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Authors: Wu Honghong, Verscharen Daniel, Wicks Robert T., Chen Christopher H. K., He Jiansen, et al.
Title: The Fluid-like and Kinetic Behavior of Kinetic Alfvén Turbulence in Space Plasma
Abstract:

Kinetic Alfvén waves (KAWs) are the short-wavelength extension of the magnetohydrodynamics Alfvén-wave branch in the case of highly oblique propagation with respect to the background magnetic field. Observations of space plasma show that small-scale turbulence is mainly KAW-like. We apply two theoretical approaches, a collisional two-fluid theory and a collisionless linear kinetic theory, to obtain predictions for the KAW polarizations depending on β p (the ratio of the proton thermal pressure to the magnetic pressure) at the ion gyroscale in terms of fluctuations in density, bulk velocity, and pressure. We perform a wavelet analysis of Magnetospheric Multiscale magnetosheath measurements and compare the observations with both the. . .
Date: 01/2019 Publisher: The Astrophysical Journal Pages: 106 DOI: 10.3847/1538-4357/aaef77 Available at: http://stacks.iop.org/0004-637X/870/i=2/a=106?key=crossref.82a2db48f1fad21f326ef5e3fb4b795
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Authors: Wu Honghong, Verscharen Daniel, Wicks Robert T., Chen Christopher H. K., He Jiansen, et al.
Title: The Fluid-like and Kinetic Behavior of Kinetic Alfvén Turbulence in Space Plasma
Abstract:

Kinetic Alfvén waves (KAWs) are the short-wavelength extension of the magnetohydrodynamics Alfvén-wave branch in the case of highly oblique propagation with respect to the background magnetic field. Observations of space plasma show that small-scale turbulence is mainly KAW-like. We apply two theoretical approaches, a collisional two-fluid theory and a collisionless linear kinetic theory, to obtain predictions for the KAW polarizations depending on β p (the ratio of the proton thermal pressure to the magnetic pressure) at the ion gyroscale in terms of fluctuations in density, bulk velocity, and pressure. We perform a wavelet analysis of Magnetospheric Multiscale magnetosheath measurements and compare the observations with both the. . .
Date: 01/2019 Publisher: The Astrophysical Journal Pages: 106 DOI: 10.3847/1538-4357/aaef77 Available at: http://stacks.iop.org/0004-637X/870/i=2/a=106?key=crossref.82a2db48f1fad21f326ef5e3fb4b795
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Authors: Wood Brian E., Hess Phillip, Howard Russell A., Stenborg Guillermo, and Wang Yi-Ming
Title: Morphological Reconstruction of a Small Transient Observed by Parker Solar Probe on 2018 November 5
Abstract:

On 2018 November 5, about 24 hr before the first close perihelion passage of Parker Solar Probe (PSP), a coronal mass ejection (CME) entered the field of view of the inner detector of the Wide-field Imager for Solar PRobe (WISPR) instrument on board PSP, with the northward component of its trajectory carrying the leading edge of the CME off the top edge of the detector about four hours after its first appearance. We connect this event to a very small jetlike transient observed from 1 au by coronagraphs on both the SOlar and Heliospheric Observatory (SOHO) and the A component of the Solar TErrestrial RElations Observatory mission (STEREO-A). This allows us to make the first three-dimensional reconstruction of a CME structure considering both observations made very close to the Sun and im. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 28 DOI: 10.3847/1538-4365/ab5219 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5219
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Authors: Wood Brian E., Hess Phillip, Howard Russell A., Stenborg Guillermo, and Wang Yi-Ming
Title: Morphological Reconstruction of a Small Transient Observed by Parker Solar Probe on 2018 November 5
Abstract:

On 2018 November 5, about 24 hr before the first close perihelion passage of Parker Solar Probe (PSP), a coronal mass ejection (CME) entered the field of view of the inner detector of the Wide-field Imager for Solar PRobe (WISPR) instrument on board PSP, with the northward component of its trajectory carrying the leading edge of the CME off the top edge of the detector about four hours after its first appearance. We connect this event to a very small jetlike transient observed from 1 au by coronagraphs on both the SOlar and Heliospheric Observatory (SOHO) and the A component of the Solar TErrestrial RElations Observatory mission (STEREO-A). This allows us to make the first three-dimensional reconstruction of a CME structure considering both observations made very close to the Sun and im. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 28 DOI: 10.3847/1538-4365/ab5219 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5219
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Authors: Witze Alexandra
Title: Death-defying NASA mission will make humanity’s closest approach to the Sun
Abstract:

The Parker Solar Probe will dive into the sizzling solar corona to explore its mysteries.


Date: 07/2018 Publisher: Nature Pages: 452 - 453 DOI: 10.1038/d41586-018-05741-6 Available at: http://www.nature.com/articles/d41586-018-05741-6http://www.nature.com/articles/d41586-018-05741-6.pdfhttp://www.nature.com/articles/d41586-018-05741-6http://www.nature.com/articles/d41586-018-05741-6.pdf
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Authors: Witze Alexandra
Title: Death-defying NASA mission will make humanity’s closest approach to the Sun
Abstract:

The Parker Solar Probe will dive into the sizzling solar corona to explore its mysteries.


Date: 07/2018 Publisher: Nature Pages: 452 - 453 DOI: 10.1038/d41586-018-05741-6 Available at: http://www.nature.com/articles/d41586-018-05741-6http://www.nature.com/articles/d41586-018-05741-6.pdfhttp://www.nature.com/articles/d41586-018-05741-6http://www.nature.com/articles/d41586-018-05741-6.pdf
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Authors: Witze Alexandra
Title: Sun-bombing spacecraft uncovers secrets of the solar wind
Abstract:

Surprise magnetic reversals and an unexpectedly fast rotating wind mark the first findings from NASA's Parker Solar Probe.


Date: 12/2019 Publisher: Nature Pages: 15 - 16 DOI: 10.1038/d41586-019-03684-0 Available at: http://www.nature.com/articles/d41586-019-03684-0http://www.nature.com/articles/d41586-019-03684-0.pdfhttp://www.nature.com/articles/d41586-019-03684-0.pdfhttp://www.nature.com/articles/d41586-019-03684-0
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Authors: Witze Alexandra
Title: Sun-bombing spacecraft uncovers secrets of the solar wind
Abstract:

Surprise magnetic reversals and an unexpectedly fast rotating wind mark the first findings from NASA’s Parker Solar Probe.


Date: 12/2019 Publisher: Nature Pages: 15 - 16 DOI: 10.1038/d41586-019-03684-0 Available at: http://www.nature.com/articles/d41586-019-03684-0http://www.nature.com/articles/d41586-019-03684-0.pdfhttp://www.nature.com/articles/d41586-019-03684-0.pdfhttp://www.nature.com/articles/d41586-019-03684-0
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Authors: Winslow Reka M., Schwadron Nathan A., Lugaz é, Guo Jingnan, Joyce Colin J., et al.
Title: Opening a Window on ICME-driven GCR Modulation in the Inner Solar System
Abstract:

Interplanetary coronal mass ejections (ICMEs) often cause Forbush decreases (Fds) in the flux of galactic cosmic rays (GCRs). We investigate how a single ICME, launched from the Sun on 2014 February 12, affected GCR fluxes at Mercury, Earth, and Mars. We use GCR observations from MESSENGER at Mercury, ACE/LRO at the Earth/Moon, and MSL at Mars. We find that Fds are steeper and deeper closer to the Sun, and that the magnitude of the magnetic field in the ICME magnetic ejecta as well as the “strength” of the ICME sheath both play a large role in modulating the depth of the Fd. Based on our results, we hypothesize that (1) the Fd size decreases exponentially with heliocentric distance, and (2) that two-step Fds are more common closer to the Sun. Both hypotheses will be directly verifia. . .
Date: 04/2018 Publisher: The Astrophysical Journal Pages: 139 DOI: 10.3847/1538-4357/aab098 Available at: http://stacks.iop.org/0004-637X/856/i=2/a=139?key=crossref.287f3cbc519cdfae455bd8b9d0a9351a
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Authors: Winslow Reka M., Schwadron Nathan A., Lugaz é, Guo Jingnan, Joyce Colin J., et al.
Title: Opening a Window on ICME-driven GCR Modulation in the Inner Solar System
Abstract:

Interplanetary coronal mass ejections (ICMEs) often cause Forbush decreases (Fds) in the flux of galactic cosmic rays (GCRs). We investigate how a single ICME, launched from the Sun on 2014 February 12, affected GCR fluxes at Mercury, Earth, and Mars. We use GCR observations from MESSENGER at Mercury, ACE/LRO at the Earth/Moon, and MSL at Mars. We find that Fds are steeper and deeper closer to the Sun, and that the magnitude of the magnetic field in the ICME magnetic ejecta as well as the “strength” of the ICME sheath both play a large role in modulating the depth of the Fd. Based on our results, we hypothesize that (1) the Fd size decreases exponentially with heliocentric distance, and (2) that two-step Fds are more common closer to the Sun. Both hypotheses will be directly verifia. . .
Date: 04/2018 Publisher: The Astrophysical Journal Pages: 139 DOI: 10.3847/1538-4357/aab098 Available at: http://stacks.iop.org/0004-637X/856/i=2/a=139?key=crossref.287f3cbc519cdfae455bd8b9d0a9351a
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Authors: Wilson Lynn B., Chen Li-Jen, Wang Shan, Schwartz Steven J., Turner Drew L., et al.
Title: Electron Energy Partition across Interplanetary Shocks. II. Statistics
Abstract:

A statistical analysis of 15,210 electron velocity distribution function (VDF) fits, observed within ±2 hr of 52 interplanetary (IP) shocks by the Wind spacecraft near 1 au, is presented. This is the second in a three-part series on electron VDFs near IP shocks. The electron velocity moment statistics for the dense, low-energy core, tenuous, hot halo, and field-aligned beam/strahl are a statistically significant list of values illustrated with both histograms and tabular lists for reference and baselines in future work. Given the large statistics in this investigation, the beam/strahl fit results in the upstream are now the most comprehensive attempt to parameterize the beam/strahl electron velocity moments in the ambient solar wind. The median density, temperature, beta, and temperatu. . .
Date: 12/2019 Publisher: The Astrophysical Journal Supplement Series Pages: 24 DOI: 10.3847/1538-4365/ab5445 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5445
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Authors: Wiedenbeck M. E., Angold N. G., Birdwell B., Burnham J. A., Christian E. R., et al.
Title: Capabilities and Performance of the High-Energy Energetic-Particles Instrument for the Parker Solar Probe Mission
Abstract:

NASA’s Parker Solar Probe (PSP) spacecraft (formerly Solar Probe Plus) is scheduled for launch in July 2018 with a planned heliocentric orbit that will carry it on a series of close passes by the Sun with perihelion distances that eventually will get below 10 solar radii. Among other in-situ and imaging sensors, the PSP payload includes the two-instrument “Integrated Science Investigation of the Sun” suite, which will make coordinated measurements of energetic ions and electrons. The high-energy instrument (EPI-Hi), operating in the MeV energy range, consists of three detector-telescopes using silicon solid-state sensors for measuring composition, energy spectra, angular distributions, and time structure in solar energetic particle events. The expected performance of this instrume. . .
Date: 10/2017 Publisher: Sissa Medialab DOI: 10.22323/1.301.0016 Available at: https://pos.sissa.it/301/016
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Authors: Wiedenbeck M. E., Bučík R., Mason G. M., Ho G. C., Leske R. A., et al.
Title: 3 He-rich Solar Energetic Particle Observations at the Parker Solar Probe and near Earth
Abstract:

The Integrated Science Investigation of the Sun (IS☉IS) instrument suite on the Parker Solar Probe (PSP) spacecraft is making in situ observations of energetic ions and electrons closer to the Sun than any previous mission. Using data collected during its first two orbits, which reached perihelion distances of 0.17 au, we have searched for  3 He 3He -rich solar energetic particle (SEP) events under very quiet solar minimum conditions. On 2019-110-111 (April 20-21),  3 He 3He -rich SEPs were observed at energies near 1 MeV nucleon-1 in association with energetic protons, heavy ions, and electrons. This activity was also detected by the Ultra-Low-Energy Isotope Spectrometer and the Electron, Proton, and Alpha Monitor instruments on the Advanced C. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 42 DOI: 10.3847/1538-4365/ab5963 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5963
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Authors: Wiedenbeck M. E., Bučík R., Mason G. M., Ho G. C., Leske R. A., et al.
Title: 3 He-rich Solar Energetic Particle Observations at the Parker Solar Probe and near Earth
Abstract:

The Integrated Science Investigation of the Sun (IS☉IS) instrument suite on the Parker Solar Probe (PSP) spacecraft is making in situ observations of energetic ions and electrons closer to the Sun than any previous mission. Using data collected during its first two orbits, which reached perihelion distances of 0.17 au, we have searched for  3 He 3He -rich solar energetic particle (SEP) events under very quiet solar minimum conditions. On 2019-110─111 (April 20─21),  3 He 3He -rich SEPs were observed at energies near 1 MeV nucleon─1 in association with energetic protons, heavy ions, and electrons. This activity was also detected by the Ultra-Low-Energy Isotope Spectrometer and the Electron, Proton, and Alpha Monitor instruments on the Adva. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 42 DOI: 10.3847/1538-4365/ab5963 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5963
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Authors: Wicks Robert T., Matteini Lorenzo, Horbury Timothy S., Hellinger Petr, and Roberts Aaron
Title: AIP Conference ProceedingsTemperature anisotropy instabilities; combining plasma and magnetic field data at different distances from the Sun
Abstract:

We present a new data analysis method enabling the observation of magnetic field fluctuations associated with temperature anisotropy instabilities using the Ulysses spacecraft. The movement of the spacecraft away from the Sun causes the observed plasma conditions, turbulent fluctuation amplitude, magnetic field strength and important physical scales to change. We normalize wavelet power spectra of the magnetic field using local values for the proton gyroscale and large scale magnetic field fluctuation amplitude to remove the effects of varying heliocentric distance. We recover the enhancement of magnetic fluctuations where temperature anisotropy instability growth rates are large, as seen by previous studies in the ecliptic at 1 AU. This method can be applied to any spacecraft data that. . .
Date: 07/2013 Publisher: AIP DOI: 10.1063/1.4811048 Available at: http://aip.scitation.org/doi/abs/10.1063/1.4811048
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Authors: Wicks Robert T., Matteini Lorenzo, Horbury Timothy S., Hellinger Petr, and Roberts Aaron
Title: AIP Conference ProceedingsTemperature anisotropy instabilities; combining plasma and magnetic field data at different distances from the Sun
Abstract:

We present a new data analysis method enabling the observation of magnetic field fluctuations associated with temperature anisotropy instabilities using the Ulysses spacecraft. The movement of the spacecraft away from the Sun causes the observed plasma conditions, turbulent fluctuation amplitude, magnetic field strength and important physical scales to change. We normalize wavelet power spectra of the magnetic field using local values for the proton gyroscale and large scale magnetic field fluctuation amplitude to remove the effects of varying heliocentric distance. We recover the enhancement of magnetic fluctuations where temperature anisotropy instability growth rates are large, as seen by previous studies in the ecliptic at 1 AU. This method can be applied to any spacecraft data that. . .
Date: 07/2013 Publisher: AIP DOI: 10.1063/1.4811048 Available at: http://aip.scitation.org/doi/abs/10.1063/1.4811048
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Authors: Whittlesey Phyllis L., Larson Davin E., Kasper Justin C., Halekas Jasper, Abatcha Mamuda, et al.
Title: The Solar Probe ANalyzers—Electrons on the Parker Solar Probe
Abstract:

Electrostatic analyzers of different designs have been used since the earliest days of the space age, beginning with the very earliest solar-wind measurements made by Mariner 2 en route to Venus in 1962. The Parker Solar Probe (PSP) mission, NASA’s first dedicated mission to study the innermost reaches of the heliosphere, makes its thermal plasma measurements using a suite of instruments called the Solar Wind Electrons, Alphas, and Protons (SWEAP) investigation. SWEAP’s electron PSP Analyzer (Solar Probe ANalyzer-Electron (SPAN-E)) instruments are a pair of top-hat electrostatic analyzers on PSP that are capable of measuring the electron distribution function in the solar wind from 2 eV to 30 keV. For the first time, in situ measurements of thermal electrons provided by SPAN-E will . . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 74 DOI: 10.3847/1538-4365/ab7370 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab7370https://iopscience.iop.org/article/10.3847/1538-4365/ab7370/pdf
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Authors: Whittlesey Phyllis L., Larson Davin E., Kasper Justin C., Halekas Jasper, Abatcha Mamuda, et al.
Title: The Solar Probe ANalyzers—Electrons on the Parker Solar Probe
Abstract:

Electrostatic analyzers of different designs have been used since the earliest days of the space age, beginning with the very earliest solar-wind measurements made by Mariner 2 en route to Venus in 1962. The Parker Solar Probe (PSP) mission, NASA’s first dedicated mission to study the innermost reaches of the heliosphere, makes its thermal plasma measurements using a suite of instruments called the Solar Wind Electrons, Alphas, and Protons (SWEAP) investigation. SWEAP’s electron PSP Analyzer (Solar Probe ANalyzer-Electron (SPAN-E)) instruments are a pair of top-hat electrostatic analyzers on PSP that are capable of measuring the electron distribution function in the solar wind from 2 eV to 30 keV. For the first time, in situ measurements of thermal electrons provided by SPAN-E will . . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 74 DOI: 10.3847/1538-4365/ab7370 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab7370https://iopscience.iop.org/article/10.3847/1538-4365/ab7370/pdf
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