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Found 68 entries in the Bibliography.
Showing entries from 1 through 50
| 2021 |
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We report nonlinear wave-wave coupling related to whistler-mode or electron Bernstein waves in the near-Sun slow solar wind with Parker Solar Probe (PSP) data. Prominent plasma wave power enhancements usually exist near the electron gyrofrequency (f$_ce$), identified as electrostatic whistler-mode and electron Bernstein waves (Malaspina et al. 2020). We find that these plasma waves near f$_ce$ typically have a harmonic spectral structure and further classify them into three types identified by the characteristics of wave fre ... Ma, Jiuqi; Gao, Xinliang; Yang, Zhongwei; Tsurutani, Bruce; Liu, Mingzhe; Lu, Quanming; Wang, Shui; Published by: \apj Published on: sep YEAR: 2021 DOI: 10.3847/1538-4357/ac0ef4 |
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BepiColombo s cruise phase: unique opportunity for synergistic observations The investigation of multi-spacecraft coordinated observations during the cruise phase of BepiColombo (ESA/JAXA) are reported, with a particular emphasis on the recently launched missions, Solar Orbiter (ESA/NASA) and Parker Solar Probe (NASA). Despite some payload constraints, many instruments onboard BepiColombo are operating during its cruise phase simultaneously covering a wide range of heliocentric distances [0.28 AU - 0.5 AU]. Hence, the various spacecraft configurations and the combined in-situ and remote sensing meas ... Hadid, L.~Z.; enot, V.; Aizawa, S.; Milillo, A.; Zender, J.; Murakami, G.; Benkhoff, J.; Zouganelis, I.; Alberti, T.; e, Andr\; Bebesi, Z.; Califano, F.; Dimmock, A.~P.; Dosa, M.; Escoubet, C.~P.; Griton, L.; Ho, G.~C.; Horbury, T.~S.; Iwai, K.; Janvier, M.; Kilpua, E.; Lavraud, B.; Madar, A.; Miyoshi, Y.; Müller, D.; Pinto, R.~F.; Rouillard, A.~P.; Raines, J.~M.; Raouafi, N.; Sahraoui, F.; anchez-Cano, B.; Shiota, D.; Vainio, R.; Walsh, A.; Published by: Frontiers in Astronomy and Space Sciences Published on: sep YEAR: 2021 DOI: 10.3389/fspas.2021.718024 Solar wind; multi-spacecraft measurements; Inner heliosphere; Spacecraft mission; Coordinated measurements |
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BepiColombo s cruise phase: unique opportunity for synergistic observations The investigation of multi-spacecraft coordinated observations during the cruise phase of BepiColombo (ESA/JAXA) are reported, with a particular emphasis on the recently launched missions, Solar Orbiter (ESA/NASA) and Parker Solar Probe (NASA). Despite some payload constraints, many instruments onboard BepiColombo are operating during its cruise phase simultaneously covering a wide range of heliocentric distances [0.28 AU - 0.5 AU]. Hence, the various spacecraft configurations and the combined in-situ and remote sensing meas ... Hadid, L.~Z.; enot, V.; Aizawa, S.; Milillo, A.; Zender, J.; Murakami, G.; Benkhoff, J.; Zouganelis, I.; Alberti, T.; e, Andr\; Bebesi, Z.; Califano, F.; Dimmock, A.~P.; Dosa, M.; Escoubet, C.~P.; Griton, L.; Ho, G.~C.; Horbury, T.~S.; Iwai, K.; Janvier, M.; Kilpua, E.; Lavraud, B.; Madar, A.; Miyoshi, Y.; Müller, D.; Pinto, R.~F.; Rouillard, A.~P.; Raines, J.~M.; Raouafi, N.; Sahraoui, F.; anchez-Cano, B.; Shiota, D.; Vainio, R.; Walsh, A.; Published by: Frontiers in Astronomy and Space Sciences Published on: sep YEAR: 2021 DOI: 10.3389/fspas.2021.718024 Solar wind; multi-spacecraft measurements; Inner heliosphere; Spacecraft mission; Coordinated measurements |
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The first computations of the compressible energy transfer rate from \raisebox-0.5ex\textasciitilde0.2 up to \raisebox-0.5ex\textasciitilde1.7 au is obtained using Parker Solar Probe (PSP), Time History of Events and Macroscale Interactions during Substorms (THEMIS), and Mars Atmosphere and Volatile EvolutioN (MAVEN) observations. Using a recently derived exact relation for isothermal magnetohydrodynamics turbulence, the compressible energy cascade rate, \ensuremath\varepsilon$_C$, is computed for hundred of events at differ ... es, Andr\; Sahraoui, F.; Hadid, L.~Z.; Huang, S.~Y.; Romanelli, N.; Galtier, S.; DiBraccio, G.; Halekas, J.; Published by: \apj Published on: sep YEAR: 2021 DOI: 10.3847/1538-4357/ac0af5 Solar wind; Fast solar wind; Slow solar wind; Interplanetary physics; 1534; 1872; 1873; 827; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Parker Data Used |
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Context. Alfv\ enic fluctuations are ubiquitous features observed in solar wind, especially in the inner heliosphere. However, strong Alfv\ enic fluctuations are recovered in the near-Earth solar wind too, mainly in fast streams, but also in some cases in slow wind intervals, as highlighted in recent studies. \ Aims: The present study focuses on a statistical comparison between different phases of solar cycles 23 and 24 with regard to the Alfv\ enic content of solar wind fluctuations. Particular attention is devoted to the A ... Amicis, R.; Alielden, K.; Perrone, D.; Bruno, R.; Telloni, D.; Raines, J.~M.; Lepri, S.~T.; Zhao, L.; Published by: \aap Published on: oct YEAR: 2021 DOI: 10.1051/0004-6361/202140600 Parker Data Used; plasmas; Sun: heliosphere; Solar wind; turbulence; methods: data analysis; Interplanetary medium |
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Small-scale Magnetic Flux Ropes with Field-aligned Flows via the PSP In Situ Observations Magnetic flux rope, formed by the helical magnetic field lines, can sometimes maintain its shape while carrying significant plasma flow that is aligned with the local magnetic field. We report the existence of such structures and static flux ropes by applying the Grad-Shafranov-based algorithm to the Parker Solar Probe in situ measurements in the first five encounters. These structures are detected at heliocentric distances, ranging from 0.13 to 0.66 au, in a 4-month time period. We find that flux ropes with field-aligned fl ... Chen, Yu; Hu, Qiang; Zhao, Lingling; Kasper, Justin; Huang, Jia; Published by: \apj Published on: jun YEAR: 2021 DOI: 10.3847/1538-4357/abfd30 Parker Data Used; Solar wind; Astronomy data analysis; interplanetary turbulence; Solar magnetic reconnection; Solar magnetic fields; 1534; 1858; 830; 1504; 1503; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
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An Interplanetary Type IIIb Radio Burst Observed by Parker Solar Probe and Its Emission Mechanism Type IIIb radio bursts were identified as a chain of quasi-periodic striae in dynamic spectra, drifting from high to low frequencies in a manner similar to type III bursts, which fine structures may provide a clue to a better understanding of emission mechanisms. The approaching observation of the Parker Solar Probe (PSP) spacecraft provides a new chance of probing type IIIb bursts in the vicinity of the Sun. In this Letter, combining the in situ measurement of PSP and the empirical model of solar atmospheres in open magneti ... Chen, Ling; Ma, Bing; Wu, Dejin; Zhao, Guoqing; Tang, Jianfei; Bale, Stuart; Published by: \apjl Published on: jul YEAR: 2021 DOI: 10.3847/2041-8213/ac0b43 Parker Data Used; Solar radio emission; Interplanetary physics; 1522; 827 |
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Various forms of exact laws governing magnetohydrodynamic (MHD) turbulence have been derived either in the incompressibility limit, or for isothermal compressible flows. Here we propose a more general method that allows us to obtain such laws for any turbulent isentropic flow (i.e., constant entropy). We demonstrate that the known MHD exact laws (incompressible and isothermal) and the new (polytropic) one can be obtained as specific cases of the general law when the corresponding closure equation is stated. We also recover a ... Published by: \apj Published on: jul YEAR: 2021 DOI: 10.3847/1538-4357/ac0337 Solar wind; Solar Physics; Parker Data Used; Magnetohydrodynamics; Plasma astrophysics; Plasma physics; interplanetary turbulence; 1534; 1476; 1964; 1261; 2089; 830; Physics - Plasma Physics; Physics - Fluid Dynamics |
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Turbulence transport in the solar corona: Theory, modeling, and Parker Solar Probe A primary goal of the Parker Solar Probe (PSP) Mission is to answer the outstanding question of how the solar corona plasma is heated to the high temperatures needed for the acceleration of the solar wind. Various heating mechanisms have been suggested, but one that is gaining increasing credence is associated with the dissipation of low frequency magnetohyrodynamic (MHD) turbulence. However, the MHD turbulence models come in several flavors: one in which outwardly propagating Alfv\ en waves experience reflection from the la ... Zank, G.~P.; Zhao, L.; Adhikari, L.; Telloni, D.; Kasper, J.~C.; Bale, S.~D.; Published by: Physics of Plasmas Published on: aug YEAR: 2021 DOI: 10.1063/5.0055692 |
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We present a statistical analysis for the characteristics and spatial evolution of the interplanetary discontinuities (IDs) in the solar wind, from 0.13-0.9 au, by using the Parker Solar Probe measurements on Orbits 4 and 5. We collected 3948 IDs, including 2511 rotational discontinuities (RDs) and 557 tangential discontinuities (TDs), with the remnant unidentified. The statistical results show that (1) the ID occurrence rate decreases from 200 events per day at 0.13 au to 1 event per day at 0.9 au, following a spatial scali ... Liu, Y.~Y.; Fu, H.~S.; Cao, J.~B.; Liu, C.~M.; Wang, Z.; Guo, Z.~Z.; Xu, Y.; Bale, S.~D.; Kasper, J.~C.; Published by: \apj Published on: aug YEAR: 2021 DOI: 10.3847/1538-4357/ac06a1 Interplanetary discontinuities; Solar wind; interplanetary magnetic fields; Magnetohydrodynamics; 820; 1534; 824; 1964; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics; Parker Data Used |
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Assessing the Role of Interchange Reconnection in Forming Switchbacks Abrupt deflections of the magnetic field in the solar wind, so called switchbacks, are frequently observed by the Parker Solar Probe (PSP) during its first two orbits and are believed to play an important role in unveiling the nature of solar corona heating and solar wind acceleration in the inner heliosphere. Many attempts were made recently to understand the nature of switchbacks. However, the origin, propagation, and evolution of switchbacks are still under debate. In this study, we attempt to use the linear theory of ... Liang, H.; Zank, G.~P.; Nakanotani, M.; Zhao, L.; Published by: \apj Published on: aug YEAR: 2021 DOI: 10.3847/1538-4357/ac0a73 Space plasmas; Solar wind; Solar magnetic fields; Parker Data Used; Solar magnetic reconnection; 1544; 1534; 1503; 1504 |
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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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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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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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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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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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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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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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The scaling of the turbulent spectra provides a key measurement that allows us to discriminate between different theoretical predictions of turbulence. In the solar wind, this has driven a large number of studies dedicated to this issue using in situ data from various orbiting spacecraft. While a semblance of consensus exists regarding the scaling in the magnetohydrodynamic (MHD) and dispersive ranges, the precise scaling in the transition range and the actual physical mechanisms that control it remain open questions. Using ... Huang, S; Sahraoui, F.; Andrés, N.; Hadid, L.; Yuan, Z.; He, J.; Zhao, J.; Galtier, S.; Zhang, J.; Deng, X.; Jiang, K.; Yu, L.; Xu, S.; Xiong, Q; Wei, Y; de Wit, Dudok; Bale, S.; Kasper, J.; Published by: The Astrophysical Journal Published on: 03/2021 YEAR: 2021 DOI: 10.3847/2041-8213/abdaaf Parker Data Used; Solar wind; interplanetary turbulence; Solar coronal heating; 1534; 830; 1989; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics |
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The scaling of the turbulent spectra provides a key measurement that allows us to discriminate between different theoretical predictions of turbulence. In the solar wind, this has driven a large number of studies dedicated to this issue using in situ data from various orbiting spacecraft. While a semblance of consensus exists regarding the scaling in the magnetohydrodynamic (MHD) and dispersive ranges, the precise scaling in the transition range and the actual physical mechanisms that control it remain open questions. Using ... Huang, S; Sahraoui, F.; Andrés, N.; Hadid, L.; Yuan, Z.; He, J.; Zhao, J.; Galtier, S.; Zhang, J.; Deng, X.; Jiang, K.; Yu, L.; Xu, S.; Xiong, Q; Wei, Y; de Wit, Dudok; Bale, S.; Kasper, J.; Published by: The Astrophysical Journal Published on: 03/2021 YEAR: 2021 DOI: 10.3847/2041-8213/abdaaf Parker Data Used; Solar wind; interplanetary turbulence; Solar coronal heating; 1534; 830; 1989; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics |
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Shi, Chen; Zhao, Jinsong; Huang, Jia; Wang, Tieyan; Wu, Dejin; Chen, Yu; Hu, Qiang; Kasper, Justin; Bale, Stuart; Published by: \apjl Published on: 02/2021 YEAR: 2021 DOI: 10.3847/2041-8213/abdd28 |
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The addition of Parker Solar Probe (PSP) to the Heliophysics System Observatory has allowed for the unprecedented ability to study Corotating Interaction Regions (CIRs) at multiple radial distances without significant temporal/longitudinal variations. On September 19, 2019, PSP observed a CIR at ∼0.5 au when it was nearly radially aligned with the Solar Terrestrial Relations Observatory Ahead (STEREO A) spacecraft at ∼1 au, allowing for an unambiguous assessment of the radial evolution of a single CIR. Bulk plasma and ma ... Allen, R.; Ho, G.; Mason, G.; Li, G.; Jian, L.; Vines, S.; Schwadron, N.; Joyce, C.; Bale, S.; Bonnell, J.; Case, A.; Christian, E.; Cohen, C.; Desai, M.; Filwett, R.; Goetz, K.; Harvey, P.; Hill, M.; Kasper, J.; Korreck, K.; Lario, D.; Larson, D.; Livi, R.; MacDowall, R.; Malaspina, D.; McComas, D.; McNutt, R.; Mitchell, D.; Paulson, K.; Pulupa, M.; Raouafi, N.; Stevens, M.; Whittlesey, P.; Wiedenbeck, M.; Published by: Geophysical Research Letters Published on: 02/2021 YEAR: 2021 DOI: 10.1029/2020GL091376 Parker Data Used; CIRs; parker solar probe; Solar wind; STEREO; suprathermal ions |
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Kinetic-Scale Turbulence in the Venusian Magnetosheath Bowen, T.~A.; Bale, S.~D.; Bandyopadhyay, R.; Bonnell, J.~W.; Case, A.; Chasapis, A.; Chen, C.~H.~K.; Curry, S.; de Wit, Dudok; Goetz, K.; Goodrich, K.; Gruesbeck, J.; Halekas, J.; Harvey, P.~R.; Howes, G.~G.; Kasper, J.~C.; Korreck, K.; Larson, D.; Livi, R.; MacDowall, R.~J.; Malaspina, D.~M.; Mallet, A.; McManus, M.~D.; Page, B.; Pulupa, M.; Raouafi, N.; Stevens, M.~L.; Whittlesey, P.; Published by: \grl Published on: 01/2021 YEAR: 2021 DOI: 10.1029/2020GL090783 |
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Plumelets: Dynamic Filamentary Structures in Solar Coronal Plumes Uritsky, V.~M.; DeForest, C.~E.; Karpen, J.~T.; DeVore, C.~R.; Kumar, P.; Raouafi, N.~E.; Wyper, P.~F.; Published by: \apj Published on: 01/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abd186 Solar coronal holes; Solar activity; Solar coronal transients; Solar Coronal Waves; Solar magnetic reconnection; Solar wind; Plasma jets; Solar coronal plumes; Solar extreme ultraviolet emission; Direct imaging; Astronomy data analysis; Solar oscillations; 1484; 1475; 312; 1995; 1504; 1534; 1263; 2039; 1493; 387; 1858; 1515; Astrophysics - Solar and Stellar Astrophysics |
| 2020 |
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Modeling proton and electron heating in the fast solar wind Context. The Parker Solar Probe (PSP) measures solar wind protons and electrons near the Sun. To study the thermodynamic properties of electrons and protons, we include electron effects, such as distributed turbulent heating between protons and electrons, Coulomb collisions between protons and electrons, and heat conduction of electrons. \ Aims: We develop a general theoretical model of nearly incompressible magnetohydrodynamic (NI MHD) turbulence coupled with a solar wind model that includes electron pressure and heat flux. ... Adhikari, L.; Zank, G.P.; Zhao, L.-L.; Nakanotani, M.; Tasnim, S.; Published by: Astronomy and Astrophysics Published on: jun YEAR: 2020 DOI: "10.1051/0004-6361/202039297" |
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Enhanced proton parallel temperature inside patches of switchbacks in the inner heliosphere Context. Switchbacks are discrete angular deflections in the solar wind magnetic field that have been observed throughout the heliosphere. Recent observations by Parker Solar Probe (PSP) have revealed the presence of patches of switchbacks on the scale of hours to days, separated by quieter radial fields. \ Aims: We aim to further diagnose the origin of these patches using measurements of proton temperature anisotropy that can illuminate possible links to formation processes in the solar corona. \ Methods: We fitted 3D bi- ... Woodham, L.; Horbury, T.; Matteini, L.; Woolley, T.; Laker, R.; Bale, S.; Nicolaou, G.; Stawarz, J.; Stansby, D.; Hietala, H.; Larson, D.; Livi, R.; Verniero, J.; McManus, M.; Kasper, J.; Korreck, K.; Raouafi, N.; Moncuquet, M.; Pulupa, M.; Published by: Astronomy and Astrophysics Published on: jun YEAR: 2020 DOI: "10.1051/0004-6361/202039415" |
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Enhanced proton parallel temperature inside patches of switchbacks in the inner heliosphere Context. Switchbacks are discrete angular deflections in the solar wind magnetic field that have been observed throughout the heliosphere. Recent observations by Parker Solar Probe (PSP) have revealed the presence of patches of switchbacks on the scale of hours to days, separated by quieter radial fields. \ Aims: We aim to further diagnose the origin of these patches using measurements of proton temperature anisotropy that can illuminate possible links to formation processes in the solar corona. \ Methods: We fitted 3D bi- ... Woodham, L.; Horbury, T.; Matteini, L.; Woolley, T.; Laker, R.; Bale, S.; Nicolaou, G.; Stawarz, J.; Stansby, D.; Hietala, H.; Larson, D.; Livi, R.; Verniero, J.; McManus, M.; Kasper, J.; Korreck, K.; Raouafi, N.; Moncuquet, M.; Pulupa, M.; Published by: Astronomy and Astrophysics Published on: jun YEAR: 2020 DOI: "10.1051/0004-6361/202039415" |
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A living catalog of stream interaction regions in the Parker Solar Probe era Stream interaction regions (SIRs) and corotating interaction regions (CIRs) are important phenomena in heliospheric physics. These large-scale structures vary temporally and spatially, both in latitude and with radial distance. The additions of Parker Solar Probe (PSP) and Solar Orbiter have allowed for investigations into the radial evolution of these structures over a wide range of heliocentric distances for the first time since the Helios era. To better enable investigations of SIRs and CIRs within the inner heliosphere, ... Allen, R.; Ho, G.; Jian, L.; Vines, S.; Bale, S.; Case, A.; Hill, M.; Joyce, C.; Kasper, J.; Korreck, K.; Malaspina, D.; McComas, D.; McNutt, R.; Möstl, C.; Odstrcil, D.; Raouafi, N.; Schwadron, N.; Stevens, M.; Published by: Astronomy and Astrophysics Published on: jun YEAR: 2020 DOI: "10.1051/0004-6361/202039833" |
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Turbulence Characteristics of Switchback and Nonswitchback Intervals Observed by Parker Solar Probe We use Parker Solar Probe (PSP) in situ measurements to analyze the characteristics of solar wind turbulence during the first solar encounter covering radial distances between 35.7R and 41.7R. In our analysis we isolate so-called switchback (SB) intervals (folded magnetic field lines) from nonswitchback (NSB) intervals, which mainly follow the Parker spiral field. Using a technique based on conditioned correlation functions, we estimate the power spectra of Elsasser, magnetic, and bulk velocity fields separately in the SB an ... Bourouaine, Sofiane; Perez, Jean; Klein, Kristopher; Chen, Christopher; Martinovic, Mihailo; Bale, Stuart; Kasper, Justin; Raouafi, Nour; Published by: ASTROPHYSICAL JOURNAL LETTERS Published on: 12/2020 YEAR: 2020 DOI: 10.3847/2041-8213/abbd4a |
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Magnetohydrodynamic Turbulent Evolution of a Magnetic Cloud in the Outer Heliosphere Telloni, Daniele; Zhao, Lingling; Zank, Gary; Liang, Haoming; Nakanotani, Masaru; Adhikari, Laxman; Carbone, Francesco; Amicis, Raffaella; Perrone, Denise; Bruno, Roberto; Dasso, Sergio; Published by: \apjl Published on: 12/2020 YEAR: 2020 DOI: 10.3847/2041-8213/abcb03 Parker Data Used; Magnetohydrodynamics; interplanetary turbulence; Solar coronal mass ejections; interplanetary magnetic fields; Heliosphere; Solar wind; Solar magnetic reconnection; 1964; 830; 310; 824; 711; 1534; 1504 |
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We propose a turbulence-driven\ solar\ wind model for a fast\ solar\ wind flow in an open coronal hole where the\ solar\ wind flow and the magnetic field are highly aligned. We compare the numerical results of our model with\ Parker\ Solar\ Probe\ measurements of the fast\ solar\ wind flow and find good agreement between them. We find that (1) the majority quasi-2D turbulence is mainly responsible for coronal heating, raising the temperature to about similar to 1 ... Adhikari, L.; Zank, G.; Zhao, L.-L.; Published by: The Astrophysical Journal Published on: 10/2020 YEAR: 2020 DOI: 10.3847/1538-4357/abb132 |
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The Origin of Switchbacks in the Solar Corona: Linear Theory The origin, structure, and propagation characteristics of a switchback are compelling questions posed by Parker Solar Probe (PSP) observations of velocity spikes and magnetic field reversals. By assuming interchange reconnection between coronal loop and open magnetic field, we show that this results in the generation of upward (into the heliosphere) and downward complex structures propagating at the fast magnetosonic speed (i.e., the Alfvén speed in the low plasma beta corona) that can have an arbitrary radial magnetic fiel ... Zank, G.; Nakanotani, M.; Zhao, L.-L.; Adhikari, L.; Kasper, J.; Published by: The Astrophysical Journal Published on: 10/2020 YEAR: 2020 DOI: 10.3847/1538-4357/abb828 Parker Data Used; Active Solar Corona; Solar Coronal Waves; interplanetary turbulence |
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Cross Helicity of the 2018 November Magnetic Cloud Observed by the Parker Solar Probe Magnetic clouds are large-scale transient structures in the solar wind with low plasma-beta, low-amplitude magnetic field fluctuations, and twisted field lines with both ends often connected to the Sun. Their inertial-range turbulent properties have not been examined in detail. In this Letter, we analyze the normalized cross helicity, sigma(c), and residual energy, sigma(r), of plasma fluctuations in the 2018 November magnetic cloud observed at 0.25.au by the Parker Solar Probe. A low value of |sigma(c)| was present in th ... Good, S.; Kilpua, E.; Ala-Lahti, M.; Osmane, A.; Bale, S.; Zhao, L.-L.; Published by: The Astrophysical Journal Published on: 09/2020 YEAR: 2020 DOI: 10.3847/2041-8213/abb021 interplanetary magnetic fields; interplanetary turbulence; Parker Data Used; parker solar probe; Solar coronal mass ejections; Solar Probe Plus; Solar wind |
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Zank, G.~P.; Nakanotani, M.; Zhao, L.; Adhikari, L.; Telloni, D.; Published by: \apj Published on: 09/2020 YEAR: 2020 DOI: 10.3847/1538-4357/abad30 |
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Microinstabilities and waves excited at moderate-Mach-number perpendicular shocks in the near-Sun solar wind are investigated by full particle-in-cell simulations. By analyzing the dispersion relation of fluctuating field components directly issued from the shock simulation, we obtain key findings concerning wave excitations at the shock front: (1) at the leading edge of the foot, two types of electrostatic (ES) waves are observed. The relative drift of the reflected ions versus the electrons triggers an electron cyclotro ... Yang, Zhongwei; Liu, Ying; Matsukiyo, Shuichi; Lu, Quanming; Guo, Fan; Liu, Mingzhe; Xie, Huasheng; Gao, Xinliang; Guo, Jun; Published by: The Astrophysical Journal Published on: 09/2020 YEAR: 2020 DOI: 10.3847/2041-8213/abaf59 Interplanetary shocks; parker solar probe; Plasma astrophysics; Plasma physics; Solar Probe Plus; Space plasmas |
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Polytropic Behavior of Solar Wind Protons Observed by Parker Solar Probe A polytropic process describes the transition of a fluid from one state to another through a specific relationship between the fluid density and temperature. The value of the polytropic index that governs this relationship determines the heat transfer and the effective degrees of freedom during a specific process. In this study, we analyze\ solar\ wind proton plasma measurements, obtained by the Faraday cup instrument on board the\ Parker\ Solar\ Probe. We examine the large-scale variations of the ... Nicolaou, Georgios; Livadiotis, George; Wicks, Robert; Verscharen, Daniel; Maruca, Bennett; Published by: The Astrophysical Journal Published on: 09/2020 YEAR: 2020 DOI: 10.3847/1538-4357/abaaae Parker Data Used; parker solar probe; Solar Physics; Solar Probe Plus; Solar wind; Space plasmas |
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Context. The launch of\ Parker\ Solar\ Probe\ (PSP) in 2018, followed by\ Solar\ Orbiter (SO) in February 2020, has opened a new window in the exploration of\ solar\ magnetic activity and the origin of the heliosphere. These missions, together with other space observatories dedicated to\ solar\ observations, such as the\ Solar\ Dynamics Observatory, Hinode, IRIS, STEREO, and SOHO, with complementary in situ observations from WIND and ACE, and ground based multi-w ... Velli, M.; Harra, L.; Vourlidas, A.; Schwadron, N.; Panasenco, O.; Liewer, P.; Müller, D.; Zouganelis, I.; St Cyr, O.; Gilbert, H.; Nieves-Chinchilla, T.; Auchère, F.; Berghmans, D.; Fludra, A.; Horbury, T.; Howard, R.; Krucker, S.; Maksimovic, M.; Owen, C.; iguez-Pacheco, Rodr\; Romoli, M.; Solanki, S.; Wimmer-Schweingruber, R.; Bale, S.; Kasper, J.; McComas, D.; Raouafi, N.; Martinez-Pillet, V.; Walsh, A.; De Groof, A.; Williams, D.; Published by: Astronomy \& Astrophysics Published on: 09/2020 YEAR: 2020 DOI: 10.1051/0004-6361/202038245 Parker Data Used; parker solar probe; Solar Probe Plus; Solar wind; solar-terrestrial relations; Sun: atmosphere; Sun: corona; Sun: heliosphere; Sun: magnetic fields |
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Spectral Features in Field-aligned Solar Wind Turbulence from Parker Solar Probe Observations Parker Solar Probe (PSP) observed a large variety of Alfv\ enic fluctuations in the fast and slow solar wind flow during its two perihelia. The properties of Alfv\ enic solar wind turbulence have been studied for decades in the near-Earth environment. A spectral index of -5/3 or -2 for magnetic field fluctuations has been observed using spacecraft measurements, which can be explained by turbulence theories of nearly incompressible magnetohydrodynamics (NI MHD) or critical balance. In this study, a rigorous search of field ... Zhao, L.-L.; Zank, G.; Adhikari, L.; Nakanotani, M.; Telloni, D.; Carbone, F.; Published by: The Astrophysical Journal Published on: 08/2020 YEAR: 2020 DOI: 10.3847/1538-4357/ab9b7e interplanetary turbulence; Parker Data Used; parker solar probe; Solar Probe Plus; Solar wind; Spectral index |
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The nature of the plasma wave modes around the ion kinetic scales in highly Alfv\ enic slow solar wind turbulence is investigated using data from the NASA\textquoterights Parker Solar Probe taken in the inner heliosphere, at 0.18 au from the Sun. The joint distribution of the normalized reduced magnetic helicity σm (θRB, τ) is obtained, where θRB is the angle between the local mean magnetic field and the radial direction and τ is the temporal scale. Two populations around ion scales a ... Huang, S; Zhang, J.; Sahraoui, F.; He, J.; Yuan, Z.; es, Andr\; Hadid, L.; Deng, X.; Jiang, K.; Yu, L.; Xiong, Q; Wei, Y; Xu, S.; Bale, S.; Kasper, J.; Published by: The Astrophysical Journal Published on: 07/2020 YEAR: 2020 DOI: 10.3847/2041-8213/ab9abb 1261; 1534; 1544; 1693; 1873; 23; 711; 824; 830; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
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We present model calculations of the transport processes of solar energetic particles in the corona and interplanetary medium for two events detected by Parker Solar Probe near its second perihelion on 2019 April 2 and April 4. In the 2019 April 2 event, the \<100 keV proton differential intensity measured by the Integrated Science Investigation of the Sun Low-Energy Energetic Particle instrument increased by more than a factor of 10 above the pre-event intensity, whereas the \~1 MeV proton differential intensity detec ... Zhao, Lulu; Zhang, Ming; Lario, David; Published by: The Astrophysical Journal Published on: 07/2020 YEAR: 2020 DOI: 10.3847/1538-4357/ab97b3 Parker Data Used; parker solar probe; Solar energetic particles; Solar Probe Plus |
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Raghav, Anil; Gaikwad, Sandesh; Wang, Yuming; Shaikh, Zubair; Mishra, Wageesh; Zao, Ake; Published by: \mnras Published on: 06/2020 YEAR: 2020 DOI: 10.1093/mnras/staa1189 Sun: coronal mass ejections; solar-terrestrial relations; Solar wind |
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We present heliospheric current sheet (HCS) and plasma sheet (HPS) observations during Parker Solar Probe\textquoterights (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 Su ... Lavraud, B.; Fargette, N.; eville, V.; Szabo, A.; Huang, J.; Rouillard, A.; Viall, N.; Phan, T.; Kasper, J.; Bale, S.; Berthomier, M.; Bonnell, J.; Case, A.; de Wit, Dudok; Eastwood, J.; enot, V.; Goetz, K.; Griton, L.; Halekas, J.; Harvey, P.; Kieokaew, R.; Klein, K.; Korreck, K.; Kouloumvakos, A.; Larson, D.; Lavarra, M.; Livi, R.; Louarn, P.; MacDowall, R.; Maksimovic, M.; Malaspina, D.; Nieves-Chinchilla, T.; Pinto, R.; Poirier, N.; Pulupa, M.; Raouafi, N.; Stevens, M.; Toledo-Redondo, S.; Whittlesey, P.; Published by: The Astrophysical Journal Published on: 05/2020 YEAR: 2020 DOI: 10.3847/2041-8213/ab8d2d |
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One of the discoveries of the Parker Solar Probe during its first encounters with the Sun is ubiquitous presence of relatively small-scale structures standing out as sudden deflections of the magnetic field. They were named "switchbacks" since some of them show a full reversal of the radial component of the magnetic field and then return to "regular" conditions. We carried out an analysis of three typical switchback structures having different characteristics: I. Alfv\ enic structure, where the variations of the magnetic ... Krasnoselskikh, V.; Larosa, A.; Agapitov, O.; de Wit, Dudok; Moncuquet, M.; Mozer, F.; Stevens, M.; Bale, S.; Bonnell, J.; Froment, C.; Goetz, K.; Goodrich, K.; Harvey, P.; Kasper, J.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Raouafi, N.; Revillet, C.; Velli, M.; Wygant, J.; Published by: The Astrophysical Journal Published on: 04/2020 YEAR: 2020 DOI: 10.3847/1538-4357/ab7f2d Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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In this paper, we present an analysis of the internal structure of a coronal mass ejection (CME) detected by in situ instruments on board the Parker Solar Probe (PSP) spacecraft during its first solar encounter. On 2018 November 11 at 23:53 UT, the FIELDS magnetometer measured an increase in strength of the magnetic field as well as a coherent change in the field direction. The SWEAP instrument simultaneously detected a low proton temperature and signatures of bidirectionality in the electron pitch angle distribution (PAD ... Nieves-Chinchilla, Teresa; Szabo, Adam; Korreck, Kelly; Alzate, Nathalia; Balmaceda, Laura; Lavraud, Benoit; Paulson, Kristoff; Narock, Ayris; Wallace, Samantha; Jian, Lan; Luhmann, Janet; Morgan, Huw; Higginson, Aleida; Arge, Charles; Bale, Stuart; Case, Anthony; de Wit, Thierry; Giacalone, Joe; Goetz, Keith; Harvey, Peter; Jones-Melosky, Shaela; Kasper, J.; Larson, Davin; Livi, Roberto; McComas, David; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Raouafi, Nour; Schwadron, Nathan; Stevens, Michael; Whittlesey, Phyllis; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab61f5 |
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During the Parker Solar Probe\textquoterights (PSP) first perihelion pass, the spacecraft reached within a heliocentric distance of ̃37 R☉ and observed numerous magnetic and flow structures characterized by sharp gradients. To better understand these intermittent structures in the young solar wind, an important property to examine is their degree of correlation in time and space. To this end, we use the well-tested partial variance of increments (PVI) technique to identify intermittent events in FIELDS and S ... Chhiber, Rohit; Goldstein, M; Maruca, B.; Chasapis, A.; Matthaeus, W.; Ruffolo, D.; Bandyopadhyay, R.; Parashar, T.; Qudsi, R.; de Wit, Dudok; Bale, S.; Bonnell, J.; Goetz, K.; Harvey, P.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Kasper, J.; Korreck, K.; Case, A.; Stevens, M.; Whittlesey, P.; Larson, D.; Livi, R.; Velli, M.; Raouafi, N.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab53d2 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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Detailed Imaging of Coronal Rays with the Parker Solar Probe The Wide-field Imager for Solar PRobe (WISPR) obtained the first high-resolution images of coronal rays at heights below 15 R☉ when the Parker Solar Probe (PSP) was located inside 0.25 au during the first encounter. We exploit these remarkable images to reveal the structure of coronal rays at scales that are not easily discernible in images taken from near 1 au. To analyze and interpret WISPR observations, which evolve rapidly both radially and longitudinally, we construct a latitude versus time map using the ... Poirier, Nicolas; Kouloumvakos, Athanasios; Rouillard, Alexis; Pinto, Rui; Vourlidas, Angelos; Stenborg, Guillermo; Valette, Emeline; Howard, Russell; Hess, Phillip; Thernisien, Arnaud; Rich, Nathan; Griton, Lea; Indurain, Mikel; Raouafi, Nour-Edine; Lavarra, Michael; eville, Victor; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab6324 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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Enhanced Energy Transfer Rate in Solar Wind Turbulence Observed near the Sun from Parker Solar Probe 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, mu ... Bandyopadhyay, Riddhi; Goldstein, M.; Maruca, B.; Matthaeus, W.; Parashar, T.; Ruffolo, D.; Chhiber, R.; Usmanov, A.; Chasapis, A.; Qudsi, R.; Bale, Stuart; Bonnell, J.; de Wit, Thierry; Goetz, Keith; Harvey, Peter; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Kasper, J.; Korreck, K.; Case, A.; Stevens, M.; Whittlesey, P.; Larson, D.; Livi, R.; Klein, K.; Velli, M.; Raouafi, N.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab5dae Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
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The Parker Solar Probe (PSP) observed an interplanetary coronal mass ejection (ICME) event during its first orbit around the Sun, among many other events. This event is analyzed by applying a wavelet analysis technique to obtain the reduced magnetic helicity, cross helicity, and residual energy, the first two of which are magnetohydrodynamics (MHD) invariants. Our results show that the ICME, as a large-scale magnetic flux rope, possesses high magnetic helicity, very low cross helicity, and highly negative residual energy, ... Zhao, L.-L.; Zank, G.; Adhikari, L.; Hu, Q.; Kasper, 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.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab4ff1 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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Parker Solar Probe In Situ Observations of Magnetic Reconnection Exhausts during Encounter 1 Magnetic reconnection in current sheets converts magnetic energy into particle energy. The process may play an important role in the acceleration and heating of the solar wind close to the Sun. Observations from Parker Solar Probe (PSP) provide a new opportunity to study this problem, as it measures the solar wind at unprecedented close distances to the Sun. During the first orbit, PSP encountered a large number of current sheets in the solar wind through perihelion at 35.7 solar radii. We performed a comprehensive survey ... Phan, T.; Bale, S.; Eastwood, J.; Lavraud, B.; Drake, J.; Oieroset, M.; Shay, M.; Pulupa, M.; Stevens, M.; MacDowall, R.; Case, A.; Larson, D.; Kasper, J.; Whittlesey, P.; Szabo, A.; Korreck, K.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Harvey, P.; Horbury, T.; Livi, R.; Malaspina, D.; Paulson, K.; Raouafi, N.; Velli, M.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab55ee Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
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Measures of Scale-dependent Alfv\ enicity in the First PSP Solar Encounter The solar wind shows periods of highly Alfv\ enic activity, where velocity fluctuations and magnetic fluctuations are aligned or antialigned with each other. It is generally agreed that solar wind plasma velocity and magnetic field fluctuations observed by the Parker Solar Probe (PSP) during the first encounter are mostly highly Alfv\ enic. However, quantitative measures of Alfv\ enicity are needed to understand how the characterization of these fluctuations compares with standard measures from prior missions in the inner ... Parashar, T.; Goldstein, M.; Maruca, B.; Matthaeus, W.; Ruffolo, D.; Bandyopadhyay, R.; Chhiber, R.; Chasapis, A.; Qudsi, R.; Vech, D.; Roberts, D.; Bale, S.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Harvey, P.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Kasper, J.; Korreck, K.; Case, A.; Stevens, M.; Whittlesey, P.; Larson, D.; Livi, R.; Velli, M.; Raouafi, N.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab64e6 |
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