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Notice:
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Found 428 entries in the Bibliography.
Showing entries from 51 through 100
| 2021 |
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Flux Ropes, Turbulence, and Collisionless Perpendicular Shock Waves: High Plasma Beta Case With the onset of solar maximum and the expected increased prevalence of interplanetary shock waves, Parker Solar Probe is likely to observe numerous shocks in the next few years. An outstanding question that has received surprisingly little attention has been how turbulence interacts with collisionless shock waves. Turbulence in the supersonic solar wind is described frequently as a superposition of a majority 2D and a minority slab component. We formulate a collisional perpendicular shock-turbulence transmission problem in ... Zank, G.; Nakanotani, M.; Zhao, L.; Du, S.; Adhikari, L.; Che, H.; le Roux, J.; Published by: The Astrophysical Journal Published on: 06/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abf7c8 Interplanetary shocks; interplanetary turbulence; 829; 830; Parker Data Used |
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Analysis of energetic particle inner heliospheric spacecraft data increasingly suggests the existence of anomalous diffusion phenomena that should be addressed to achieve a better understanding of energetic particle transport and acceleration in the expanding solar wind medium. Related to this is fast-growing observational evidence supporting the long-standing prediction from magnetohydrodynamic (MHD) theory and simulations of the presence of an inner heliospheric, dominant quasi-two-dimensional MHD turbulence component that ... Published by: The Astrophysical Journal Published on: 06/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abf3c6 Interplanetary particle acceleration; Solar wind; Solar magnetic reconnection; 826; 1534; 1504; Parker Data Used |
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Time evolution of stream interaction region energetic particle spectra in the inner heliosphere We analyze an energetic proton event associated with a stream interaction region (SIR) that was observed at Parker Solar Probe on day 320 of 2018 when the spacecraft was just 0.34 AU from the Sun. Using the Integrated Science Investigation of the Sun instrument suite, we perform a spectral analysis of the event and show how the observed spectra evolve over the course of the event. We find that the spectra from the first day of the event are much more consistent with local acceleration at a weak compression, while spectra fro ... Joyce, C.; McComas, D.; Schwadron, N.; Christian, E.; Wiedenbeck, M.; McNutt, R.; Cohen, C.; Leske, R.; Mewaldt, R.; Stone, E.; Labrador, A.; Davis, A.; Cummings, A.; Mitchell, D.; Hill, M.; Roelof, E.; Allen, R.; Szalay, J.; Rankin, J.; Desai, M.; Giacalone, J.; Matthaeus, W.; Bale, S.; Kasper, J.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039330 acceleration of particles; Solar wind; magnetic fields; Parker Data Used |
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Energetic particle behavior in near-Sun magnetic field switchbacks from PSP Context. The observation of numerous magnetic switchbacks and associated plasma jets in Parker Solar Probe (PSP) during its first five orbits, particularly near the Sun, has attracted considerable attention. Switchbacks have been found to be systematically associated with correlated reversals in the direction of the propagation of Alfvénic fluctuations, as well as similar reversals of the electron strahl. Bandyopadhyay, R.; Matthaeus, W.; McComas, D.; Joyce, C.; Szalay, J.; Christian, E.; Giacalone, J.; Schwadron, N.; Mitchell, D.; Hill, M.; McNutt, R.; Desai, M.; Bale, S.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Harvey, P.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Kasper, J.; Stevens, M.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039800 Solar wind; magnetic fields; plasmas; turbulence; instabilities; waves; Parker Data Used |
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Context. Recent studies of the solar wind sunward of 0.25 AU reveal that it contains quiescent regions, with low-amplitude plasma and magnetic field fluctuations, and a magnetic field direction similar to the Parker spiral. The quiescent regions are thought to have a more direct magnetic connection to the solar corona than other types of solar wind, suggesting that waves or instabilities in the quiescent regions are indicative of the early evolution of the solar wind as it escapes the corona. The quiescent solar wind regions ... Malaspina, D.; Wilson, L.; Ergun, R.; Bale, S.; Bonnell, J.; Goodrich, K.; Goetz, K.; Harvey, P.; MacDowall, R.; Pulupa, M.; Halekas, J.; Case, A.; Kasper, J.; Larson, D.; Stevens, M.; Whittlesey, P.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202140449 |
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Context. Silicon solid-state detectors are commonly used for measuring the specific ionization, dE∕dx, in instruments designed for identifying energetic nuclei using the dE∕dx versus total energy technique in space and in the laboratory. The energy threshold and species resolution of the technique strongly depend on the thickness and thickness uniformity of these detectors. Wiedenbeck, M.; Burnham, J.; Cohen, C.; Cook, W.; Crabill, R.; Cummings, A.; Davis, A.; Kecman, B.; Labrador, A.; Leske, R.; Mewaldt, R.; Rankin, J.; Rusert, M.; Stone, E.; Christian, E.; Goodwin, P.; Link, J.; Nahory, B.; Shuman, S.; von Rosenvinge, T.; Tindall, C.; Black, H.; Bullough, M.; Clarke, N.; Glasson, V.; Greenwood, N.; Hawkins, C.; Johnson, T.; Newton, A.; Richardson, K.; Walsh, S.; Wilburn, C.; Birdwell, B.; Everett, d.; McComas, D.; Weidner, S.; Angold, N.; Schwadron, N.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039754 instrumentation: detectors; Sun: particle emission; acceleration of particles; space vehicles: instruments; Parker Data Used |
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Parker Solar Probe observations of He/H abundance variations in SEP events inside 0.5 au
Cohen, C.; Christian, E.; Cummings, A.; Davis, A.; Desai, M.; de Nolfo, G.; Giacalone, J.; Hill, M.; Joyce, C.; Labrador, A.; Leske, R.; Matthaeus, W.; McComas, D.; McNutt, R.; Mewaldt, R.; Mitchell, D.; Mitchell, J.; Rankin, J.; Roelof, E.; Schwadron, N.; Stone, E.; Szalay, J.; Wiedenbeck, M.; Vourlidas, A.; Bale, S.; Pulupa, M.; MacDowall, R.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039299 Sun: particle emission; Sun: activity; solar-terrestrial relations; Parker Data Used |
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Applicability of Taylor s hypothesis during Parker Solar Probe perihelia We investigate the validity of Taylor s hypothesis (TH) in the analysis of velocity and magnetic field fluctuations in Alfvénic solar wind streams measured by Parker Solar Probe (PSP) during the first four encounters. The analysis is based on a recent model of the spacetime correlation of magnetohydrodynamic (MHD) turbulence, which has been validated in high-resolution numerical simulations of strong reduced MHD turbulence. We use PSP velocity and magnetic field measurements from 24 h intervals selected from each of the fir ... Perez, Jean; Bourouaine, Sofiane; Chen, Christopher; Raouafi, Nour; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039879 Solar wind; Sun: heliosphere; turbulence; magnetohydrodynamics (MHD); plasmas; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics; Parker Data Used |
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The contribution of alpha particles to the solar wind angular momentum flux in the inner heliosphere Context. An accurate assessment of the Sun s angular momentum (AM) loss rate is an independent constraint for models that describe the rotation evolution of Sun-like stars. Finley, A.; McManus, M.; Matt, S.; Kasper, J.; Korreck, K.; Case, A.; Stevens, M.; Whittlesey, P.; Larson, D.; Livi, R.; Bale, S.; de Wit, Dudok; Goetz, K.; Harvey, P.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039288 Solar wind; stars: evolution; stars: winds; outflows; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used |
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Prevalence of magnetic reconnection in the near-Sun heliospheric current sheet During three of its first five orbits around the Sun, Parker Solar Probe (PSP) crossed the large-scale heliospheric current sheet (HCS) multiple times and provided unprecedented detailed plasma and field observations of the near-Sun HCS. We report the common detections by PSP of reconnection exhaust signatures in the HCS at heliocentric distances of 29.5-107 solar radii during encounters 1, 4, and 5. Both sunward and antisunward-directed reconnection exhausts were observed. In the sunward reconnection exhausts, PSP detected ... Phan, T.; Lavraud, B.; Halekas, J.; Øieroset, M.; Drake, J.; Eastwood, J.; Shay, M.; Pyakurel, P.; Bale, S.; Larson, D.; Livi, R.; Whittlesey, P.; Rahmati, A.; Pulupa, M.; McManus, M.; Verniero, J.; Bonnell, J.; Schwadron, N.; Stevens, M.; Case, A.; Kasper, J.; MacDowall, R.; Szabo, P.; Koval, A.; Korreck, K.; de Wit, Dudok; Malaspina, D.; Goetz, K.; Harvey, P.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039863 Sun: magnetic fields; Sun: heliosphere; Solar wind; Sun: flares; Parker Data Used |
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Detection of small magnetic flux ropes from the third and fourth Parker Solar Probe encounters Context. Zhao, L.; Zank, G.; Hu, Q.; Telloni, D.; Chen, Y.; Adhikari, L.; Nakanotani, M.; Kasper, J.; Huang, J.; Bale, S.; Korreck, K.; Case, A.; Stevens, M.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Harvey, P.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Larson, D.; Livi, R.; Whittlesey, P.; Klein, K.; Raouafi, N.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039298 Solar wind; Sun: magnetic fields; turbulence; methods: observational; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics; Parker Data Used |
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Wave-particle energy transfer directly observed in an ion cyclotron wave Context. The first studies with Parker Solar Probe (PSP) data have made significant progress toward understanding of the fundamental properties of ion cyclotron waves in the inner heliosphere. The survey mode particle measurements of PSP, however, did not make it possible to measure the coupling between electromagnetic fields and particles on the time scale of the wave periods. Vech, D.; Martinovic, M.; Klein, K.; Malaspina, D.; Bowen, T.; Verniero, J.; Paulson, K.; de Wit, Dudok; Kasper, J.; Huang, J.; Stevens, M.; Case, A.; Korreck, K.; Mozer, F.; Goodrich, K.; Bale, S.; Whittlesey, P.; Livi, R.; Larson, D.; Pulupa, M.; Bonnell, J.; Harvey, P.; Goetz, K.; MacDowall, R.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039296 Solar wind; waves; turbulence; Physics - Space Physics; Physics - Plasma Physics; Parker Data Used |
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Context. In 2020 May-June, six solar energetic ion events were observed by the Parker Solar Probe/IS⊙IS instrument suite at ≈0.35 AU from the Sun. From standard velocity-dispersion analysis, the apparent ion path length is ≈0.625 AU at the onset of each event. Chhiber, R.; Matthaeus, W.; Cohen, C.; Ruffolo, D.; Sonsrettee, W.; Tooprakai, P.; Seripienlert, A.; Chuychai, P.; Usmanov, A.; Goldstein, M.; McComas, D.; Leske, R.; Christian, E.; Mewaldt, R.; Labrador, A.; al., et; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: "10.1051/0004-6361/202039816" |
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Jagarlamudi, V.; de Wit, Dudok; Froment, C.; Krasnoselskikh, V.; Larosa, A.; Bercic, L.; Agapitov, O.; Halekas, J.; Kretzschmar, M.; Malaspina, D.; Moncuquet, M.; Bale, S.; Case, A.; Kasper, J.; Korreck, K.; Larson, D.; Pulupa, M.; Stevens, M.; Whittlesey, P.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039808 waves; scattering; plasmas; Sun: heliosphere; magnetic fields; Physics - Space Physics; Parker Data Used |
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Alfvenic versus non-Alfvenic turbulence in the inner heliosphere as observed by Parker Solar Probe Context. Parker Solar Probe (PSP) measures the magnetic field and plasma parameters of the solar wind at unprecedentedly close distances to the Sun. These data provide great opportunities to study the early-stage evolution of magnetohydrodynamic (MHD) turbulence in the solar wind. Shi, C.; Velli, M.; Panasenco, O.; Tenerani, A.; eville, V.; Bale, S.; Kasper, J.; Korreck, K.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Harvey, P.; MacDowall, R.; Pulupa, M.; Case, A.; Larson, D.; Verniero, J.; Livi, R.; Stevens, M.; al., et; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: "10.1051/0004-6361/202039818" |
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The active region source of a type III radio storm observed by Parker Solar Probe during encounter 2 Context. We investigated the source of a type III radio burst storm during encounter 2 of NASA s Parker Solar Probe (PSP) mission. Harra, L.; Brooks, D.; Bale, S.; Mandrini, C.; Barczynski, K.; Sharma, R.; Badman, S.; Domínguez, Vargas; Pulupa, M.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039514 Sun: corona; Solar wind; Sun: radio radiation; Sun: abundances; Sun: atmosphere; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics; Parker Data Used |
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Context. Periodicities have frequently been reported across many wavelengths in the solar corona. Correlated periods of ~5 min, comparable to solar p-modes, are suggestive of coupling between the photosphere and the corona. Cattell, Cynthia; Glesener, Lindsay; Leiran, Benjamin; Dombeck, John; Goetz, Keith; Oliveros, Juan; Badman, Samuel; Pulupa, Marc; Bale, Stuart; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039510 Sun: radio radiation; Sun: corona; Sun: X-rays; gamma rays; Sun: oscillations; magnetic reconnection; radiation mechanisms: non-thermal; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics; Parker Data Used |
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Context. The first encounters of Parker Solar Probe (PSP) with the Sun revealed the presence of ubiquitous localised magnetic deflections in the inner heliosphere; these structures, often called switchbacks, are particularly striking in solar wind streams originating from coronal holes. Froment, C.; Krasnoselskikh, V.; de Wit, Dudok; Agapitov, O.; Fargette, N.; Lavraud, B.; Larosa, A.; Kretzschmar, M.; Jagarlamudi, V.; Velli, M.; Malaspina, D.; Whittlesey, P.; Bale, S.; Case, A.; Goetz, K.; Kasper, J.; Korreck, K.; Larson, D.; MacDowall, R.; Mozer, F.; Pulupa, M.; Revillet, C.; Stevens, M.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039806 Sun: heliosphere; Solar wind; magnetic fields; magnetic reconnection; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics; Parker Data Used |
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Switchbacks: statistical properties and deviations from Alfvénicity Context. Parker Solar Probe s first solar encounter has revealed the presence of sudden magnetic field deflections in the slow Alfvénic solar wind. These structures, which are often called switchbacks, are associated with proton velocity enhancements. Larosa, A.; Krasnoselskikh, V.; de Wit, Dudok; Agapitov, O.; Froment, C.; Jagarlamudi, V.; Velli, M.; Bale, S.; Case, A.; Goetz, K.; Harvey, P.; Kasper, J.; Korreck, K.; Larson, D.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Revillet, C.; Stevens, M.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039442 Solar wind; magnetic fields; waves; magnetohydrodynamics (MHD); Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics; Parker Data Used |
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In-flight Calibration and Data Reduction for the WISPR Instrument On Board the PSP Mission We present the calibration status and data reduction methodology for the Wide Field Imager for Solar Probe (WISPR) on board the Parker Solar Probe (PSP) mission. In particular, we describe the process for converting a raw image, measured in digital numbers (DN), to a calibrated image, measured in mean solar brightness (MSB). We also discuss details of the on board image processing including bias removal, the linearity of the electronics, pointing, geometric distortion, and photometric calibration using stellar measurements, ... Hess, Phillip; Howard, Russell; Stenborg, Guillermo; Linton, Mark; Vourlidas, Angelos; Thernisien, Arnaud; Colaninno, Robin; Rich, Nathan; Wang, Dennis; Battams, Karl; Kuroda, Natsuha; Published by: Solar Physics Published on: 06/2021 YEAR: 2021 DOI: 10.1007/s11207-021-01847-9 |
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The magnetic switchbacks observed recently by the Parker Solar Probe have raised the question about their nature and origin. One of the competing theories of their origin is the interchange reconnection in the solar corona. In this scenario, switchbacks are generated at the reconnection site between open and closed magnetic fields, and are either advected by an upflow or propagate as waves into the solar wind. In this paper we test the wave hypothesis, numerically modeling the propagation of a switchback, modeled as an embed ... Magyar, Norbert; Utz, Dominik; Erdélyi, Robertus; Nakariakov, Valery; Published by: The Astrophysical Journal Published on: 06/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abfa98 Solar wind; Magnetohydrodynamics; Alfven waves; Solar Coronal Waves; Nonlinear regression; 1534; 1964; 23; 1995; 1948; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used |
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Editorial Parker Solar Probe: Ushering a new frontier in space exploration Alves, João; Forveille, Thierry; Lellouch, Emmanuel; Shore, Steve; Zouganelis, Yannis; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202141385 |
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Context. Parker Solar Probe (PSP) is providing an unprecedented view of the Sun s corona as it progressively dips closer into the solar atmosphere with each solar encounter. Each set of observations provides a unique opportunity to test and constrain global models of the solar corona and inner heliosphere and, in turn, use the model results to provide a global context for interpreting such observations. Riley, Pete; Lionello, Roberto; Caplan, Ronald; Downs, Cooper; Linker, Jon; Badman, Samuel; Stevens, Michael; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039815 Sun: corona; Sun: heliosphere; Sun: magnetic fields; Solar wind; Sun: evolution; Interplanetary medium; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used |
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Discontinuity analysis of the leading switchback transition regions Context. Magnetic switchbacks are magnetic structures characterized as intervals of sudden reversal in the radial component of the pristine solar wind s magnetic field. Switchbacks comprise of magnetic spikes that are preceded and succeeded by switchback transition regions within which the radial magnetic field reverses. Determining switchback generation and evolution mechanisms will further our understanding of the global circulation and transportation of the Sun s open magnetic flux. Akhavan-Tafti, M.; Kasper, J.; Huang, J.; Bale, S.; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021 DOI: 10.1051/0004-6361/202039508 magnetic reconnection; magnetic fields; Solar wind; methods: data analysis; magnetohydrodynamics (MHD); instabilities; Parker Data Used |
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Unraveling the physics of the entire turbulent cascade of energy in space and astrophysical plasmas from the injection of energy at large scales to the dissipation of that energy into plasma heat at small scales, represents an overarching, open question in heliophysics and astrophysics. The fast cadence and high phase space resolution of particle velocity distribution measurements on modern spacecraft missions, such as the recently launched Parker Solar Probe, presents exciting new opportunities for identifying turbulent dis ... Verniero, J.; Howes, G.; Stewart, D.; Klein, K.; Published by: Journal of Geophysical Research (Space Physics) Published on: 05/2021 YEAR: 2021 DOI: 10.1029/2020JA028361 Solar wind; space plasma; turbulence; wave particle interaction; Parker Data Used |
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The low frequency cutoffs flo and the observed plasma frequency fp of 176 type III radio bursts are investigated in this paper. These events are observed by the Parker Solar Probe when it is in the encounter phase from the first to the fifth orbit. The result shows that the distribution of cutoffs flo is widely spread between 200 kHz and 1.6 MHz. While the plasma frequency fp at the spacecraft is between 50 and 250 kHz, which is almost all smaller than flo. The result al ... Ma, Bing; Chen, Ling; Wu, Dejin; Bale, Stuart; Published by: The Astrophysical Journal Published on: 05/2021 YEAR: 2021 DOI: 10.3847/2041-8213/abfb77 Interplanetary physics; Solar radio emission; 827; 1522; Parker Data Used |
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The first radial alignment between Parker Solar Probe and Solar Orbiter spacecraft is used to investigate the evolution of solar wind turbulence in the inner heliosphere. Assuming ballistic propagation, two 1.5 hr intervals are tentatively identified as providing measurements of the same plasma parcels traveling from 0.1 to 1 au. Using magnetic field measurements from both spacecraft, the properties of turbulence in the two intervals are assessed. Magnetic spectral density, flatness, and high-order moment scaling laws are ca ... Telloni, Daniele; Sorriso-Valvo, Luca; Woodham, Lloyd; Panasenco, Olga; Velli, Marco; Carbone, Francesco; Zank, Gary; Bruno, Roberto; Perrone, Denise; Nakanotani, Masaru; Shi, Chen; Amicis, Raffaella; De Marco, Rossana; Jagarlamudi, Vamsee; Steinvall, Konrad; Marino, Raffaele; Adhikari, Laxman; Zhao, Lingling; Liang, Haoming; Tenerani, Anna; Laker, Ronan; Horbury, Timothy; Bale, Stuart; Pulupa, Marc; Malaspina, David; MacDowall, Robert; Goetz, Keith; de Wit, Thierry; Harvey, Peter; Kasper, Justin; Korreck, Kelly; Larson, Davin; Case, Anthony; Stevens, Michael; Whittlesey, Phyllis; Livi, Roberto; Owen, Christopher; Livi, Stefano; Louarn, Philippe; Antonucci, Ester; Romoli, Marco; Brien, Helen; Evans, Vincent; Angelini, Virginia; Published by: The Astrophysical Journal Published on: 05/2021 YEAR: 2021 DOI: 10.3847/2041-8213/abf7d1 Parker Data Used; Magnetohydrodynamics; Alfven waves; Space plasmas; interplanetary turbulence; Solar wind; 1964; 23; 1544; 830; 1534 |
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Waiting-time distributions of solar flares and coronal mass ejections (CMEs) exhibit power-law-like distribution functions with slopes in the range of ατ ≍ 1.4-3.2, as observed in annual data sets during four solar cycles (1974-2012). We find a close correlation between the waiting-time power-law slope ατ and the sunspot number (SN), i.e., ατ = 1.38 + 0.01 × SN. The waiting-time distribution can be fitted with a Pareto-type function of the form N(τ) = N0 $(\tau _0+\tau )^ ... Aschwanden, Markus; de Wit, Thierry; Published by: The Astrophysical Journal Published on: 05/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abef69 Parker Data Used; Solar wind; solar flares; 1534; 1496; Astrophysics - Solar and Stellar Astrophysics |
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The Parker Solar Probe (PSP) routinely observes magnetic field deflections in the solar wind at distances less than 0.3 au from the Sun. These deflections are related to structures commonly called "switchbacks" (SBs), whose origins and characteristic properties are currently debated. Here, we use a database of visually selected SB intervals—and regions of solar wind plasma measured just before and after each SB—to examine plasma parameters, turbulent spectra from inertial to dissipation scales, and intermittency ... Martinovic, Mihailo; Klein, Kristopher; Huang, Jia; Chandran, Benjamin; Kasper, Justin; Lichko, Emily; Bowen, Trevor; Chen, Christopher; Matteini, Lorenzo; Stevens, Michael; Case, Anthony; Bale, Stuart; Published by: The Astrophysical Journal Published on: 05/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abebe5 Parker Data Used; Space plasmas; interplanetary turbulence; Solar wind; 1544; 830; 1534; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
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Between the base of the solar corona at $r=r_\textrm b$ and the Alfvén critical point at $r=r_\textrm A$, where $r$ is heliocentric distance, the solar-wind density decreases by a factor $ \mathop > \limits_∼ 10^5$, but the plasma temperature varies by a factor of only a few. In this paper, I show that such quasi-isothermal evolution out to $r=r_\textrm A$ is a generic property of outflows powered by reflection-driven Alfvén-wave (AW) turbulence, in which outward-propagating AWs partially reflect, and counter-propagating ... Published by: Journal of Plasma Physics Published on: 05/2021 YEAR: 2021 DOI: 10.1017/S0022377821000052 astrophysical plasmas; space plasma physics; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics; Parker Data Used |
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On July 11, 2020, NASA s Parker Solar Probe made its third flyby of Venus. The upper hybrid resonance emission was observed below 1,100 km (a first at Venus), revealing electron densities an order of magnitude lower than at solar maximum. These observations are consistent with a substantial variation in the density and structure of the Venusian ionosphere over the Solar Cycle. Collinson, Glyn; Ramstad, Robin; Glocer, Alex; Wilson, Lynn; Brosius, Alexandra; Published by: Geophysical Research Letters Published on: 05/2021 YEAR: 2021 DOI: 10.1029/2020GL092243 ionosphere; parker solar probe; solar cycle; upper hybrid emission; Venus; waves; Parker Data Used |
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The Dynamic Formation of Pseudostreamers Streamers and pseudostreamers structure the corona at the largest scales, as seen in both eclipse and coronagraph white-light images. Their inverted-goblet appearance encloses broad coronal loops at the Sun and tapers to a narrow radial stalk away from the star. The streamer associated with the global solar dipole magnetic field is long-lived, predominantly contains a single arcade of nested loops within it, and separates opposite-polarity interplanetary magnetic fields with the heliospheric current sheet (HCS) anchored at i ... Scott, Roger; Pontin, David; Antiochos, Spiro; DeVore, Richard; Wyper, Peter; Published by: The Astrophysical Journal Published on: 05/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abec4f Solar Physics; Solar magnetic reconnection; Solar wind; 1476; 1504; 1534; Parker Data Used |
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First Observations of Anomalous Cosmic Rays in to 36 Solar Radii NASA s Parker Solar Probe mission continues to travel closer to the Sun than any prior human-made object, with an expected closest approach of <10 solar radii (<0.046 au) by 2024. On board, the Integrated Science Investigation of the Sun instrument suite makes unprecedented in situ measurements of energetic particles in the near-Sun environment. The current low level of solar activity offers a prime opportunity to measure cosmic rays closer to the Sun than ever before. We present the first observations of anomalous cosmic ra ... Rankin, J.; McComas, D.; Leske, R.; Christian, E.; Cohen, C.; Cummings, A.; Joyce, C.; Labrador, A.; Mewaldt, R.; Posner, A.; Schwadron, N.; Strauss, R.; Stone, E.; Wiedenbeck, M.; Published by: The Astrophysical Journal Published on: 05/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abec7e cosmic rays; Solar wind; Heliosphere; Solar energetic particles; Solar Physics; solar cycle; Quiet Sun; Particle astrophysics; interplanetary magnetic fields; Plasma astrophysics; Interplanetary particle acceleration; Pickup ions; 329; 1534; 711; 1491; 1476; 1487; 1322; 96; 824; 1261; 826; 1239; Parker Data Used |
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The random advection of passive additives in a turbulent fluid plays an important role in solar physics, astrophysics, and atmospheric sciences. We concern ourselves here with the case where the fluctuations are not statistically homogeneous in space, and, hence, where the transport coefficients vary with position. Using a numerical model in which the fluid turbulence is defined kinematically, we show that the evolution of the distribution of passive tracers in the fluid is not always governed by the ordinary diffusion equat ... Published by: The Astrophysical Journal Published on: 05/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abf0b2 Plasma astrophysics; Solar magnetic fields; hydrodynamics; Astrophysical fluid dynamics; Atmospheric science; 1261; 1503; 1963; 101; 116; Parker Data Used |
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On the violation of the zeroth law of turbulence in space plasmas The zeroth law of turbulence states that, for fixed energy input into large-scale motions, the statistical steady state of a turbulent system is independent of microphysical dissipation properties. This behaviour, which is fundamental to nearly all fluid-like systems from industrial processes to galaxies, occurs because nonlinear processes generate smaller and smaller scales in the flow, until the dissipation - no matter how small - can thermalise the energy input. Using direct numerical simulations and theoretical arguments ... Meyrand, R.; Squire, J.; Schekochihin, A.; Dorland, W.; Published by: Journal of Plasma Physics Published on: 05/2021 YEAR: 2021 DOI: 10.1017/S0022377821000489 space plasma physics; astrophysical plasmas; plasma nonlinear phenomena; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Nonlinear Sciences - Chaotic Dynamics; Physics - Plasma Physics; Parker Data Used |
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PATCH: Particle Arrival Time Correlation for Heliophysics The ability to understand the fundamental nature of the physics that governs the heliosphere requires spacecraft instrumentation to measure energy transfer at kinetic scales. This translates to a time cadence resolving the proton kinetic timescales, typically of the order of the proton gyrofrequency. The downlinked survey mode data from modern spacecraft are often much lower resolution than this criterion, meaning that the higher resolution, burst mode data must be captured to study an event at kinetic time scales. Telemetry ... Verniero, J.; Howes, G.; Stewart, D.; Klein, K.; Published by: Journal of Geophysical Research (Space Physics) Published on: 05/2021 YEAR: 2021 DOI: 10.1029/2020JA028940 plasma turbulence; Solar wind; spacecraft Instrumentation; wave particle interaction; Parker Data Used |
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This research shows Part II of the Spacecraft Interaction Plasma Software (SPIS) used to model the parker solar probe (PSP) FIELDS instrument and its interactions with the Solar Wind. Flight data were used to run the PSP model and compared with models using past predicted parameters. The effect of voltage biasing between the antenna, its shield, and the spacecraft on the current balance of each surface was investigated at first perihelion (0.16AU). The model data were reduced to I-V curves to find current saturations (analys ... Diaz-Aguado, M.; Bonnell, J.; Bale, S.; Wang, J.; Gruntman, M.; Published by: Journal of Geophysical Research (Space Physics) Published on: 05/2021 YEAR: 2021 DOI: 10.1029/2020JA028689 |
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On Alfvénic Slow Wind: A Journey From the Earth Back to the Sun Comparative studies of fast and slow solar wind streams performed over the past decades have illustrated several differences between the plasma regimes for these different flows, examples including features such as temperatures, particle distribution function anisotropies, and the nature of the embedded turbulence, specifically the Alfvénicity of the fluctuations. Though this two state classification of the solar wind primarily based on flow speed has been widely adopted, more in depth studies have found that slow solar win ... Amicis, R.; Perrone, D.; Bruno, R.; Velli, M.; Published by: Journal of Geophysical Research (Space Physics) Published on: 04/2021 YEAR: 2021 DOI: 10.1029/2020JA028996 Parker Data Used; Coronal holes; interplanetary magnetic field; MHD waves and turbulence; Solar wind plasma; solar wind sources; turbulence |
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Nonlinear Ion-acoustic Waves, Ion Holes, and Electron Holes in the Near-Sun Solar Wind Nonlinear ion-acoustic waves, ion holes, and electron holes have been observed on the Parker Solar Probe at a heliocentric distance of 35 solar radii. These time domain structures contain millisecond duration electric field spikes of several mV m-1. They are observed inside or at boundaries of switchbacks in the background magnetic field. Their presence in switchbacks indicates that both electron- and ion-streaming electrostatic instabilities occur there to thermalize electron and ion beams. Mozer, F.; Bonnell, J.; Hanson, E.; Gasque, L.; Vasko, I; Published by: The Astrophysical Journal Published on: 04/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abed52 |
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How Alfvén waves energize the solar wind: heat versus work A growing body of evidence suggests that the solar wind is powered to a large extent by an Alfvén-wave (AW) energy flux. AWs energize the solar wind via two mechanisms: heating and work. We use high-resolution direct numerical simulations of reflection-driven AW turbulence (RDAWT) in a fast-solar-wind stream emanating from a coronal hole to investigate both mechanisms. In particular, we compute the fraction of the AW power at the coronal base ($P_\textrm AWb$) that is transferred to solar-wind particles via heating between ... Perez, Jean; Chandran, Benjamin; Klein, Kristopher; Martinovic, Mihailo; Published by: Journal of Plasma Physics Published on: 04/2021 YEAR: 2021 DOI: 10.1017/S0022377821000167 Parker Data Used; astrophysical plasmas; space plasma physics; plasma nonlinear phenomena; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
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Non Detection of Lightning During the Second Parker Solar Probe Venus Gravity Assist The Parker Solar Probe (PSP) spacecraft completed its second Venus gravity assist maneuver (VGA2) on December 26, 2019. For a 20 min interval surrounding closest approach, the PSP/FIELDS Radio Frequency Spectrometer (RFS) was set to "burst mode," recording radio spectra from 1.3 to 19.2 MHz at sub second cadence. We analyze this burst mode data, searching for signatures of radio frequency "sferic" emission from lightning discharges. During the burst mode interval, only four spectra were observed with strong impulsive signals ... Pulupa, Marc; Bale, Stuart; Curry, Shannon; Farrell, William; Goodrich, Katherine; Goetz, Keith; Harvey, Peter; Malaspina, David; Raouafi, Nour; Published by: Geophysical Research Letters Published on: 04/2021 YEAR: 2021 DOI: 10.1029/2020GL091751 Parker Data Used; Venus; lightning; radio; non detection; parker solar probe |
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Subproton-scale Intermittency in Near-Sun Solar Wind Turbulence Observed by the Parker Solar Probe High time-resolution solar wind magnetic field data are employed to study statistics describing intermittency near the first perihelion (∼35.6 R⊙) of the Parker Solar Probe mission. A merged data set employing two instruments on the FIELDS suite enables broadband estimation of higher-order moments of magnetic field increments, with five orders established with reliable accuracy. The duration, cadence, and low noise level of the data permit evaluation of scale dependence of the observed intermittency from the i ... Chhiber, Rohit; Matthaeus, William; Bowen, Trevor; Bale, Stuart; Published by: The Astrophysical Journal Published on: 04/2021 YEAR: 2021 DOI: 10.3847/2041-8213/abf04e Parker Data Used; Solar wind; interplanetary turbulence; Magnetohydrodynamics; Space plasmas; 1534; 830; 1964; 1544; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Physics - Geophysics; Physics - Plasma Physics |
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Observations of plasma waves by the Fields Suite and of electrons by the Solar Wind Electrons Alphas and Protons Investigation on the Parker Solar Probe provide strong evidence for pitch angle scattering of strahl-energy electrons by narrowband whistler-mode waves at radial distances less than ∼0.3 au. We present two example intervals of a few hours each that include eight waveform captures with whistler-mode waves and 26 representative electron distributions that are examined in detail. Two were narrow, seventeen were cle ... Cattell, C.; Breneman, A.; Dombeck, J.; Short, B.; Wygant, J.; Halekas, J.; Case, Tony; Kasper, J.; Larson, D.; Stevens, Mike; Whittesley, P.; Bale, S.; de Wit, Dudok; Goodrich, K.; MacDowall, R.; Moncuquet, M.; Malaspina, D.; Pulupa, M.; Published by: The Astrophysical Journal Published on: 04/2021 YEAR: 2021 DOI: 10.3847/2041-8213/abefdd Parker Data Used; Solar wind; Space plasmas; Plasma astrophysics; Interplanetary physics; Interplanetary particle acceleration; 1534; 1544; 1261; 827; 826; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics |
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Electron Acceleration during Macroscale Magnetic Reconnection The first self-consistent simulations of electron acceleration during magnetic reconnection in a macroscale system are presented. Consistent with solar flare observations, the spectra of energetic electrons take the form of power laws that extend more than two decades in energy. The drive mechanism for these nonthermal electrons is Fermi reflection in growing and merging magnetic flux ropes. A strong guide field suppresses the production of nonthermal electrons by weakening the Fermi drive mechanism. For a weak guide field t ... Arnold, H.; Drake, J.; Swisdak, M.; Guo, F.; Dahlin, J.; Chen, B.; Fleishman, G.; Glesener, L.; Kontar, E.; Phan, T.; Shen, C.; Published by: Physical Review Letters Published on: 04/2021 YEAR: 2021 DOI: 10.1103/PhysRevLett.126.135101 Parker Data Used; Physics - Plasma Physics; Astrophysics - High Energy Astrophysical Phenomena |
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Could Switchbacks Originate in the Lower Solar Atmosphere? I. Formation Mechanisms of Switchbacks The recent rediscovery of magnetic field switchbacks or deflections embedded in the solar wind flow by the Parker Solar Probe mission lead to a huge interest in the modeling of the formation mechanisms and origin of these switchbacks. Several scenarios for their generation were put forth, ranging from lower solar atmospheric origins by reconnection, to being a manifestation of turbulence in the solar wind, and so on. Here we study some potential formation mechanisms of magnetic switchbacks in the lower solar atmosphere, usin ... Magyar, Norbert; Utz, Dominik; Erdélyi, Robertus; Nakariakov, Valery; Published by: The Astrophysical Journal Published on: 04/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abec49 Parker Data Used; Solar atmosphere; Solar Physics; Magnetohydrodynamics; 1477; 1476; 1964; Astrophysics - Solar and Stellar Astrophysics |
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Pristine PSP/WISPR Observations of the Circumsolar Dust Ring near Venus s Orbit The Parker Solar Probe mission (PSP) has completed seven orbits around the Sun. The Wide-field Imager for Solar Probe (WISPR) on PSP consists of two visible light heliospheric imagers, which together image the interplanetary medium between 13°5 and 108° elongation. The PSP/WISPR nominal science observing window occurs during the solar encounters, which take place when the spacecraft (S/C) is within 0.25 au from the Sun. During Orbit 3, an extended science campaign took place while PSP transited between 0.5 and 0.25 au (dur ... Stenborg, Guillermo; Gallagher, Brendan; Howard, Russell; Hess, Phillip; Raouafi, Nour; Published by: The Astrophysical Journal Published on: 04/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abe623 Parker Data Used; Solar F corona; Interplanetary dust; Circumstellar dust; 1991; 821; 236 |
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Laboratory Study of Antenna Signals Generated by Dust Impacts on Spacecraft Space missions often carry antenna instruments that are sensitive to dust impacts, however, the understanding of signal generation mechanisms remained incomplete. A signal generation model in an analytical form is presented that provides a good agreement with laboratory measurements. The model is based on the direct and induced charging of the spacecraft from the collected and escaping fraction of free charges from the impact generated plasma cloud. A set of laboratory experiments is performed using a 20:1 scaled down model ... Shen, Mitchell; Sternovsky, Zoltan; Horányi, Mihály; Hsu, Hsiang-Wen; Malaspina, David; Published by: Journal of Geophysical Research (Space Physics) Published on: 04/2021 YEAR: 2021 DOI: 10.1029/2020JA028965 antenna instruments; cosmic dust; dust detection; Parker Data Used |
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Switchbacks Explained: Super-Parker Fields—The Other Side of the Sub-Parker Spiral We provide a simple geometric explanation for the source of switchbacks and associated large and one-sided transverse flows in the solar wind observed by the Parker Solar Probe (PSP). The more radial, sub-Parker spiral structure of the heliospheric magnetic field observed previously by Ulysses, ACE, and STEREO is created within rarefaction regions where footpoint motion from the source of fast into slow wind at the Sun creates a magnetic fieldline connection across solar wind speed shear. Conversely, when footpoints move fro ... Published by: The Astrophysical Journal Published on: 03/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abd4e6 Parker Data Used; Active Solar Corona; Solar wind; Solar Coronal Waves; Solar coronal loops; Solar coronal holes; Solar coronal plumes; Solar magnetic fields; interplanetary magnetic fields; Solar spicules; 1988; 1534; 1995; 1485; 1484; 2039; 1503; 824; 1525; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics; 85 |
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The Parker Solar Probe (PSP) aims to explore the nascent solar wind close to the Sun. Meanwhile, PSP is also expected to encounter small objects like comets and asteroids. In this work, we survey the ephemerides to find the chance of a recent encounter and then model the interaction between released dusty plasmas and solar wind plasmas. On 2019 September 2, a comet-like object, the 322P/Solar and Heliosphere Observatory, just passed its perihelion flying to a heliocentric distance of 0.12 au and swept by PSP at a relative di ... He, Jiansen; Cui, Bo; Yang, Liping; Hou, Chuanpeng; Zhang, Lei; Ip, Wing-Huen; Jia, Ying-Dong; Dong, Chuanfei; Duan, Die; Zong, Qiugang; Bale, Stuart; Pulupa, Marc; Bonnell, John; de Wit, Thierry; Goetz, Keith; Harvey, Peter; MacDowall, Robert; Malaspina, David; Published by: The Astrophysical Journal Published on: 03/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abdf4a Parker Data Used; Solar wind; Comet tails; Interplanetary dust; Asteroids; 1534; 274; 821; 72; Astrophysics - Earth and Planetary Astrophysics; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
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Source-dependent Properties of Two Slow Solar Wind States Two states of the slow solar wind are identified from in situ measurements by the Parker Solar Probe (PSP) inside 50 solar radii from the Sun. At such distances the wind measured by PSP has not yet undergone significant transformation related to the expansion and propagation of the wind. We focus in this study on the properties of the quiet solar wind with no magnetic switchbacks. The two states differ by their plasma beta, flux, and magnetic pressure. PSP s magnetic connectivity established with potential field source surfa ... Griton, Lea; Rouillard, Alexis; Poirier, Nicolas; Issautier, Karine; Moncuquet, Michel; Pinto, Rui; Published by: The Astrophysical Journal Published on: 03/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abe309 Parker Data Used; Slow solar wind; Solar wind; Solar coronal holes; Solar coronal streamers; 1873; 1534; 1484; 1486; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
