Thermal Energy Budget of Electrons in the Inner Heliosphere: Parker Solar Probe Observations

被引:11
作者
Abraham, Joel B. [1 ]
Verscharen, Daniel [1 ]
Wicks, Robert T. [2 ]
Agudelo Rueda, Jeffersson A. [3 ]
Owen, Christopher J. [1 ]
Nicolaou, Georgios [1 ]
Jeong, Seong-Yeop [2 ]
机构
[1] Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England
[2] Northumbria Univ, Dept Math Phys & Elect Engn, Newcastle Upon Tyne NE1, Northumberland, England
[3] Dartmouth Coll, Dept Phys & Astron, Hanover, NH 03755 USA
基金
英国科学技术设施理事会; 美国国家科学基金会;
关键词
WIND; TURBULENCE; INSTABILITIES; DISSIPATION; GRADIENTS; STREAMS; AU;
D O I
10.3847/1538-4357/ac9fd8
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present an observational analysis of the electron thermal energy budget using data from Parker Solar Probe. We use the macroscopic moments, obtained from our fits to the measured electron distribution function, to evaluate the thermal energy budget based on the second moment of the Boltzmann equation. We separate contributions to the overall budget from reversible and irreversible processes. We find that an irreversible thermal energy source must be present in the inner heliosphere over the heliocentric distance range from 0.15 to 0.47 au. The divergence of the heat flux is positive at heliocentric distances below 0.33 au, while beyond 0.33 au, there is a measurable degradation of the heat flux. Expansion effects dominate the thermal energy budget below 0.3 au. Under our steady-state assumption, the free streaming of the electrons is not sufficient to explain the observed thermal energy density budget. We conjecture that the most likely driver for the required heating process is turbulence. Our results are consistent with the known nonadiabatic polytropic index of the electrons, which we measure as 1.18 in the explored range of heliocentric distances.
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页数:8
相关论文
共 61 条
[1]   Radial Evolution of Thermal and Suprathermal Electron Populations in the Slow Solar Wind from 0.13 to 0.5 au: Parker Solar Probe Observations [J].
Abraham, Joel B. ;
Owen, Christopher J. ;
Verscharen, Daniel ;
Bakrania, Mayur ;
Stansby, David ;
Wicks, Robert T. ;
Nicolaou, Georgios ;
Whittlesey, Phyllis L. ;
Rueda, Jeffersson A. Agudelo ;
Jeong, Seong-Yeop ;
Bercic, Laura .
ASTROPHYSICAL JOURNAL, 2022, 931 (02)
[2]  
Agudelo Rueda J.A., 2022, THESIS UCL U COLL LO
[3]   Energy Transport during 3D Small-scale Reconnection Driven by Anisotropic Plasma Turbulence [J].
Agudelo Rueda, Jeffersson A. ;
Verscharen, Daniel ;
Wicks, Robert T. ;
Owen, Christopher J. ;
Nicolaou, Georgios ;
Germaschewski, Kai ;
Walsh, Andrew P. ;
Zouganelis, Ioannis ;
Vargas Dominguez, Santiago .
ASTROPHYSICAL JOURNAL, 2022, 938 (01)
[4]   Three-dimensional magnetic reconnection in particle-in-cell simulations of anisotropic plasma turbulence [J].
Agudelo Rueda, Jeffersson A. ;
Verscharen, Daniel ;
Wicks, Robert T. ;
Owen, Christopher J. ;
Nicolaou, Georgios ;
Walsh, Andrew P. ;
Zouganelis, Ioannis ;
Germaschewski, Kai ;
Vargas Dominguez, Santiago .
JOURNAL OF PLASMA PHYSICS, 2021, 87 (03)
[5]   A Solar Source of Alfvenic Magnetic Field Switchbacks: In Situ Remnants of Magnetic Funnels on Supergranulation Scales [J].
Bale, S. D. ;
Horbury, T. S. ;
Velli, M. ;
Desai, M. I. ;
Halekas, J. S. ;
McManus, M. D. ;
Panasenco, O. ;
Badman, S. T. ;
Bowen, T. A. ;
Chandran, B. D. G. ;
Drake, J. F. ;
Kasper, J. C. ;
Laker, R. ;
Mallet, A. ;
Matteini, L. ;
Phan, T. D. ;
Raouafi, N. E. ;
Squire, J. ;
Woodham, L. D. ;
Woolley, T. .
ASTROPHYSICAL JOURNAL, 2021, 923 (02)
[6]   ELECTRON HEAT CONDUCTION IN THE SOLAR WIND: TRANSITION FROM SPITZER-HARM TO THE COLLISIONLESS LIMIT [J].
Bale, S. D. ;
Pulupa, M. ;
Salem, C. ;
Chen, C. H. K. ;
Quataert, E. .
ASTROPHYSICAL JOURNAL LETTERS, 2013, 769 (02)
[7]   Measurement of the electric fluctuation spectrum of magnetohydrodynamic turbulence [J].
Bale, SD ;
Kellogg, PJ ;
Mozer, FS ;
Horbury, TS ;
Reme, H .
PHYSICAL REVIEW LETTERS, 2005, 94 (21)
[8]   Energy dissipation in turbulent reconnection [J].
Bandyopadhyay, R. ;
Chasapis, A. ;
Matthaeus, W. H. ;
Parashar, T. N. ;
Haggerty, C. C. ;
Shay, M. A. ;
Gershman, D. J. ;
Giles, B. L. ;
Burch, J. L. .
PHYSICS OF PLASMAS, 2021, 28 (11)
[9]   Electron and proton heating by solar wind turbulence [J].
Breech, B. ;
Matthaeus, W. H. ;
Cranmer, S. R. ;
Kasper, J. C. ;
Oughton, S. .
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2009, 114
[10]   The Solar Wind as a Turbulence Laboratory [J].
Bruno, Roberto ;
Carbone, Vincenzo .
LIVING REVIEWS IN SOLAR PHYSICS, 2013, 10 (02) :7-+