Detection of Energetic Particles in the Outer Heliosphere and its Boundaries

Abstract

The origin，acceleration and propagation of energy particles in the heliosphere/solar system has always been one of key frontier topics in physics and space physics. An exploration of the outer heliosphere and local interstellar medium will provide crucial information to investigate this frontier topic. In its boundaries，the energy particles originating from the heliosphere are mainly divided into two groups: solar wind suprathermal particles and energy neutral atoms（ENAs）. These energy particles can strongly mediate the morphology and dynamics of the outer boundaries of heliosphere. However，key observations is still lacking，suah as in-situ detection of solar wind suprathermal particles and ENA imaging in the outer boundaries of heliosphere. Based on the high-resolution detection of solar wind suprathermal particles and high-resolution ENA imaging of the Earth’s magnetosphere by the STE instrument on the STEREO satellite，a new-generation semiconductor detectors with low energy thresholds is proposed，combined with the RHESSI’s imaging concept to achieve the ENA imaging and in situ observations of suprathermal particles with high time，energy and angle resolutions in the outer heliosphere. These observations will provide key information to understand the dynamic evolution of the interaction between the heliopshere and local interstellar medium，as well as the origin，acceleration，and propagation of energy particles in the heliosphere.

Keywords

energetic partilces / outer boundaries of the heliosphere / energetic particle detection in space

References

[1] AXFORD W I. The interaction of the solar wind with the interstellar medium[R]. USA：NASA，1972.
[2] BARANOV V B. Gasdynamics of the solar wind interaction with the interstellar medium[R]. Space Science Reviews，1990，52：89-120.
[3] BARANOV V B,MALAMA Y G. The model of the solar wind interaction with the local interstellar medium:numerical solution of self-consistent problem[J]. Journal of Geophysical Research,1993,98:15157-15163
[4] BARANOV V B,MALAMA Y G. Effect of local interstellar medium hydrogen fractional ionization on the distant solar wind and interface region[J]. Journal of Geophysical Research,1995,100:14755-14761
[5] STONE E C,CUMMINGS A C,MCDONALD F B,et al. Voyager 1 explores the termination shock region and the heliosheath beyond[J]. Science,2005,309(5743):2017-2020
[6] Stone E C,CUMMINGS A C,MADONALD F B,et al. An asymmetric solar wind termination shock[J]. Nature,2008,454(7200):71-74
[7] MCCOMAS D J,ALLEGRINI F,BOCHSLER P,et al. Global observations of the interstellar interaction from the Interstellar Boundary Explorer(IBEX)[J]. Science,2009,326(5955):959-962
[8] WANG L H,LIN R P,SALEM C,et al. Quiet-time interplanetary ~2–20 kev superhalo electrons at solar minimum[J]. The Astrophysical Journal Letters,2012,753(1):1-6
[9] Montgomery M D,BAME S J,HUNDHAUSEN A J,et al. Solar wind electrons:vela 4 measurements[J]. Journal of Geophysical Research,1963,73(15):4999-5003
[10] ROSENBAUER H,SCHWENN R,MARSCH E,et al. A survey on initial results of the HELIOS plasma experiment[J]. Journal of Geophysical Research,1977,42(6,19):561-580
[11] PILIPP W G,MIGGENNIEDER H,MONTGOMERY M S,et al. Characteristics of electron velocity distribution functions in the solar wind derived from the helios plasma experiment[J]. Journal of Geophysical Research,1987,92(A2):1075-1092
[12] PIERRARD V,MAKSIMOVIC M,LEMAIRE J. Core,Halo and Strahl electrons in the solar wind[J]. Astrophysics and Space Science,2001,277:195-200
[13] MAKSIMOVIC M,ZOUGANELIS I,CHAUFRAY J Y,et al. Radial evolution of the electron distribution functions in the fast solar wind between 0.3 and 1.5 AU[J]. Journal of Geophysical Research,2005,110(A9):1-9
[14] TAO J W,WANG L H,ZONG Q G,et al. Quiet-time suprathermal(~0.1–1.5 kev)electrons in the solar wind[J]. The Astrophysical Journal,2016,820(1):1-10
[15] STVERAK S,MAKSIMOVIC M,TRAVNICEK P M,et al. Radial evolution of nonthermal electron populations in the low-latitude solar wind:helios,cluster,and Ulysses observations[J]. Journal of Geophysical Research:Space Physics,2009,114(A5):1-15
[16] FELDMAN W C,ASBRIDGE J R,BAME S J,et al. Upper limits for the solar wind He+ content at 1 AU[J]. Journal of Geophysical Research,1974,79(13):1808-1812
[17] MAKSIMOVIC M，BALE S D，VAIVADS A，et al. A radio and plasma wave experiment for the solar orbiter mission[C]//Second Solar Orbiter Workshop. Athens，Greece：ESA，2007.
[18] SCUDDER J D,OLBERT S. A theory of local and global processes which affect solar wind electrons 2. experimental support[J]. Journal of Geophysical Research,1979,84(A11):6603-6620
[19] MAKSIMOVIC M,PIERRARD V,RILEY P. Ulysses electron distributions fitted with Kappa functions[J]. Geophysical Research Letters,1997,24(9):1151-1154
[20] PIERRARD V,MAKSIMOVIC M,LEMAIRE J. Electron velocity distribution functions from the solar wind to the corona[J]. Journal of Geophysical Research,1999,104(A8):17021-17032
[21] YOON P H,RHEE T,RYU C M. Self-consistent formation of electron κ distribution:1. Theory[J]. Journal of Geophysical Research:Space Physics,2006,111(A9):1-10
[22] WANG L H,LIU G,HE J S,et al. Solar wind ~20–200 keV superhalo electrons at quiet times[J]. The Astrophysical Journal Letters,2015,803(1):1-6
[23] YANG L,WANG L H,LI G,et al. The angular distribution of solar wind superhalo electrons at quiet times[J]. The Astrophysical Journal Letters,2015,811(1):1-6
[24] PARKER E N. Nanoflares and the Solar X-Ray Corona[J]. The Astrophysical Journal,1988,330:474-479
[25] YANG L P,WANG L H,HE J S,et al. Numerical simulation of superhalo electrons generated by magnetic reconnection in the solar wind source region[J]. Research in Astronomy and Astrophysics,2015,15(3):348-362
[26] YOON P H,ZIEBELL L F,GAELZER R,et al. Langmuir turbulence and suprathermal electrons[J]. Space Science Reviews,2012,173:459-489
[27] ZANK G P,HUNANA P,MOSTAFAVI P,et al. Diffusive shock acceleration and reconnection acceleration processes[J]. The Astrophysical Journal,2015,814(2):137-160
[28] ZANK G P. Pickup ion-mediated plasma physics of the outer heliosphere and very local interstellar medium[J]. Geoscience Letters,2016,3(22):1-17
[29] MEWALDT R A，MASON G M，GLOECKLER G，et al. Long-term fluences of energetic particles in the heliosphere[C]//Proceedings of the 27th International Cosmic Ray Conference. Hamburg，Germany：The Auspices of the International Union of Pure and Applied Physics（IUPAP），2001.
[30] MASON G M，DESAI M I，MAZUR J E，et al. Energetic particles accelerated by shocks in the heliosphere：what is the source material?[C]//The Physics of Collisionless Shocks：4th Annual IGPP International Astrophysics Conference. [S. l.]：IGPP，2005.
[31] GLOECKLER G，FISK L. Acceleration of low‐energy ions in the quiet‐time solar wind and at the termination shock[J]. AIP Conference Proceedings. [S. l.]：American Institute of Physics，2006.
[32] GLOECKLER G，FISK L A，MASON G M，et al. Formation of power law tail with spectral index-5 inside and beyond the heliosphere[C]//AIP Conference Proceedings. [S. l.]：American Institute of Physics，2008.
[33] FISK L A,GLOECKLER G. Particle acceleration in the heliosphere:implications for astrophysics[J]. Space Science Reviews,2012,173:433-458
[34] MASON G M,GLOECKLER G. Power law distributions of suprathermal ions in the quiet solar wind[J]. Space Science Reviews,2012,172:241-251
[35] GIACALONE J. Energetic charged particles associated with strong interplanetary shocks[J]. Astrophysical Journal,2012,761(1):28-40
[36] DAYEH M A,DESAI M I,DWYER J R,et al. Composition and spectral properties of the 1 AU quiet-time suprathermal ion population during solar cycle 23[J]. Astrophysical Journal,2009,693:1588-1600
[37] FISK L A,GLOECKLER G. Acceleration of suprathermal tails in the solar wind[J]. Astrophysical Journal,2008,686:1466-1473
[38] ZHANG M. Acceleration of suprathermal particles by compressional plasma wave trains in the solar wind[J]. Journal of Geophysical Research Space Physics,2010,115(A12):1-12
[39] DRAKE J F,SWISDAK M,FERMO R. The power-law spectra of energetic particles during multi-island magnetic reconnection[J]. Astrophysical Journal,2012,763(1):1-13
[40] ZANK G P,LE ROUX J A,WEBB G M,et al. Particle acceleration via reconnection processes in the supersonic solar wind[J]. Astrophysical Journal,2014,797(1):1-18
[41] LIVADIOTIS G,MCCOMAS D J. Beyond kappa distributions: exploiting Tsallis statistical mechanics in space plasmas[J]. Journal of Geophysical Research Space Physics,2009,114(A11):1-21
[42] JOKIPⅡ J R,LEE M A. Compression acceleration in astrophysical plasmas and the production of f(v)~ v-5 spectra in the heliosphere[J]. Astrophysical Journal,2010,713(1):475-483
[43] SCHWADRON N A,DAYEH M A,DESAI M I,et al. Superposition of stochastic processes and the resulting particle distributions[J]. Astrophysical Journal,2010,713(2):1386-1392
[44] Decker R B,KRIMIGIS S M,ROELOF E C,et al. Voyager 1 in the foreshock,termination shock,and heliosheath[J]. Science,2005,309(5743):2020-2024
[45] RICHARDSON J D. Weak termination shock decelerates upstream solar wind but heliosheath plasma is cool[J]. Nature,2008,454:63-66
[46] GRUNTMAN M,ROELOF E C,MITCHELL D G,et al. Energetic neutral atom imaging of the heliospheric boundary region[J]. Journal of Geophysical Research,2001,106(A8):15767-15781
[47] MCCOMAS D J,FUSELIER S A,SCHWADRON N A. Local interstellar medium:six years of direct sampling by IBEX[J]. The Astrophysical Journal Supplement Sereries,2015,220(2):1-11
[48] KRIMIGIS S M,MITCHELL D G,ROELOF E C,et al. Imaging the interaction of the heliosphere with theinterstellar medium from Saturn with Cassini[J]. Science,2009,326(5955):971-973
[49] GLASER D L，HALEKAS J S，TURIN P，et al. STEIN（SupraThermal Electrons，Ions and Neutrals），a new particle detection instrument for space weather research with cubesats[C]//23rd Annual AIAA/USU Conference on Small Satellites. [S.l.]：AIAA，2009.