|
Notice:
|
Found 24 entries in the Bibliography.
Showing entries from 1 through 24
| 2022 |
|
The Dynamic Structure of Coronal Hole Boundaries The boundaries of solar coronal holes are difficult to uniquely define observationally but are sites of interest in part because the slow solar wind appears to originate there. The aim of this article is to explore the dynamics of interchange magnetic reconnection at different types of coronal hole boundaries- namely streamers and pseudostreamers-and their implications for the coronal structure. We describe synthetic observables derived from three-dimensional magnetohydrodynamic simulations of the atmosphere of the Sun in wh ... Aslanyan, V.; Pontin, D.~I.; Scott, R.~B.; Higginson, A.~K.; Wyper, P.~F.; Antiochos, S.~K.; Published by: \apj Published on: jun YEAR: 2022 DOI: 10.3847/1538-4357/ac69ed Parker Data Used; Solar Physics; Solar magnetic reconnection; Solar corona; Solar coronal holes; Slow solar wind; Magnetohydrodynamics; 1476; 1504; 1483; 1484; 1873; 1964 |
|
Constraining Global Coronal Models with Multiple Independent Observables Global coronal models seek to produce an accurate physical representation of the Sun s atmosphere that can be used, for example, to drive space-weather models. Assessing their accuracy is a complex task, and there are multiple observational pathways to provide constraints and tune model parameters. Here, we combine several such independent constraints, defining a model- agnostic framework for standardized comparison. We require models to predict the distribution of coronal holes at the photosphere, and neutral line topology ... Badman, Samuel; Brooks, David; Poirier, Nicolas; Warren, Harry; Petrie, Gordon; Rouillard, Alexis; Arge, Nick; Bale, Stuart; Agüero, Diego; Harra, Louise; Jones, Shaela; Kouloumvakos, Athanasios; Riley, Pete; Panasenco, Olga; Velli, Marco; Wallace, Samantha; Published by: \apj Published on: jun YEAR: 2022 DOI: 10.3847/1538-4357/ac6610 Parker Data Used; Solar Physics; Solar corona; Solar coronal holes; Astronomical models; 1476; 1483; 1484; 86; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
|
Parker Solar Probe (PSP) and SolO data are utilized to investigate magnetic field intermittency in the solar wind (SW). Small-scale intermittency (20-100 d $_ i $) is observed to radially strengthen when methods relying on higher-order moments are considered (SF$_ q $; SDK), but no clear trend is observed at larger scales. However, lower-order moment-based methods (e.g., partial variance of increments; PVI) are deemed more appropriate for examining the evolution of the bulk of coherent structures (CSs), PVI \ensuremath\geq 3 ... Sioulas, Nikos; Huang, Zesen; Velli, Marco; Chhiber, Rohit; Cuesta, Manuel; Shi, Chen; Matthaeus, William; Bandyopadhyay, Riddhi; Vlahos, Loukas; Bowen, Trevor; Qudsi, Ramiz; Bale, Stuart; Owen, Christopher; Louarn, P.; Fedorov, A.; c, Milan; Stevens, Michael; Case, Anthony; Kasper, Justin; Larson, Davin; Pulupa, Marc; Livi, Roberto; Published by: \apj Published on: aug YEAR: 2022 DOI: 10.3847/1538-4357/ac7aa2 Parker Data Used; Solar wind; interplanetary turbulence; Magnetohydrodynamics; Space plasmas; Plasma astrophysics; Solar Physics; 1534; 830; 1964; 1544; 1261; 1476; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
|
The Dynamic Coupling of Streamers and Pseudostreamers to the Heliosphere The slow solar wind is generally believed to result from the interaction of open and closed coronal magnetic flux at streamers and pseudostreamers. We use three-dimensional magnetohydrodynamic simulations to determine the detailed structure and dynamics of open-closed interactions that are driven by photospheric convective flows. The photospheric magnetic field model includes a global dipole giving rise to a streamer together with a large parasitic polarity region giving rise to a pseudostreamer that separates a satellite co ... Aslanyan, V.; Pontin, D.~I.; Higginson, A.~K.; Wyper, P.~F.; Scott, R.~B.; Antiochos, S.~K.; Published by: \apj Published on: apr YEAR: 2022 DOI: 10.3847/1538-4357/ac5d5b Parker Data Used; Solar Physics; Solar magnetic reconnection; Solar corona; Solar coronal holes; Magnetohydrodynamics; Slow solar wind; 1476; 1504; 1483; 1484; 1964; 1873; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
|
The physical properties responsible for the formation and evolution of the corona and heliosphere are still not completely understood. 3D MHD global modeling is a powerful tool to investigate all the possible candidate processes. To fully understand the role of each of them, we need a validation process where the output from the simulations is quantitatively compared to the observational data. In this work, we present the results from our validation process applied to the wave turbulence driven 3D MHD corona-wind model WindP ... Parenti, Susanna; eville, Victor; Brun, Allan; Pinto, Rui; Auchère, Fr\; Buchlin, Eric; Perri, Barbara; Strugarek, Antoine; Published by: \apj Published on: apr YEAR: 2022 DOI: 10.3847/1538-4357/ac56da Parker Data Used; Magnetohydrodynamical simulations; Solar Physics; Solar coronal heating; Solar coronal streamers; Solar corona; Solar extreme ultraviolet emission; Solar radiation; Solar atmosphere; 1966; 1476; 1989; 1486; 1483; 1493; 1521; 1477; Astrophysics - Solar and Stellar Astrophysics |
| 2021 |
|
Parker Solar Probe (PSP) data recorded within a heliocentric radial distance of 0.3 au have revealed a magnetic field dominated by Alfv\ enic structures that undergo large local variations or even reversals of the radial magnetic field. They are called magnetic switchbacks, they are consistent with folds in magnetic field lines within a same magnetic sector and are associated with velocity spikes during an otherwise calmer background. They are thought to originate either in the low solar atmosphere through magnetic reconnect ... Fargette, Na; Lavraud, Benoit; Rouillard, Alexis; eville, Victor; de Wit, Thierry; Froment, Clara; Halekas, Jasper; Phan, Tai; Malaspina, David; Bale, Stuart; Kasper, Justin; Louarn, Philippe; Case, Anthony; Korreck, Kelly; Larson, Davin; Pulupa, Marc; Stevens, Michael; Whittlesey, Phyllis; Berthomier, Matthieu; Published by: \apj Published on: oct YEAR: 2021 DOI: 10.3847/1538-4357/ac1112 Solar wind; Solar Physics; Wavelet analysis; Supergranulation; Solar granulation; Solar magnetic fields; 1534; 1476; 1918; 1662; 1498; 1503; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used |
|
Switchback Boundary Dissipation and Relative Age We examine Parker Solar Probe (PSP) magnetic field and plasma observations during its first encounter with the Sun in early 2018 November. During this perihelion time, impulsive reversals in the magnetic field, called switchbacks, were found in the data set characterized by a quick rotation in B along with a simultaneous increase in solar wind flow. In this work, we examine the structure and morphology of 920 switchback boundaries as PSP enters and exits the structures, specifically looking for evidence of boundary degra ... Farrell, W.~M.; Rasca, A.~P.; MacDowall, R.~J.; Gruesbeck, J.~R.; Bale, S.~D.; Kasper, J.~C.; Published by: \apj Published on: jul YEAR: 2021 DOI: 10.3847/1538-4357/ac005b Parker Data Used; Solar wind; Solar Physics; Solar magnetic flux emergence; Solar magnetic fields; 1534; 1476; 2000; 1503 |
|
Various forms of exact laws governing magnetohydrodynamic (MHD) turbulence have been derived either in the incompressibility limit, or for isothermal compressible flows. Here we propose a more general method that allows us to obtain such laws for any turbulent isentropic flow (i.e., constant entropy). We demonstrate that the known MHD exact laws (incompressible and isothermal) and the new (polytropic) one can be obtained as specific cases of the general law when the corresponding closure equation is stated. We also recover a ... Published by: \apj Published on: jul YEAR: 2021 DOI: 10.3847/1538-4357/ac0337 Solar wind; Solar Physics; Parker Data Used; Magnetohydrodynamics; Plasma astrophysics; Plasma physics; interplanetary turbulence; 1534; 1476; 1964; 1261; 2089; 830; Physics - Plasma Physics; Physics - Fluid Dynamics |
|
Space weather: the solar perspective The Sun, as an active star, is the driver of energetic phenomena that structure interplanetary space and affect planetary atmospheres. The effects of Space Weather on Earth and the solar system is of increasing importance as human spaceflight is preparing for lunar and Mars missions. This review is focusing on the solar perspective of the Space Weather relevant phenomena, coronal mass ejections (CMEs), flares, solar energetic particles (SEPs), and solar wind stream interaction regions (SIR). With the advent of the STEREO mis ... Published by: Living Reviews in Solar Physics Published on: dec YEAR: 2021 DOI: 10.1007/s41116-021-00030-3 Parker Data Used; space weather; Solar Physics; CMEs; flares; SEPs; Dynamic corona; magnetic field; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
|
The Formation and Lifetime of Outflows in a Solar Active Region Active regions are thought to be one contributor to the slow solar wind. Upflows in EUV coronal spectral lines are routinely observed at their boundaries, and provide the most direct way for upflowing material to escape into the heliosphere. The mechanisms that form and drive these upflows, however, remain to be fully characterized. It is unclear how quickly they form, or how long they exist during their lifetimes. They could be initiated low in the atmosphere during magnetic flux emergence, or as a response to processes occ ... Brooks, David; Harra, Louise; Bale, Stuart; Barczynski, Krzysztof; Mandrini, Cristina; Polito, Vanessa; Warren, Harry; Published by: \apj Published on: aug YEAR: 2021 DOI: 10.3847/1538-4357/ac0917 Solar Physics; Slow solar wind; Solar active regions; Solar energetic particles; 1476; 1873; 1974; 1491; Astrophysics - Solar and Stellar Astrophysics; Parker Data Used |
|
Near-Sun Switchback Boundaries: Dissipation with Solar Distance The most surprising result from the first solar encounters by the Parker Solar Probe (PSP) is the large amount of brief magnetic field reversals often referred to as switchbacks. Switchbacks have previously been observed further downstream in the solar wind by spacecraft such as Helios 2 at 62 R$_s$ from the Sun. However, these observations lack a distinct proton temperature increase detected inside switchbacks by PSP, implying that they are evolving over time to eventually reach a pressure balance at the switchback boundari ... Rasca, Anthony; Farrell, William; MacDowall, Robert; Bale, Stuart; Kasper, Justin; Published by: \apj Published on: aug YEAR: 2021 DOI: 10.3847/1538-4357/ac079f The Sun; Solar wind; Solar Physics; 1693; 1534; 1476; Parker Data Used |
|
The Dynamic Formation of Pseudostreamers Streamers and pseudostreamers structure the corona at the largest scales, as seen in both eclipse and coronagraph white-light images. Their inverted-goblet appearance encloses broad coronal loops at the Sun and tapers to a narrow radial stalk away from the star. The streamer associated with the global solar dipole magnetic field is long-lived, predominantly contains a single arcade of nested loops within it, and separates opposite-polarity interplanetary magnetic fields with the heliospheric current sheet (HCS) anchored at i ... Scott, Roger; Pontin, David; Antiochos, Spiro; DeVore, Richard; Wyper, Peter; Published by: The Astrophysical Journal Published on: 05/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abec4f Solar Physics; Solar magnetic reconnection; Solar wind; 1476; 1504; 1534; Parker Data Used |
|
First Observations of Anomalous Cosmic Rays in to 36 Solar Radii NASA s Parker Solar Probe mission continues to travel closer to the Sun than any prior human-made object, with an expected closest approach of <10 solar radii (<0.046 au) by 2024. On board, the Integrated Science Investigation of the Sun instrument suite makes unprecedented in situ measurements of energetic particles in the near-Sun environment. The current low level of solar activity offers a prime opportunity to measure cosmic rays closer to the Sun than ever before. We present the first observations of anomalous cosmic ra ... Rankin, J.; McComas, D.; Leske, R.; Christian, E.; Cohen, C.; Cummings, A.; Joyce, C.; Labrador, A.; Mewaldt, R.; Posner, A.; Schwadron, N.; Strauss, R.; Stone, E.; Wiedenbeck, M.; Published by: The Astrophysical Journal Published on: 05/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abec7e cosmic rays; Solar wind; Heliosphere; Solar energetic particles; Solar Physics; solar cycle; Quiet Sun; Particle astrophysics; interplanetary magnetic fields; Plasma astrophysics; Interplanetary particle acceleration; Pickup ions; 329; 1534; 711; 1491; 1476; 1487; 1322; 96; 824; 1261; 826; 1239; Parker Data Used |
|
Could Switchbacks Originate in the Lower Solar Atmosphere? I. Formation Mechanisms of Switchbacks The recent rediscovery of magnetic field switchbacks or deflections embedded in the solar wind flow by the Parker Solar Probe mission lead to a huge interest in the modeling of the formation mechanisms and origin of these switchbacks. Several scenarios for their generation were put forth, ranging from lower solar atmospheric origins by reconnection, to being a manifestation of turbulence in the solar wind, and so on. Here we study some potential formation mechanisms of magnetic switchbacks in the lower solar atmosphere, usin ... Magyar, Norbert; Utz, Dominik; Erdélyi, Robertus; Nakariakov, Valery; Published by: The Astrophysical Journal Published on: 04/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abec49 Parker Data Used; Solar atmosphere; Solar Physics; Magnetohydrodynamics; 1477; 1476; 1964; Astrophysics - Solar and Stellar Astrophysics |
|
After the launch of STEREO twin spacecraft, and most recently of Solar Orbiter and Parker Solar Probe spacecraft, the next mission that will explore Sun-Earth interactions and how the Sun modulates the Heliosphere will be the "Lagrange" mission, which will consist of two satellites placed in orbit around L1 and L5 Sun-Earth Lagrangian points. Despite the significant novelties that will be provided by such a double vantage point, there will be also missing information, that are briefly discussed here. For future heliospheric ... Published by: Frontiers in Astronomy and Space Sciences Published on: 03/2021 YEAR: 2021 DOI: 10.3389/fspas.2021.627576 space weather; Future missions; open problems; Solar Physics; Solar eruptions |
|
Characteristics of Magnetic Holes in the Solar Wind Revealed by Parker Solar Probe Yu, L.; Huang, S.~Y.; Yuan, Z.~G.; Jiang, K.; Xiong, Q.~Y.; Xu, S.~B.; Wei, Y.~Y.; Zhang, J.; Zhang, Z.~H.; Published by: \apj Published on: 02/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abb9a8 Solar wind; Solar Physics; interplanetary magnetic fields; Solar magnetic fields; 1534; 1476; 824; 1503; Physics - Space Physics; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics |
|
Whistlers in the Solar Vicinity That Are Spiky in Time and Frequency Mozer, F.~S.; Bonnell, J.~W.; Halekas, J.~S.; Rahmati, A.; Schum, G.; Vasko, I.~V.; Published by: \apj Published on: 02/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abce59 Solar wind; Solar Physics; Solar electromagnetic emission; 1534; 1476; 1490 |
| 2020 |
|
The Parker Solar Probe (PSP) and Solar Orbiter missions are designed to make groundbreaking observations of the Sun and interplanetary space within this decade. We show that a particularly interesting in situ observation of an interplanetary coronal mass ejection (ICME) by PSP may arise during close solar flybys (<0.1 au). During these times, the same magnetic flux rope inside an ICME could be observed in situ by PSP twice, by impacting its frontal part as well as its leg. Investigating the odds of this situation, we forecas ... Möstl, Christian; Weiss, Andreas; Bailey, Rachel; Reiss, Martin; Amerstorfer, Tanja; Hinterreiter, Jürgen; Bauer, Maike; McIntosh, Scott; Lugaz, No\; Stansby, David; Published by: The Astrophysical Journal Published on: 11/2020 YEAR: 2020 DOI: 10.3847/1538-4357/abb9a1 Solar coronal mass ejection; Solar storm; Ejecta; space weather; Solar system; Solar wind; Solar Physics; interplanetary magnetic fields; Solar magnetic fields |
|
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.; Published by: The Astrophysical Journal Published on: 10/2020 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 |
|
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; Published by: The Astrophysical Journal Published on: 10/2020 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 |
|
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; Published by: The Astrophysical Journal Published on: 09/2020 YEAR: 2020 DOI: 10.3847/1538-4357/abaaae Parker Data Used; parker solar probe; Solar Physics; Solar Probe Plus; Solar wind; Space plasmas |
|
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.; Published by: The Astrophysical Journal Supplement Series Published on: 08/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab9eba Parker Data Used; parker solar probe; Solar Physics; Solar Probe Plus; Solar wind; The Sun |
| 2012 |
|
A method to estimate the total fluence of solar flare neutrons at a spacecraft traveling in the innermost part of the heliosphere (at heliocentric radial distances of \<1 AU) is presented. The results of the neutron production and emissivity codes of Hua and Lingenfelter (1987a, 1987b) scaled to one of the largest solar neutron events ever observed at the Earth are used to derive a conservative estimate of the energy spectrum of neutrons emitted from the Sun after a large solar flare. By taking into account the surviva ... Published by: Space Weather Published on: 03/2012 YEAR: 2012 DOI: 10.1029/2011SW000732 and Astronomy: Flares; and Astronomy: General or miscellaneous; and Astronomy: X-rays; and neutrinos; Astrophysics; gamma rays; parker solar probe; Solar Physics; Solar Probe Plus |
| 2011 |
|
Statistical association of discontinuities and reconnection in magnetohydrodynamic turbulence Servidio, S.; Greco, A.; Matthaeus, W.~H.; Osman, K.~T.; Dmitruk, P.; Published by: Journal of Geophysical Research (Space Physics) Published on: 09/2011 YEAR: 2011 DOI: 10.1029/2011JA016569 Parker Data Used; Interplanetary Physics: Discontinuities (7811); Interplanetary Physics: Solar wind plasma; Nonlinear Geophysics: Turbulence (3379; 4568; 7863); Solar Physics; Astrophysics; and Astronomy: Magnetic reconnection (2723; 7835) |
1
