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Found 60 entries in the Bibliography.
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2022 |
Prior observations of the near-Sun solar wind (sunward of 0.25 au) identified frequent, intense plasma waves near the local electron cyclotron frequency (f $_ce$), and its harmonics. In this Letter, it is shown that near-f $_ce$ wave properties are consistent with generation via interaction between the observing spacecraft s ion wake and the ambient plasma and magnetic fields. This result implies that many observed near-f $_ce$ waves are not intrinsic to the unobstructed solar wind flow, and therefore are unlikely to play a ... Malaspina, David; Tigik, Sabrina; Vaivads, Andris; Published by: \apjl Published on: sep YEAR: 2022   DOI: 10.3847/2041-8213/ac8c8f Parker Data Used; Solar wind; space vehicles; Space plasmas; 1534; 1549; 1544 |
Switchbacks are localized deviations from the nominal Parker spiral field in the solar wind. In this study, we investigate the electron distributions inside switchbacks, focusing primarily on the suprathermal (halo and strahl) populations. We explore electron parameters in relation to the angle of rotation of the magnetic field from radial to determine whether electron distributions observed within switchbacks have any differences from those outside of switchbacks. Our observations reveal several trends in the suprathermal e ... Nair, Raaman; Halekas, Jasper; Whittlesey, Phyllis; Larson, Davin; Livi, Roberto; Berthomier, Matthieu; Kasper, Justin; Case, Anthony; Stevens, Michael; Bale, Stuart; MacDowall, Robert; Pulupa, Marc; Published by: \apj Published on: sep YEAR: 2022   DOI: 10.3847/1538-4357/ac88c4 Parker Data Used; Solar wind; Space plasmas; Solar corona; Solar magnetic fields; Solar Physics; 1534; 1544; 1483; 1503; 1476 |
Inhomogeneous Kinetic Alfv\ en Waves in the Near-Sun Solar Wind Intervals of intense electromagnetic, broadband plasma waves are reported in the near-Sun solar wind. These waves are identified as kinetic Alfv\ en waves (KAWs), based on comparison between data and theory for their observed electric- to magnetic-field ratio, and magnetic compressibility, as a function of frequency. In contrast to KAW observations at 1 au, KAWs in the near-Sun solar wind are found to be spatially inhomogeneous, preferentially occurring where the ambient magnetic field experiences strong deviations from the ... Malaspina, David; Chasapis, Alexandros; Tatum, Peter; Salem, Chadi; Bale, Stuart; Bonnell, John; de Wit, Thierry; Goetz, Keith; Pulupa, Marc; Halekas, Jasper; Whittlesey, Phyllis; Livi, Roberto; Case, Anthony; Stevens, Michael; Larson, Davin; Published by: \apj Published on: sep YEAR: 2022   DOI: 10.3847/1538-4357/ac87a7 Parker Data Used; Solar wind; Alfven waves; interplanetary turbulence; Space plasmas; Solar magnetic fields; 1534; 23; 830; 1544; 1503 |
Wave emissions at frequencies near electron gyrofrequency harmonics are observed at small heliocentric distances below about 40 R $_\ensuremath\odot$ and are known to occur in regions with quiescent magnetic fields. We show the close connection of these waves to the large-scale properties of the magnetic field. Near electron gyrofrequency harmonic emissions occur only when the ambient magnetic field points to a narrow range of directions bounded by polar and azimuthal angular ranges in the RTN coordinate system of correspond ... Tigik, Sabrina; Vaivads, Andris; Malaspina, David; Bale, Stuart; Published by: \apj Published on: sep YEAR: 2022   DOI: 10.3847/1538-4357/ac8473 Parker Data Used; Space plasmas; Plasma physics; Solar wind; 1544; 2089; 1534; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
Exact laws for evaluating cascade rates, tracing back to the Kolmogorov 4/5 law, have been extended to many systems of interest including magnetohydrodynamics (MHD), and compressible flows of the magnetofluid and ordinary fluid types. It is understood that implementations may be limited by the quantity of available data and by the lack of turbulence symmetry. Assessment of the accuracy and feasibility of such third-order (or Yaglom) relations is most effectively accomplished by examining the von K\ arm\ an-Howarth equati ... Wang, Yanwen; Chhiber, Rohit; Adhikari, Subash; Yang, Yan; Bandyopadhyay, Riddhi; Shay, Michael; Oughton, Sean; Matthaeus, William; Cuesta, Manuel; Published by: \apj Published on: oct YEAR: 2022   DOI: 10.3847/1538-4357/ac8f90 Parker Data Used; interplanetary turbulence; Space plasmas; Plasma physics; Magnetohydrodynamics; Magnetohydrodynamical simulations; 830; 1544; 2089; 1964; 1966; Physics - Space Physics; Physics - Fluid Dynamics; Physics - Plasma Physics |
Zhao, Jinsong; Malaspina, David; de Wit, Dudok; Pierrard, Viviane; Voitenko, Yuriy; Lapenta, Giovanni; Poedts, Stefaan; Bale, Stuart; Kasper, Justin; Larson, Davin; Livi, Roberto; Whittlesey, Phyllis; Published by: \apjl Published on: oct YEAR: 2022   DOI: 10.3847/2041-8213/ac92e3 Parker Data Used; Solar wind; Plasma physics; Space plasmas; 1534; 2089; 1544 |
Observation and Modeling of the Solar Wind Turbulence Evolution in the Sub-Mercury Inner Heliosphere Telloni, Daniele; Adhikari, Laxman; Zank, Gary; Hadid, Lina; anchez-Cano, Beatriz; Sorriso-Valvo, Luca; Zhao, Lingling; Panasenco, Olga; Shi, Chen; Velli, Marco; Susino, Roberto; Verscharen, Daniel; Milillo, Anna; Alberti, Tommaso; Narita, Yasuhito; Verdini, Andrea; Grimani, Catia; Bruno, Roberto; Amicis, Raffaella; Perrone, Denise; Marino, Raffaele; Carbone, Francesco; Califano, Francesco; Malara, Francesco; Stawarz, Julia; Laker, Ronan; Liberatore, Alessandro; Bale, Stuart; Kasper, Justin; Heyner, Daniel; de Wit, Thierry; Goetz, Keith; Harvey, Peter; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Case, Anthony; Korreck, Kelly; Larson, Davin; Livi, Roberto; Stevens, Michael; Whittlesey, Phyllis; Auster, Hans-Ulrich; Richter, Ingo; Published by: \apjl Published on: oct YEAR: 2022   DOI: 10.3847/2041-8213/ac9624 Parker Data Used; Magnetohydrodynamics; Alfven waves; Space plasmas; interplanetary turbulence; Heliosphere; Solar wind; 1964; 23; 1544; 830; 711; 1534 |
Cross-scale Correlations in Imbalanced Solar Wind Turbulence: Parker Solar Probe Observations Zhao, G.~Q.; Meyrand, R.; Feng, H.~Q.; Wu, D.~J.; Kasper, J.~C.; Published by: \apj Published on: oct YEAR: 2022   DOI: 10.3847/1538-4357/ac9380 Parker Data Used; Solar wind; interplanetary turbulence; Solar coronal heating; Space plasmas; Plasma physics; 1534; 830; 1989; 1544; 2089 |
Observations of Quiescent Solar Wind Regions with Near-f $_ce$ Wave Activity In situ measurements in the near-Sun solar wind from the Parker Solar Probe have revealed the existence of quiescent solar wind regions: extended regions of solar wind with low-amplitude turbulent magnetic field fluctuations compared to adjacent regions. Identified through the study of harmonic waves near the electron cyclotron frequency (f $_ce$), these quiescent regions are shown to host a variety of plasma waves. The near-f $_ce$ harmonic waves are observed exclusively in quiescent regions, and as such, they can be used a ... Short, Benjamin; Malaspina, David; Halekas, Jasper; Romeo, Orlando; Verniero, J.~L.; Finley, Adam; Kasper, Justin; Rahmati, Ali; Bale, Stuart; Bonnell, John; Case, Anthony; de Wit, Thierry; Goetz, Keith; Goodrich, Katherine; Harvey, Peter; Korreck, Kelly; Larson, Davin; Livi, Roberto; MacDowall, Robert; Pulupa, Marc; Stevens, Michael; Whittlesey, Phyllis; Published by: \apj Published on: nov YEAR: 2022   DOI: 10.3847/1538-4357/ac97e4 Parker Data Used; Solar wind; interplanetary turbulence; Space plasmas; Solar magnetic fields; Heliosphere; 1534; 830; 1544; 1503; 711 |
We examine statistics of magnetic-field vector components to explore how intermittency evolves from near-Sun plasma to radial distances as large as 10 au. Statistics entering the analysis include autocorrelation, magnetic structure functions of the order of n (SF$_ n $), and scale-dependent kurtosis (SDK), each grouped in ranges of heliocentric distance. The Goddard Space Flight Center Space Physics Data Facility provides magnetic-field measurements for resolutions of 6.8 ms for Parker Solar Probe, 6 s for Helios, and 1.92 s ... Cuesta, Manuel; Parashar, Tulasi; Chhiber, Rohit; Matthaeus, William; Published by: \apjs Published on: mar YEAR: 2022   DOI: 10.3847/1538-4365/ac45fa Parker Data Used; Solar wind; interplanetary magnetic fields; Space plasmas; interplanetary turbulence; Interplanetary physics; 1534; 824; 1544; 830; 827; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics |
We use data from the first six encounters of the Parker Solar Probe and employ the partial variance of increments (PVI) method to study the statistical properties of coherent structures in the inner heliosphere with the aim of exploring physical connections between magnetic field intermittency and observable consequences such as plasma heating and turbulence dissipation. Our results support proton heating localized in the vicinity of, and strongly correlated with, magnetic structures characterized by PVI \ensuremath\geq 1. W ... Sioulas, Nikos; Velli, Marco; Chhiber, Rohit; Vlahos, Loukas; Matthaeus, William; Bandyopadhyay, Riddhi; Cuesta, Manuel; Shi, Chen; Bowen, Trevor; Qudsi, Ramiz; Stevens, Michael; Bale, Stuart; Published by: \apj Published on: mar YEAR: 2022   DOI: 10.3847/1538-4357/ac4fc1 Parker Data Used; Solar wind; Space plasmas; Plasma astrophysics; 1534; 1544; 1261; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
Langmuir-Slow Extraordinary Mode Magnetic Signature Observations with Parker Solar Probe Radio emission from interplanetary shocks, planetary foreshocks, and some solar flares occurs in the so-called plasma emission framework. The generally accepted scenario begins with electrostatic Langmuir waves that are driven by a suprathermal electron beam on the Landau resonance. These Langmuir waves then mode-convert to freely propagating electromagnetic emissions at the local plasma frequency f $_ pe $ and/or its harmonic 2f $_ pe $. However, the details of the physics of mode conversion are unclear, and so far the ... Larosa, A.; de Wit, Dudok; Krasnoselskikh, V.; Bale, S.~D.; Agapitov, O.; Bonnell, J.; Froment, C.; Goetz, K.; Harvey, P.; Halekas, J.; Kretzschmar, M.; MacDowall, R.; Malaspina, David; Moncuquet, M.; Niehof, J.; Pulupa, M.; Revillet, C.; Published by: \apj Published on: mar YEAR: 2022   DOI: 10.3847/1538-4357/ac4e85 Parker Data Used; Solar wind; Plasma physics; Space plasmas; 1534; 2089; 1544 |
We propose a transport theory for the kinetic evolution of solar-wind electrons in the heliosphere. We derive a gyro-averaged kinetic transport equation that accounts for the spherical expansion of the solar wind and the geometry of the Parker spiral magnetic field. To solve our three-dimensional kinetic equation, we develop a mathematical approach that combines the Crank-Nicolson scheme in velocity space and a finite-difference Euler scheme in configuration space. We initialize our model with isotropic electron distribution ... Jeong, Seong-Yeop; Verscharen, Daniel; Vocks, Christian; Abraham, Joel; Owen, Christopher; Wicks, Robert; Fazakerley, Andrew; Stansby, David; Ber\vci\vc, Laura; Nicolaou, Georgios; Rueda, Jeffersson; Bakrania, Mayur; Published by: \apj Published on: mar YEAR: 2022   DOI: 10.3847/1538-4357/ac4805 Parker Data Used; Solar wind; Space plasmas; Heliosphere; Theoretical models; 1534; 1544; 711; 2107; Physics - Space Physics |
The acceleration of charged particles by interplanetary shocks (IPs) can drain a nonnegligible fraction of the plasma pressure. In this study, we have selected 17 IPs observed in situ at 1 au by the Advanced Composition Explorer and the Wind spacecraft, and 1 shock at 0.8 au observed by Parker Solar Probe. We have calculated the time-dependent partial pressure of suprathermal and energetic particles (smaller and greater than 50 keV for protons and 30 keV for electrons, respectively) in both the upstream and downstream region ... David, Liam; Fraschetti, Federico; Giacalone, Joe; Wimmer-Schweingruber, Robert; Berger, Lars; Lario, David; Published by: \apj Published on: mar YEAR: 2022   DOI: 10.3847/1538-4357/ac54af Parker Data Used; Interplanetary shocks; Interplanetary particle acceleration; Space plasmas; 829; 826; 1544; Astrophysics - Solar and Stellar Astrophysics; Astrophysics - High Energy Astrophysical Phenomena; Physics - Plasma Physics; Physics - Space Physics |
The solar wind is a highly turbulent plasma for which the mean rate of energy transfer ɛ has been measured for a long time using the Politano-Pouquet (PP98) exact law. However, this law assumes statistical homogeneity that can be violated by the presence of discontinuities. Here, we introduce a new method based on the inertial dissipation $ D _I^{\sigma }$ whose analytical form is derived from incompressible magnetohydrodynamics; it can be considered as a weak and local (in space) formulation of the PP98 law whose expressio ... David, V.; Galtier, S.; Sahraoui, F.; Hadid, L.~Z.; Published by: \apj Published on: mar YEAR: 2022   DOI: 10.3847/1538-4357/ac524b Parker Data Used; interplanetary turbulence; Space plasmas; Solar wind; 830; 1544; 1534; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
On the Transmission of Turbulent Structures across the Earth s Bow Shock Collisionless shocks and plasma turbulence are crucial ingredients for a broad range of astrophysical systems. The shock-turbulence interaction, and in particular the transmission of fully developed turbulence across the quasi-perpendicular Earth s bow shock, is here addressed using a combination of spacecraft observations and local numerical simulations. An alignment between the Wind (upstream) and Magnetospheric Multiscale (downstream) spacecraft is used to study the transmission of turbulent structures across the shock, r ... Trotta, Domenico; Pecora, Francesco; Settino, Adriana; Perrone, Denise; Hietala, Heli; Horbury, Timothy; Matthaeus, William; Burgess, David; Servidio, Sergio; Valentini, Francesco; Published by: \apj Published on: jul YEAR: 2022   DOI: 10.3847/1538-4357/ac7798 Parker Data Used; Shocks; Space plasmas; interplanetary turbulence; 2086; 1544; 830; Physics - Space Physics |
Density and Velocity Fluctuations of Alpha Particles in Magnetic Switchbacks McManus, Michael; Verniero, Jaye; Bale, Stuart; Bowen, Trevor; Larson, Davin; Kasper, Justin; Livi, Roberto; Matteini, Lorenzo; Rahmati, Ali; Romeo, Orlando; Whittlesey, Phyllis; Woolley, Thomas; Published by: \apj Published on: jul YEAR: 2022   DOI: 10.3847/1538-4357/ac6ba3 Parker Data Used; Heliosphere; Solar wind; Space plasmas; 711; 1534; 1544; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
Taylor Microscale and Effective Reynolds Number near the Sun from PSP The Taylor microscale is a fundamental length scale in turbulent fluids, representing the end of fluid properties and onset of dissipative processes. The Taylor microscale can also be used to evaluate the Reynolds number in classical turbulence theory. Although the solar wind is weakly collisional, it approximately behaves as a magnetohydrodynamic (MHD) fluid at scales larger than the kinetic scale. As a result, classical fluid turbulence theory and formalisms are often used to study turbulence in the MHD range. Therefore, a ... Phillips, C.; Bandyopadhyay, R.; McComas, D.~J.; Published by: \apj Published on: jul YEAR: 2022   DOI: 10.3847/1538-4357/ac713f Parker Data Used; Solar wind; interplanetary turbulence; Magnetohydrodynamics; Space plasmas; 1534; 830; 1964; 1544; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
Clouds of Spacecraft Debris Liberated by Hypervelocity Dust Impacts on Parker Solar Probe Hypervelocity impacts on spacecraft surfaces produce a wide range of effects including transient plasma clouds, surface material ablation, and for some impacts, the liberation of spacecraft material as debris clouds. This study examines debris-producing impacts on the Parker Solar Probe spacecraft as it traverses the densest part of the zodiacal cloud: the inner heliosphere. Hypervelocity impacts by interplanetary dust grains on the spacecraft that produce debris clouds are identified and examined. Impact-generated plasma an ... Malaspina, David; Stenborg, Guillermo; Mehoke, Doug; Al-Ghazwi, Adel; Shen, Mitchell; Hsu, Hsiang-Wen; Iyer, Kaushik; Bale, Stuart; de Wit, Thierry; Published by: \apj Published on: jan YEAR: 2022   DOI: 10.3847/1538-4357/ac3bbb |
Anomalous Cosmic-Ray Oxygen Observations into 0.1 au The Integrated Science Investigation of the Sun instrument suite onboard NASA s Parker Solar Probe mission continues to measure solar energetic particles and cosmic rays closer to the Sun than ever before. Here, we present the first observations of cosmic rays into 0.1 au (21.5 solar radii), focusing specifically on oxygen from \raisebox-0.5ex\textasciitilde2018.7 to \raisebox-0.5ex\textasciitilde2021.2. Our energy spectra reveal an anomalous cosmic-ray-dominated profile that is comparable to that at 1 au, across multiple so ... Rankin, J.~S.; McComas, D.~J.; Leske, R.~A.; Christian, E.~R.; Cohen, C.~M.~S.; Cummings, A.~C.; Joyce, C.~J.; Labrador, A.~W.; Mewaldt, R.~A.; Schwadron, N.~A.; Stone, E.~C.; Strauss, R.~D.; Wiedenbeck, M.~E.; Published by: \apj Published on: jan YEAR: 2022   DOI: 10.3847/1538-4357/ac348f Parker Data Used; 567; 329; 1487; 1193; 1503; 1476; 1534; 96; 1544; 711; 1322; 830; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
Using the Parker Solar Probe FIELDS bandpass-filter data and SWEAP electron data from Encounters 1 through 9, we show statistical properties of narrowband whistlers from \raisebox-0.5ex\textasciitilde16 R $_s$ to \raisebox-0.5ex\textasciitilde130 R $_s$, and compare wave occurrence to electron properties including beta, temperature anisotropy, and heat flux. Whistlers are very rarely observed inside \raisebox-0.5ex\textasciitilde28 R $_s$ (\raisebox-0.5ex\textasciitilde0.13 au). Outside 28 R $_s$, they occur within a narrow ... Cattell, C.; Breneman, A.; Dombeck, J.; Hanson, E.; Johnson, M.; Halekas, J.; Bale, S.~D.; de Wit, Dudok; Goetz, K.; Goodrich, K.; Malaspina, D.; Pulupa, M.; Case, T.; Kasper, J.~C.; Larson, D.; Stevens, M.; Whittlesey, P.; Published by: \apjl Published on: jan YEAR: 2022   DOI: 10.3847/2041-8213/ac4015 Parker Data Used; 1534; 1261; 1544; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
Strong Perpendicular Velocity-space Diffusion in Proton Beams Observed by Parker Solar Probe The SWEAP instrument suite on Parker Solar Probe (PSP) has detected numerous proton beams associated with coherent, circularly polarized, ion-scale waves observed by PSP s FIELDS instrument suite. Measurements during PSP Encounters 4-8 revealed pronounced complex shapes in the proton velocity distribution functions (VDFs), in which the tip of the beam undergoes strong perpendicular diffusion, resulting in VDF level contours that resemble a hammerhead. We refer to these proton beams, with their attendant hammerhead fe ... Verniero, J.~L.; Chandran, B.~D.~G.; Larson, D.~E.; Paulson, K.; Alterman, B.~L.; Badman, S.; Bale, S.~D.; Bonnell, J.~W.; Bowen, T.~A.; de Wit, Dudok; Kasper, J.~C.; Klein, K.~G.; Lichko, E.; Livi, R.; McManus, M.~D.; Rahmati, A.; Verscharen, D.; Walters, J.; Whittlesey, P.~L.; Published by: \apj Published on: jan YEAR: 2022   DOI: 10.3847/1538-4357/ac36d5 Parker Data Used; 1544; 23; 1534; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
Based on the Parker Solar Probe mission, this paper presents the observations of two correlations in solar wind turbulence near the Sun for the first time, demonstrating the clear existence of the following two correlations. One is positive correlation between the proton temperature and turbulent magnetic energy density. The other is negative correlation between the spectral index and magnetic helicity. It is found that the former correlation has a maximum correlation coefficient (CC) at the wavenumber k \ensuremath\rho $_ p ... Zhao, G.~Q.; Lin, Y.; Wang, X.~Y.; Feng, H.~Q.; Wu, D.~J.; Kasper, J.~C.; Published by: \apj Published on: jan YEAR: 2022   DOI: 10.3847/1538-4357/ac3747 |
Simulation of Plasma Emission in Magnetized Plasmas The recent Parker Solar Probe observations of type III radio bursts show that the effects of the finite background magnetic field can be an important factor in the interpretation of data. In the present paper, the effects of the background magnetic field on the plasma-emission process, which is believed to be the main emission mechanism for solar coronal and interplanetary type III radio bursts, are investigated by means of the particle-in-cell simulation method. The effects of the ambient magnetic field are systematically s ... Lee, Sang-Yun; Yoon, Peter; Lee, Ensang; Tu, Weichao; Published by: \apj Published on: jan YEAR: 2022   DOI: 10.3847/1538-4357/ac32bb Parker Data Used; 1544; 1534; Astrophysics - Solar and Stellar Astrophysics |
Slow Shock Formation Upstream of Reconnecting Current Sheets The formation, development, and impact of slow shocks in the upstream regions of reconnecting current layers are explored. Slow shocks have been documented in the upstream regions of magnetohydrodynamic (MHD) simulations of magnetic reconnection as well as in similar simulations with the kglobal kinetic macroscale simulation model. They are therefore a candidate mechanism for preheating the plasma that is injected into the current layers that facilitate magnetic energy release in solar flares. Of particular interest is their ... Arnold, H.; Drake, J.~F.; Swisdak, M.; Guo, F.; Dahlin, J.~T.; Zhang, Q.; Published by: \apj Published on: feb YEAR: 2022   DOI: 10.3847/1538-4357/ac423b Parker Data Used; 1504; 2086; 2089; 1544; Physics - Plasma Physics; Physics - Space Physics |
A Fundamental Instability for the Solar Wind As has been known nearly since the beginning of space research with satellites and rockets that the temperature of the atmosphere of our Sun rises rapidly from the photosphere at about 6000 K to the order of 10$^6$ K. The major heating of the solar wind apparently occurs in a narrow region, the transition region, just above the chromosphere, a region where remote sensing of atomic energy levels shows a temperature of 10$^6$ deg. However, since the early days of the recognition of the solar wind it has been recognized that th ... Published by: \apj Published on: feb YEAR: 2022   DOI: 10.3847/1538-4357/ac32e0 |
Alpha-Proton Differential Flow of the Young Solar Wind: Parker Solar Probe Observations The velocity of alpha particles relative to protons can vary depending on the solar wind type and distance from the Sun. Measurements from the previous spacecraft provided the alpha-proton differential velocities down to 0.3 au. The Parker Solar Probe (PSP) now enables insights into differential flows of the newly accelerated solar wind closer to the Sun for the first time. Here we study the difference between proton and alpha bulk velocities near PSP perihelia of encounters 3-7 when the core solar wind is in the field of vi ... Mostafavi, P.; Allen, R.~C.; McManus, M.~D.; Ho, G.~C.; Raouafi, N.~E.; Larson, D.~E.; Kasper, J.~C.; Bale, S.~D.; Published by: \apjl Published on: feb YEAR: 2022   DOI: 10.3847/2041-8213/ac51e1 Parker Data Used; 1534; 1544; 1492; 1476; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics |
Recent in situ observations from the Parker Solar Probe (PSP) mission in the inner heliosphere near perihelia show evidence of ion beams, temperature anisotropies, and kinetic wave activity, which are likely associated with kinetic heating and acceleration processes of the solar wind. In particular, the proton beams were detected by PSP/Solar Probe Analyzers-Ion (SPAN-I) and related magnetic fluctuation spectra associated with ion-scale waves were observed by the FIELDS instrument. We present the ion velocity distribution fu ... Ofman, Leon; Boardsen, Scott; Jian, Lan; Verniero, Jaye; Larson, Davin; Published by: \apj Published on: feb YEAR: 2022   DOI: 10.3847/1538-4357/ac402c Parker Data Used; 1534; 1545; 1544; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
Using the Parker Solar Probe measurements, this Letter reports two new types of multiband electrostatic waves in and near the heliospheric current sheet. They are classified into the f < f $_ce$ and f > f $_ce$ multiband electrostatic waves, in which most (or all) of the bands in the former type are lower than f $_ce$, and all of the bands in the latter type are higher than f $_ce$, where f and f $_ce$ denotes the wave frequency and the electron cyclotron frequency, respectively. This Letter also exhibits observational evide ... Shi, Chen; Zhao, Jinsong; Malaspina, David; Bale, Stuart; Dong, Xiangcheng; Wang, Tieyan; Wu, Dejin; Published by: \apjl Published on: feb YEAR: 2022   DOI: 10.3847/2041-8213/ac4d37 |
We analyze the micro-kinetic stability of the electron strahl in the solar wind depending on heliocentric distance. The oblique fast- magnetosonic/whistler (FM/W) instability has emerged in the literature as a key candidate mechanism for the effective scattering of the electron strahl into the electron halo population. Using data from the Parker Solar Probe (PSP) and Helios, we compare the measured strahl properties with the analytical thresholds for the oblique FM/W instability in the low- and high-\ensuremath\beta $_\ensur ... Jeong, Seong-Yeop; Abraham, Joel; Verscharen, Daniel; Ber\vci\vc, Laura; Stansby, David; Nicolaou, Georgios; Owen, Christopher; Wicks, Robert; Fazakerley, Andrew; Rueda, Jeffersson; Bakrania, Mayur; Published by: \apjl Published on: feb YEAR: 2022   DOI: 10.3847/2041-8213/ac4dff Parker Data Used; 1534; 1544; 711; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
In the lower solar coronal regions where the magnetic field is dominant, the Alfv\ en speed is much higher than the wind speed. In contrast, the near-Earth solar wind is strongly super- Alfv\ enic, i.e., the wind speed greatly exceeds the Alfv\ en speed. The transition between these regimes is classically described as the Alfv\ en point but may in fact occur in a distributed Alfv\ en critical region. NASA s Parker Solar Probe (PSP) mission has entered this region, as it follows a series of orbits that gradually approach ... Bandyopadhyay, R.; Matthaeus, W.~H.; McComas, D.~J.; Chhiber, R.; Usmanov, A.~V.; Huang, J.; Livi, R.; Larson, D.~E.; Kasper, J.~C.; Case, A.~W.; Stevens, M.; Whittlesey, P.; Romeo, O.~M.; Bale, S.~D.; Bonnell, J.~W.; de Wit, Dudok; Goetz, K.; Harvey, P.~R.; MacDowall, R.~J.; Malaspina, D.~M.; Pulupa, M.; Published by: \apjl Published on: feb YEAR: 2022   DOI: 10.3847/2041-8213/ac4a5c Parker Data Used; 1544; 1534; 824; 23; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics |
Parker Solar Probe (PSP) and SolO data are utilized to investigate magnetic field intermittency in the solar wind (SW). Small-scale intermittency (20-100 d $_ i $) is observed to radially strengthen when methods relying on higher-order moments are considered (SF$_ q $; SDK), but no clear trend is observed at larger scales. However, lower-order moment-based methods (e.g., partial variance of increments; PVI) are deemed more appropriate for examining the evolution of the bulk of coherent structures (CSs), PVI \ensuremath\geq 3 ... Sioulas, Nikos; Huang, Zesen; Velli, Marco; Chhiber, Rohit; Cuesta, Manuel; Shi, Chen; Matthaeus, William; Bandyopadhyay, Riddhi; Vlahos, Loukas; Bowen, Trevor; Qudsi, Ramiz; Bale, Stuart; Owen, Christopher; Louarn, P.; Fedorov, A.; c, Milan; Stevens, Michael; Case, Anthony; Kasper, Justin; Larson, Davin; Pulupa, Marc; Livi, Roberto; Published by: \apj Published on: aug YEAR: 2022   DOI: 10.3847/1538-4357/ac7aa2 Parker Data Used; Solar wind; interplanetary turbulence; Magnetohydrodynamics; Space plasmas; Plasma astrophysics; Solar Physics; 1534; 830; 1964; 1544; 1261; 1476; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
The solar wind measured in situ by Parker Solar Probe in the very inner heliosphere is studied in combination with the remote-sensing observation of the coronal source region provided by the METIS coronagraph aboard Solar Orbiter. The coronal outflows observed near the ecliptic by Metis on 2021 January 17 at 16:30 UT, between 3.5 and 6.3 R $_\ensuremath\odot$ above the eastern solar limb, can be associated with the streams sampled by PSP at 0.11 and 0.26 au from the Sun, in two time intervals almost 5 days apart. The two pla ... Telloni, Daniele; Zank, Gary; Sorriso-Valvo, Luca; Amicis, Raffaella; Panasenco, Olga; Susino, Roberto; Bruno, Roberto; Perrone, Denise; Adhikari, Laxman; Liang, Haoming; Nakanotani, Masaru; Zhao, Lingling; Hadid, Lina; anchez-Cano, Beatriz; Verscharen, Daniel; Velli, Marco; Grimani, Catia; Marino, Raffaele; Carbone, Francesco; Mancuso, Salvatore; Biondo, Ruggero; Pagano, Paolo; Reale, Fabio; Bale, Stuart; Kasper, Justin; Case, Anthony; de Wit, Thierry; Goetz, Keith; Harvey, Peter; Korreck, Kelly; Larson, Davin; Livi, Roberto; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Stevens, Michael; Whittlesey, Phyllis; Romoli, Marco; Andretta, Vincenzo; Da Deppo, Vania; Fineschi, Silvano; Heinzel, Petr; Moses, John; Naletto, Giampiero; Nicolini, Gianalfredo; Spadaro, Daniele; Stangalini, Marco; Teriaca, Luca; Capobianco, Gerardo; Capuano, Giuseppe; Casini, Chiara; Casti, Marta; Chioetto, Paolo; Corso, Alain; De Leo, Yara; Fabi, Michele; Frassati, Federica; Frassetto, Fabio; Giordano, Silvio; Guglielmino, Salvo; Jerse, Giovanna; Landini, Federico; Liberatore, Alessandro; Magli, Enrico; Massone, Giuseppe; Messerotti, Mauro; Pancrazzi, Maurizio; Pelizzo, Maria; Romano, Paolo; Sasso, Clementina; Schühle, Udo; Slemer, Alessandra; Straus, Thomas; Uslenghi, Michela; Volpicelli, Cosimo; Zangrilli, Luca; Zuppella, Paola; Abbo, Lucia; Auchère, Fr\; Cuadrado, Regina; Berlicki, Arkadiusz; Ciaravella, Angela; Lamy, Philippe; Lanzafame, Alessandro; Malvezzi, Marco; Nicolosi, Piergiorgio; o, Giuseppe; Peter, Hardi; Solanki, Sami; Strachan, Leonard; Tsinganos, Kanaris; Ventura, Rita; Vial, Jean-Claude; Woch, Joachim; Zimbardo, Gaetano; Published by: \apj Published on: aug YEAR: 2022   DOI: 10.3847/1538-4357/ac8103 Parker Data Used; H II regions; Alfven waves; Space plasmas; interplanetary turbulence; Solar corona; Heliosphere; Solar wind; 694; 23; 1544; 830; 1483; 711; 1534 |
Markovian Features of the Solar Wind at Subproton Scales The interplanetary magnetic field carried out from the Sun by the solar wind displays fluctuations over a wide range of scales. While at large scales, say at frequencies lower than 0.1-1 Hz, fluctuations display the universal character of fully developed turbulence with a well-defined Kolmogorov-like inertial range, the physical and dynamical properties of the small-scale regime as well as their connection with the large-scale ones are still a debated topic. In this work we investigate the near-Sun magnetic field fluctuation ... Benella, Simone; Stumpo, Mirko; Consolini, Giuseppe; Alberti, Tommaso; Carbone, Vincenzo; Laurenza, Monica; Published by: \apjl Published on: apr YEAR: 2022   DOI: 10.3847/2041-8213/ac6107 Parker Data Used; Solar wind; interplanetary turbulence; Magnetohydrodynamics; Heliosphere; Interplanetary physics; Space plasmas; 1534; 830; 1964; 711; 827; 1544; Physics - Space Physics; Physics - Data Analysis; Statistics and Probability; Physics - Plasma Physics |
Using the Parker Solar Probe data taken in the inner heliosphere, we investigate the power and spatial anisotropy of magnetic field spectra at kinetic scales (i.e., around sub-ion scales) in solar wind turbulence in the inner heliosphere. We find that strong anisotropy of the magnetic spectra occurs at kinetic scales with the strongest power in the perpendicular direction with respect to the local magnetic field (forming an angle \ensuremath\theta $_B$ with the mean flow velocity). The spectral index of the magnetic spectra ... Huang, S.~Y.; Xu, S.~B.; Zhang, J.; Sahraoui, F.; es, Andr\; He, J.~S.; Yuan, Z.~G.; Deng, X.~H.; Jiang, K.; Wei, Y.~Y.; Xiong, Q.~Y.; Wang, Z.; Yu, L.; Lin, R.~T.; Published by: \apjl Published on: apr YEAR: 2022   DOI: 10.3847/2041-8213/ac5f02 Parker Data Used; Solar wind; interplanetary turbulence; Heliosphere; Space plasmas; 1534; 830; 711; 1544; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
2021 |
On the Origin of Switchbacks Observed in the Solar Wind The origin of switchbacks in the solar wind is discussed in two classes of theory that differ in the location of the source being either near the transition region near the Sun or in the solar wind itself. The two classes of theory differ in their predictions of the switchback rate (the number of switchbacks observed per hour) as a function of distance from the Sun. To distinguish between these theories, one-hour averages of Parker Solar Probe data were averaged over five orbits to find the following: (1) The hourly averaged ... Mozer, F.~S.; Bale, S.~D.; Bonnell, J.~W.; Drake, J.~F.; Hanson, E.~L.~M.; Mozer, M.~C.; Published by: \apj Published on: sep YEAR: 2021   DOI: 10.3847/1538-4357/ac110d Solar wind; Solar corona; Space plasmas; 1534; 1483; 1544; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics; Parker Data Used |
The role of solar wind expansion in generating whistler waves is investigated using the EB-iPic3D code, which models solar wind expansion self-consistently within a fully kinetic semi-implicit approach. The simulation is initialized with an electron velocity distribution function modeled after observations of the Parker Solar Probe during its first perihelion at 0.166 au, consisting of a dense core and an antisunward strahl. This distribution function is initially stable with respect to kinetic instabilities. Expansion drive ... Micera, A.; Zhukov, A.~N.; opez, R.~A.; Boella, E.; Tenerani, A.; Velli, M.; Lapenta, G.; Innocenti, M.~E.; Published by: \apj Published on: sep YEAR: 2021   DOI: 10.3847/1538-4357/ac1067 Solar wind; Plasma astrophysics; Space plasmas; 1534; 1261; 1544; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics; Parker Data Used |
Motivated by recent Parker Solar Probe (PSP) observations of switchbacks (abrupt, large-amplitude reversals in the radial magnetic field, which exhibit Alfv\ enic correlations), we examine the dynamics of large-amplitude Alfv\ en waves in the expanding solar wind. We develop an analytic model that makes several predictions: switchbacks should preferentially occur in regions where the solar wind plasma has undergone a greater expansion, the switchback fraction at radii comparable to PSP should be an increasing function of ... Mallet, Alfred; Squire, Jonathan; Chandran, Benjamin; Bowen, Trevor; Bale, Stuart; Published by: \apj Published on: sep YEAR: 2021   DOI: 10.3847/1538-4357/ac0c12 Alfven waves; Magnetohydrodynamics; Solar wind; Space plasmas; 23; 1964; 1534; 1544; Parker Data Used |
This Letter addresses the first Solar Orbiter (SO)-Parker Solar Probe (PSP) quadrature, occurring on 2021 January 18 to investigate the evolution of solar wind from the extended corona to the inner heliosphere. Assuming ballistic propagation, the same plasma volume observed remotely in the corona at altitudes between 3.5 and 6.3 solar radii above the solar limb with the Metis coronagraph on SO can be tracked to PSP, orbiting at 0.1 au, thus allowing the local properties of the solar wind to be linked to the coronal source re ... Telloni, Daniele; Andretta, Vincenzo; Antonucci, Ester; Bemporad, Alessandro; Capuano, Giuseppe; Fineschi, Silvano; Giordano, Silvio; Habbal, Shadia; Perrone, Denise; Pinto, Rui; Sorriso-Valvo, Luca; Spadaro, Daniele; Susino, Roberto; Woodham, Lloyd; Zank, Gary; Romoli, Marco; Bale, Stuart; Kasper, Justin; Auchère, Fr\; Bruno, Roberto; Capobianco, Gerardo; Case, Anthony; Casini, Chiara; Casti, Marta; Chioetto, Paolo; Corso, Alain; Da Deppo, Vania; De Leo, Yara; de Wit, Thierry; Frassati, Federica; Frassetto, Fabio; Goetz, Keith; Guglielmino, Salvo; Harvey, Peter; Heinzel, Petr; Jerse, Giovanna; Korreck, Kelly; Landini, Federico; Larson, Davin; Liberatore, Alessandro; Livi, Roberto; MacDowall, Robert; Magli, Enrico; Malaspina, David; Massone, Giuseppe; Messerotti, Mauro; Moses, John; Naletto, Giampiero; Nicolini, Gianalfredo; o, Giuseppe; Panasenco, Olga; Pancrazzi, Maurizio; Pelizzo, Maria; Pulupa, Marc; Reale, Fabio; Romano, Paolo; Sasso, Clementina; Schühle, Udo; Stangalini, Marco; Stevens, Michael; Strachan, Leonard; Straus, Thomas; Teriaca, Luca; Uslenghi, Michela; Velli, Marco; Verscharen, Daniel; Volpicelli, Cosimo; Whittlesey, Phyllis; Zangrilli, Luca; Zimbardo, Gaetano; Zuppella, Paola; Published by: \apjl Published on: oct YEAR: 2021   DOI: 10.3847/2041-8213/ac282f Parker Data Used; Magnetohydrodynamics; Space plasmas; interplanetary turbulence; Solar corona; Heliosphere; Solar wind; 1964; 1544; 830; 1483; 711; 1534; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
Evolution of Switchbacks in the Inner Heliosphere We analyze magnetic field data from the first six encounters of Parker Solar Probe, three Helios fast streams and two Ulysses south polar passes covering heliocentric distances 0.1 \ensuremath\lesssim R \ensuremath\lesssim 3 au. We use this data set to statistically determine the evolution of switchbacks of different periods and amplitudes with distance from the Sun. We compare the radial evolution of magnetic field variances with that of the mean square amplitudes of switchbacks, and quantify the radial evolution of the cum ... Tenerani, Anna; Sioulas, Nikos; Matteini, Lorenzo; Panasenco, Olga; Shi, Chen; Velli, Marco; Published by: \apjl Published on: oct YEAR: 2021   DOI: 10.3847/2041-8213/ac2606 Parker Data Used; Heliosphere; Solar wind; interplanetary turbulence; Alfven waves; Space plasmas; 711; 1534; 830; 23; 1544; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
The solar wind escapes from the solar corona and is accelerated, over a short distance, to its terminal velocity. The energy balance associated with this acceleration remains poorly understood. To quantify the global electrostatic contribution to the solar wind dynamics, we empirically estimate the ambipolar electric field (E$_\ensuremath\parallel$) and potential (\ensuremath\Phi$_r,\ensuremath\infty$). We analyze electron velocity distribution functions (VDFs) measured in the near-Sun solar wind between 20.3 R$_S$ and 85.3 ... Ber\vci\vc, Laura; c, Milan; Halekas, Jasper; Landi, Simone; Owen, Christopher; Verscharen, Daniel; Larson, Davin; Whittlesey, Phyllis; Badman, Samuel; Bale, Stuart.; Case, Anthony; Goetz, Keith; Harvey, Peter; Kasper, Justin; Korreck, Kelly; Livi, Roberto; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Stevens, Michael; Published by: \apj Published on: nov YEAR: 2021   DOI: 10.3847/1538-4357/ac1f1c Parker Data Used; Solar wind; Space plasmas; Interplanetary particle acceleration; Collision processes; Space vehicle instruments; 1534; 1544; 826; 2065; 1548; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
Turbulent Generation of Magnetic Switchbacks in the Alfv\ enic Solar Wind One of the most important early results from the Parker Solar Probe (PSP) is the ubiquitous presence of magnetic switchbacks, whose origin is under debate. Using a three-dimensional direct numerical simulation of the equations of compressible magnetohydrodynamics from the corona to 40 solar radii, we investigate whether magnetic switchbacks emerge from granulation-driven Alfv\ en waves and turbulence in the solar wind. The simulated solar wind is an Alfv\ enic slow-solar- wind stream with a radial profile consistent with var ... Shoda, Munehito; Chandran, Benjamin; Cranmer, Steven; Published by: \apj Published on: jul YEAR: 2021   DOI: 10.3847/1538-4357/abfdbc Space plasmas; Solar wind; interplanetary turbulence; Parker Data Used; Magnetohydrodynamical simulations; Alfven waves; 1544; 1534; 830; 1966; 23; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics |
We report analysis of sub-Alfv\ enic magnetohydrodynamic (MHD) perturbations in the low-\ensuremath\beta radial-field solar wind employing the Parker Solar Probe spacecraft data from 2018 October 31 to November 12. We calculate wavevectors using the singular value decomposition method and separate MHD perturbations into three eigenmodes (Alfv\ en, fast, and slow modes) to explore the properties of sub-Alfv\ enic perturbations and the role of compressible perturbations in solar wind heating. The MHD perturbations show a high ... Zhao, S.~Q.; Yan, Huirong; Liu, Terry; Liu, Mingzhe; Shi, Mijie; Published by: \apj Published on: dec YEAR: 2021   DOI: 10.3847/1538-4357/ac2ffe Parker Data Used; 1534; 830; 1964; 1544; 1636; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
Domains of Magnetic Pressure Balance in Parker Solar Probe Observations of the Solar Wind The Parker Solar Probe (PSP) spacecraft is performing the first in situ exploration of the solar wind within 0.2 au of the Sun. Initial observations confirmed the Alfv\ enic nature of aligned fluctuations of the magnetic field B and velocity V in solar wind plasma close to the Sun, in domains of nearly constant magnetic field magnitude \ensuremath\mid B \ensuremath\mid, i.e., approximate magnetic pressure balance. Such domains are interrupted by particularly strong fluctuations, including but not limited to radial field (pol ... Ruffolo, David; Ngampoopun, Nawin; Bhora, Yash; Thepthong, Panisara; Pongkitiwanichakul, Peera; Matthaeus, William; Chhiber, Rohit; Published by: \apj Published on: dec YEAR: 2021   DOI: 10.3847/1538-4357/ac2ee3 Parker Data Used; 1534; 830; 1544; 824; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
Interaction between Multiple Current Sheets and a Shock Wave: 2D Hybrid Kinetic Simulations Particle acceleration behind a shock wave due to interactions between magnetic islands in the heliosphere has attracted attention in recent years. The downstream acceleration may yield a continuous increase of particle flux downstream of the shock wave. Although it is not obvious how the downstream magnetic islands are produced, it has been suggested that current sheets are involved in the generation of magnetic islands due to their interaction with a shock wave. We perform 2D hybrid kinetic simulations to investigate the in ... Nakanotani, M.; Zank, G.~P.; Zhao, L.; Published by: \apj Published on: dec YEAR: 2021   DOI: 10.3847/1538-4357/ac2e06 |
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 |
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 |
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 |
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 |
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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