Transonic Turbulence and Density Fluctuations in the Near-Sun Solar Wind

Zhao, L.-L.; Silwal, A.; Zhu, X.; Li, H.; Zank, G. P.

doi:10.3847/2041-8213/ada3d8

Transonic Turbulence and Density Fluctuations in the Near-Sun Solar Wind

Journal Article · Mon Jan 13 00:00:00 EST 2025 · The Astrophysical Journal. Letters

DOI:https://doi.org/10.3847/2041-8213/ada3d8· OSTI ID:2570797

^[1]; ^[1]; ^[1]; ^[2]; ^[1]

Univ. of Alabama, Huntsville, AL (United States)
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

We use in situ measurements from the first 19 encounters of Parker Solar Probe and the most recent five encounters of Solar Orbiter to study the evolution of the turbulent sonic Mach number M_t (the ratio of the amplitude of velocity fluctuations to the sound speed) with radial distance and its relationship to density fluctuations. We focus on the near-Sun region with radial distances ranging from about 11 to 80 R_⊙. Our results show that (1) the turbulent sonic Mach number M_t gradually moves toward larger values as it approaches the Sun, until at least 11 R_⊙, where M_t is much larger than the previously observed value of 0.1 at and above 0.3 au; (2) transonic turbulence with M_t ∼ 1 is observed in situ for the first time and is found mostly near the Alfvén critical surface; (3) Alfvén Mach number of the bulk flow M_A shows a strong correlation with the plasma beta, indicating that most of the observed sub-Alfvénic intervals correspond to a low-beta plasma; (4) the scaling relation between density fluctuations and M_t gradually changes from a linear scaling at larger radial distances to a quadratic scaling at smaller radial distances; and (5) transonic turbulence is more compressible than subsonic turbulence, with enhanced density fluctuations and slightly flatter spectra than subsonic turbulence. A systematic understanding of compressible turbulence near the Sun is necessary for future solar wind modeling efforts.

View Accepted Manuscript (DOE)

Research Organization:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Organization:: National Aeronautics and Space Administration (NASA); USDOE National Nuclear Security Administration (NNSA)

Grant/Contract Number:: 89233218CNA000001

OSTI ID:: 2570797

Report Number(s):: LA-UR--25-20000; 10.3847/2041-8213/ada3d8; 2041-8213

Journal Information:: The Astrophysical Journal. Letters, Journal Name: The Astrophysical Journal. Letters Journal Issue: 1 Vol. 979; ISSN 2041-8205; ISSN 2041-8213

Publisher:: IOP PublishingCopyright Statement

Country of Publication:: United States

Language:: English

References (85)

MHD structures, waves and turbulence in the solar wind: Observations and theories Tu, C. -Y.; Marsch, E. Space Science Reviews, Vol. 73, Issue 1-2 https://doi.org/10.1007/BF00748891	journal	July 1995
Solar Wind Electrons Alphas and Protons (SWEAP) Investigation: Design of the Solar Wind and Coronal Plasma Instrument Suite for Solar Probe Plus Kasper, Justin C.; Abiad, Robert; Austin, Gerry Space Science Reviews, Vol. 204, Issue 1-4 https://doi.org/10.1007/s11214-015-0206-3	journal	October 2015
The FIELDS Instrument Suite for Solar Probe Plus: Measuring the Coronal Plasma and Magnetic Field, Plasma Waves and Turbulence, and Radio Signatures of Solar Transients Bale, S. D.; Goetz, K.; Harvey, P. R. Space Science Reviews, Vol. 204, Issue 1-4 https://doi.org/10.1007/s11214-016-0244-5	journal	March 2016
Origins of the Ambient Solar Wind: Implications for Space Weather Cranmer, Steven R.; Gibson, Sarah E.; Riley, Pete Space Science Reviews, Vol. 212, Issue 3-4 https://doi.org/10.1007/s11214-017-0416-y	journal	October 2017
Spectrum and energy transfer in steady Burgers turbulence Girimaji, Sharath S.; Zhou, Ye Physics Letters A, Vol. 202, Issue 4 https://doi.org/10.1016/0375-9601(95)00317-V	journal	June 1995
Particle-in-cell simulations of Alfvén wave parametric decay in a low-beta plasma González, C. A.; Innocenti, Maria Elena; Tenerani, Anna Journal of Plasma Physics, Vol. 89, Issue 2 https://doi.org/10.1017/S0022377823000120	journal	April 2023
Fast and Slow Flows in the Solar Wind Near the Ecliptic at 1 AU? Burlaga, L. F.; Szabo, A. Space Science Reviews, Vol. 87, Issue 1-2 https://doi.org/10.1023/A:1005186720589	journal	January 1999
Formation of pressure-balanced structures and fast waves from nonlinear Alfvén waves Vasquez, Bernard J.; Hollweg, Joseph V. Journal of Geophysical Research: Space Physics, Vol. 104, Issue A3 https://doi.org/10.1029/1998JA900090	journal	March 1999
Interplanetary magnetic fluctuation anisotropy in the inertial range Smith, Charles W.; Vasquez, Bernard J.; Hamilton, Kathleen Journal of Geophysical Research, Vol. 111, Issue A9 https://doi.org/10.1029/2006JA011651	journal	January 2006
Correlation and Taylor scale variability in the interplanetary magnetic field fluctuations as a function of solar wind speed Weygand, James M.; Matthaeus, W. H.; Dasso, S. Journal of Geophysical Research: Space Physics, Vol. 116, Issue A8 https://doi.org/10.1029/2011JA016621	journal	August 2011
Nearly incompressible magnetohydrodynamics, pseudosound, and solar wind fluctuations Matthaeus, William H.; Klein, Larry W.; Ghosh, Sanjoy Journal of Geophysical Research, Vol. 96, Issue A4 https://doi.org/10.1029/90JA02609	journal	January 1991
Waves and turbulence in the solar wind Zank, G. P.; Matthaeus, W. H. Journal of Geophysical Research, Vol. 97, Issue A11 https://doi.org/10.1029/92JA01734	journal	January 1992
Scaling of density fluctuations with Mach number and density-temperature anticorrelations in the inner heliosphere Klein, L.; Bruno, R.; Bavassano, B. Journal of Geophysical Research: Space Physics, Vol. 98, Issue A5 https://doi.org/10.1029/92JA02906	journal	May 1993
On the nature of compressive fluctuations in the solar wind Tu, C. -Y.; Marsch, E. Journal of Geophysical Research, Vol. 99, Issue A11 https://doi.org/10.1029/94JA00843	journal	January 1994
Density fluctuations and turbulent Mach numbers in the inner solar wind Bavassano, B.; Bruno, R. Journal of Geophysical Research: Space Physics, Vol. 100, Issue A6 https://doi.org/10.1029/94JA03048	journal	June 1995
Temperature and density anti‐correlations in solar wind fluctuations Zank, G. P.; Matthaeus, W. H.; Klein, L. W. Geophysical Research Letters, Vol. 17, Issue 9 https://doi.org/10.1029/GL017i009p01239	journal	August 1990
Large-amplitude Alfvén waves in the interplanetary medium, 2 Belcher, J. W.; Davis, Leverett Journal of Geophysical Research, Vol. 76, Issue 16 https://doi.org/10.1029/JA076i016p03534	journal	June 1971
Supersonic plasma turbulence in the laboratory White, T. G.; Oliver, M. T.; Mabey, P. Nature Communications, Vol. 10, Issue 1 https://doi.org/10.1038/s41467-019-09498-y	journal	April 2019
Highly structured slow solar wind emerging from an equatorial coronal hole Bale, S. D.; Badman, S. T.; Bonnell, J. W. Nature, Vol. 576, Issue 7786 https://doi.org/10.1038/s41586-019-1818-7	journal	December 2019
Compressible magnetohydrodynamic turbulence: mode coupling, scaling relations, anisotropy, viscosity-damped regime and astrophysical implications Cho, Jungyeon; Lazarian, A. Monthly Notices of the Royal Astronomical Society, Vol. 345, Issue 1 https://doi.org/10.1046/j.1365-8711.2003.06941.x	journal	October 2003
The Solar Orbiter Radio and Plasma Waves (RPW) instrument Maksimovic, M.; Bale, S. D.; Chust, T. Astronomy & Astrophysics, Vol. 642 https://doi.org/10.1051/0004-6361/201936214	journal	September 2020
The Solar Orbiter magnetometer Horbury, T. S.; O’Brien, H.; Carrasco Blazquez, I. Astronomy & Astrophysics, Vol. 642 https://doi.org/10.1051/0004-6361/201937257	journal	September 2020
The Solar Orbiter Solar Wind Analyser (SWA) suite Owen, C. J.; Bruno, R.; Livi, S. Astronomy & Astrophysics, Vol. 642 https://doi.org/10.1051/0004-6361/201937259	journal	September 2020
Detection of small magnetic flux ropes from the third and fourth Parker Solar Probe encounters Zhao, L. -L.; Zank, G. P.; Hu, Q. Astronomy & Astrophysics, Vol. 650 https://doi.org/10.1051/0004-6361/202039298	journal	June 2021
Turbulence and wave transmission at an ICME-driven shock observed by the Solar Orbiter and Wind Zhao, L. -L.; Zank, G. P.; He, J. S. Astronomy & Astrophysics, Vol. 656 https://doi.org/10.1051/0004-6361/202140450	journal	December 2021
Evolution of anisotropic turbulence in the fast and slow solar wind: Theory and Solar Orbiter measurements Adhikari, L.; Zank, G. P.; Zhao, L. -L. Astronomy & Astrophysics https://doi.org/10.1051/0004-6361/202140672	journal	April 2021
Density fluctuations associated with turbulence and waves Khotyaintsev, Yu. V.; Graham, D. B.; Vaivads, A. Astronomy & Astrophysics, Vol. 656 https://doi.org/10.1051/0004-6361/202140936	journal	December 2021
Parker Solar Probe observations of collisional effects on thermalizing the young solar wind Mostafavi, P.; Allen, R. C.; Jagarlamudi, V. K. Astronomy & Astrophysics, Vol. 682 https://doi.org/10.1051/0004-6361/202347134	journal	February 2024
Parametric decay of circularly polarized Alfvén waves: Multidimensional simulations in periodic and open domains Del Zanna, L.; Velli, M.; Londrillo, P. Astronomy & Astrophysics, Vol. 367, Issue 2 https://doi.org/10.1051/0004-6361:20000455	journal	February 2001
Nearly incompressible fluids. II: Magnetohydrodynamics, turbulence, and waves Zank, G. P.; Matthaeus, W. H. Physics of Fluids A: Fluid Dynamics, Vol. 5, Issue 1 https://doi.org/10.1063/1.858780	journal	January 1993
Parametric instability of a large‐amplitude nonmonochromatic Alfvén wave Malara, F.; Velli, M. Physics of Plasmas, Vol. 3, Issue 12 https://doi.org/10.1063/1.872043	journal	December 1996
Turbulence, Viscosity, and Dissipation in the Solar-Wind Plasma Coleman, Paul J. , Jr. The Astrophysical Journal, Vol. 153 https://doi.org/10.1086/149674	journal	August 1968
Toward a theory of interstellar turbulence. 2: Strong alfvenic turbulence Goldreich, P.; Sridhar, S. The Astrophysical Journal, Vol. 438 https://doi.org/10.1086/175121	journal	January 1995
Weakly Compressible Magnetohydrodynamic Turbulence in the Solar Wind and the Interstellar Medium Bhattacharjee, A.; Ng, C. S.; Spangler, S. R. The Astrophysical Journal, Vol. 494, Issue 1 https://doi.org/10.1086/305184	journal	February 1998
Anisotropy in Fast and Slow Solar Wind Fluctuations Dasso, S.; Milano, L. J.; Matthaeus, W. H. The Astrophysical Journal, Vol. 635, Issue 2 https://doi.org/10.1086/499559	journal	December 2005
Alfven Waves and Turbulence in the Solar Atmosphere and Solar Wind Verdini, Andrea; Velli, Marco The Astrophysical Journal, Vol. 662, Issue 1 https://doi.org/10.1086/510710	journal	June 2007
Inhomogeneous Nearly Incompressible Description of Magnetohydrodynamic Turbulence Hunana, P.; Zank, G. P. The Astrophysical Journal, Vol. 718, Issue 1 https://doi.org/10.1088/0004-637X/718/1/148	journal	June 2010
The Slow-Mode Nature of Compressible wave Power in Solar wind Turbulence Howes, G. G.; Bale, S. D.; Klein, K. G. The Astrophysical Journal, Vol. 753, Issue 1 https://doi.org/10.1088/2041-8205/753/1/L19	journal	June 2012
The Alfvén transition zone observed by the Parker Solar Probe in young solar wind – global properties and model comparisons Chhiber, Rohit; Pecora, Francesco; Usmanov, Arcadi V. Monthly Notices of the Royal Astronomical Society: Letters, Vol. 533, Issue 1 https://doi.org/10.1093/mnrasl/slae051	journal	June 2024
Parker Solar Probe Enters the Magnetically Dominated Solar Corona Kasper, J. C.; Klein, K. G.; Lichko, E. Physical Review Letters, Vol. 127, Issue 25 https://doi.org/10.1103/PhysRevLett.127.255101	journal	December 2021
Nearly incompressible hydrodynamics and heat conduction Zank, G. P.; Matthaeus, W. H. Physical Review Letters, Vol. 64, Issue 11 https://doi.org/10.1103/PhysRevLett.64.1243	journal	March 1990
Compressible Sub-Alfvénic MHD Turbulence in Low- β Plasmas Cho, Jungyeon; Lazarian, A. Physical Review Letters, Vol. 88, Issue 24 https://doi.org/10.1103/PhysRevLett.88.245001	journal	May 2002
Ion versus Electron Heating in Compressively Driven Astrophysical Gyrokinetic Turbulence Kawazura, Y.; Schekochihin, A. A.; Barnes, M. Physical Review X, Vol. 10, Issue 4 https://doi.org/10.1103/PhysRevX.10.041050	journal	December 2020
Turbulence spectra generated by singularities Kuznetsov, E. A. Journal of Experimental and Theoretical Physics Letters, Vol. 80, Issue 2 https://doi.org/10.1134/1.1804214	journal	July 2004
The Solar Wind as a Turbulence Laboratory Bruno, Roberto; Carbone, Vincenzo Living Reviews in Solar Physics, Vol. 10 https://doi.org/10.12942/lrsp-2013-2	journal	January 2013
Theory and Transport of Nearly Incompressible Magnetohydrodynamic Turbulence Zank, G. P.; Adhikari, L.; Hunana, P. The Astrophysical Journal, Vol. 835, Issue 2 https://doi.org/10.3847/1538-4357/835/2/147	journal	January 2017
On Kinetic Slow Modes, Fluid Slow Modes, and Pressure-balanced Structures in the Solar Wind Verscharen, Daniel; Chen, Christopher H. K.; Wicks, Robert T. The Astrophysical Journal, Vol. 840, Issue 2 https://doi.org/10.3847/1538-4357/aa6a56	journal	May 2017
The Parametric Decay Instability of Alfvén Waves in Turbulent Plasmas and the Applications in the Solar Wind Shi, Mijie; Li, Hui; Xiao, Chijie The Astrophysical Journal, Vol. 842, Issue 1 https://doi.org/10.3847/1538-4357/aa71b6	journal	June 2017
Cosmic Ray Diffusion Tensor throughout the Heliosphere Derived from a Nearly Incompressible Magnetohydrodynamic Turbulence Model Zhao, L. -L.; Adhikari, L.; Zank, G. P. The Astrophysical Journal, Vol. 849, Issue 2 https://doi.org/10.3847/1538-4357/aa932a	journal	November 2017
Parametric Decay Instability and Dissipation of Low-frequency Alfvén Waves in Low-beta Turbulent Plasmas Fu, Xiangrong; Li, Hui; Guo, Fan The Astrophysical Journal, Vol. 855, Issue 2 https://doi.org/10.3847/1538-4357/aaacd6	journal	March 2018
The Steady Global Corona and Solar Wind: A Three-dimensional MHD Simulation with Turbulence Transport and Heating Usmanov, Arcadi V.; Matthaeus, William H.; Goldstein, Melvyn L. The Astrophysical Journal, Vol. 865, Issue 1 https://doi.org/10.3847/1538-4357/aad687	journal	September 2018
Solar Wind Turbulence Studies Using MMS Fast Plasma Investigation Data Bandyopadhyay, Riddhi; Chasapis, A.; Chhiber, R. The Astrophysical Journal, Vol. 866, Issue 2 https://doi.org/10.3847/1538-4357/aade93	journal	October 2018
Magnetic and Velocity Fluctuations in the Near-Sun Region from 0.1−0.3 au Observed by Parker Solar Probe Wu, Honghong; Tu, Chuanyi; Wang, Xin The Astrophysical Journal, Vol. 922, Issue 2 https://doi.org/10.3847/1538-4357/ac3331	journal	November 2021
Nature and Scalings of Density Fluctuations of Compressible Magnetohydrodynamic Turbulence with Applications to the Solar Wind Fu, Xiangrong; Li, Hui; Gan, Zhaoming The Astrophysical Journal, Vol. 936, Issue 2 https://doi.org/10.3847/1538-4357/ac8802	journal	September 2022
The Solar Probe ANalyzer—Ions on the Parker Solar Probe Livi, Roberto; Larson, Davin E.; Kasper, Justin C. The Astrophysical Journal, Vol. 938, Issue 2 https://doi.org/10.3847/1538-4357/ac93f5	journal	October 2022
Statistical Analysis of the Radial Evolution of the Solar Winds between 0.1 and 1 au and Their Semiempirical Isopoly Fluid Modeling Dakeyo, Jean-Baptiste; Maksimovic, Milan; Démoulin, Pascal The Astrophysical Journal, Vol. 940, Issue 2 https://doi.org/10.3847/1538-4357/ac9b14	journal	November 2022
Anisotropic Energy Transfer and Conversion in Magnetized Compressible Turbulence Du, Senbei; Li, Hui; Fu, Xiangrong The Astrophysical Journal, Vol. 948, Issue 2 https://doi.org/10.3847/1538-4357/acc5e9	journal	May 2023
Turbulence, and Proton and Electron Heating Rates in the Solar Corona: Analytical Approach Adhikari, Laxman; Zank, Gary P.; Telloni, Daniele The Astrophysical Journal, Vol. 966, Issue 1 https://doi.org/10.3847/1538-4357/ad3109	journal	April 2024
A Survey of Coronal Mass Ejections Measured In Situ by Parker Solar Probe during 2018–2022 Salman, Tarik Mohammad; Nieves-Chinchilla, Teresa; Jian, Lan K. The Astrophysical Journal, Vol. 966, Issue 1 https://doi.org/10.3847/1538-4357/ad320c	journal	April 2024
Characterization of Turbulent Fluctuations in the Sub-Alfvénic Solar Wind Zank, G. P.; Zhao, L. -L.; Adhikari, L. The Astrophysical Journal, Vol. 966, Issue 1 https://doi.org/10.3847/1538-4357/ad34ab	journal	April 2024
Exact Nonlinear Decomposition of Ideal-MHD Waves Using Eigenenergies Raboonik, Axel; Tarr, Lucas A.; Pontin, David I. The Astrophysical Journal, Vol. 967, Issue 2 https://doi.org/10.3847/1538-4357/ad3bb6	journal	May 2024
Anisotropy of Density Fluctuations in the Solar Wind at 1 au Wang, Jiaming; Chhiber, Rohit; Roy, Sohom The Astrophysical Journal, Vol. 967, Issue 2 https://doi.org/10.3847/1538-4357/ad3e7a	journal	May 2024
Near Subsonic Solar Wind Outflow from an Active Region Ervin, Tamar; Bale, Stuart D.; Badman, Samuel T. The Astrophysical Journal, Vol. 972, Issue 1 https://doi.org/10.3847/1538-4357/ad57c4	journal	August 2024
Turbulence, Waves, and Taylor’s Hypothesis for Heliosheath Observations Zhao, L. -L.; Zank, G. P.; Opher, M. The Astrophysical Journal, Vol. 973, Issue 1 https://doi.org/10.3847/1538-4357/ad64c8	journal	September 2024
Turbulence Transport Modeling and First Orbit Parker Solar Probe (PSP) Observations Adhikari, L.; Zank, G. P.; Zhao, L. -L. The Astrophysical Journal Supplement Series, Vol. 246, Issue 2 https://doi.org/10.3847/1538-4365/ab5852	journal	February 2020
The Solar Probe Cup on the Parker Solar Probe Case, A. W.; Kasper, Justin C.; Stevens, Michael L. The Astrophysical Journal Supplement Series, Vol. 246, Issue 2 https://doi.org/10.3847/1538-4365/ab5a7b	journal	February 2020
First In Situ Measurements of Electron Density and Temperature from Quasi-thermal Noise Spectroscopy with Parker Solar Probe/FIELDS Moncuquet, Michel; Meyer-Vernet, Nicole; Issautier, Karine The Astrophysical Journal Supplement Series, Vol. 246, Issue 2 https://doi.org/10.3847/1538-4365/ab5a84	journal	February 2020
The Heliospheric Current Sheet in the Inner Heliosphere Observed by the Parker Solar Probe Szabo, Adam; Larson, Davin; Whittlesey, Phyllis The Astrophysical Journal Supplement Series, Vol. 246, Issue 2 https://doi.org/10.3847/1538-4365/ab5dac	journal	February 2020
The Evolution and Role of Solar Wind Turbulence in the Inner Heliosphere Chen, C. H. K.; Bale, S. D.; Bonnell, J. W. The Astrophysical Journal Supplement Series, Vol. 246, Issue 2 https://doi.org/10.3847/1538-4365/ab60a3	journal	February 2020
Density Fluctuations in the Solar Wind Based on Type III Radio Bursts Observed by Parker Solar Probe Krupar, Vratislav; Szabo, Adam; Maksimovic, Milan The Astrophysical Journal Supplement Series, Vol. 246, Issue 2 https://doi.org/10.3847/1538-4365/ab65bd	journal	February 2020
Parker Solar Probe Observations of High Plasma β Solar Wind from the Streamer Belt Huang, Jia; Kasper, J. C.; Larson, Davin E. The Astrophysical Journal Supplement Series, Vol. 265, Issue 2 https://doi.org/10.3847/1538-4365/acbcd2	journal	March 2023
Linear Mode Decomposition in Magnetohydrodynamics Revisited Zank, G. P.; Zhao, L. -L.; Adhikari, L. The Astrophysical Journal Supplement Series, Vol. 268, Issue 1 https://doi.org/10.3847/1538-4365/acdf5d	journal	August 2023
Density Fluctuations in the Solar Wind Driven by Alfvén Wave Parametric Decay Bowen, Trevor A.; Badman, Samuel; Hellinger, Petr The Astrophysical Journal, Vol. 854, Issue 2 https://doi.org/10.3847/2041-8213/aaabbe	journal	February 2018
Evolution of Solar Wind Turbulence from 0.1 to 1 au during the First Parker Solar Probe–Solar Orbiter Radial Alignment Telloni, Daniele; Sorriso-Valvo, Luca; Woodham, Lloyd D. The Astrophysical Journal Letters, Vol. 912, Issue 2 https://doi.org/10.3847/2041-8213/abf7d1	journal	May 2021
Inertial-range Magnetic-fluctuation Anisotropy Observed from Parker Solar Probe’s First Seven Orbits Zhao, L. -L.; Zank, G. P.; Adhikari, L. The Astrophysical Journal Letters, Vol. 924, Issue 1 https://doi.org/10.3847/2041-8213/ac4415	journal	January 2022
Sub-Alfvénic Solar Wind Observed by the Parker Solar Probe: Characterization of Turbulence, Anisotropy, Intermittency, and Switchback Bandyopadhyay, R.; Matthaeus, W. H.; McComas, D. J. The Astrophysical Journal Letters, Vol. 926, Issue 1 https://doi.org/10.3847/2041-8213/ac4a5c	journal	February 2022
Turbulence in the Sub-Alfvénic Solar Wind Zank, G. P.; Zhao, L. -L.; Adhikari, L. The Astrophysical Journal Letters, Vol. 926, Issue 2 https://doi.org/10.3847/2041-8213/ac51da	journal	February 2022
The Turbulent Properties of the Sub-Alfvénic Solar Wind Measured by the Parker Solar Probe Zhao, L. -L.; Zank, G. P.; Telloni, D. The Astrophysical Journal Letters, Vol. 928, Issue 2 https://doi.org/10.3847/2041-8213/ac5fb0	journal	March 2022
Turbulence and Waves in the Sub-Alfvénic Solar Wind Observed by the Parker Solar Probe during Encounter 10 Zhao, L. -L.; Zank, G. P.; Adhikari, L. The Astrophysical Journal Letters, Vol. 934, Issue 2 https://doi.org/10.3847/2041-8213/ac8353	journal	August 2022
Modeling of Joint Parker Solar Probe–Metis/Solar Orbiter Observations Adhikari, L.; Zank, G. P.; Telloni, D. The Astrophysical Journal Letters, Vol. 937, Issue 2 https://doi.org/10.3847/2041-8213/ac91c6	journal	September 2022
Observation and Modeling of the Solar Wind Turbulence Evolution in the Sub-Mercury Inner Heliosphere Telloni, Daniele; Adhikari, Laxman; Zank, Gary P. The Astrophysical Journal Letters, Vol. 938, Issue 2 https://doi.org/10.3847/2041-8213/ac9624	journal	October 2022
Compressible Turbulence in the Near-Sun Solar Wind: Parker Solar Probe’s First Eight Perihelia Cuesta, Manuel Enrique; Chhiber, Rohit; Fu, Xiangrong The Astrophysical Journal Letters, Vol. 949, Issue 2 https://doi.org/10.3847/2041-8213/acd4c2	journal	May 2023
Effects of Nonzero-frequency Fluctuations on Turbulence Spectral Observations Zhao, L. -L.; Zank, G. P.; Li, H. The Astrophysical Journal Letters, Vol. 962, Issue 1 https://doi.org/10.3847/2041-8213/ad20e1	journal	February 2024
On the Acceleration of the Young Solar Wind from Different Source Regions Jiao, Yiming; Liu, Ying D.; Cheng, Wenshuai The Astrophysical Journal Letters, Vol. 975, Issue 2 https://doi.org/10.3847/2041-8213/ad85ea	journal	November 2024
Observed Fluctuation Enhancement and Departure from WKB Theory in Sub-Alfvénic Solar Wind Ruffolo, David; Thepthong, Panisara; Pongkitiwanichakul, Peera The Astrophysical Journal Letters, Vol. 977, Issue 1 https://doi.org/10.3847/2041-8213/ad9727	journal	December 2024