Found 407 results
Author Title Type [ Year(Asc)]
2020
Authors: Cohen C. M. S., Christian E. R., Cummings A. C., Davis A. J., Desai M. I., et al.
Title: Energetic Particle Increases Associated with Stream Interaction Regions
Abstract:

The Parker Solar Probe was launched on 2018 August 12 and completed its second orbit on 2019 June 19 with perihelion of 35.7 solar radii. During this time, the Energetic Particle Instrument-Hi (EPI-Hi, one of the two energetic particle instruments comprising the Integrated Science Investigation of the Sun, IS☉IS) measured seven proton intensity increases associated with stream interaction regions (SIRs), two of which appear to be occurring in the same region corotating with the Sun. The events are relatively weak, with observed proton spectra extending to only a few MeV and lasting for a few days. The proton spectra are best characterized by power laws with indices ranging from −4.3 to −6.5, generally softer than events associated with SIRs observed at 1 au and beyond. Helium spec. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 20 DOI: 10.3847/1538-4365/ab4c38 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab4c38
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Authors: Joyce C. J., McComas D. J., Christian E. R., Schwadron N. A., Wiedenbeck M. E., et al.
Title: Energetic Particle Observations from the Parker Solar Probe Using Combined Energy Spectra from the IS⊙IS Instrument Suite
Abstract:

The Integrated Science Investigations of the Sun (IS☉IS) instrument suite includes two Energetic Particle instruments: EPI-Hi, designed to measure ions from ̃1 to 200 MeV nuc-1, and EPI-Lo, designed to measure ions from ̃20 to ̃15 MeV nuc-1. We present an analysis of eight energetic proton events observed across the energy range of both instruments during Parker Solar Probe’s (PSP) first two orbits in order to examine their combined energy spectra. Background corrections are applied to help resolve spectral breaks between the two instruments and are shown to be effective. In doing so we demonstrate that even in the early stages of calibration, IS☉IS is capable of producing reliable spectral observations across broad energy ranges. In addition to making gro. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 41 DOI: 10.3847/1538-4365/ab5948 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5948
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Authors: Joyce C. J., McComas D. J., Christian E. R., Schwadron N. A., Wiedenbeck M. E., et al.
Title: Energetic Particle Observations from the Parker Solar Probe Using Combined Energy Spectra from the IS⊙IS Instrument Suite
Abstract:

The Integrated Science Investigations of the Sun (IS☉IS) instrument suite includes two Energetic Particle instruments: EPI-Hi, designed to measure ions from ̃1 to 200 MeV nuc−1, and EPI-Lo, designed to measure ions from ̃20 to ̃15 MeV nuc−1. We present an analysis of eight energetic proton events observed across the energy range of both instruments during Parker Solar Probe's (PSP) first two orbits in order to examine their combined energy spectra. Background corrections are applied to help resolve spectral breaks between the two instruments and are shown to be effective. In doing so we demonstrate that even in the early stages of calibration, IS☉IS is capable of producing reliable spectral observations across broad energy ranges. In addition to making g. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 41 DOI: 10.3847/1538-4365/ab5948 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5948
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Authors: Bandyopadhyay Riddhi, Goldstein M. L., Maruca B. A., Matthaeus W. H., Parashar T. N., et al.
Title: Enhanced Energy Transfer Rate in Solar Wind Turbulence Observed near the Sun from Parker Solar Probe
Abstract:

Direct evidence of an inertial-range turbulent energy cascade has been provided by spacecraft observations in heliospheric plasmas. In the solar wind, the average value of the derived heating rate near 1 au is \~10 3 Jkg -1 s -1  \~103Jkg-1s-1 , an amount sufficient to account for observed departures from adiabatic expansion. Parker Solar Probe, even during its first solar encounter, offers the first opportunity to compute, in a similar fashion, a fluid-scale energy decay rate, much closer to the solar corona than any prior in situ observations. Using the Politano-Pouquet third-order law and the von Kármán decay law, we estimate the fluid-range energy transfer rate in the inner heliosphere, at heliocentric distance R ranging from 54 R (. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 48 DOI: 10.3847/1538-4365/ab5dae Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5dae
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Authors: Bandyopadhyay Riddhi, Goldstein M. L., Maruca B. A., Matthaeus W. H., Parashar T. N., et al.
Title: Enhanced Energy Transfer Rate in Solar Wind Turbulence Observed near the Sun from Parker Solar Probe
Abstract:

Direct evidence of an inertial-range turbulent energy cascade has been provided by spacecraft observations in heliospheric plasmas. In the solar wind, the average value of the derived heating rate near 1 au is ∼10 3 Jkg −1 s −1  ∼103Jkg−1s−1 , an amount sufficient to account for observed departures from adiabatic expansion. Parker Solar Probe, even during its first solar encounter, offers the first opportunity to compute, in a similar fashion, a fluid-scale energy decay rate, much closer to the solar corona than any prior in situ observations. Using the Politano─Pouquet third-order law and the von Kármán decay law, we estimate the fluid-range energy transfer rate in the inner heliosphere, at heliocentric distance R ranging from 54 RDate: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 48 DOI: 10.3847/1538-4365/ab5dae Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5dae
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Authors: Martinović Mihailo M., Klein Kristopher G., Kasper Justin C., Case Anthony W., Korreck Kelly E., et al.
Title: The Enhancement of Proton Stochastic Heating in the Near-Sun Solar Wind
Abstract:

Stochastic heating (SH) is a nonlinear heating mechanism driven by the violation of magnetic moment invariance due to large-amplitude turbulent fluctuations producing diffusion of ions toward higher kinetic energies in the direction perpendicular to the magnetic field. It is frequently invoked as a mechanism responsible for the heating of ions in the solar wind. Here, we quantify for the first time the proton SH rate Q at radial distances from the Sun as close as 0.16 au, using measurements from the first two Parker Solar Probe encounters. Our results for both the amplitude and radial trend of the heating rate, Q ∝ r−2.5, agree with previous results based on the Helios data set at heliocentric distances from 0.3 to 0.9 au. Also in agreement wit. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 30 DOI: 10.3847/1538-4365/ab527f Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab527f
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Authors: Martinović Mihailo M., Klein Kristopher G., Kasper Justin C., Case Anthony W., Korreck Kelly E., et al.
Title: The Enhancement of Proton Stochastic Heating in the Near-Sun Solar Wind
Abstract:

Stochastic heating (SH) is a nonlinear heating mechanism driven by the violation of magnetic moment invariance due to large-amplitude turbulent fluctuations producing diffusion of ions toward higher kinetic energies in the direction perpendicular to the magnetic field. It is frequently invoked as a mechanism responsible for the heating of ions in the solar wind. Here, we quantify for the first time the proton SH rate Q at radial distances from the Sun as close as 0.16 au, using measurements from the first two Parker Solar Probe encounters. Our results for both the amplitude and radial trend of the heating rate, Q ∝ r-2.5, agree with previous results based on the Helios data set at heliocentric distances from 0.3 to 0.9 au. Also in agreement with . . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 30 DOI: 10.3847/1538-4365/ab527f Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab527f
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Authors: Chen C. H. K., Bale S. D., Bonnell J. W., Borovikov D., Bowen T. A., et al.
Title: The Evolution and Role of Solar Wind Turbulence in the Inner Heliosphere
Abstract:

The first two orbits of the Parker Solar Probe spacecraft have enabled the first in situ measurements of the solar wind down to a heliocentric distance of 0.17 au (or 36 R ⊙  R⊙ ). Here, we present an analysis of this data to study solar wind turbulence at 0.17 au and its evolution out to 1 au. While many features remain similar, key differences at 0.17 au include increased turbulence energy levels by more than an order of magnitude, a magnetic field spectral index of -3/2 matching that of the velocity and both Elsasser fields, a lower magnetic compressibility consistent with a smaller slow-mode kinetic energy fraction, and a much smaller outer scale that has had time for substantial nonlinear processing. There is also an overall increase in the dominance of . . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 53 DOI: 10.3847/1538-4365/ab60a3 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab60a3
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Authors: Chen C. H. K., Bale S. D., Bonnell J. W., Borovikov D., Bowen T. A., et al.
Title: The Evolution and Role of Solar Wind Turbulence in the Inner Heliosphere
Abstract:

The first two orbits of the Parker Solar Probe spacecraft have enabled the first in situ measurements of the solar wind down to a heliocentric distance of 0.17 au (or 36 R ⊙  R⊙ ). Here, we present an analysis of this data to study solar wind turbulence at 0.17 au and its evolution out to 1 au. While many features remain similar, key differences at 0.17 au include increased turbulence energy levels by more than an order of magnitude, a magnetic field spectral index of −3/2 matching that of the velocity and both Elsasser fields, a lower magnetic compressibility consistent with a smaller slow-mode kinetic energy fraction, and a much smaller outer scale that has had time for substantial nonlinear processing. There is also an overall increase in the dominance o. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 53 DOI: 10.3847/1538-4365/ab60a3 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab60a3
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Authors: Macneil Allan R, Owens Mathew J, Wicks Robert T, Lockwood Mike, Bentley Sarah N, et al.
Title: The evolution of inverted magnetic fields through the inner heliosphereABSTRACT
Abstract:

Local inversions are often observed in the heliospheric magnetic field (HMF), but their origins and evolution are not yet fully understood. Parker Solar Probe has recently observed rapid, Alfvénic, HMF inversions in the inner heliosphere, known as 'switchbacks', which have been interpreted as the possible remnants of coronal jets. It has also been suggested that inverted HMF may be produced by near-Sun interchange reconnection; a key process in mechanisms proposed for slow solar wind release. These cases suggest that the source of inverted HMF is near the Sun, and it follows that these inversions would gradually decay and straighten as they propagate out through the heliosphere. Alternatively, HMF inversions could form during solar wind transit, through phenomena such velocity shears, . . .
Date: 04-2020 Publisher: Monthly Notices of the Royal Astronomical Society Pages: 3642 - 3655 DOI: 10.1093/mnras/staa951 Available at: https://academic.oup.com/mnras/article/494/3/3642/5819029
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Authors: Macneil Allan R, Owens Mathew J, Wicks Robert T, Lockwood Mike, Bentley Sarah N, et al.
Title: The evolution of inverted magnetic fields through the inner heliosphereABSTRACT
Abstract:

Local inversions are often observed in the heliospheric magnetic field (HMF), but their origins and evolution are not yet fully understood. Parker Solar Probe has recently observed rapid, Alfvénic, HMF inversions in the inner heliosphere, known as ’switchbacks’, which have been interpreted as the possible remnants of coronal jets. It has also been suggested that inverted HMF may be produced by near-Sun interchange reconnection; a key process in mechanisms proposed for slow solar wind release. These cases suggest that the source of inverted HMF is near the Sun, and it follows that these inversions would gradually decay and straighten as they propagate out through the heliosphere. Alternatively, HMF inversions could form during solar wind transit, through phenomena such velocity shea. . .
Date: 04-2020 Publisher: Monthly Notices of the Royal Astronomical Society Pages: 3642 - 3655 DOI: 10.1093/mnras/staa951 Available at: https://academic.oup.com/mnras/article/494/3/3642/5819029
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Authors: Page Brent, Bale Stuart D., Bonnell J. W., Goetz Keith, Goodrich Katherine, et al.
Title: Examining Dust Directionality with the Parker Solar Probe FIELDS Instrument
Abstract:

Parker Solar Probe’s (PSP’s) FIELDS instrument provides a measure of the dust impact rate on the spacecraft with a full-coverage summary of the voltages recorded by the spacecraft’s antennas. From consecutively sampled periods throughout PSP’s orbit, FIELDS stores the maximum amplitude measured by each active antenna. The occurrence of a dust impact during a given period can be identified by these amplitudes exceeding a few tens of millivolts, and a dust grain’s impact location can be approximated using the differential amplitudes between antennas. The impact locations indicated in the data are inspected for compatibility with the incident directions of prograde, retrograde, and β-meteoroid orbits in the ecliptic. Important features in the data are consistent with the inciden. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 51 DOI: 10.3847/1538-4365/ab5f6a Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5f6a
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Authors: Page Brent, Bale Stuart D., Bonnell J. W., Goetz Keith, Goodrich Katherine, et al.
Title: Examining Dust Directionality with the Parker Solar Probe FIELDS Instrument
Abstract:

Parker Solar Probe's (PSP's) FIELDS instrument provides a measure of the dust impact rate on the spacecraft with a full-coverage summary of the voltages recorded by the spacecraft's antennas. From consecutively sampled periods throughout PSP's orbit, FIELDS stores the maximum amplitude measured by each active antenna. The occurrence of a dust impact during a given period can be identified by these amplitudes exceeding a few tens of millivolts, and a dust grain's impact location can be approximated using the differential amplitudes between antennas. The impact locations indicated in the data are inspected for compatibility with the incident directions of prograde, retrograde, and β-meteoroid orbits in the ecliptic. Important features in the data are consistent with the incidence of β-m. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 51 DOI: 10.3847/1538-4365/ab5f6a Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5f6a
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Authors: Panasenco Olga, Velli Marco, D’Amicis Raffaella, Shi Chen, Réville Victor, et al.
Title: Exploring Solar Wind Origins and Connecting Plasma Flows from the Parker Solar Probe to 1 au: Nonspherical Source Surface and Alfvénic Fluctuations
Abstract:

The magnetic field measurements of the FIELDS instrument on the Parker Solar Probe (PSP) have shown intensities, throughout its first solar encounter, that require a very low source surface (SS) height ( R SS ⩽1.8R ⊙  RSS⩽1.8R⊙ ) to be reconciled with magnetic field measurements at the Sun via potential field extrapolation (PFSS). However, during PSP's second encounter, the situation went back to a more classic SS height ( R SS ⩽2.5R ⊙  RSS⩽2.5R⊙ ). Here we use high-resolution observations of the photospheric magnetic field (Solar Dynamics Observatory/Helioseismic and Magnetic Imager) to calculate neutral lines and boundaries of the open field regions for SS heights from 1.2 to 2.5 RDate: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 54 DOI: 10.3847/1538-4365/ab61f4 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab61f4
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Authors: Panasenco Olga, Velli Marco, D’Amicis Raffaella, Shi Chen, Réville Victor, et al.
Title: Exploring Solar Wind Origins and Connecting Plasma Flows from the Parker Solar Probe to 1 au: Nonspherical Source Surface and Alfvénic Fluctuations
Abstract:

The magnetic field measurements of the FIELDS instrument on the Parker Solar Probe (PSP) have shown intensities, throughout its first solar encounter, that require a very low source surface (SS) height ( R SS ⩽1.8R ⊙  RSS⩽1.8R⊙ ) to be reconciled with magnetic field measurements at the Sun via potential field extrapolation (PFSS). However, during PSP’s second encounter, the situation went back to a more classic SS height ( R SS ⩽2.5R ⊙  RSS⩽2.5R⊙ ). Here we use high-resolution observations of the photospheric magnetic field (Solar Dynamics Observatory/Helioseismic and Magnetic Imager) to calculate neutral lines and boundaries of the open field regions for SS heights from 1.2 to 2.5 R<. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 54 DOI: 10.3847/1538-4365/ab61f4 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab61f4
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Authors: Parker Eugene N.
Title: Exploring the innermost solar atmosphere
Abstract:

The Parker Solar Probe spacecraft completed the first two of its 24 scheduled orbits around the Sun on 18 June 2019, making history by flying halfway between Mercury and the Sun.


Date: 01/2020 Publisher: Nature Astronomy Pages: 19 - 20 DOI: 10.1038/s41550-019-0985-7 Available at: http://www.nature.com/articles/s41550-019-0985-7
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Authors: Parker Eugene N.
Title: Exploring the innermost solar atmosphere
Abstract:

The Parker Solar Probe spacecraft completed the first two of its 24 scheduled orbits around the Sun on 18 June 2019, making history by flying halfway between Mercury and the Sun.


Date: 01/2020 Publisher: Nature Astronomy Pages: 19 - 20 DOI: 10.1038/s41550-019-0985-7 Available at: http://www.nature.com/articles/s41550-019-0985-7
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Authors: Moncuquet Michel, Meyer-Vernet Nicole, Issautier Karine, Pulupa Marc, Bonnell J. W., et al.
Title: First In Situ Measurements of Electron Density and Temperature from Quasi-thermal Noise Spectroscopy with Parker Solar Probe /FIELDS
Abstract:

Heat transport in the solar corona and wind is still a major unsolved astrophysical problem. Because of the key role played by electrons, the electron density and temperature(s) are important prerequisites for understanding these plasmas. We present such in situ measurements along the two first solar encounters of the Parker Solar Probe, between 0.5 and 0.17 au from the Sun, revealing different states of the emerging solar wind near the solar activity minimum. These preliminary results are obtained from a simplified analysis of the plasma quasi-thermal noise (QTN) spectrum measured by the Radio Frequency Spectrometer (FIELDS). The local electron density is deduced from the tracking of the plasma line, which enables accurate measurements, independent of calibrations and spacecraft pertur. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 44 DOI: 10.3847/1538-4365/ab5a84 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5a84
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Authors: Moncuquet Michel, Meyer-Vernet Nicole, Issautier Karine, Pulupa Marc, Bonnell J. W., et al.
Title: First In Situ Measurements of Electron Density and Temperature from Quasi-thermal Noise Spectroscopy with Parker Solar Probe /FIELDS
Abstract:

Heat transport in the solar corona and wind is still a major unsolved astrophysical problem. Because of the key role played by electrons, the electron density and temperature(s) are important prerequisites for understanding these plasmas. We present such in situ measurements along the two first solar encounters of the Parker Solar Probe, between 0.5 and 0.17 au from the Sun, revealing different states of the emerging solar wind near the solar activity minimum. These preliminary results are obtained from a simplified analysis of the plasma quasi-thermal noise (QTN) spectrum measured by the Radio Frequency Spectrometer (FIELDS). The local electron density is deduced from the tracking of the plasma line, which enables accurate measurements, independent of calibrations and spacecraft pertur. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 44 DOI: 10.3847/1538-4365/ab5a84 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab5a84
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Authors: Mondal Surajit, Oberoi Divya, and Mohan Atul
Title: First Radio Evidence for Impulsive Heating Contribution to the Quiet Solar Corona
Abstract:

This Letter explores the relevance of nanoflare-based models for heating the quiet Sun corona. Using meterwave data from the Murchison Widefield Array, we present the first successful detection of impulsive emissions down to flux densities of ∼mSFU, about two orders of magnitude weaker than earlier attempts. These impulsive emissions have durations ≲1 s and are present throughout the quiet solar corona. The fractional time occupancy of these impulsive emissions at a given region is ≲10%. The histograms of these impulsive emissions follow a power-law distribution and show signs of clustering at small timescales. Our estimate of the energy that must be dumped in the corona to generate these impulsive emissions is consistent with the coronal heating requirements. Additionally, the st. . .
Date: 06/2020 Publisher: The Astrophysical Journal Pages: L39 DOI: 10.3847/2041-8213/ab8817 Available at: https://iopscience.iop.org/article/10.3847/2041-8213/ab8817https://iopscience.iop.org/article/10.3847/2041-8213/ab8817/
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Authors: Mondal Surajit, Oberoi Divya, and Mohan Atul
Title: First Radio Evidence for Impulsive Heating Contribution to the Quiet Solar Corona
Abstract:

This Letter explores the relevance of nanoflare-based models for heating the quiet Sun corona. Using meterwave data from the Murchison Widefield Array, we present the first successful detection of impulsive emissions down to flux densities of \~mSFU, about two orders of magnitude weaker than earlier attempts. These impulsive emissions have durations ≲1 s and are present throughout the quiet solar corona. The fractional time occupancy of these impulsive emissions at a given region is ≲10%. The histograms of these impulsive emissions follow a power-law distribution and show signs of clustering at small timescales. Our estimate of the energy that must be dumped in the corona to generate these impulsive emissions is consistent with the coronal heating requirements. Additionally, the sta. . .
Date: 06/2020 Publisher: The Astrophysical Journal Pages: L39 DOI: 10.3847/2041-8213/ab8817 Available at: https://iopscience.iop.org/article/10.3847/2041-8213/ab8817https://iopscience.iop.org/article/10.3847/2041-8213/ab8817/
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Authors: Fisk L. A., and Kasper J. C.
Title: Global Circulation of the Open Magnetic Flux of the Sun
Abstract:

The global circulation of the open magnetic flux of the Sun, the component of the solar magnetic field that opens into the heliosphere, and the consequences of the global circulation were proposed by Fisk and coworkers in the early 2000s. The Parker Solar Probe, on its initial encounters with the Sun, has provided direct confirmation of both the global circulation and the physical mechanism by which the circulation occurs, transport by interchange reconnection between open magnetic flux and large coronal loops. The implications of this confirmation of the global circulation of open magnetic flux and the importance of interchange reconnection is discussed.


Date: 05/2020 Publisher: The Astrophysical Journal Pages: L4 DOI: 10.3847/2041-8213/ab8acd Available at: https://iopscience.iop.org/article/10.3847/2041-8213/ab8acd
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Authors: Fisk L. A., and Kasper J. C.
Title: Global Circulation of the Open Magnetic Flux of the Sun
Abstract:

The global circulation of the open magnetic flux of the Sun, the component of the solar magnetic field that opens into the heliosphere, and the consequences of the global circulation were proposed by Fisk and coworkers in the early 2000s. The Parker Solar Probe, on its initial encounters with the Sun, has provided direct confirmation of both the global circulation and the physical mechanism by which the circulation occurs, transport by interchange reconnection between open magnetic flux and large coronal loops. The implications of this confirmation of the global circulation of open magnetic flux and the importance of interchange reconnection is discussed.


Date: 05/2020 Publisher: The Astrophysical Journal Pages: L4 DOI: 10.3847/2041-8213/ab8acd Available at: https://iopscience.iop.org/article/10.3847/2041-8213/ab8acd
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Authors: Lavraud B., Fargette N., Réville V., Szabo A., Huang J., et al.
Title: The Heliospheric Current Sheet and Plasma Sheet during Parker Solar Probe’s First Orbit
Abstract:

We present heliospheric current sheet (HCS) and plasma sheet (HPS) observations during Parker Solar Probe's (PSP) first orbit around the Sun. We focus on the eight intervals that display a true sector boundary (TSB; based on suprathermal electron pitch angle distributions) with one or several associated current sheets. The analysis shows that (1) the main density enhancements in the vicinity of the TSB and HCS are typically associated with electron strahl dropouts, implying magnetic disconnection from the Sun, (2) the density enhancements are just about twice that in the surrounding regions, suggesting mixing of plasmas from each side of the HCS, (3) the velocity changes at the main boundaries are either correlated or anticorrelated with magnetic field changes, consistent with magnetic . . .
Date: 05/2020 Publisher: The Astrophysical Journal Pages: L19 DOI: 10.3847/2041-8213/ab8d2d Available at: https://iopscience.iop.org/article/10.3847/2041-8213/ab8d2d
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Authors: Lavraud B., Fargette N., Réville V., Szabo A., Huang J., et al.
Title: The Heliospheric Current Sheet and Plasma Sheet during Parker Solar Probe’s First Orbit
Abstract:

We present heliospheric current sheet (HCS) and plasma sheet (HPS) observations during Parker Solar Probe’s (PSP) first orbit around the Sun. We focus on the eight intervals that display a true sector boundary (TSB; based on suprathermal electron pitch angle distributions) with one or several associated current sheets. The analysis shows that (1) the main density enhancements in the vicinity of the TSB and HCS are typically associated with electron strahl dropouts, implying magnetic disconnection from the Sun, (2) the density enhancements are just about twice that in the surrounding regions, suggesting mixing of plasmas from each side of the HCS, (3) the velocity changes at the main boundaries are either correlated or anticorrelated with magnetic field changes, consistent with magneti. . .
Date: 05/2020 Publisher: The Astrophysical Journal Pages: L19 DOI: 10.3847/2041-8213/ab8d2d Available at: https://iopscience.iop.org/article/10.3847/2041-8213/ab8d2d
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