TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW
Previous models of solar wind heating by interstellar pickup proton-driven turbulence have assumed that the wind speed is a constant in heliocentric radial position. However, the same pickup process, which is taken to provide the turbulent energy, must also decelerate the wind. In this paper, we ext...
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| Định dạng: | Bài viết |
| Ngôn ngữ: | en_US |
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Institute of Physics/American Astronomical Society
2015
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| Truy cập trực tuyến: | http://hdl.handle.net/1721.1/95834 |
| _version_ | 1826200178099486720 |
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| author | Isenberg, Philip A. Smith, Charles W. Matthaeus, William H. Richardson, John D. |
| author2 | MIT Kavli Institute for Astrophysics and Space Research |
| author_facet | MIT Kavli Institute for Astrophysics and Space Research Isenberg, Philip A. Smith, Charles W. Matthaeus, William H. Richardson, John D. |
| author_sort | Isenberg, Philip A. |
| collection | MIT |
| description | Previous models of solar wind heating by interstellar pickup proton-driven turbulence have assumed that the wind speed is a constant in heliocentric radial position. However, the same pickup process, which is taken to provide the turbulent energy, must also decelerate the wind. In this paper, we extend our phenomenological turbulence model to include variable wind speed, and then incorporate the deceleration due to interstellar pickup protons into the model. We compare the model results with plasma and field data from Voyager 2, taking this opportunity to present an extended and improved data set of proton core temperature, magnetic field fluctuation intensity, and correlation length along the Voyager trajectory. A particular motivation for including the solar wind deceleration in this model is the expectation that a slower wind would reduce the resulting proton core temperature in the region beyond ~60 AU, where the previous model predictions were higher than the observed values. However, we find instead that the deceleration of the steady-state wind increases the energy input to the turbulence, causing even higher temperatures in that region. The increased heating is shown to result from the larger values of the ratio of Alfven speed to solar wind speed that develop in the decelerating wind. |
| first_indexed | 2024-09-23T11:32:22Z |
| format | Article |
| id | mit-1721.1/95834 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T11:32:22Z |
| publishDate | 2015 |
| publisher | Institute of Physics/American Astronomical Society |
| record_format | dspace |
| spelling | mit-1721.1/958342022-09-27T20:11:35Z TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW Isenberg, Philip A. Smith, Charles W. Matthaeus, William H. Richardson, John D. MIT Kavli Institute for Astrophysics and Space Research Richardson, John D. Previous models of solar wind heating by interstellar pickup proton-driven turbulence have assumed that the wind speed is a constant in heliocentric radial position. However, the same pickup process, which is taken to provide the turbulent energy, must also decelerate the wind. In this paper, we extend our phenomenological turbulence model to include variable wind speed, and then incorporate the deceleration due to interstellar pickup protons into the model. We compare the model results with plasma and field data from Voyager 2, taking this opportunity to present an extended and improved data set of proton core temperature, magnetic field fluctuation intensity, and correlation length along the Voyager trajectory. A particular motivation for including the solar wind deceleration in this model is the expectation that a slower wind would reduce the resulting proton core temperature in the region beyond ~60 AU, where the previous model predictions were higher than the observed values. However, we find instead that the deceleration of the steady-state wind increases the energy input to the turbulence, causing even higher temperatures in that region. The increased heating is shown to result from the larger values of the ratio of Alfven speed to solar wind speed that develop in the decelerating wind. Jet Propulsion Laboratory (U.S.) (NASA contract 959203) United States. National Aeronautics and Space Administration (NASA grant NNX08A147G) United States. National Aeronautics and Space Administration (NASA Guest Investigator grant NNX07AH75G) United States. National Aeronautics and Space Administration (NASA Guest Investigator grant NNX08AJ19G) 2015-03-04T21:46:47Z 2015-03-04T21:46:47Z 2010-08 2010-05 Article http://purl.org/eprint/type/JournalArticle 0004-637X 1538-4357 http://hdl.handle.net/1721.1/95834 Isenberg, Philip A., Charles W. Smith, William H. Matthaeus, and John D. Richardson. “TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW.” The Astrophysical Journal 719, no. 1 (July 22, 2010): 716–721. © 2010 American Astronomical Society. en_US http://dx.doi.org/10.1088/0004-637x/719/1/716 Astrophysical Journal Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf Institute of Physics/American Astronomical Society American Astronomical Society |
| spellingShingle | Isenberg, Philip A. Smith, Charles W. Matthaeus, William H. Richardson, John D. TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW |
| title | TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW |
| title_full | TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW |
| title_fullStr | TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW |
| title_full_unstemmed | TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW |
| title_short | TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW |
| title_sort | turbulent heating of the distant solar wind by interstellar pickup protons in a decelerating flow |
| url | http://hdl.handle.net/1721.1/95834 |
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