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Authors: Kuznetsov V.D.
Title: Solar and heliospheric space missions
Abstract:

The paper provides a review of the state of the art and prospects of space research in heliophysics, in which a pivotal role belongs to magnetic measurements in the Sun and heliosphere. New space missions, such as the Interhelioprobe, Solar Orbiter, Solar Probe Plus, etc., will follow the currently operating ones (Hinode, SDO, STEREO, etc.) to observe the Sun from short distances and from out-of-ecliptic positions, as well as to conduct in situ measurements in the vicinity of the Sun and outside the ecliptic. The planned coordinated observations within the framework of these missions will allow us to explore the structure and dynamics of magnetic fields in the polar regions of the Sun, to study the mechanisms of the solar dynamo and solar cycle, to gain a deeper insight into the process. . .
Date: 02/2015 Publisher: Advances in Space Research Pages: 879 - 885 DOI: 10.1016/j.asr.2014.07.034 Available at: https://linkinghub.elsevier.com/retrieve/pii/S0273117714004906https://api.elsevier.com/content/article/PII:S0273117714004906?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0273117714004906?httpAccept=text/plain
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Authors: Kuznetsov V.D.
Title: Solar and heliospheric space missions
Abstract:

The paper provides a review of the state of the art and prospects of space research in heliophysics, in which a pivotal role belongs to magnetic measurements in the Sun and heliosphere. New space missions, such as the Interhelioprobe, Solar Orbiter, Solar Probe Plus, etc., will follow the currently operating ones (Hinode, SDO, STEREO, etc.) to observe the Sun from short distances and from out-of-ecliptic positions, as well as to conduct in situ measurements in the vicinity of the Sun and outside the ecliptic. The planned coordinated observations within the framework of these missions will allow us to explore the structure and dynamics of magnetic fields in the polar regions of the Sun, to study the mechanisms of the solar dynamo and solar cycle, to gain a deeper insight into the process. . .
Date: 02/2015 Publisher: Advances in Space Research Pages: 879 - 885 DOI: 10.1016/j.asr.2014.07.034 Available at: https://linkinghub.elsevier.com/retrieve/pii/S0273117714004906https://api.elsevier.com/content/article/PII:S0273117714004906?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0273117714004906?httpAccept=text/plain
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Authors: Krupar Vratislav, Szabo Adam, Maksimovic Milan, Kruparova Oksana, Kontar Eduard P., et al.
Title: Density Fluctuations in the Solar Wind Based on Type III Radio Bursts Observed by Parker Solar Probe
Abstract:

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 Solar Probe (PSP). For the first time, we retrieved type III burst decay times, τ d  τd , between 1 and 10 MHz thanks to an unparalleled temporal resolution of PSP. We observed a significant deviation in a power-law slope for frequencies above 1 MHz. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 57 DOI: 10.3847/1538-4365/ab65bd Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab65bd
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Authors: Krupar Vratislav, Szabo Adam, Maksimovic Milan, Kruparova Oksana, Kontar Eduard P., et al.
Title: Density Fluctuations in the Solar Wind Based on Type III Radio Bursts Observed by Parker Solar Probe
Abstract:

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 Solar Probe (PSP). For the first time, we retrieved type III burst decay times, τ d  τd , between 1 and 10 MHz thanks to an unparalleled temporal resolution of PSP. We observed a significant deviation in a power-law slope for frequencies above 1 MHz. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 57 DOI: 10.3847/1538-4365/ab65bd Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab65bd
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Authors: Krasnoselskikh V., Larosa A., Agapitov O., de Wit Dudok, Moncuquet M., et al.
Title: Localized Magnetic-field Structures and Their Boundaries in the Near-Sun Solar Wind from Parker Solar Probe Measurements
Abstract:

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. Alfvénic structure, where the variations of the magnetic field components take place while conserving the magnitude of the magnetic field; II. Compressional structure, where the magnitude of the field varies together with changes of its components; and III. Structure manifesting full reversal of the magnetic field, presumably . . .
Date: 04/2020 Publisher: The Astrophysical Journal Pages: 93 DOI: 10.3847/1538-4357/ab7f2d Available at: https://iopscience.iop.org/article/10.3847/1538-4357/ab7f2d
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Authors: Krasnoselskikh V., Larosa A., Agapitov O., de Wit Dudok, Moncuquet M., et al.
Title: Localized Magnetic-field Structures and Their Boundaries in the Near-Sun Solar Wind from Parker Solar Probe Measurements
Abstract:

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. Alfvénic structure, where the variations of the magnetic field components take place while conserving the magnitude of the magnetic field; II. Compressional structure, where the magnitude of the field varies together with changes of its components; and III. Structure manifesting full reversal of the magnetic field, presumably . . .
Date: 04/2020 Publisher: The Astrophysical Journal Pages: 93 DOI: 10.3847/1538-4357/ab7f2d Available at: https://iopscience.iop.org/article/10.3847/1538-4357/ab7f2d
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Authors: Kouloumvakos Athanasios, Vourlidas Angelos, Rouillard Alexis P., Roelof Edmond C., Leske Rick, et al.
Title: The Solar Origin of Particle Events Measured by Parker Solar Probe
Abstract:

During the second solar encounter phase of Parker Solar Probe (PSP), two small solar energetic particle (SEP) events were observed by the Integrated Science Investigation of the Sun, on 2019 April 2 and 4. At the time, PSP was approaching its second perihelion at a distance of ∼24.8 million kilometers from the solar center, it was in near-radial alignment with STEREO-A and in quadrature with Earth. During the two SEP events multiple narrow ejections and a streamer-blowout coronal mass ejection (SBO-CME) originated from a solar region situated eastward of PSP. We analyze remote-sensing observations of the solar corona, and model the different eruptions and how PSP was connected magnetically to the solar atmosphere to determine the possible origin of the two SEP events. We find that the. . .
Date: 08/2020 Publisher: The Astrophysical Journal Pages: 107 DOI: 10.3847/1538-4357/aba5a1 Available at: https://iopscience.iop.org/article/10.3847/1538-4357/aba5a1https://iopscience.iop.org/article/10.3847/1538-4357/aba5a1/
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Authors: Korreck Kelly E., Kasper Justin C., Case Anthony W., Daigneau Peter, Bookbinder Jay A., et al.
Title: SPIE ProceedingsSolar Wind Electrons Alphas and Protons (SWEAP) Science Operations Center initial design and implementation
Abstract:

Solar Probe Plus, scheduled to launch in 2018, is a NASA mission that will fly through the Sun’s atmosphere for the first time. It will employ a combination of in situ plasma measurements and remote sensing imaging to achieve the mission’s primary goal: to understand how the Sun’s corona is heated and how the solar wind is accelerated. The Solar Wind Electrons Alphas and Protons (SWEAP) instrument suite consists of a Faraday cup and three electrostatic analyzers. In order to accomplish the science objectives, an encounter-based operations scheme is needed. This paper will outline the SWEAP science operations center design and schemes for data selection and down link. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permi. . .
Date: Publisher: SPIE DOI: 10.1117/12.2057314 Available at: http://proceedings.spiedigitallibrary.org/proceeding.aspx?doi=10.1117/12.2057314
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Authors: Korreck Kelly E., Szabo Adam, Chinchilla Teresa Nieves, Lavraud Benoit, Luhmann Janet, et al.
Title: Source and Propagation of a Streamer Blowout Coronal Mass Ejection Observed by the Parker Solar Probe
Abstract:

In the first orbit of the Parker Solar Probe (PSP), in situ thermal plasma and magnetic field measurements were collected as close as 35 RSun from the Sun, an environment that had not been previously explored. During the first orbit of PSP, the spacecraft flew through a streamer blowout coronal mass ejection (SBO-CME) on 2018 November 11 at 23:50 UT as it exited the science encounter. The SBO-CME on November 11 was directed away from the Earth and was not visible by L1 or Earth-based telescopes due to this geometric configuration. However, PSP and the STEREO-A spacecraft were able to make observations of this slow (v ≈ 380 km s-1) SBO-CME. Using the PSP data, STEREO-A images, and Wang-Sheeley-Arge model, the source region of the CME is found to be a helmet stream. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 69 DOI: 10.3847/1538-4365/ab6ff9 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab6ff9
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Authors: Korreck Kelly E., Szabo Adam, Chinchilla Teresa Nieves, Lavraud Benoit, Luhmann Janet, et al.
Title: Source and Propagation of a Streamer Blowout Coronal Mass Ejection Observed by the Parker Solar Probe
Abstract:

In the first orbit of the Parker Solar Probe (PSP), in situ thermal plasma and magnetic field measurements were collected as close as 35 RSun from the Sun, an environment that had not been previously explored. During the first orbit of PSP, the spacecraft flew through a streamer blowout coronal mass ejection (SBO-CME) on 2018 November 11 at 23:50 UT as it exited the science encounter. The SBO-CME on November 11 was directed away from the Earth and was not visible by L1 or Earth-based telescopes due to this geometric configuration. However, PSP and the STEREO-A spacecraft were able to make observations of this slow (v ≈ 380 km s−1) SBO-CME. Using the PSP data, STEREO-A images, and Wang─Sheeley─Arge model, the source region of the CME is found to be a helmet . . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 69 DOI: 10.3847/1538-4365/ab6ff9 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab6ff9
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Authors: Korendyke Clarence M., Vourlidas Angelos, Plunkett Simon P., Howard Russell A., Wang Dennis, et al.
Title: SPIE ProceedingsDevelopment and test of an active pixel sensor detector for heliospheric imager on solar orbiter and solar probe plus
Abstract: N/A
Date: 10/2013 Publisher: SPIE DOI: 10.1117/12.2027655 Available at: http://proceedings.spiedigitallibrary.org/proceeding.aspx?doi=10.1117/12.2027655
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Authors: Korendyke Clarence M., Vourlidas Angelos, Plunkett Simon P., Howard Russell A., Wang Dennis, et al.
Title: SPIE ProceedingsDevelopment and test of an active pixel sensor detector for heliospheric imager on solar orbiter and solar probe plus
Abstract: N/A
Date: 10/2013 Publisher: SPIE DOI: 10.1117/12.2027655 Available at: http://proceedings.spiedigitallibrary.org/proceeding.aspx?doi=10.1117/12.2027655
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Authors: Kong Xiangliang, Guo Fan, Giacalone Joe, Li Hui, and Chen Yao
Title: The Acceleration of High-energy Protons at Coronal Shocks: The Effect of Large-scale Streamer-like Magnetic Field Structures
Abstract:

Recent observations have shown that coronal shocks driven by coronal mass ejections can develop and accelerate particles within several solar radii in large solar energetic particle (SEP) events. Motivated by this, we present an SEP acceleration study that including the process in which a fast shock propagates through a streamer-like magnetic field with both closed and open field lines in the low corona region. The acceleration of protons is modeled by numerically solving the Parker transport equation with spatial diffusion both along and across the magnetic field. We show that particles can be sufficiently accelerated to up to several hundred MeV within 2-3 solar radii. When the shock propagates through a streamer-like magnetic field, particles are more efficiently accelerated compared. . .
Date: 12/2017 Publisher: The Astrophysical Journal Pages: 38 DOI: 10.3847/1538-4357/aa97d7 Available at: http://stacks.iop.org/0004-637X/851/i=1/a=38?key=crossref.2009ec10fbd1f6f8cd1462070076984f
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Authors: Kong Xiangliang, Guo Fan, Giacalone Joe, Li Hui, and Chen Yao
Title: The Acceleration of High-energy Protons at Coronal Shocks: The Effect of Large-scale Streamer-like Magnetic Field Structures
Abstract:

Recent observations have shown that coronal shocks driven by coronal mass ejections can develop and accelerate particles within several solar radii in large solar energetic particle (SEP) events. Motivated by this, we present an SEP acceleration study that including the process in which a fast shock propagates through a streamer-like magnetic field with both closed and open field lines in the low corona region. The acceleration of protons is modeled by numerically solving the Parker transport equation with spatial diffusion both along and across the magnetic field. We show that particles can be sufficiently accelerated to up to several hundred MeV within 2-3 solar radii. When the shock propagates through a streamer-like magnetic field, particles are more efficiently accelerated compared. . .
Date: 12/2017 Publisher: The Astrophysical Journal Pages: 38 DOI: 10.3847/1538-4357/aa97d7 Available at: http://stacks.iop.org/0004-637X/851/i=1/a=38?key=crossref.2009ec10fbd1f6f8cd1462070076984f
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Authors: Kombiadou Katerina, Ganthy Florian, Verney Romaric, Plus Martin, and Sottolichio Aldo
Title: Modelling the effects of Zostera noltei meadows on sediment dynamics: application to the Arcachon lagoon
Abstract:

A three-dimensional model has been modified to describe the complex interactions between hydrodynamics, sediment dynamics and biological parameters in the presence of Zostera noltei. The model treats seagrass leafs as flexible blades that bend under hydrodynamic forcing and alter the local momentum and turbulence fluxes and, therefore, the benthic shear conditions; these changes cause related changes to the mass balance at the boundary of the bed, in turn affecting the suspended matter in the column and ultimately primary productivity and the growth of the dwarf-grass. Modelling parameters related to the impact of Z. noltei to the local flow and to erosion and deposition rates were calibrated using flume experimental measurements; results from the calibration of the model are presented . . .
Date: 10/2014 Publisher: Ocean Dynamics Pages: 1499 - 1516 DOI: 10.1007/s10236-014-0754-1 Available at: http://link.springer.com/10.1007/s10236-014-0754-1http://link.springer.com/content/pdf/10.1007/s10236-014-0754-1
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Authors: Klein Kristopher G., and Chandran Benjamin D. G.
Title: EVOLUTION OF THE PROTON VELOCITY DISTRIBUTION DUE TO STOCHASTIC HEATING IN THE NEAR-SUN SOLAR WIND
Abstract:

We investigate how the proton distribution function evolves when the protons undergo stochastic heating by strong, low-frequency, Alfvén-wave turbulence under the assumption that β is small. We apply our analysis to protons undergoing stochastic heating in the supersonic fast solar wind and obtain proton distributions at heliocentric distances ranging from 4 to 30 solar radii. We find that the proton distribution develops non-Gaussian structure with a flat core and steep tail. For r\gt 5 R{S, the proton distribution is well approximated by a modified Moyal distribution. Comparisons with future measurements from Solar Probe Plus could be used to test whether stochastic heating is occurring in the solar-wind acceleration region.


Date: 03/2016 Publisher: The Astrophysical Journal Pages: 47 DOI: 10.3847/0004-637X/820/1/47 Available at: http://stacks.iop.org/0004-637X/820/i=1/a=47?key=crossref.3bba6a0e184137847bf77cde72a2fe1fhttp://stacks.iop.org/0004-637X/820/i=1/a=47/pdfhttp://stacks.iop.org/0004-637X/820/i=1/a=47?key=crossref.3bba6a0e184137847bf77cde72a2fe1f
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Authors: Klein Kristopher G., and Chandran Benjamin D. G.
Title: EVOLUTION OF THE PROTON VELOCITY DISTRIBUTION DUE TO STOCHASTIC HEATING IN THE NEAR-SUN SOLAR WIND
Abstract:

We investigate how the proton distribution function evolves when the protons undergo stochastic heating by strong, low-frequency, Alfvén-wave turbulence under the assumption that β is small. We apply our analysis to protons undergoing stochastic heating in the supersonic fast solar wind and obtain proton distributions at heliocentric distances ranging from 4 to 30 solar radii. We find that the proton distribution develops non-Gaussian structure with a flat core and steep tail. For r\gt 5 {R}{{S}}, the proton distribution is well approximated by a modified Moyal distribution. Comparisons with future measurements from Solar Probe Plus could be used to test whether stochastic heating is occurring in the solar-wind acceleration region.


Date: 03/2016 Publisher: The Astrophysical Journal Pages: 47 DOI: 10.3847/0004-637X/820/1/47 Available at: http://stacks.iop.org/0004-637X/820/i=1/a=47?key=crossref.3bba6a0e184137847bf77cde72a2fe1fhttp://stacks.iop.org/0004-637X/820/i=1/a=47/pdfhttp://stacks.iop.org/0004-637X/820/i=1/a=47?key=crossref.3bba6a0e184137847bf77cde72a2fe1f
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Authors: Klein K. G., and Howes G. G.
Title: MEASURING COLLISIONLESS DAMPING IN HELIOSPHERIC PLASMAS USING FIELD–PARTICLE CORRELATIONS
Abstract:

An innovative field-particle correlation technique is proposed that uses single-point measurements of the electromagnetic fields and particle velocity distribution functions to investigate the net transfer of energy from fields to particles associated with the collisionless damping of turbulent fluctuations in weakly collisional plasmas, such as the solar wind. In addition to providing a direct estimate of the local rate of energy transfer between fields and particles, it provides vital new information about the distribution of that energy transfer in velocity space. This velocity-space signature can potentially be used to identify the dominant collisionless mechanism responsible for the damping of turbulent fluctuations in the solar wind. The application of this novel field-particle co. . .
Date: 08/2016 Publisher: The Astrophysical Journal Pages: L30 DOI: 10.3847/2041-8205/826/2/L30 Available at: http://stacks.iop.org/2041-8205/826/i=2/a=L30?key=crossref.1f33350dac6f20e78faa0a9e9d852985http://stacks.iop.org/2041-8205/826/i=2/a=L30/pdfhttp://stacks.iop.org/2041-8205/826/i=2/a=L30?key=crossref.1f33350dac6f20e78faa0a9e9d852985
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Authors: Klein Kristopher G., Perez Jean C., Verscharen Daniel, Mallet Alfred, and Chandran Benjamin D. G.
Title: A MODIFIED VERSION OF TAYLOR’S HYPOTHESIS FOR SOLAR PROBE PLUS OBSERVATIONS
Abstract:

The Solar Probe Plus (SPP) spacecraft will explore the near-Sun environment, reaching heliocentric distances less than 10 {R. Near Earth, spacecraft measurements of fluctuating velocities and magnetic fields taken in the time domain are translated into information about the spatial structure of the solar wind via Taylor’s “frozen turbulence” hypothesis. Near the perihelion of SPP, however, the solar-wind speed is comparable to the Alfvén speed, and Taylor’s hypothesis in its usual form does not apply. In this paper, we show that under certain assumptions, a modified version of Taylor’s hypothesis can be recovered in the near-Sun region. We consider only the transverse, non-compressive component of the fluctuations at length scales exceeding the proton gyroradiu. . .
Date: 03/2015 Publisher: The Astrophysical Journal Pages: L18 DOI: 10.1088/2041-8205/801/1/L18 Available at: http://stacks.iop.org/2041-8205/801/i=1/a=L18?key=crossref.c92a2bde23ce9cdd58185dec581d5a09
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Authors: Klein Kristopher G., Perez Jean C., Verscharen Daniel, Mallet Alfred, and Chandran Benjamin D. G.
Title: A MODIFIED VERSION OF TAYLOR’S HYPOTHESIS FOR SOLAR PROBE PLUS OBSERVATIONS
Abstract:

The Solar Probe Plus (SPP) spacecraft will explore the near-Sun environment, reaching heliocentric distances less than 10 {{R}}. Near Earth, spacecraft measurements of fluctuating velocities and magnetic fields taken in the time domain are translated into information about the spatial structure of the solar wind via Taylor’s “frozen turbulence” hypothesis. Near the perihelion of SPP, however, the solar-wind speed is comparable to the Alfvén speed, and Taylor’s hypothesis in its usual form does not apply. In this paper, we show that under certain assumptions, a modified version of Taylor’s hypothesis can be recovered in the near-Sun region. We consider only the transverse, non-compressive component of the fluctuations at length scales exceeding the proton gyrora. . .
Date: 03/2015 Publisher: The Astrophysical Journal Pages: L18 DOI: 10.1088/2041-8205/801/1/L18 Available at: http://stacks.iop.org/2041-8205/801/i=1/a=L18?key=crossref.c92a2bde23ce9cdd58185dec581d5a09
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Authors: Klein K. G., Howes G. G., and TenBarge J. M.
Title: THE VIOLATION OF THE TAYLOR HYPOTHESIS IN MEASUREMENTS OF SOLAR WIND TURBULENCE
Abstract:

Motivated by the upcoming Solar Orbiter and Solar Probe Plus missions, qualitative and quantitative predictions are made for the effects of the violation of the Taylor hypothesis on the magnetic energy frequency spectrum measured in the near-Sun environment. The synthetic spacecraft data method is used to predict observational signatures of the violation for critically balanced Alfvénic turbulence or parallel fast/whistler turbulence. The violation of the Taylor hypothesis can occur in the slow flow regime, leading to a shift of the entire spectrum to higher frequencies, or in the dispersive regime, in which the dissipation range spectrum flattens at high frequencies. It is found that Alfvénic turbulence will not significantly violate the Taylor hypothesis, but whistler turbulence wil. . .
Date: 08/2014 Publisher: The Astrophysical Journal Pages: L20 DOI: 10.1088/2041-8205/790/2/L20 Available at: http://stacks.iop.org/2041-8205/790/i=2/a=L20?key=crossref.9873bcfbec22617b78b4a7d0cb1dbb95
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Authors: Klein K. G., and Howes G. G.
Title: MEASURING COLLISIONLESS DAMPING IN HELIOSPHERIC PLASMAS USING FIELD–PARTICLE CORRELATIONS
Abstract:

An innovative field-particle correlation technique is proposed that uses single-point measurements of the electromagnetic fields and particle velocity distribution functions to investigate the net transfer of energy from fields to particles associated with the collisionless damping of turbulent fluctuations in weakly collisional plasmas, such as the solar wind. In addition to providing a direct estimate of the local rate of energy transfer between fields and particles, it provides vital new information about the distribution of that energy transfer in velocity space. This velocity-space signature can potentially be used to identify the dominant collisionless mechanism responsible for the damping of turbulent fluctuations in the solar wind. The application of this novel field-particle co. . .
Date: 08/2016 Publisher: The Astrophysical Journal Pages: L30 DOI: 10.3847/2041-8205/826/2/L30 Available at: http://stacks.iop.org/2041-8205/826/i=2/a=L30?key=crossref.1f33350dac6f20e78faa0a9e9d852985http://stacks.iop.org/2041-8205/826/i=2/a=L30/pdfhttp://stacks.iop.org/2041-8205/826/i=2/a=L30?key=crossref.1f33350dac6f20e78faa0a9e9d852985
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Authors: Klein K. G., Howes G. G., and TenBarge J. M.
Title: THE VIOLATION OF THE TAYLOR HYPOTHESIS IN MEASUREMENTS OF SOLAR WIND TURBULENCE
Abstract:

Motivated by the upcoming Solar Orbiter and Solar Probe Plus missions, qualitative and quantitative predictions are made for the effects of the violation of the Taylor hypothesis on the magnetic energy frequency spectrum measured in the near-Sun environment. The synthetic spacecraft data method is used to predict observational signatures of the violation for critically balanced Alfvénic turbulence or parallel fast/whistler turbulence. The violation of the Taylor hypothesis can occur in the slow flow regime, leading to a shift of the entire spectrum to higher frequencies, or in the dispersive regime, in which the dissipation range spectrum flattens at high frequencies. It is found that Alfvénic turbulence will not significantly violate the Taylor hypothesis, but whistler turbulence wil. . .
Date: 08/2014 Publisher: The Astrophysical Journal Pages: L20 DOI: 10.1088/2041-8205/790/2/L20 Available at: http://stacks.iop.org/2041-8205/790/i=2/a=L20?key=crossref.9873bcfbec22617b78b4a7d0cb1dbb95
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Authors: Kim T. K., Pogorelov N. V., Arge C. N., Henney C. J., Jones-Mecholsky S. I., et al.
Title: Predicting the Solar Wind at the Parker Solar Probe Using an Empirically Driven MHD Model
Abstract:

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 its launch to the completion of the second orbit, with particular emphasis on the solar wind structure around the first two solar encounters. Furthermore, we show our model prediction for the third perihelion, which occurred on 2019 September 1. Comparison of the MHD r. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 40 DOI: 10.3847/1538-4365/ab58c9 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab58c9
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Authors: Kim T. K., Pogorelov N. V., Arge C. N., Henney C. J., Jones-Mecholsky S. I., et al.
Title: Predicting the Solar Wind at the Parker Solar Probe Using an Empirically Driven MHD Model
Abstract:

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 its launch to the completion of the second orbit, with particular emphasis on the solar wind structure around the first two solar encounters. Furthermore, we show our model prediction for the third perihelion, which occurred on 2019 September 1. Comparison of the MHD r. . .
Date: 02/2020 Publisher: The Astrophysical Journal Supplement Series Pages: 40 DOI: 10.3847/1538-4365/ab58c9 Available at: https://iopscience.iop.org/article/10.3847/1538-4365/ab58c9
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