183-330 15-Apr-13 AIAC12 55

Voyager in the Heliosheath Burlaga et al., 2013 Image credit: NASA/JPL- Caltech/GSFC/University of Delaware

Burlaga et al., 2013 Image credit: NASA/JPL- Caltech/GSFC/University of Delaware Magnetic Field Observations Conclusions: Increase of the magnetic field magnitude. NO change in the magnetic field orientation. Parker Spiral magnetic field

The Current Picture of the Heliosphere McComas et al. 2012