158 citations · 1.5k across the 55 of their papers we have counts for
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Spherically Polarized Alfvén Waves and the Gosling Boost
Yuliang Ding, Marco Velli, Zesen Huang +6
Alfvén waves are thought to play critical roles in solar wind acceleration and plasma heating in the solar corona and inner heliosphere. Parker Solar Probe (PSP) has highlighted th…
On the Propagation and Damping of Alfvenic Fluctuations in the Outer Solar Corona and Solar Wind
Nikos Sioulas, Marco Velli, Chen Shi +17
We analyze \textit{Parker Solar Probe} and \textit{Solar Orbiter} observations to investigate the propagation and dissipation of Alfvénic fluctuations from the outer corona to 1~AU…
Evolution of MHD turbulence in the expanding solar wind: residual energy and intermittency
Chen Shi, Nikos Sioulas, Zesen Huang +3
We conduct 3D magnetohydrodynamic (MHD) simulations of decaying turbulence in the solar wind context. To account for the spherical expansion of the solar wind, we implement the exp…
Dispersive and kinetic effects on kinked Alfvén wave packets: a comparative study with fluid and hybrid models
Anna Tenerani, Carlos González, Nikos Sioulas +2
We investigate dispersive and kinetic effects on the evolution of a two-dimensional kinked Alfvén wave packet by comparing results from MHD, Hall-MHD and hybrid simulations of a lo…
Proton and electron temperatures in the solar wind and their correlations with the solar wind speed
Chen Shi, Marco Velli, Roberto Lionello +8
The heating and acceleration of the solar wind remains one of the fundamental unsolved problems in heliophysics. It is usually observed that the proton temperature is highly…
Parker Solar Probe: Four Years of Discoveries at Solar Cycle Minimum
N. E. Raouafi, L. Matteini, J. Squire +54
Launched on 12 Aug. 2018, NASA's Parker Solar Probe had completed 13 of its scheduled 24 orbits around the Sun by Nov. 2022. The mission's primary science goal is to determine the…
Magnetic field spectral evolution in the inner heliosphere
Nikos Sioulas, Zesen Huang, Chen Shi +23
Parker Solar Probe and Solar Orbiter data are used to investigate the radial evolution of magnetic turbulence between au. The spectrum is studied as…
Patches of magnetic switchbacks and their origins
Chen Shi, Olga Panasenco, Marco Velli +18
Parker Solar Probe (PSP) has shown that the solar wind in the inner heliosphere is characterized by the quasi omni-presence of magnetic switchbacks ("switchback" hereinafter), loca…
Influence of the heliospheric current sheet on the evolution of solar wind turbulence
Chen Shi, Marco Velli, Anna Tenerani +2
The effects of the heliospheric current sheet (HCS) on the evolution of Alfvénic turbulence in the solar wind are studied using MHD simulations incorporating the expanding-box-mode…
Evolution of switchbacks in the inner Heliosphere
Anna Tenerani, Nikos Sioulas, Lorenzo Matteini +3
We analyze magnetic field data from the first six encounters of PSP, three Helios fast streams and two Ulysses south polar passes covering heliocentric distances $0.1\lesssim R\les…
On the role of solar wind expansion as a source of whistler waves: scattering of suprathermal electrons and heat flux regulation in the inner heliosphere
A. Micera, A. N. Zhukov, R. A. López +5
The role of solar wind expansion in generating whistler waves is investigated using the EB-iPic3D code, which models solar wind expansion self-consistently within a fully kinetic s…
Alfvénic versus non-Alfvénic turbulence in the inner heliosphere as observed by Parker Solar Probe
Chen Shi, Marco Velli, Olga Panasenco +20
We make use of the Parker Solar Probe (PSP) data to explore the nature of solar wind turbulence focusing on the Alfvénic character and power spectra of the fluctuations and their d…
Tearing modes in partially ionized plasmas
Fulvia Pucci, K. Alkendra P. Singh, Anna Tenerani +1
In many astrophysical environments the plasma is only partially ionized, and therefore the interaction of charged and neutral particles may alter both the triggering of reconnectio…
Tearing instability and periodic density perturbations in the slow solar wind
Victor Réville, Marco Velli, Alexis Rouillard +4
In contrast with the fast solar wind, that originates in coronal holes, the source of the slow solar wind is still debated. Often intermittent and enriched with low FIP elements --…
The role of Alfvén wave dynamics on the large scale properties of the solar wind: comparing an MHD simulation with PSP E1 data
Victor Réville, Marco Velli, Olga Panasenco +18
During Parker Solar Probe's first orbit, the solar wind plasma has been observed in situ closer than ever before, the perihelion on November 6th 2018 revealing a flow that is const…
Propagation of Alfvén waves in the expanding solar wind with the fast-slow stream interaction
Chen Shi, Marco Velli, Anna Tenerani +2
We carry out two-dimensional magnetohydrodynamic (MHD) simulations of an ensemble of Alfvénic fluctuations propagating in a structured, expanding solar wind including the presence…
Fast Recursive Reconnection and the Hall effect: Hall-MHD Simulations
Chen Shi, Anna Tenerani, Marco Velli +1
Magnetohydrodynamic (MHD) theory and simulations have shown that reconnection is triggered via a fast "ideal" tearing instability in current sheets whose inverse aspect ratio decre…
Parametric decay and the origin of the low frequency Alfvénic spectrum of the solar wind
Réville Victor, Tenerani Anna, Velli Marco
The fast solar wind shows a wide spectrum of transverse magnetic and velocity field perturbations. These perturbations are strongly correlated in the sense of Alfvén waves propagat…
Fast Magnetic Reconnection: "Ideal" Tearing and the Hall Effect
Fulvia Pucci, Marco Velli, Anna Tenerani
One of the main questions in magnetic reconnection is the origin of triggering behavior with on/off properties that accounts, once it is activated, for the fast magnetic energy con…
Evolving waves and turbulence in the outer corona and inner heliosphere: the accelerating expanding box
Anna Tenerani, Marco Velli
Alfvénic fluctuations in the solar wind display many properties reflecting an ongoing nonlinear cascade, e.g. a well-defined spectrum in frequency, together with some characteristi…
"Ideally" unstable current sheets and the triggering of fast magnetic reconnection
Anna Tenerani, Marco Velli, Fulvia Pucci +2
Magnetic reconnection is thought to be the dynamical mechanism underlying many explosive phenomena observed both in space and in the laboratory, though the question of how fast mag…