Found 126 entries in the Bibliography.
Showing entries from 1 through 50
| 2020 |
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Shear-driven Transition to Isotropically Turbulent Solar Wind Outside the Alfv\ en Critical Zone Motivated by prior remote observations of a transition from striated\ solar\ coronal structures to more isotropic "flocculated" fluctuations, we propose that the dynamics of the inner\ solar\ wind just outside the Alfven critical zone, and in the vicinity of the first beta = 1 surface, is powered by the relative velocities of adjacent coronal magnetic flux tubes. We suggest that large-amplitude flow contrasts are magnetically constrained at lower altitude but shear-driven dynamics are triggered as such ... Ruffolo, D.; Matthaeus, W.; Chhiber, R.; Usmanov, A.; Yang, Y.; Bandyopadhyay, R.; Parashar, T.; Goldstein, M.; DeForest, C.; Wan, M.; Chasapis, A.; Maruca, B.; Velli, M.; Kasper, J.; YEAR: 2020 DOI: 10.3847/1538-4357/abb594 |
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Small Electron Events Observed by Parker Solar Probe/IS⊙IS during Encounter 2 The current understanding of the characteristics of\ solar\ and inner heliospheric electron events is inferred almost entirely from observations made by spacecraft located at 1 astronomical unit (au). Previous observations within 1 au of the Sun, by the Helios spacecraft at similar to 0.3-1 au, indicate the presence of electron events that are not detected at 1 au or may have merged during transport from the Sun.\ Parker\ Solar\ Probe\textquoterights close proximity to the Sun at perihelion provid ... Mitchell, J.; de Nolfo, G.; Hill, M.; Christian, E.; McComas, D.; Schwadron, N.; Wiedenbeck, M.; Bale, S.; Case, A.; Cohen, C.; Joyce, C.; Kasper, J.; Labrador, A.; Leske, R.; MacDowall, R.; Mewaldt, R.; Mitchell, D.; Pulupa, M.; Richardson, I.; Stevens, M.; Szalay, J.; YEAR: 2020 DOI: 10.3847/1538-4357/abb2a4 Parker Data Used; parker solar probe; Radio bursts; Solar energetic particles; solar flares; Solar particle emission; Solar Physics; Solar Probe Plus |
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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.; YEAR: 2020 DOI: 10.3847/1538-4357/abb132 |
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The Solar Wind Angular Momentum Flux as Observed by Parker Solar Probe he long-term evolution of the Sun\textquoterights rotation period cannot be directly observed, and is instead inferred from trends in the measured rotation periods of other Sun-like stars. Assuming the Sun spins down as it ages, following rotation rate proportional to age(-1/2), requires the current\ solar\ angular momentum (AM) loss rate to be around 6 x 10(30)erg. Magnetohydrodynamic models, and previous observations of the\ solar\ wind (from the Helios and Wind spacecraft), generally predict a value ... Finley, Adam; Matt, Sean; eville, Victor; Pinto, Rui; Owens, Mathew; Kasper, Justin; Korreck, Kelly; Case, A.; Stevens, Michael; Whittlesey, Phyllis; Larson, Davin; Livi, Roberto; YEAR: 2020 DOI: 10.3847/2041-8213/abb9a5 Parker Data Used; parker solar probe; Solar evolution; Solar Physics; Solar Probe Plus; Solar rotation; Solar wind; Stellar evolution; Stellar physics; Stellar rotation |
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Large-amplitude, Wideband, Doppler-shifted, Ion Acoustic Waves Observed on the Parker Solar Probe Electric field spectra measured on the\ Parker\ Solar\ Probe\ typically contain upwards of 1000 large-amplitude (similar to 15 mV m(-1)), wideband (similar to 100-15,000 Hz), few-second-duration, electric field waveforms per day. The satellite also collected about 85 three-second bursts of electric field waveforms per day at a data rate of similar to 150,000 samples per second. Eight such bursts caught these waves, all of which were located in switchbacks of the magnetic field. A wave burst on 2019 Sep ... Mozer, F.; Bonnell, J.; Bowen, T.; Schumm, G.; . Y. Vasko, I; YEAR: 2020 DOI: 10.3847/1538-4357/abafb4 Parker Data Used; parker solar probe; Solar Probe Plus; Solar wind |
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On the Scaling Properties of Magnetic-field Fluctuations through the Inner Heliosphere Although the interplanetary magnetic-field variability has been extensively investigated in situ using data from several space missions, newly launched missions providing high-resolution measures and approaching the Sun offer the possibility to study the multiscale variability in the innermost\ solar\ system. Here, using\ Parker\ Solar\ Probe\ measurements, we investigate the scaling properties of\ solar\ wind magnetic-field fluctuations at different heliocentric distances. The resu ... Alberti, Tommaso; Laurenza, Monica; Consolini, Giuseppe; Milillo, Anna; Marcucci, Maria; Carbone, Vincenzo; Bale, Stuart; YEAR: 2020 DOI: 10.3847/1538-4357/abb3d2 Chaos; interplanetary magnetic fields; interplanetary turbulence; Parker Data Used; parker solar probe; Solar Probe Plus; Solar wind; Time series analysis |
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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.; 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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Turbulence, a ubiquitous phenomenon in interplanetary space, is crucial for the energy conversion of space plasma at multiple scales. This work focuses on the propagation, polarization, and wave composition properties of the\ solar\ wind turbulence within 0.3 au, and its variation with heliocentric distance at magnetohydrodynamic scales (from 10 s to 1000 s in the spacecraft frame). We present the probability density function of propagation wavevectors (PDF (k(parallel to),k)) for\ solar\ wind turbulen ... Zhu, Xingyu; He, Jiansen; Verscharen, Daniel; Duan, Die; Bale, Stuart; YEAR: 2020 DOI: 10.3847/2041-8213/abb23e Alfv\ en waves; Heliosphere; interplanetary turbulence; Parker Data Used; parker solar probe; Slow solar wind; Solar Probe Plus |
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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.; 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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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; 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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The Solar Origin of Particle Events Measured by Parker Solar Probe During the second solar encounter phase of Parker Solar Probe (PSP), two small solar energetic particle (SEP) events were observed by the Integrated Science Investigation of the Sun, on 2019 April 2 and 4. At the time, PSP was approaching its second perihelion at a distance of \~24.8 million kilometers from the solar center, it was in near-radial alignment with STEREO-A and in quadrature with Earth. During the two SEP events multiple narrow ejections and a streamer-blowout coronal mass ejection (SBO-CME) originated from a ... Kouloumvakos, Athanasios; Vourlidas, Angelos; Rouillard, Alexis; Roelof, Edmond; Leske, Rick; Pinto, Rui; Poirier, Nicolas; YEAR: 2020 DOI: 10.3847/1538-4357/aba5a1 Parker Data Used; parker solar probe; Solar coronal mass ejection shocks; Solar coronal mass ejections; Solar energetic particles; Solar particle emission; Solar Probe Plus |
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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.; 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 Electromagnetic Signature of Outward Propagating Ion-scale Waves First results from the Parker Solar Probe (PSP) mission have revealed ubiquitous coherent ion-scale waves in the inner heliosphere, which are signatures of kinetic wave-particle interactions and fluid instabilities. However, initial studies of the circularly polarized ion-scale waves observed by PSP have only thoroughly analyzed magnetic field signatures, precluding a determination of solar wind frame propagation direction and intrinsic wave polarization. A comprehensive determination of wave properties requires measureme ... Bowen, Trevor; Bale, Stuart; Bonnell, J.; Larson, Davin; Mallet, Alfred; McManus, Michael; Mozer, Forrest; Pulupa, Marc; Vasko, Ivan; Verniero, J.; YEAR: 2020 DOI: 10.3847/1538-4357/ab9f37 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Plasma astrophysics; Plasma physics; Solar Probe Plus; Solar wind; Space plasmas |
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Magnetic Field Dropouts at Near-Sun Switchback Boundaries: A Superposed Epoch Analysis During Parker Solar Probe\textquoterights first close encounter with the Sun in early 2018 November, a large number of impulsive rotations in the magnetic field were detected within 50 Rs; these also occurred in association with short-lived impulsive solar wind bursts in speed. These impulsive features are now called "switchback" events. We examined a set of these switchbacks where the boundary transition into and out of the switchback was abrupt, with fast B rotations and simultaneous solar wind speed changes ... Farrell, W.; MacDowall, R.; Gruesbeck, J.; Bale, S.; Kasper, J.; YEAR: 2020 DOI: 10.3847/1538-4365/ab9eba Parker Data Used; parker solar probe; Solar Physics; Solar Probe Plus; Solar wind; The Sun |
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The distribution of spacecraft in the inner heliosphere during 2019 March enabled comprehensive observations of an interplanetary coronal mass ejection (ICME) that encountered Parker Solar Probe (PSP) at 0.547 au from the Sun. This ICME originated as a slow (\~311 km s-1) streamer blowout (SBO) on the Sun as measured by the white-light coronagraphs on board the Solar TErrestrial RElations Observatory-A and the Solar and Heliospheric Observatory. Despite its low initial speed, the passage of the ICME at PSP was ... Lario, D.; Balmaceda, L.; Alzate, N.; Mays, M.; Richardson, I.; Allen, R.; Florido-Llinas, M.; Nieves-Chinchilla, T.; Koval, A.; Lugaz, N.; Jian, L.; Arge, C.; Macneice, P.; Odstrcil, D.; Morgan, H.; Szabo, A.; Desai, M.; Whittlesey, P.; Stevens, M.; Ho, G.; Luhmann, J.; YEAR: 2020 DOI: 10.3847/1538-4357/ab9942 |
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Constraining Ion-Scale Heating and Spectral Energy Transfer in Observations of Plasma Turbulence We perform a statistical study of the turbulent power spectrum at inertial and kinetic scales observed during the first perihelion encounter of the Parker Solar Probe. We find that often there is an extremely steep scaling range of the power spectrum just above the ion-kinetic scales, similar to prior observations at 1 A.U., with a power-law index of around -4 . Based on our measurements, we demonstrate that either a significant (\>50 \%) fraction of the total turbulent energy flux is dissipated in this range of scales ... Bowen, Trevor; Mallet, Alfred; Bale, Stuart; Bonnell, J.; Case, Anthony; Chandran, Benjamin; Chasapis, Alexandros; Chen, Christopher; Duan, Die; de Wit, Thierry; Goetz, Keith; Halekas, Jasper; Harvey, Peter; Kasper, J.; Korreck, Kelly; Larson, Davin; Livi, Roberto; MacDowall, Robert; Malaspina, David; McManus, Michael; Pulupa, Marc; Stevens, Michael; Whittlesey, Phyllis; YEAR: 2020 DOI: 10.1103/PhysRevLett.125.025102 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
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Editorial: Solar Wind at the Dawn of the Parker Solar Probe and Solar Orbiter Era Solar Wind 15 brought together almost 250 experts from all continents of the world to discuss the current trends and future perspectives of the research on the Sun and its solar wind. The present article collection recaptures some of the highlights of their contributions. Lapenta, Giovanni; Zhukov, Andrei; van Driel-Gesztelyi, Lidia; YEAR: 2020 DOI: 10.1007/s11207-020-01670-8 Parker Data Used; parker solar probe; Solar Probe Plus; Solar wind |
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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 ... . Y. Huang, S; Zhang, J.; Sahraoui, F.; He, J.; Yuan, Z.; es, Andr\; Hadid, L.; Deng, X.; Jiang, K.; Yu, L.; . Y. Xiong, Q; . Y. Wei, Y; Xu, S.; Bale, S.; Kasper, J.; 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; YEAR: 2020 DOI: 10.3847/1538-4357/ab97b3 Parker Data Used; parker solar probe; Solar energetic particles; Solar Probe Plus |
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(Non)radial Solar Wind Propagation through the Heliosphere The solar wind nonradial velocity components observed beyond the Alfv\ en point are usually attributed to waves, the interaction of different streams, or other transient phenomena. However, Earth-orbiting spacecraft as well as monitors at L1 indicate systematic deviations of the wind velocity from the radial direction. Since these deviations are of the order of several degrees, the calibration of the instruments is often questioned. This paper investigates for the first time the evolution of nonradial components of the so ... cek, Zden\v; a, Tereza; a, Jana; Richardson, John; Simůnek, Jiř\; Stevens, Michael; YEAR: 2020 DOI: 10.3847/2041-8213/ab9ff7 |
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Coronal-jet-producing Minifilament Eruptions as a Possible Source of Parker Solar Probe Switchbacks The Parker Solar Probe (PSP) has observed copious rapid magnetic field direction changes in the near-Sun solar wind. These features have been called "switchbacks," and their origin is a mystery. But their widespread nature suggests that they may be generated by a frequently occurring process in the Sun\textquoterights atmosphere. We examine the possibility that the switchbacks originate from coronal jets. Recent work suggests that many coronal jets result when photospheric magnetic flux cancels, and forms a small-scale "m ... Sterling, Alphonse; Moore, Ronald; YEAR: 2020 DOI: 10.3847/2041-8213/ab96be 1503; 1504; 1534; 1981; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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Global Circulation of the Open Magnetic Flux of the Sun The global circulation of the open magnetic flux of the Sun, the component of the solar magnetic field that opens into the heliosphere, and the consequences of the global circulation were proposed by Fisk and coworkers in the early 2000s. The Parker Solar Probe, on its initial encounters with the Sun, has provided direct confirmation of both the global circulation and the physical mechanism by which the circulation occurs, transport by interchange reconnection between open magnetic flux and large coronal loops. The implic ... YEAR: 2020 DOI: 10.3847/2041-8213/ab8acd |
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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.; YEAR: 2020 DOI: 10.3847/2041-8213/ab8d2d |
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A Merged Search-Coil and Fluxgate Magnetometer Data Product for Parker Solar Probe FIELDS NASA\textquoterights Parker Solar Probe (PSP) mission is currently investigating the local plasma environment of the inner heliosphere (\<0.25 R☉) using both in situ and remote sensing instrumentation. Connecting signatures of microphysical particle heating and acceleration processes to macroscale heliospheric structure requires sensitive measurements of electromagnetic fields over a large range of physical scales. The FIELDS instrument, which provides PSP with in situ measurements of electromagnetic field ... Bowen, T.; Bale, S.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Goodrich, K.; Gruesbeck, J.; Harvey, P.; Jannet, G.; Koval, A.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Revillet, C.; Sheppard, D.; Szabo, A.; YEAR: 2020 DOI: 10.1029/2020JA027813 Astrophysics - Instrumentation and Methods for Astrophysics; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Instrumentation and Detectors; Physics - Space Physics; Solar Probe Plus |
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Parker Solar Probe Observations of Proton Beams Simultaneous with Ion-scale Waves Parker Solar Probe (PSP), NASA\textquoterights latest and closest mission to the Sun, is on a journey to investigate fundamental enigmas of the inner heliosphere. This paper reports initial observations made by the Solar Probe Analyzer for Ions (SPAN-I), one of the instruments in the Solar Wind Electrons Alphas and Protons instrument suite. We address the presence of secondary proton beams in concert with ion-scale waves observed by FIELDS, the electromagnetic fields instrument suite. We show two events from PSP\textquote ... Verniero, J.; Larson, D.; Livi, R.; Rahmati, A.; McManus, M.; Pyakurel, Sharma; Klein, K.; Bowen, T.; Bonnell, J.; Alterman, B.; Whittlesey, P.; Malaspina, David; Bale, S.; Kasper, J.; Case, A.; Goetz, K.; Harvey, P.; Korreck, K.; MacDowall, R.; Pulupa, M.; Stevens, M.; de Wit, Dudok; YEAR: 2020 DOI: 10.3847/1538-4365/ab86af Alfv\ en waves; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Plasma physics; Solar Probe Plus; Solar wind; Space plasmas |
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The Wide-field Imager for Parker Solar Probe (WISPR) captures unprecedented white-light images of the solar corona and inner heliosphere. Thanks to the uniqueness of the Parker Solar Probe\textquoterights (PSP) orbit, WISPR is able to image "locally" coronal structures at high spatial and time resolutions. The observed plane of sky, however, rapidly changes because of the PSP\textquoterights high orbital speed. Therefore, the interpretation of the dynamics of the coronal structures recorded by WISPR is not straightforward ... o, Giuseppe; Bothmer, Volker; Vourlidas, Angelos; Liewer, Paulett; Thernisien, Arnaud; Stenborg, Guillermo; Howard, Russell; YEAR: 2020 DOI: 10.1007/s11207-020-01626-y Astrophysics - Solar and Stellar Astrophysics; Corona; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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The Width, Density, and Outflow of Solar Coronal Streamers Characterizing the large-scale structure and plasma properties of the inner corona is crucial to understanding the source and subsequent expansion of the solar wind and related space weather effects. Here, we apply a new coronal rotational tomography method, along with a method to narrow streamers and refine the density estimate, to COR2A/Solar Terrestrial Relations Observatory observations from a period near solar minimum and maximum, gaining density maps for heights between 4 and 8R☉. The coronal structure ... YEAR: 2020 DOI: 10.3847/1538-4357/ab7e32 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Solar Probe Plus |
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The shape of the electron velocity distribution function plays an important role in the dynamics of the solar wind acceleration. Electrons are normally modeled with three components, the core, the halo, and the strahl. We investigate how well the fast strahl electrons in the inner heliosphere preserve the information about the coronal electron temperature at their origin. We analyzed the data obtained by two missions, Helios, spanning the distances between 65 and 215 RS, and Parker Solar Probe (PSP), reaching d ... c, Laura; Larson, Davin; Whittlesey, Phyllis; Maksimovic, Milan; Badman, Samuel; Landi, Simone; Matteini, Lorenzo; Bale, Stuart.; Bonnell, John; Case, Anthony; de Wit, Thierry; Goetz, Keith; Harvey, Peter; Kasper, Justin; Korreck, Kelly; Livi, Roberto; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Stevens, Michael; YEAR: 2020 DOI: 10.3847/1538-4357/ab7b7a Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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In Situ Observations of Interplanetary Dust Variability in the Inner Heliosphere This work examines the variation of interplanetary dust count rates and directionality during the first three solar encounters made by the Parker Solar Probe spacecraft, covering distances between 0.65 au (\~140 solar radii, RS) and 0.16 au (\~35 RS). Dust detections are made by the FIELDS instrument via plasma clouds, produced by impact ionization of dust grains on spacecraft surfaces and resultant spacecraft potential perturbations. Dust count rates and inferred densities are found to vary by \~50\ ... Malaspina, David; Szalay, Jamey; y, Petr; Page, Brent; Bale, Stuart; Bonnell, John; de Wit, Thierry; Goetz, Keith; Goodrich, Katherine; Harvey, Peter; MacDowall, Robert; Pulupa, Marc; YEAR: 2020 DOI: 10.3847/1538-4357/ab799b |
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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.; 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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Observations by the Parker Solar Probe mission of the solar wind at \~35.7 solar radii reveal the existence of whistler wave packets with frequencies below 0.1 fce (20-80 Hz in the spacecraft frame). These waves often coincide with local minima of the magnetic field magnitude or with sudden deflections of the magnetic field that are called switchbacks. Their sunward propagation leads to a significant Doppler frequency downshift from 200-300 to 20-80 Hz (from 0.2 to 0.5 fce). The polarization of these ... Agapitov, O.; de Wit, Dudok; Mozer, F.; Bonnell, J.; Drake, J.; Malaspina, D.; Krasnoselskikh, V.; Bale, S.; Whittlesey, P.; Case, A.; Chaston, C.; Froment, C.; Goetz, K.; Goodrich, K.; Harvey, P.; Kasper, J.; Korreck, K.; Larson, D.; Livi, R.; MacDowall, R.; Pulupa, M.; Revillet, C.; Stevens, M.; Wygant, J.; YEAR: 2020 DOI: 10.3847/2041-8213/ab799c Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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In-situ Switchback Formation in the Expanding Solar Wind Recent near-Sun solar-wind observations from Parker Solar Probe have found a highly dynamic magnetic environment, permeated by abrupt radial-field reversals, or "switchbacks." We show that many features of the observed turbulence are reproduced by a spectrum of Alfv\ enic fluctuations advected by a radially expanding flow. Starting from simple superpositions of low-amplitude outward-propagating waves, our expanding-box compressible magnetohydrodynamic simulations naturally develop switchbacks because (i) the normalized am ... Squire, J.; Chandran, B.; Meyrand, R.; YEAR: 2020 DOI: 10.3847/2041-8213/ab74e1 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
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Sharp Alfv\ enic Impulses in the Near-Sun Solar Wind Measurements of the near-Sun solar wind by the Parker Solar Probe have revealed the presence of large numbers of discrete Alfv\ enic impulses with an anti-sunward sense of propagation. These are similar to those previously observed near 1 au, in high speed streams over the Sun\textquoterights poles and at 60 solar radii. At 35 solar radii, however, they are typically shorter and sharper than seen elsewhere. In addition, these spikes occur in "patches" and there are also clear periods within the same stream when they do no ... Horbury, Timothy; Woolley, Thomas; Laker, Ronan; Matteini, Lorenzo; Eastwood, Jonathan; Bale, Stuart; Velli, Marco; Chandran, Benjamin; Phan, Tai; Raouafi, Nour; Goetz, Keith; Harvey, Peter; Pulupa, Marc; Klein, K.; de Wit, Thierry; Kasper, Justin; Korreck, Kelly; Case, A.; Stevens, Michael; Whittlesey, Phyllis; Larson, Davin; MacDowall, Robert; Malaspina, David; Livi, Roberto; YEAR: 2020 DOI: 10.3847/1538-4365/ab5b15 |
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Small, Low-energy, Dispersive Solar Energetic Particle Events Observed by Parker Solar Probe The Energetic Particle Instrument-Low Energy (EPI-Lo) experiment has detected several weak, low-energy (̃30-300 keV nucleon-1) solar energetic particle (SEP) events during its first two closest approaches to the Sun, providing a unique opportunity to explore the sources of low-energy particle acceleration. As part of the Parker Solar Probe (PSP) Integrated Science Investigation of the Sun (IS☉IS) suite, EPI-Lo was designed to investigate the physics of energetic particles; however, in the special lowest-ener ... Hill, M.; Mitchell, D.; Allen, R.; de Nolfo, G.; Vourlidas, A.; Brown, L.; Jones, S.; McComas, D.; McNutt, R.; Mitchell, J.; Szalay, J.; Wallace, S.; Arge, C.; Christian, E.; Cohen, C.; Crew, A.; Desai, M.; Giacalone, J.; Henney, C.; Joyce, C.; Krimigis, S.; Leske, R.; Mewaldt, R.; Nelson, K.; Roelof, E.; Schwadron, N.; Wiedenbeck, M.; YEAR: 2020 DOI: 10.3847/1538-4365/ab643d |
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Solar Energetic Particles Produced by a Slow Coronal Mass Ejection at \~0.25 au We present an analysis of Parker Solar Probe (PSP) IS☉IS observations of ̃30-300 keV n-1 ions on 2018 November 11 when PSP was about 0.25 au from the Sun. Five hours before the onset of a solar energetic particle (SEP) event, a coronal mass ejection (CME) was observed by STEREO-A/COR2, which crossed PSP about a day later. No shock was observed locally at PSP, but the CME may have driven a weak shock earlier. The SEP event was dispersive, with higher energy ions arriving before the lower energy ones. Timing s ... Giacalone, J.; Mitchell, D.; Allen, R.; Hill, M.; McNutt, R.; Szalay, J.; Desai, M.; Rouillard, A.; Kouloumvakos, A.; McComas, D.; Christian, E.; Schwadron, N.; Wiedenbeck, M.; Bale, S.; Brown, L.; Case, A.; Chen, X.; Cohen, C.; Joyce, C.; Kasper, J.; Klein, K.; Korreck, K.; Larson, D.; Livi, R.; Leske, R.; MacDowall, R.; Matthaeus, W.; Mewaldt, R.; Nieves-Chinchilla, T.; Pulupa, M.; Roelof, E.; Stevens, M.; Szabo, A.; Whittlesey, P.; YEAR: 2020 DOI: 10.3847/1538-4365/ab5221 |
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The Solar Probe ANalyzers\textemdashElectrons on the Parker Solar Probe Electrostatic analyzers of different designs have been used since the earliest days of the space age, beginning with the very earliest solar-wind measurements made by Mariner 2 en route to Venus in 1962. The Parker Solar Probe (PSP) mission, NASA\textquoterights first dedicated mission to study the innermost reaches of the heliosphere, makes its thermal plasma measurements using a suite of instruments called the Solar Wind Electrons, Alphas, and Protons (SWEAP) investigation. SWEAP\textquoterights electron PSP Analyzer (S ... Whittlesey, Phyllis; Larson, Davin; Kasper, Justin; Halekas, Jasper; Abatcha, Mamuda; Abiad, Robert; Berthomier, M.; Case, A.; Chen, Jianxin; Curtis, David; Dalton, Gregory; Klein, Kristopher; Korreck, Kelly; Livi, Roberto; Ludlam, Michael; Marckwordt, Mario; Rahmati, Ali; Robinson, Miles; Slagle, Amanda; Stevens, M.; Tiu, Chris; Verniero, J.; YEAR: 2020 DOI: 10.3847/1538-4365/ab7370 Astrophysics - Instrumentation and Methods for Astrophysics; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar coronal heating; Solar instruments; Solar Probe Plus; Solar wind; Space plasmas |
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The Solar Probe Cup on the Parker Solar Probe Solar Probe Cup (SPC) is a Faraday cup instrument on board NASA\textquoterights Parker Solar Probe (PSP) spacecraft designed to make rapid measurements of thermal coronal and solar wind plasma. The spacecraft is in a heliocentric orbit that takes it closer to the Sun than any previous spacecraft, allowing measurements to be made where the coronal and solar wind plasma is being heated and accelerated. The SPC instrument was designed to be pointed directly at the Sun at all times, allowing the solar wind (which is flowing p ... Case, A.; Kasper, Justin; Stevens, Michael; Korreck, Kelly; Paulson, Kristoff; Daigneau, Peter; Caldwell, Dave; Freeman, Mark; Henry, Thayne; Klingensmith, Brianna; Bookbinder, J.; Robinson, Miles; Berg, Peter; Tiu, Chris; Wright, K.; Reinhart, Matthew; Curtis, David; Ludlam, Michael; Larson, Davin; Whittlesey, Phyllis; Livi, Roberto; Klein, Kristopher; c, Mihailo; YEAR: 2020 DOI: 10.3847/1538-4365/ab5a7b Astrophysics - Instrumentation and Methods for Astrophysics; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
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Several fast solar wind streams and stream interaction regions (SIRs) were observed by the Parker Solar Probe (PSP) during its first orbit (2018 September-2019 January). During this time, several recurring SIRs were also seen at 1 au at both L1 (Advanced Composition Explorer (ACE) and Wind) and the location of the Solar Terrestrial Relations Observatory-Ahead (STEREO-A). In this paper, we compare four fast streams observed by PSP at different radial distances during its first orbit. For three of these fast stream events, ... Allen, R.; Lario, D.; Odstrcil, D.; Ho, G.; Jian, L.; Cohen, C.; Badman, S.; Jones, S.; Arge, C.; Mays, M.; Mason, G.; Bale, S.; Bonnell, J.; Case, A.; Christian, E.; de Wit, Dudok; Goetz, K.; Harvey, P.; Henney, C.; Hill, M.; Kasper, J.; Korreck, K.; Larson, D.; Livi, R.; MacDowall, R.; Malaspina, D.; McComas, D.; McNutt, R.; Mitchell, D.; Pulupa, M.; Raouafi, N.; Schwadron, N.; Stevens, M.; Whittlesey, P.; Wiedenbeck, M.; YEAR: 2020 DOI: 10.3847/1538-4365/ab578f |
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In the first orbit of the Parker Solar Probe (PSP), in situ thermal plasma and magnetic field measurements were collected as close as 35 RSun from the Sun, an environment that had not been previously explored. During the first orbit of PSP, the spacecraft flew through a streamer blowout coronal mass ejection (SBO-CME) on 2018 November 11 at 23:50 UT as it exited the science encounter. The SBO-CME on November 11 was directed away from the Earth and was not visible by L1 or Earth-based telescopes due to this geom ... Korreck, Kelly; Szabo, Adam; Chinchilla, Teresa; Lavraud, Benoit; Luhmann, Janet; Niembro, Tatiana; Higginson, Aleida; Alzate, Nathalia; Wallace, Samantha; Paulson, Kristoff; Rouillard, Alexis; Kouloumvakos, Athanasios; Poirier, Nicolas; Kasper, Justin; Case, A.; Stevens, Michael; Bale, Stuart; Pulupa, Marc; Whittlesey, Phyllis; Livi, Roberto; Goetz, Keith; Larson, Davin; Malaspina, David; Morgan, Huw; Narock, Ayris; Schwadron, Nathan; Bonnell, John; Harvey, Peter; Wygant, John; YEAR: 2020 DOI: 10.3847/1538-4365/ab6ff9 |
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Statistics and Polarization of Type III Radio Bursts Observed in the Inner Heliosphere We present initial results from the Radio Frequency Spectrometer, the high-frequency component of the FIELDS experiment on the Parker Solar Probe (PSP). During the first PSP solar encounter (2018 November), only a few small radio bursts were observed. During the second encounter (2019 April), copious type III radio bursts occurred, including intervals of radio storms where bursts occurred continuously. In this paper, we present initial observations of the characteristics of type III radio bursts in the inner heliosphere, ... Pulupa, Marc; Bale, Stuart; Badman, Samuel; Bonnell, J.; Case, Anthony; de Wit, Thierry; Goetz, Keith; Harvey, Peter; Hegedus, Alexander; Kasper, Justin; Korreck, Kelly; Krasnoselskikh, Vladimir; Larson, Davin; Lecacheux, Alain; Livi, Roberto; MacDowall, Robert; Maksimovic, Milan; Malaspina, David; Oliveros, Juan; Meyer-Vernet, Nicole; Moncuquet, Michel; Stevens, Michael; Whittlesey, Phyllis; YEAR: 2020 DOI: 10.3847/1538-4365/ab5dc0 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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3 He-rich Solar Energetic Particle Observations at the Parker Solar Probe and near Earth The Integrated Science Investigation of the Sun (IS☉IS) instrument suite on the Parker Solar Probe (PSP) spacecraft is making in situ observations of energetic ions and electrons closer to the Sun than any previous mission. Using data collected during its first two orbits, which reached perihelion distances of 0.17 au, we have searched for \ 3\ He\ 3He -rich solar energetic particle (SEP) events under very quiet solar minimum conditions. On 2019-110-111 (April 20-21), \ 3\ He\ 3He -rich SEP ... Wiedenbeck, M.; ik, Bu\v; Mason, G.; Ho, G.; Leske, R.; Cohen, C.; Christian, E.; Cummings, A.; Davis, A.; Desai, M.; Giacalone, J.; Haggerty, D.; Hill, M.; Joyce, C.; Labrador, A.; Malandraki, O.; Matthaeus, W.; McComas, D.; McNutt, R.; Mewaldt, R.; Mitchell, D.; Posner, A.; Rankin, J.; Roelof, E.; Schwadron, N.; Stone, E.; Szalay, J.; Bale, S.; Case, A.; Kasper, J.; Korreck, K.; Larson, D.; MacDowall, R.; Pulupa, M.; Stevens, M.; YEAR: 2020 DOI: 10.3847/1538-4365/ab5963 |
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Switchbacks in the Near-Sun Magnetic Field: Long Memory and Impact on the Turbulence Cascade One of the most striking observations made by Parker Solar Probe during its first solar encounter is the omnipresence of rapid polarity reversals in a magnetic field that is otherwise mostly radial. These so-called switchbacks strongly affect the dynamics of the magnetic field. We concentrate here on their macroscopic properties. First, we find that these structures are self-similar, and have neither a characteristic magnitude, nor a characteristic duration. Their waiting time statistics show evidence of aggregation. The ... de Wit, Thierry; Krasnoselskikh, Vladimir; Bale, Stuart; Bonnell, John; Bowen, Trevor; Chen, Christopher; Froment, Clara; Goetz, Keith; Harvey, Peter; Jagarlamudi, Vamsee; Larosa, Andrea; MacDowall, Robert; Malaspina, David; Matthaeus, William; Pulupa, Marc; Velli, Marco; Whittlesey, Phyllis; YEAR: 2020 DOI: 10.3847/1538-4365/ab5853 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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Switchbacks (rotations of the magnetic field) are observed on the Parker Solar Probe. Their evolution, content, and plasma effects are studied in this paper. The solar wind does not receive a net acceleration from switchbacks that it encountered upstream of the observation point. The typical switchback rotation angle increased with radial distance. Significant Poynting fluxes existed inside, but not outside, switchbacks, and the dependence of the Poynting flux amplitude on the switchback radial location and rotation angle ... Mozer, F.; Agapitov, O.; Bale, S.; Bonnell, J.; Case, T.; Chaston, C.; Curtis, D.; de Wit, Dudok; Goetz, K.; Goodrich, K.; Harvey, P.; Kasper, J.; Korreck, K.; Krasnoselskikh, V.; Larson, D.; Livi, R.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Stevens, M.; Whittlesey, P.; Wygant, J.; YEAR: 2020 DOI: 10.3847/1538-4365/ab7196 |
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Time Domain Structures and Dust in the Solar Vicinity: Parker Solar Probe Observations On 2019 April 5, while the Parker Solar Probe was at its 35 solar radius perihelion, the data set collected at 293 samples/s contained more than 10,000 examples of spiky electric-field-like structures with durations less than 200 milliseconds and amplitudes greater than 10 mV m-1. The vast majority of these events were caused by plasma turbulence. Defining dust events as those with similar, narrowly peaked, positive, and single-ended signatures resulted in finding 135 clear dust events, which, after correcting ... Mozer, F.; Agapitov, O.; Bale, S.; Bonnell, J.; Goetz, K.; Goodrich, K.; Gore, R.; Harvey, P.; Kellogg, P.; Malaspina, D.; Pulupa, M.; Schumm, G.; YEAR: 2020 DOI: 10.3847/1538-4365/ab5e4b Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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Turbulence Transport Modeling and First Orbit Parker Solar Probe ( PSP ) Observations The Parker Solar Probe (PSP) achieved its first orbit perihelion on 2018 November 6, reaching a heliocentric distance of about 0.165 au (35.55 R☉). Here, we study the evolution of fully developed turbulence associated with the slow solar wind along the PSP trajectory between 35.55 R☉ and 131.64 R☉ in the outbound direction, comparing observations to a theoretical turbulence transport model. Several turbulent quantities, such as the fluctuating kinetic energy and the corresponding cor ... Adhikari, L.; Zank, G.; Zhao, L.-L.; Kasper, J.; Korreck, K.; Stevens, M.; Case, A.; Whittlesey, P.; Larson, D.; Livi, R.; Klein, K.; YEAR: 2020 DOI: 10.3847/1538-4365/ab5852 Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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WISPR Imaging of a Pristine CME The Wide-field Imager for Solar Probe (WISPR) on board the Parker Solar Probe (PSP) observed a coronal mass ejection (CME) on 2018 November 1, the first day of the initial PSP encounter. The speed of the CME, approximately 200-300 km s-1 in the WISPR field of view, is typical of slow, streamer blowout CMEs. This event was also observed by the Large Angle and Spectrometric Coronagraph Experiment (LASCO) coronagraphs. WISPR and LASCO view remarkably similar structures that enable useful cross-comparison between t ... Hess, Phillip; Rouillard, Alexis; Kouloumvakos, Athanasios; Liewer, Paulett; Zhang, Jie; Dhakal, Suman; Stenborg, Guillermo; Colaninno, Robin; Howard, Russell; YEAR: 2020 DOI: 10.3847/1538-4365/ab4ff0 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; YEAR: 2020 DOI: 10.3847/1538-4365/ab61f5 |
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We discuss the solar wind electron temperatures Te as measured in the nascent solar wind by Parker Solar Probe during its first perihelion pass. The measurements have been obtained by fitting the high-frequency part of quasi-thermal noise spectra recorded by the Radio Frequency Spectrometer. In addition we compare these measurements with those obtained by the electrostatic analyzer discussed in Halekas et al. These first electron observations show an anticorrelation between Te and the wind bulk speed ... Maksimovic, M.; Bale, S.; c, Ber\v; Bonnell, J.; Case, A.; de Wit, Dudok; Goetz, K.; Halekas, J.; Harvey, P.; Issautier, K.; Kasper, J.; Korreck, K.; Jagarlamudi, Krishna; Lahmiti, N.; Larson, D.; Lecacheux, A.; Livi, R.; MacDowall, R.; Malaspina, D.; c, M.; Meyer-Vernet, N.; Moncuquet, M.; Pulupa, M.; Salem, C.; Stevens, M.; ak, \v; Velli, M.; Whittlesey, P.; YEAR: 2020 DOI: 10.3847/1538-4365/ab61fc |
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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.; 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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Cross Helicity Reversals in Magnetic Switchbacks We consider 2D joint distributions of normalized residual energy, σr(s, t), and cross helicity, σc(s, t), during one day of Parker Solar Probe\textquoterights (PSP\textquoterights) first encounter as a function of wavelet scale s. The broad features of the distributions are similar to previous observations made by Helios in slow solar wind, namely well-correlated and fairly Alfv\ enic wind, except for a population with negative cross helicity that is seen at shorter wavelet scales. We show that thi ... McManus, Michael; Bowen, Trevor; Mallet, Alfred; Chen, Christopher; Chandran, Benjamin; Bale, Stuart; Larson, Davin; de Wit, Thierry; Kasper, J.; Stevens, Michael; Whittlesey, Phyllis; Livi, Roberto; Korreck, Kelly; Goetz, Keith; Harvey, Peter; Pulupa, Marc; MacDowall, Robert; Malaspina, David; Case, Anthony; Bonnell, J.; YEAR: 2020 DOI: 10.3847/1538-4365/ab6dce Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
