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Found 21 entries in the Bibliography.
Showing entries from 1 through 21
2022 |
An Extended and Fragmented Alfv\ en Zone in the Young Solar Wind Motivated by theoretical, numerical, and observational evidence, we explore the possibility that the critical transition between sub-Alfv\ enic flow and super-Alfv\ enic flow in the solar atmosphere takes place in fragmented and disconnected subvolumes within a general Alfv\ en critical zone. The initial observations of sub-Alfv\ enic periods by Parker Solar Probe near 16 R$_\ensuremath\odot$ do not yet provide sufficient evidence to distinguish this possibility from that of a folded surface that separates simply-connected r ... Chhiber, Rohit; Matthaeus, William; Usmanov, Arcadi; Bandyopadhyay, Riddhi; Goldstein, Melvyn; Published by: \mnras Published on: mar YEAR: 2022   DOI: 10.1093/mnras/stac779 |
2021 |
Simulation results from a global magnetohydrodynamic model of the solar corona and solar wind are compared with Parker Solar Probe (PSP) observations during its first five orbits. The fully three- dimensional model is based on Reynolds-averaged mean-flow equations coupled with turbulence-transport equations. The model includes the effects of electron heat conduction, Coulomb collisions, turbulent Reynolds stresses, and heating of protons and electrons via a turbulent cascade. Turbulence-transport equations for average turbul ... Chhiber, Rohit; Usmanov, Arcadi; Matthaeus, William; Goldstein, Melvyn; Published by: \apj Published on: dec YEAR: 2021   DOI: 10.3847/1538-4357/ac1ac7 Parker Data Used; 830; 1534; 824; 1483; 1477; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics |
Context. In 2020 May-June, six solar energetic ion events were observed by the Parker Solar Probe/IS⊙IS instrument suite at ≈0.35 AU from the Sun. From standard velocity-dispersion analysis, the apparent ion path length is ≈0.625 AU at the onset of each event. Chhiber, R.; Matthaeus, W.; Cohen, C.; Ruffolo, D.; Sonsrettee, W.; Tooprakai, P.; Seripienlert, A.; Chuychai, P.; Usmanov, A.; Goldstein, M.; McComas, D.; Leske, R.; Christian, E.; Mewaldt, R.; Labrador, A.; al., et; Published by: Astronomy and Astrophysics Published on: 06/2021 YEAR: 2021   DOI: "10.1051/0004-6361/202039816" |
The random walk of magnetic field lines is an important ingredient in understanding how the connectivity of the magnetic field affects the spatial transport and diffusion of charged particles. As solar energetic particles propagate away from near-solar sources, they interact with the fluctuating magnetic field, which modifies their distributions. We develop a formalism in which the differential equation describing the field line random walk contains both effects due to localized magnetic displacements and a non-stochastic co ... Chhiber, Rohit; Ruffolo, David; Matthaeus, William; Usmanov, Arcadi; Tooprakai, Paisan; Chuychai, Piyanate; Goldstein, Melvyn; Published by: The Astrophysical Journal Published on: 02/2021 YEAR: 2021   DOI: 10.3847/1538-4357/abd7f0 Parker Data Used; Solar energetic particles; interplanetary turbulence; interplanetary magnetic fields; Solar wind; 1491; 830; 824; 1534; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics |
2020 |
The Parker Solar Probe (PSP) mission has been studied since 1958. After many iterations and changes in design, the mission was launched on August 12, 2018 (see, https://www.nasa.gov/content/goddard/parker-solar-probe). PSP has completed its 3rd rendezvous with Venus and 6th perihelion passage. Each flyby brings PSP closer to the Sun (eventually to 9.7 solar radii). In October 2020 it flew within 20 solar radii of the solar surface. A goal of the mission is to determine how the solar corona is heated to ∼ a million degrees. ... Goldstein, Melvyn; Ruffolo, D.; Matthaeus, W.~H.; Chhiber, R.; Usmanov, A.~V.; Yang, Y.; Bandyopadhyay, R.; Parashar, T.~N.; DeForest, E.; Wan, M.; Chasapis, A.; Maruca, B.~A.; Velli, M.; Kasper, J.~C.; Published by: Radiation Effects and Defects in Solids Published on: 11/2020 YEAR: 2020   DOI: 10.1080/10420150.2020.1845690 |
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.; Published by: The Astrophysical Journal Published on: 10/2020 YEAR: 2020   DOI: 10.3847/1538-4357/abb594 |
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 |
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 |
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 |
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 |
2019 |
Highly structured slow solar wind emerging from an equatorial coronal hole During the solar minimum, when the Sun is at its least active, the solar wind is observed at high latitudes as a predominantly fast (more than 500 kilometres per second), highly Alfv\ enic rarefied stream of plasma originating from deep within coronal holes. Closer to the ecliptic plane, the solar wind is interspersed with a more variable slow wind of less than 500 kilometres per second. The precise origins of the slow wind streams are less certain; theories and observations suggest that they may originate at the tips of ... Bale, S.; Badman, S.; Bonnell, J.; Bowen, T.; Burgess, D.; Case, A.; Cattell, C.; Chandran, B.; Chaston, C.; Chen, C.; Drake, J.; de Wit, Dudok; Eastwood, J.; Ergun, R.; Farrell, W.; Fong, C.; Goetz, K.; Goldstein, M.; Goodrich, K.; Harvey, P.; Horbury, T.; Howes, G.; Kasper, J.; Kellogg, P.; Klimchuk, J.; Korreck, K.; Krasnoselskikh, V.; Krucker, S.; Laker, R.; Larson, D.; MacDowall, R.; Maksimovic, M.; Malaspina, D.; Martinez-Oliveros, J.; McComas, D.; Meyer-Vernet, N.; Moncuquet, M.; Mozer, F.; Phan, T.; Pulupa, M.; Raouafi, N.; Salem, C.; Stansby, D.; Stevens, M.; Szabo, A.; Velli, M.; Woolley, T.; Wygant, J.; Published by: Nature Published on: 12/2019 YEAR: 2019   DOI: 10.1038/s41586-019-1818-7 |
Contextual Predictions for the Parker Solar Probe . I. Critical Surfaces and Regions The solar corona and young solar wind may be characterized by critical surfaces\textemdashthe sonic, Alfv\ en, and first plasma-β unity surfaces\textemdashthat demarcate regions where the solar wind flow undergoes certain crucial transformations. Global numerical simulations and remote sensing observations offer a natural mode for the study of these surfaces at large scales, thus providing valuable context for the high-resolution in situ measurements expected from the recently launched Parker Solar Probe (PSP). The prese ... Chhiber, Rohit; Usmanov, Arcadi; Matthaeus, William; Goldstein, Melvyn; Published by: The Astrophysical Journal Supplement Series Published on: 03/2019 YEAR: 2019   DOI: 10.3847/1538-4365/ab0652 Astrophysics - Solar and Stellar Astrophysics; magnetohydrodynamics: MHD; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus; Solar wind; Sun: corona; turbulence |
2018 |
Usmanov, Arcadi; Matthaeus, William; Goldstein, Melvyn; Chhiber, Rohit; Published by: \apj Published on: 09/2018 YEAR: 2018   DOI: 10.3847/1538-4357/aad687 Parker Data Used; magnetohydrodynamics: MHD; methods: numerical; Solar wind; Sun: corona; Sun: rotation; turbulence |
Chhiber, Rohit; Usmanov, Arcadi; DeForest, Craig; Matthaeus, William; Parashar, Tulasi; Goldstein, Melvyn; Published by: \apjl Published on: 04/2018 YEAR: 2018   DOI: 10.3847/2041-8213/aab843 Parker Data Used; magnetohydrodynamics: MHD; Solar wind; Sun: corona; turbulence |
2017 |
Chhiber, R.; Subedi, P.; Usmanov, A.~V.; Matthaeus, W.~H.; Ruffolo, D.; Goldstein, M.~L.; Parashar, T.~N.; Published by: \apjs Published on: 06/2017 YEAR: 2017   DOI: 10.3847/1538-4365/aa74d2 Parker Data Used; cosmic rays; diffusion; methods: numerical; Solar wind; turbulence; Physics - Space Physics |
2016 |
The FIELDS Instrument Suite for Solar Probe Plus NASA\textquoterights Solar Probe Plus (SPP) mission will make the first in situ measurements of the solar corona and the birthplace of the solar wind. The FIELDS instrument suite on SPP will make direct measurements of electric and magnetic fields, the properties of in situ plasma waves, electron density and temperature profiles, and interplanetary radio emissions, amongst other things. Here, we describe the scientific objectives targeted by the SPP/FIELDS instrument, the instrument design itself, and the instrument conce ... Bale, S.; Goetz, K.; Harvey, P.; Turin, P.; Bonnell, J.; de Wit, T.; Ergun, R.; MacDowall, R.; Pulupa, M.; Andre, M.; Bolton, M.; Bougeret, J.-L.; Bowen, T.; Burgess, D.; Cattell, C.; Chandran, B.; Chaston, C.; Chen, C.; Choi, M.; Connerney, J.; Cranmer, S.; Diaz-Aguado, M.; Donakowski, W.; Drake, J.; Farrell, W.; Fergeau, P.; Fermin, J.; Fischer, J.; Fox, N.; Glaser, D.; Goldstein, M.; Gordon, D.; Hanson, E.; Harris, S.; Hayes, L.; Hinze, J.; Hollweg, J.; Horbury, T.; Howard, R.; Hoxie, V.; Jannet, G.; Karlsson, M.; Kasper, J.; Kellogg, P.; Kien, M.; Klimchuk, J.; Krasnoselskikh, V.; Krucker, S.; Lynch, J.; Maksimovic, M.; Malaspina, D.; Marker, S.; Martin, P.; Martinez-Oliveros, J.; McCauley, J.; McComas, D.; McDonald, T.; Meyer-Vernet, N.; Moncuquet, M.; Monson, S.; Mozer, F.; Murphy, S.; Odom, J.; Oliverson, R.; Olson, J.; Parker, E.; Pankow, D.; Phan, T.; Quataert, E.; Quinn, T.; Ruplin, S.; Salem, C.; Seitz, D.; Sheppard, D.; Siy, A.; Stevens, K.; Summers, D.; Szabo, A.; Timofeeva, M.; Vaivads, A.; Velli, M.; Yehle, A.; Werthimer, D.; Wygant, J.; Published by: Space Science Reviews Published on: 12/2016 YEAR: 2016   DOI: 10.1007/s11214-016-0244-5 Coronal heating; Parker Data Used; parker solar probe; Solar Probe Plus |
SOLAR WIND COLLISIONAL AGE FROM A GLOBAL MAGNETOHYDRODYNAMICS SIMULATION Simple estimates of the number of Coulomb collisions experienced by the interplanetary plasma to the point of observation, I.e., the \textquotedblleftcollisional age\textquotedblright, can be usefully employed in the study of non-thermal features of the solar wind. Usually these estimates are based on local plasma properties at the point of observation. Here we improve the method of estimation of the collisional age by employing solutions obtained from global three-dimensional magnetohydrodynamics simulations. This enable ... Chhiber, R; Usmanov, AV; Matthaeus, WH; Goldstein, ML; Published by: The Astrophysical Journal Published on: 04/2016 YEAR: 2016   DOI: 10.3847/0004-637X/821/1/34 magnetohydrodynamics: MHD; methods: numerical; parker solar probe; plasmas; scattering; Solar Probe Plus; Solar wind; turbulence |
Usmanov, Arcadi; Goldstein, Melvyn; Matthaeus, William; Published by: \apj Published on: 03/2016 YEAR: 2016   DOI: 10.3847/0004-637X/820/1/17 Parker Data Used; ISM: magnetic fields; magnetohydrodynamics: MHD; methods: numerical; Solar wind; Sun: heliosphere; turbulence |
2015 |
The Solar Wind Electrons Alphas and Protons (SWEAP) Investigation on Solar Probe Plus is a four sensor instrument suite that provides complete measurements of the electrons and ionized helium and hydrogen that constitute the bulk of solar wind and coronal plasma. SWEAP consists of the Solar Probe Cup (SPC) and the Solar Probe Analyzers (SPAN). SPC is a Faraday Cup that looks directly at the Sun and measures ion and electron fluxes and flow angles as a function of energy. SPAN consists of an ion and electron electrostatic ... Kasper, Justin; Abiad, Robert; Austin, Gerry; Balat-Pichelin, Marianne; Bale, Stuart; Belcher, John; Berg, Peter; Bergner, Henry; Berthomier, Matthieu; Bookbinder, Jay; Brodu, Etienne; Caldwell, David; Case, Anthony; Chandran, Benjamin; Cheimets, Peter; Cirtain, Jonathan; Cranmer, Steven; Curtis, David; Daigneau, Peter; Dalton, Greg; Dasgupta, Brahmananda; DeTomaso, David; Diaz-Aguado, Millan; Djordjevic, Blagoje; Donaskowski, Bill; Effinger, Michael; Florinski, Vladimir; Fox, Nichola; Freeman, Mark; Gallagher, Dennis; Gary, Peter; Gauron, Tom; Gates, Richard; Goldstein, Melvin; Golub, Leon; Gordon, Dorothy; Gurnee, Reid; Guth, Giora; Halekas, Jasper; Hatch, Ken; Heerikuisen, Jacob; Ho, George; Hu, Qiang; Johnson, Greg; Jordan, Steven; Korreck, Kelly; Larson, Davin; Lazarus, Alan; Li, Gang; Livi, Roberto; Ludlam, Michael; Maksimovic, Milan; McFadden, James; Marchant, William; Maruca, Bennet; McComas, David; Messina, Luciana; Mercer, Tony; Park, Sang; Peddie, Andrew; Pogorelov, Nikolai; Reinhart, Matthew; Richardson, John; Robinson, Miles; Rosen, Irene; Skoug, Ruth; Slagle, Amanda; Steinberg, John; Stevens, Michael; Szabo, Adam; Taylor, Ellen; Tiu, Chris; Turin, Paul; Velli, Marco; Webb, Gary; Whittlesey, Phyllis; Wright, Ken; Wu, S.; Zank, Gary; Published by: Space Science Reviews Published on: 10/2015 YEAR: 2015   DOI: 10.1007/s11214-015-0206-3 Acceleration; Corona; Heating; Parker Data Used; Solar Probe Plus; Solar wind plasma; SWEAP |
2013 |
Intermittent Heating in Solar Wind and Kinetic Simulations Wu, P.; Perri, S.; Osman, K.; Wan, M.; Matthaeus, W.~H.; Shay, M.~A.; Goldstein, M.~L.; Karimabadi, H.; Chapman, S.; Published by: \apjl Published on: 02/2013 YEAR: 2013   DOI: 10.1088/2041-8205/763/2/L30 Parker Data Used; magnetohydrodynamics: MHD; Solar wind; Sun: corona; turbulence |
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