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Found 506 entries in the Bibliography.
Showing entries from 251 through 300
2020 |
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 ... Bercic, 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; Published by: The Astrophysical Journal Published on: 04/2020 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 |
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; Published by: The Astrophysical Journal Published on: 04/2020 YEAR: 2020   DOI: 10.3847/1538-4357/ab799b |
Electron Energy Partition across Interplanetary Shocks. III. Analysis Wilson, Lynn; Chen, Li-Jen; Wang, Shan; Schwartz, Steven; Turner, Drew; Stevens, Michael; Kasper, Justin; Osmane, Adnane; Caprioli, Damiano; Bale, Stuart; Pulupa, Marc; Salem, Chadi; Goodrich, Katherine; Published by: \apj Published on: 04/2020 YEAR: 2020   DOI: 10.3847/1538-4357/ab7d39 Parker Data Used; 1534; 829; 310; 1997; 1544; 1261; 2089; 826; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics |
One of the discoveries of the Parker Solar Probe during its first encounters with the Sun is ubiquitous presence of relatively small-scale structures standing out as sudden deflections of the magnetic field. They were named "switchbacks" since some of them show a full reversal of the radial component of the magnetic field and then return to "regular" conditions. We carried out an analysis of three typical switchback structures having different characteristics: I. Alfv\ enic structure, where the variations of the magnetic ... Krasnoselskikh, V.; Larosa, A.; Agapitov, O.; de Wit, Dudok; Moncuquet, M.; Mozer, F.; Stevens, M.; Bale, S.; Bonnell, J.; Froment, C.; Goetz, K.; Goodrich, K.; Harvey, P.; Kasper, J.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Raouafi, N.; Revillet, C.; Velli, M.; Wygant, J.; Published by: The Astrophysical Journal Published on: 04/2020 YEAR: 2020   DOI: 10.3847/1538-4357/ab7f2d Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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 ... Nisticò, Giuseppe; Bothmer, Volker; Vourlidas, Angelos; Liewer, Paulett; Thernisien, Arnaud; Stenborg, Guillermo; Howard, Russell; Published by: Solar Physics Published on: 04/2020 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 |
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 ... Published by: The Astrophysical Journal Published on: 04/2020 YEAR: 2020   DOI: 10.3847/1538-4357/ab7e32 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Solar Probe Plus |
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.; Published by: The Astrophysical Journal Published on: 03/2020 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 |
Pathways to Dissipation in Weakly Collisional Plasmas Matthaeus, William; Yang, Yan; Wan, Minping; Parashar, Tulasi; Bandyopadhyay, Riddhi; Chasapis, Alexandros; Pezzi, Oreste; Valentini, Francesco; Published by: \apj Published on: 03/2020 YEAR: 2020   DOI: 10.3847/1538-4357/ab6d6a |
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.; Published by: The Astrophysical Journal Published on: 03/2020 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 |
In this paper, we present an analysis of the internal structure of a coronal mass ejection (CME) detected by in situ instruments on board the Parker Solar Probe (PSP) spacecraft during its first solar encounter. On 2018 November 11 at 23:53 UT, the FIELDS magnetometer measured an increase in strength of the magnetic field as well as a coherent change in the field direction. The SWEAP instrument simultaneously detected a low proton temperature and signatures of bidirectionality in the electron pitch angle distribution (PAD ... Nieves-Chinchilla, Teresa; Szabo, Adam; Korreck, Kelly; Alzate, Nathalia; Balmaceda, Laura; Lavraud, Benoit; Paulson, Kristoff; Narock, Ayris; Wallace, Samantha; Jian, Lan; Luhmann, Janet; Morgan, Huw; Higginson, Aleida; Arge, Charles; Bale, Stuart; Case, Anthony; de Wit, Thierry; Giacalone, Joe; Goetz, Keith; Harvey, Peter; Jones-Melosky, Shaela; Kasper, J.; Larson, Davin; Livi, Roberto; McComas, David; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Raouafi, Nour; Schwadron, Nathan; Stevens, Michael; Whittlesey, Phyllis; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab61f5 |
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.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab61fc |
During the Parker Solar Probe\textquoterights (PSP) first perihelion pass, the spacecraft reached within a heliocentric distance of ̃37 R☉ and observed numerous magnetic and flow structures characterized by sharp gradients. To better understand these intermittent structures in the young solar wind, an important property to examine is their degree of correlation in time and space. To this end, we use the well-tested partial variance of increments (PVI) technique to identify intermittent events in FIELDS and S ... Chhiber, Rohit; Goldstein, M; Maruca, B.; Chasapis, A.; Matthaeus, W.; Ruffolo, D.; Bandyopadhyay, R.; Parashar, T.; Qudsi, R.; de Wit, Dudok; Bale, S.; Bonnell, J.; Goetz, K.; Harvey, P.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Kasper, J.; Korreck, K.; Case, A.; Stevens, M.; Whittlesey, P.; Larson, D.; Livi, R.; Velli, M.; Raouafi, N.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab53d2 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 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 |
Density Fluctuations in the Solar Wind Based on Type III Radio Bursts Observed by Parker Solar Probe Radio waves are strongly scattered in the solar wind, so that their apparent sources seem to be considerably larger and shifted than the actual ones. Since the scattering depends on the spectrum of density turbulence, a better understanding of the radio wave propagation provides indirect information on the relative density fluctuations, ϵ=⟨δn⟩/⟨n⟩\ ϵ=⟨δn⟩/⟨n⟩ , at the effective turbulence scale length. Here, we analyzed 30 type III bursts detected by Parker Sola ... Krupar, Vratislav; Szabo, Adam; Maksimovic, Milan; Kruparova, Oksana; Kontar, Eduard; Balmaceda, Laura; Bonnin, Xavier; Bale, Stuart; Pulupa, Marc; Malaspina, David; Bonnell, John; Harvey, Peter; Goetz, Keith; de Wit, Thierry; MacDowall, Robert; Kasper, Justin; Case, Anthony; Korreck, Kelly; Larson, Davin; Livi, Roberto; Stevens, Michael; Whittlesey, Phyllis; Hegedus, Alexander; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab65bd Astrophysics - Earth and Planetary Astrophysics; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
Detailed Imaging of Coronal Rays with the Parker Solar Probe The Wide-field Imager for Solar PRobe (WISPR) obtained the first high-resolution images of coronal rays at heights below 15 R☉ when the Parker Solar Probe (PSP) was located inside 0.25 au during the first encounter. We exploit these remarkable images to reveal the structure of coronal rays at scales that are not easily discernible in images taken from near 1 au. To analyze and interpret WISPR observations, which evolve rapidly both radially and longitudinally, we construct a latitude versus time map using the ... Poirier, Nicolas; Kouloumvakos, Athanasios; Rouillard, Alexis; Pinto, Rui; Vourlidas, Angelos; Stenborg, Guillermo; Valette, Emeline; Howard, Russell; Hess, Phillip; Thernisien, Arnaud; Rich, Nathan; Griton, Lea; Indurain, Mikel; Raouafi, Nour-Edine; Lavarra, Michael; Réville, Victor; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab6324 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
Electrons in the Young Solar Wind: First Results from the Parker Solar Probe The Solar Wind Electrons Alphas and Protons experiment on the Parker Solar Probe (PSP) mission measures the three-dimensional electron velocity distribution function. We derive the parameters of the core, halo, and strahl populations utilizing a combination of fitting to model distributions and numerical integration for ̃100,000 electron distributions measured near the Sun on the first two PSP orbits, which reached heliocentric distances as small as ̃0.17 au. As expected, the electron core density and temperature increa ... Halekas, J.; Whittlesey, P.; Larson, D.; McGinnis, D.; Maksimovic, M.; Berthomier, M.; Kasper, J.; Case, A.; Korreck, K.; Stevens, M.; Klein, K.; Bale, S.; MacDowall, R.; Pulupa, M.; Malaspina, D.; Goetz, K.; Harvey, P.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab4cec Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
Operational Modeling of Heliospheric Space Weather for the Parker Solar Probe The interpretation of multi-spacecraft heliospheric observations and three-dimensional reconstruction of the structured and evolving solar wind with propagating and interacting coronal mass ejections (CMEs) is a challenging task. Numerical simulations can provide global context and suggest what may and may not be observed. The Community Coordinated Modeling Center (CCMC) provides both mission science and space weather support to all heliospheric missions. Currently, this is realized by real-time simulations of the corotating ... Odstrcil, Dusan; Mays, Leila; Hess, Phillip; Jones, Shaela; Henney, Carl; Arge, Charles; Published by: ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab77cb |
Energetic Particle Increases Associated with Stream Interaction Regions The Parker Solar Probe was launched on 2018 August 12 and completed its second orbit on 2019 June 19 with perihelion of 35.7 solar radii. During this time, the Energetic Particle Instrument-Hi (EPI-Hi, one of the two energetic particle instruments comprising the Integrated Science Investigation of the Sun, IS☉IS) measured seven proton intensity increases associated with stream interaction regions (SIRs), two of which appear to be occurring in the same region corotating with the Sun. The events are relatively weak, with ... Cohen, C.; Christian, E.; Cummings, A.; Davis, A.; Desai, M.; Giacalone, J.; Hill, M.; Joyce, C.; Labrador, A.; Leske, R.; Matthaeus, W.; McComas, D.; McNutt, R.; Mewaldt, R.; Mitchell, D.; Rankin, J.; Roelof, E.; Schwadron, N.; Stone, E.; Szalay, J.; Wiedenbeck, M.; Allen, R.; Ho, G.; Jian, L.; Lario, D.; Odstrcil, D.; Bale, S.; Badman, S.; Pulupa, M.; MacDowall, R.; Kasper, J.; Case, A.; Korreck, K.; Larson, D.; Livi, Roberto; Stevens, M.; Whittlesey, Phyllis; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab4c38 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
The Integrated Science Investigations of the Sun (IS☉IS) instrument suite includes two Energetic Particle instruments: EPI-Hi, designed to measure ions from ̃1 to 200 MeV nuc-1, and EPI-Lo, designed to measure ions from ̃20 to ̃15 MeV nuc-1. We present an analysis of eight energetic proton events observed across the energy range of both instruments during Parker Solar Probe\textquoterights (PSP) first two orbits in order to examine their combined energy spectra. Background corrections are applie ... Joyce, C.; McComas, D.; Christian, E.; Schwadron, N.; Wiedenbeck, M.; McNutt, R.; Cohen, C.; Leske, R.; Mewaldt, R.; Stone, E.; Labrador, A.; Davis, A.; Cummings, A.; Mitchell, D.; Hill, M.; Roelof, E.; Szalay, J.; Rankin, J.; Desai, M.; Giacalone, J.; Matthaeus, W.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab5948 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
Enhanced Energy Transfer Rate in Solar Wind Turbulence Observed near the Sun from Parker Solar Probe Direct evidence of an inertial-range turbulent energy cascade has been provided by spacecraft observations in heliospheric plasmas. In the solar wind, the average value of the derived heating rate near 1 au is \~10\ 3\ Jkg\ -1\ s\ -1\ \ \~103Jkg-1s-1 , an amount sufficient to account for observed departures from adiabatic expansion. Parker Solar Probe, even during its first solar encounter, offers the first opportunity to compute, in a similar fashion, a fluid-scale energy decay rate, mu ... Bandyopadhyay, Riddhi; Goldstein, M.; Maruca, B.; Matthaeus, W.; Parashar, T.; Ruffolo, D.; Chhiber, R.; Usmanov, A.; Chasapis, A.; Qudsi, R.; Bale, Stuart; Bonnell, J.; de Wit, Thierry; Goetz, Keith; Harvey, Peter; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Kasper, J.; Korreck, K.; Case, A.; Stevens, M.; Whittlesey, P.; Larson, D.; Livi, R.; Klein, K.; Velli, M.; Raouafi, N.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab5dae Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
The Enhancement of Proton Stochastic Heating in the Near-Sun Solar Wind Stochastic heating (SH) is a nonlinear heating mechanism driven by the violation of magnetic moment invariance due to large-amplitude turbulent fluctuations producing diffusion of ions toward higher kinetic energies in the direction perpendicular to the magnetic field. It is frequently invoked as a mechanism responsible for the heating of ions in the solar wind. Here, we quantify for the first time the proton SH rate Q⊥ at radial distances from the Sun as close as 0.16 au, using measurements from the first tw ... Martinovic, Mihailo; Klein, Kristopher; Kasper, Justin; Case, Anthony; Korreck, Kelly; Larson, Davin; Livi, Roberto; Stevens, Michael; Whittlesey, Phyllis; Chandran, Benjamin; Alterman, Ben; Huang, Jia; Chen, Christopher; Bale, Stuart; Pulupa, Marc; Malaspina, David; Bonnell, John; Harvey, Peter; Goetz, Keith; de Wit, Thierry; MacDowall, Robert; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab527f Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Solar Probe Plus |
The Evolution and Role of Solar Wind Turbulence in the Inner Heliosphere The first two orbits of the Parker Solar Probe spacecraft have enabled the first in situ measurements of the solar wind down to a heliocentric distance of 0.17 au (or 36 R\ ⊙\ \ R⊙ ). Here, we present an analysis of this data to study solar wind turbulence at 0.17 au and its evolution out to 1 au. While many features remain similar, key differences at 0.17 au include increased turbulence energy levels by more than an order of magnitude, a magnetic field spectral index of -3/2 matching that of t ... Chen, C.; Bale, S.; Bonnell, J.; Borovikov, D.; Bowen, T.; Burgess, D.; Case, A.; Chandran, B.; de Wit, Dudok; Goetz, K.; Harvey, P.; Kasper, J.; Klein, K.; Korreck, K.; Larson, D.; Livi, R.; MacDowall, R.; Malaspina, D.; Mallet, A.; McManus, M.; Moncuquet, M.; Pulupa, M.; Stevens, M.; Whittlesey, P.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab60a3 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
Examining Dust Directionality with the Parker Solar Probe FIELDS Instrument Parker Solar Probe\textquoterights (PSP\textquoterights) FIELDS instrument provides a measure of the dust impact rate on the spacecraft with a full-coverage summary of the voltages recorded by the spacecraft\textquoterights antennas. From consecutively sampled periods throughout PSP\textquoterights orbit, FIELDS stores the maximum amplitude measured by each active antenna. The occurrence of a dust impact during a given period can be identified by these amplitudes exceeding a few tens of millivolts, and a dust grain\textqu ... Page, Brent; Bale, Stuart; Bonnell, J.; Goetz, Keith; Goodrich, Katherine; Harvey, Peter; Larsen, Rhiannon; MacDowall, Robert; Malaspina, David; y, Petr; Pulupa, Marc; Szalay, Jamey; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab5f6a |
MHD Mode Composition in the Inner Heliosphere from the Parker Solar Probe s First Perihelion Field and plasma variations during the first perihelion pass of the Parker Solar Probe (PSP) from 53 into 35 solar radii (R-S) from the Sun and over a frequency range in the spacecraft frame (f(SC)) from 0.0002 to 0.2 Hz are decomposed into constituent magnetohydrodynamic (MHD) modes. The analysis operates on measurements of the MHD variables recorded between impulsive, large amplitude rotations of the magnetic field to reveal the dominance of a broad spectrum of shear Alfven waves propagating antiparallel (backward) to the ... Chaston, C.; Bonnell, J.; Bale, S.; Kasper, J.; Pulupa, M.; de Wit, Dudok; Bowen, T.; Larson, D.; Whittlesey, P.; Wygant, J.; Salem, C.; MacDowall, R.; Livi, R.; Vech, D.; Case, A.; Stevens, M.; Korreck, K.; Goetz, K.; Harvey, P.; Malaspina, D.; Published by: ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab745c |
The magnetic field measurements of the FIELDS instrument on the Parker Solar Probe (PSP) have shown intensities, throughout its first solar encounter, that require a very low source surface (SS) height ( R\ SS\ ⩽1.8R\ ⊙\ \ RSS⩽1.8R⊙ ) to be reconciled with magnetic field measurements at the Sun via potential field extrapolation (PFSS). However, during PSP\textquoterights second encounter, the situation went back to a more classic SS height ( R\ SS\ ⩽2 ... Panasenco, Olga; Velli, Marco; D\textquoterightAmicis, Raffaella; Shi, Chen; Réville, Victor; Bale, Stuart; Badman, Samuel; Kasper, Justin; Korreck, Kelly; Bonnell, J.; de Wit, Thierry; Goetz, Keith; Harvey, Peter; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Case, Anthony; Larson, Davin; Livi, Roberto; Stevens, Michael; Whittlesey, Phyllis; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab61f4 |
Heat transport in the solar corona and wind is still a major unsolved astrophysical problem. Because of the key role played by electrons, the electron density and temperature(s) are important prerequisites for understanding these plasmas. We present such in situ measurements along the two first solar encounters of the Parker Solar Probe, between 0.5 and 0.17 au from the Sun, revealing different states of the emerging solar wind near the solar activity minimum. These preliminary results are obtained from a simplified analy ... Moncuquet, Michel; Meyer-Vernet, Nicole; Issautier, Karine; Pulupa, Marc; Bonnell, J.; Bale, Stuart; de Wit, Thierry; Goetz, Keith; Griton, Lea; Harvey, Peter; MacDowall, Robert; Maksimovic, Milan; Malaspina, David; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab5a84 Astrophysics - Instrumentation and Methods for Astrophysics; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
The Heliospheric Current Sheet in the Inner Heliosphere Observed by the Parker Solar Probe The Parker Solar Probe (PSP) completed its first solar encounter in 2018 November, bringing it closer to the Sun than any previous mission. This allowed in situ investigation of the heliospheric current sheet (HCS) inside the orbit of Venus. The Parker observations reveal a well defined magnetic sector structure placing the spacecraft in a negative polarity region for most of the encounter. The observed current sheet crossings are compared to the predictions of both potential field source surface and magnetohydrodynamic m ... Szabo, Adam; Larson, Davin; Whittlesey, Phyllis; Stevens, Michael; Lavraud, Benoit; Phan, Tai; Wallace, Samantha; Jones-Mecholsky, Shaela; Arge, Charles; Badman, Samuel; Odstrcil, Dusan; Pogorelov, Nikolai; Kim, Tae; Riley, Pete; Henney, Carl; Bale, Stuart; Bonnell, John; Case, Antony; de Wit, Thierry; Goetz, Keith; Harvey, Peter; Kasper, Justin; Korreck, Kelly; Koval, Andriy; Livi, Roberto; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab5dac |
The Parker Solar Probe (PSP) observed an interplanetary coronal mass ejection (ICME) event during its first orbit around the Sun, among many other events. This event is analyzed by applying a wavelet analysis technique to obtain the reduced magnetic helicity, cross helicity, and residual energy, the first two of which are magnetohydrodynamics (MHD) invariants. Our results show that the ICME, as a large-scale magnetic flux rope, possesses high magnetic helicity, very low cross helicity, and highly negative residual energy, ... Zhao, L.-L.; Zank, G.; Adhikari, L.; Hu, Q.; Kasper, J.; Bale, S.; Korreck, K.; Case, A.; Stevens, M.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Harvey, P.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Larson, D.; Livi, R.; Whittlesey, P.; Klein, K.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab4ff1 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
Ion-scale Electromagnetic Waves in the Inner Heliosphere Understanding the physical processes in the solar wind and corona that actively contribute to heating, acceleration, and dissipation is a primary objective of NASA\textquoterights Parker Solar Probe (PSP) mission. Observations of circularly polarized electromagnetic waves at ion scales suggest that cyclotron resonance and wave-particle interactions are dynamically relevant in the inner heliosphere. A wavelet-based statistical study of circularly polarized events in the first perihelion encounter of PSP demonstrates that t ... Bowen, Trevor; Mallet, Alfred; Huang, Jia; Klein, Kristopher; Malaspina, David; Stevens, Michael; Bale, Stuart; Bonnell, J.; Case, Anthony; Chandran, Benjamin; Chaston, C.; Chen, Christopher; de Wit, Thierry; Goetz, Keith; Harvey, Peter; Howes, Gregory; Kasper, J.; Korreck, Kelly; Larson, Davin; Livi, Roberto; MacDowall, Robert; McManus, Michael; Pulupa, Marc; Verniero, J.; Whittlesey, Phyllis; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab6c65 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
Parker Solar Probe In Situ Observations of Magnetic Reconnection Exhausts during Encounter 1 Magnetic reconnection in current sheets converts magnetic energy into particle energy. The process may play an important role in the acceleration and heating of the solar wind close to the Sun. Observations from Parker Solar Probe (PSP) provide a new opportunity to study this problem, as it measures the solar wind at unprecedented close distances to the Sun. During the first orbit, PSP encountered a large number of current sheets in the solar wind through perihelion at 35.7 solar radii. We performed a comprehensive survey ... Phan, T.; Bale, S.; Eastwood, J.; Lavraud, B.; Drake, J.; Oieroset, M.; Shay, M.; Pulupa, M.; Stevens, M.; MacDowall, R.; Case, A.; Larson, D.; Kasper, J.; Whittlesey, P.; Szabo, A.; Korreck, K.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Harvey, P.; Horbury, T.; Livi, R.; Malaspina, D.; Paulson, K.; Raouafi, N.; Velli, M.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab55ee Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
Parker Solar Probe Observations of a Dust Trail in the Orbit of (3200) Phaethon We present the identification and preliminary analysis of a dust trail following the orbit of (3200) Phaethon as seen in white-light images recorded by the Wide-field Imager for Parker Solar Probe (WISPR) instrument on the NASA Parker Solar Probe (PSP) mission. During PSP\textquoterights first solar encounter in 2018 November, a dust trail following Phaethon\textquoterights orbit was visible for several days and crossing two fields of view. Preliminary analyses indicate this trail to have a visual magnitude of 15.8 \textp ... Battams, Karl; Knight, Matthew; Kelley, Michael; Gallagher, Brendan; Howard, Russell; Stenborg, Guillermo; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab6c68 Astrophysics - Earth and Planetary Astrophysics; Parker Data Used; parker solar probe; Solar Probe Plus |
Mitchell, D.~G.; Giacalone, J.; Allen, R.~C.; Hill, M.~E.; McNutt, R.~L.; McComas, D.~J.; Szalay, J.~R.; Schwadron, N.~A.; Rouillard, A.~P.; Bale, S.~B.; Chaston, C.~C.; Pulupa, M.~P.; Whittlesey, P.~L.; Kasper, J.~C.; MacDowall, R.~J.; Christian, E.~R.; Wiedenbeck, M.~E.; Matthaeus, W.~H.; Published by: \apjs Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab63cc Parker Data Used; 1491; 310; 1496; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics |
Kinetic-scale Spectral Features of Cross Helicity and Residual Energy in the Inner Heliosphere In this work, we present the first results from the flux angle (FA) operation mode of the Faraday Cup instrument on board the Parker Solar Probe (PSP). The FA mode allows rapid measurements of phase space density fluctuations close to the peak of the proton velocity distribution function with a cadence of 293 Hz. This approach provides an invaluable tool for understanding kinetic-scale turbulence in the solar wind and solar corona. We describe a technique to convert the phase space density fluctuations into vector velocit ... Vech, Daniel; Kasper, Justin; Klein, Kristopher; Huang, Jia; Stevens, Michael; Chen, Christopher; Case, Anthony; Korreck, Kelly; Bale, Stuart; Bowen, Trevor; Whittlesey, Phyllis; Livi, Roberto; Larson, Davin; Malaspina, David; Pulupa, Marc; Bonnell, John; Harvey, Peter; Goetz, Keith; de Wit, Thierry; MacDowall, Robert; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab60a2 Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
We compare magnetic field measurements taken by the FIELDS instrument on board Parker Solar Probe (PSP) during its first solar encounter to predictions obtained by potential field source surface (PFSS) modeling. Ballistic propagation is used to connect the spacecraft to the source surface. Despite the simplicity of the model, our results show striking agreement with PSP\textquoterights first observations of the heliospheric magnetic field from ̃0.5 au (107.5 R☉) down to 0.16 au (35.7 R☉). Furthe ... Badman, Samuel; Bale, Stuart; Oliveros, Juan; Panasenco, Olga; Velli, Marco; Stansby, David; Buitrago-Casas, Juan; eville, Victor; Bonnell, John; Case, Anthony; de Wit, Thierry; Goetz, Keith; Harvey, Peter; Kasper, Justin; Korreck, Kelly; Larson, Davin; Livi, Roberto; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Stevens, Michael; Whittlesey, Phyllis; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab4da7 |
Magnetic Field Kinks and Folds in the Solar Wind Parker Solar Probe (PSP) observations during its first encounter at 35.7 R☉ have shown the presence of magnetic field lines that are strongly perturbed to the point that they produce local inversions of the radial magnetic field, known as switchbacks. Their counterparts in the solar wind velocity field are local enhancements in the radial speed, or jets, displaying (in all components) the velocity-magnetic field correlation typical of large amplitude Alfv\ en waves propagating away from the Sun. Switchbacks a ... Tenerani, Anna; Velli, Marco; Matteini, Lorenzo; eville, Victor; Shi, Chen; Bale, Stuart; Kasper, Justin; Bonnell, John; Case, Anthony; de Wit, Thierry; Goetz, Keith; Harvey, Peter; Klein, Kristopher; Korreck, Kelly; Larson, Davin; Livi, Roberto; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Stevens, Michael; Whittlesey, Phyllis; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab53e1 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
Measures of Scale-dependent Alfv\ enicity in the First PSP Solar Encounter The solar wind shows periods of highly Alfv\ enic activity, where velocity fluctuations and magnetic fluctuations are aligned or antialigned with each other. It is generally agreed that solar wind plasma velocity and magnetic field fluctuations observed by the Parker Solar Probe (PSP) during the first encounter are mostly highly Alfv\ enic. However, quantitative measures of Alfv\ enicity are needed to understand how the characterization of these fluctuations compares with standard measures from prior missions in the inner ... Parashar, T.; Goldstein, M.; Maruca, B.; Matthaeus, W.; Ruffolo, D.; Bandyopadhyay, R.; Chhiber, R.; Chasapis, A.; Qudsi, R.; Vech, D.; Roberts, D.; Bale, S.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Harvey, P.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Kasper, J.; Korreck, K.; Case, A.; Stevens, M.; Whittlesey, P.; Larson, D.; Livi, R.; Velli, M.; Raouafi, N.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab64e6 |
Morphological Reconstruction of a Small Transient Observed by Parker Solar Probe on 2018 November 5 On 2018 November 5, about 24 hr before the first close perihelion passage of Parker Solar Probe (PSP), a coronal mass ejection (CME) entered the field of view of the inner detector of the Wide-field Imager for Solar PRobe (WISPR) instrument on board PSP, with the northward component of its trajectory carrying the leading edge of the CME off the top edge of the detector about four hours after its first appearance. We connect this event to a very small jetlike transient observed from 1 au by coronagraphs on both the SOlar a ... Wood, Brian; Hess, Phillip; Howard, Russell; Stenborg, Guillermo; Wang, Yi-Ming; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab5219 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
The Near-Sun Dust Environment: Initial Observations from Parker Solar Probe The Parker Solar Probe (PSP) spacecraft has flown into the densest, previously unexplored, innermost region of our solar system\textquoterights zodiacal cloud. While PSP does not have a dedicated dust detector, multiple instruments on the spacecraft are sensitive to the effects of meteoroid bombardment. Here, we discuss measurements taken during PSP\textquoterights second orbit and compare them to models of the zodiacal cloud\textquoterights dust distribution. Comparing the radial impact rate trends and the timing and loc ... Szalay, J.; y, Pokorn\; Bale, S.; Christian, E.; Goetz, K.; Goodrich, K.; Hill, M.; Kuchner, M.; Larsen, R.; Malaspina, D.; McComas, D.; Mitchell, D.; Page, B.; Schwadron, N.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab50c1 Astrophysics - Earth and Planetary Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
Observations at 1 au have confirmed that enhancements in measured energetic-particle (EP) fluxes are statistically associated with "rough" magnetic fields, i.e., fields with atypically large spatial derivatives or increments, as measured by the Partial Variance of Increments (PVI) method. One way to interpret this observation is as an association of the EPs with trapping or channeling within magnetic flux tubes, possibly near their boundaries. However, it remains unclear whether this association is a transport or local ef ... Bandyopadhyay, Riddhi; Matthaeus, W.; Parashar, T.; Chhiber, R.; Ruffolo, D.; Goldstein, M.; Maruca, B.; Chasapis, A.; Qudsi, R.; McComas, D.; Christian, E.; Szalay, J.; Joyce, C.; Giacalone, J.; Schwadron, N.; Mitchell, D.; Hill, M.; Wiedenbeck, M.; McNutt, R.; Desai, M.; Bale, Stuart; Bonnell, J.; de Wit, Thierry; Goetz, Keith; Harvey, Peter; MacDowall, Robert; Malaspina, David; Pulupa, Marc; Velli, M.; Kasper, J.; Korreck, K.; Stevens, M.; Case, A.; Raouafi, N.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab6220 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
Observations of Heating along Intermittent Structures in the Inner Heliosphere from PSP Data The solar wind proton temperature at 1 au has been found to be correlated with small-scale intermittent magnetic structures, i.e., regions with enhanced temperature are associated with coherent structures, such as current sheets. Using Parker Solar Probe data from the first encounter, we study this association using measurements of the radial proton temperature, employing the partial variance of increments (PVI) technique to identify intermittent magnetic structures. We observe that the probability density functions of hi ... Qudsi, R.; Maruca, B.; Matthaeus, W.; Parashar, T.; Bandyopadhyay, Riddhi; Chhiber, R.; Chasapis, A.; Goldstein, Melvyn; Bale, S.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Harvey, P.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Kasper, J.; Korreck, K.; Case, A.; Stevens, M.; Whittlesey, P.; Larson, D.; Livi, R.; Velli, M.; Raouafi, N.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab5c19 Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
Observations of the 2019 April 4 Solar Energetic Particle Event at the Parker Solar Probe A solar energetic particle event was detected by the Integrated Science Investigation of the Sun (IS☉IS) instrument suite on Parker Solar Probe (PSP) on 2019 April 4 when the spacecraft was inside of 0.17 au and less than 1 day before its second perihelion, providing an opportunity to study solar particle acceleration and transport unprecedentedly close to the source. The event was very small, with peak 1 MeV proton intensities of ̃0.3 particles (cm2 sr s MeV)-1, and was undetectable above backgro ... Leske, R.; Christian, E.; Cohen, C.; Cummings, A.; Davis, A.; Desai, M.; Giacalone, J.; Hill, M.; Joyce, C.; Krimigis, S.; 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.; Wiedenbeck, M.; Vourlidas, A.; Bale, S.; MacDowall, R.; Pulupa, M.; Kasper, J.; Allen, R.; Case, A.; Korreck, K.; Livi, R.; Stevens, M.; Whittlesey, P.; Poduval, B.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab5712 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
Plasma Waves near the Electron Cyclotron Frequency in the Near-Sun Solar Wind Data from the first two orbits of the Sun by Parker Solar Probe reveal that the solar wind sunward of 50 solar radii is replete with plasma waves and instabilities. One of the most prominent plasma wave power enhancements in this region appears near the electron cyclotron frequency (fce). Most of this wave power is concentrated in electric field fluctuations near 0.7 fce and fce, with strong harmonics of both frequencies extending above fce. At least two distinct, often concurre ... Malaspina, David; Halekas, Jasper; c, Laura; Larson, Davin; Whittlesey, Phyllis; Bale, Stuart; Bonnell, John; de Wit, Thierry; Ergun, Robert; Howes, Gregory; Goetz, Keith; Goodrich, Katherine; Harvey, Peter; MacDowall, Robert; Pulupa, Marc; Case, Anthony; Kasper, Justin; Korreck, Kelly; Livi, Roberto; Stevens, Michael; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab4c3b Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
Predicting the Solar Wind at the Parker Solar Probe Using an Empirically Driven MHD Model Since its launch on 2018 August 12, Parker Solar Probe (PSP) has completed its first and second orbits around the Sun, having reached down to 35.7 solar radii at each perihelion. In anticipation of the exciting new data at such unprecedented distances, we have simulated the global 3D heliosphere using an MHD model coupled with a semi-empirical coronal model using the best available photospheric magnetograms as input. We compare our heliospheric MHD simulation results with in situ measurements along the PSP trajectory from ... Kim, T.; Pogorelov, N.; Arge, C.; Henney, C.; Jones-Mecholsky, S.; Smith, W.; Bale, S.; Bonnell, J.; de Wit, Dudok; Goetz, K.; Harvey, P.; MacDowall, R.; Malaspina, D.; Pulupa, M.; Kasper, J.; Korreck, K.; Stevens, M.; Case, A.; Whittlesey, P.; Livi, R.; Larson, D.; Klein, K.; Zank, G.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab58c9 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
The Integrated Science Investigation of the Sun (IS☉IS) suite on board NASA\textquoterights Parker Solar Probe (PSP) observed six distinct enhancements in the intensities of suprathermal-through-energetic (\~0.03-3 MeV nucleon-1) He ions associated with corotating or stream interaction regions (CIR or SIR) during its first two orbits. Our results from a survey of the time histories of the He intensities, spectral slopes, and anisotropies and the event-averaged energy spectra during these events show the follo ... Desai, M.; Mitchell, D.; Szalay, J.; Roelof, E.; Giacalone, J.; Hill, M.; McComas, D.; Christian, E.; Schwadron, N.; McNutt, R.; Wiedenbeck, M.; Joyce, C.; Cohen, C.; Ebert, R.; Dayeh, M.; Allen, R.; Davis, A.; Krimigis, S.; Leske, R.; Matthaeus, W.; Malandraki, O.; Mewaldt, R.; Labrador, A.; Stone, E.; Bale, S.; Pulupa, M.; MacDowall, R.; Kasper, J.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab65ef |
Magnetic field fluctuations in the solar wind are commonly observed to follow a power-law spectrum. Near proton-kinetic scales, a spectral break occurs that is commonly interpreted as a transition to kinetic turbulence. However, this transition is not yet entirely understood. By studying the scaling of the break with various plasma properties, it may be possible to constrain the processes leading to the onset of kinetic turbulence. Using data from the Parker Solar Probe, we measure the proton-scale break over a range of h ... Duan, Die; Bowen, Trevor; Chen, Christopher; Mallet, Alfred; He, Jiansen; Bale, Stuart; Vech, Daniel; Kasper, J.; Pulupa, Marc; Bonnell, John; Case, Anthony; de Wit, Thierry; Goetz, Keith; Harvey, Peter; Korreck, Kelly; Larson, Davin; Livi, Roberto; MacDowall, Robert; Malaspina, David; Stevens, Michael; Whittlesey, Phyllis; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab672d Parker Data Used; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Solar Probe Plus |
Relating Streamer Flows to Density and Magnetic Structures at the Parker Solar Probe The physical mechanisms that produce the slow solar wind are still highly debated. Parker Solar Probe\textquoterights (PSP\textquoterights) second solar encounter provided a new opportunity to relate in situ measurements of the nascent slow solar wind with white-light images of streamer flows. We exploit data taken by the Solar and Heliospheric Observatory, the Solar TErrestrial RElations Observatory (STEREO), and the Wide Imager on Solar Probe to reveal for the first time a close link between imaged streamer flows and th ... Rouillard, Alexis; Kouloumvakos, Athanasios; Vourlidas, Angelos; Kasper, Justin; Bale, Stuart; Raouafi, Nour-Edine; Lavraud, Benoit; Howard, Russell; Stenborg, Guillermo; Stevens, Michael; Poirier, Nicolas; Davies, Jackie; Hess, Phillip; Higginson, Aleida; Lavarra, Michael; Viall, Nicholeen; Korreck, Kelly; Pinto, Rui; Griton, Lea; eville, Victor; Louarn, Philippe; Wu, Yihong; Dalmasse, K\; enot, Vincent; Case, Anthony; Whittlesey, Phyllis; Larson, Davin; Halekas, Jasper; Livi, Roberto; Goetz, Keith; Harvey, Peter; MacDowall, Robert; Malaspina, D.; Pulupa, M.; Bonnell, J.; de Witt, Dudok; Penou, Emmanuel; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab579a Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Solar Probe Plus |
During Parker Solar Probe\textquoterights first orbit, the solar wind plasma was observed in situ closer than ever before, the perihelion on 2018 November 6 revealing a flow that is constantly permeated by large-amplitude Alfv\ enic fluctuations. These include radial magnetic field reversals, or switchbacks, that seem to be a persistent feature of the young solar wind. The measurements also reveal a very strong, unexpected, azimuthal velocity component. In this work, we numerically model the solar corona during this first ... Réville, Victor; Velli, Marco; Panasenco, Olga; Tenerani, Anna; Shi, Chen; Badman, Samuel; Bale, Stuart; Kasper, J.; Stevens, Michael; Korreck, Kelly; Bonnell, J.; Case, Anthony; de Wit, Thierry; Goetz, Keith; Harvey, Peter; Larson, Davin; Livi, Roberto; Malaspina, David; MacDowall, Robert; Pulupa, Marc; Whittlesey, Phyllis; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab4fef Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
Seed Population Preconditioning and Acceleration Observed by the Parker Solar Probe A series of solar energetic particle (SEP) events was observed by the Integrated Science Investigation of the Sun (IS☉IS) on the Parker Solar Probe (PSP) during the period from 2019 April 18 through 24. The PSP spacecraft was located near 0.48 au from the Sun on Parker spiral field lines that projected out to 1 au within ̃25\textdegree of the near-Earth spacecraft. These SEP events, though small compared to historically large SEP events, were among the largest observed thus far in the PSP mission and provide critical i ... Schwadron, N.; Bale, S.; Bonnell, J.; Case, A.; Christian, E.; Cohen, C.; Cummings, A.; Davis, A.; de Wit, Dudok; de Wet, W.; Desai, M.; Joyce, C.; Goetz, K.; Giacalone, J.; Gorby, M.; Harvey, P.; Heber, B.; Hill, M.; Karavolos, M.; Kasper, J.; Korreck, K.; Larson, D.; Livi, R.; Leske, R.; Malandraki, O.; MacDowall, R.; Malaspina, D.; Matthaeus, W.; McComas, D.; McNutt, R.; Mewaldt, R.; Mitchell, D.; Mays, L.; Niehof, J.; Odstrcil, D.; Pulupa, M.; Poduval, B.; Rankin, J.; Roelof, E.; Stevens, M.; Stone, E.; Szalay, J.; Wiedenbeck, M.; Winslow, R.; Whittlesey, P.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab5527 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab5b15 |
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.; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020   DOI: 10.3847/1538-4365/ab643d |