Found 13 entries in the Bibliography.
Showing entries from 1 through 13
2020 |
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 |
Tearing Instability and Periodic Density Perturbations in the Slow Solar Wind In contrast with the fast solar wind, which originates in coronal holes, the source of the slow solar wind is still debated. Often intermittent and enriched with low first ionization potential elements\textemdashakin to what is observed in closed coronal loops\textemdashthe slow wind could form in bursty events nearby helmet streamers. Slow winds also exhibit density perturbations that have been shown to be periodic and could be associated with flux ropes ejected from the tip of helmet streamers, as shown recently by the ... eville, Victor; Velli, Marco; Rouillard, Alexis; Lavraud, Benoit; Tenerani, Anna; Shi, Chen; Strugarek, Antoine; YEAR: 2020   DOI: 10.3847/2041-8213/ab911d Astrophysics - Solar and Stellar Astrophysics; Magnetohydrodynamics; parker solar probe; Physics - Plasma Physics; Physics - Space Physics; Plasma astrophysics; Slow solar wind; Solar magnetic reconnection; Solar Probe Plus; Solar wind |
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 |
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 |
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 |
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 |
Detailed Imaging of Coronal Rays with the Parker Solar Probe The Wide-field Imager for Solar PRobe (WISPR) obtained the first high-resolution images of coronal rays at heights below 15 R☉ when the Parker Solar Probe (PSP) was located inside 0.25 au during the first encounter. We exploit these remarkable images to reveal the structure of coronal rays at scales that are not easily discernible in images taken from near 1 au. To analyze and interpret WISPR observations, which evolve rapidly both radially and longitudinally, we construct a latitude versus time map using the ... Poirier, Nicolas; Kouloumvakos, Athanasios; Rouillard, Alexis; Pinto, Rui; Vourlidas, Angelos; Stenborg, Guillermo; Valette, Emeline; Howard, Russell; Hess, Phillip; Thernisien, Arnaud; Rich, Nathan; Griton, Lea; Indurain, Mikel; Raouafi, Nour-Edine; Lavarra, Michael; eville, Victor; 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 |
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; eville, 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; YEAR: 2020   DOI: 10.3847/1538-4365/ab61f4 |
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; 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; 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 |
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; 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 ... eville, 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; 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 |
2018 |
Parametric Decay and the Origin of the Low-frequency Alfv\ enic Spectrum of the Solar Wind The fast solar wind shows a wide spectrum of transverse magnetic and velocity field perturbations. These perturbations are strongly correlated in the sense of Alfv\ en waves propagating mostly outward, from the Sun to the interplanetary medium. They are likely to be fundamental to the acceleration and the heating of the solar wind. However, the precise origin of the broadband spectrum is unknown to date. Typical periods of chromospheric Alfv\ en waves are limited to a few minutes, and any longer period perturbations shoul ... eville, Victor; Tenerani, Anna; Velli, Marco; YEAR: 2018   DOI: 10.3847/1538-4357/aadb8f instabilities; magnetohydrodynamics: MHD; methods: numerical; parker solar probe; Solar Probe Plus; Solar wind; waves |
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