Turbulence is an ubiquitous phenomenon that can be observed on a huge range of scales, from galaxy clusters down to micro- and nano-fluidics. It is observed mostly in neutral flows, but also in charged, magnetized flows such as astrophysical plasmas. The study of turbulence requires a multiple approach: theoretical, experimental, based on data analysis and on numerical simulations. All these aspects are exploited here, with particular focus on space and laboratory turbulent plasmas.
Most of the visible matter in the universe is in the state of plasma. Often times, astrophysical plasmas have highly turbulent dynamics, resulting in a large number of interesting processes such as: energy dissipation, particle acceleration, excitation of electromagnetic waves, particle heating, magnetic reconnection, formation of shocks. All these phenomena can be studied in-situ only in space plasma, where instruments on-board scientific space missions can take measurements. Data can be studied using specific diagnostic tools, which allow the validation of theories and models. A substantial use of numerical simulations is also necessary. The study of turbulence in the interplanetary space is therefore of broad interest for the understanding of the dynamics of astrophysical plasmas, but also for its implications on laboratory plasmas and for the Sun-Earth interaction.
The study of space plasmas turbulence is based on three main approaches: the analysis of data provided by the scientific mission; the development of theoretical models and novel data analysis techniques; the use of numerical simulations (massive computational resources are often required; these are provided by large facilities for high performance computing, such as CINECA, or the UNICAL HPCC. Examples are the full characterization of intermittency in solar wind turbulence [Sorriso-Valvo et al. 1999; 2015], and the validation of the theoretical prediction for the scaling law of the energy flux in solar wind turbulence [Sorriso-Valvo et al., 2007].
- Bruno, D. Telloni, L. Primavera, E. Pietropaolo, R. D’Amicis, L. Sorriso-Valvo, V. Carbone, F. Malara and P. Veltri, Radial evolution of intermitency of density fluctuations in the fast solar wind, The Astrophysical Journal 786, 53 (2014), DOI: 10.1088/0004-637X/786/1/53.
- H. K. Chen, L. Sorriso-Valvo, J. Safrankova, Z. Nemecek, Intermittency of solar wind density fluctuations from ion to electron scales, The Astrophysical Journal Letter 789, L8 (2014), DOI: 10.1088/2041-8205/789/1/L8.
- De Vita, L. Sorriso-Valvo, F. Valentini, S. Servidio, L. Primavera, V. Carbone and P. Veltri, Analysis of cancellation exponents in two-dimensional Vlasov turbulence, Physics of Plasmas 21, 072315 (2014), DOI: 10.1063/1.4891339.
- Sorriso-Valvo, G. De Vita, M. Kazachenko, S. Krucker, L. Primavera, S. Servidio, A. Vecchio, B. Welsch, G. Fisher, F. Lepreti, V. Carbone, Sign singularity and flares in solar active region NOAA 11158, The Astrophysical Journal 801, 36 (2015), DOI: 10.1063/1.4891339
- Yordanova, S. Perri, L. Sorriso-Valvo and V. Carbone, Multipoint observation of anisotropy and intermittency in solar-wind turbulence, EPL 110, 19001 (2015), DOI: 10.1209/0295-5075/110/19001.
- Chasapis, A. Retinò, F. Sahraoui, A. Vaivads, Y. Khotyaintsev, D. Sundkvist, A. Greco, L. Sorriso-Valvo, P. Canu, Thin current sheets and associated electron heating in turbulent space plasma, The Astrophysical Journal Letters 804, L1 (2015), DOI: 10.1088/2041-8205/804/1/L1.
- Sorriso-Valvo, R. Marino, L. Lijoi, S. Perri and V. Carbone, Self-consistent Castaing distribution of solar wind turbulent fluctuations, The Astrophysical Journal, 807, 86 (2015), DOI: 10.1088/0004-637X/807/1/86.
- De Vita, A. Vecchio, L. Sorriso-Valvo, C. Briand, L. Primavera, S. Servidio, F. Lepreti and V. Carbone, Journal of Space Weather and Space Climate, 5, A28 (2015), DOI: 10.1051/swsc/2015029.
- Rossi, F. Califano, A. Retinò, L. Sorriso-Valvo, P. Henri, S. Servidio, F. Valentini, A. Chasapis, and L. Rezeau, Two-fluid numerical simulations of turbulence inside Kelvin-Helmholtz vortices: intermittency and reconnecting current sheets, Physics of Plasmas, 22, 122303 (2015), DOI: 10.1063/1.4936795.
- Leonardis, L. Sorriso-Valvo, F. Valentini, S. Servidio, F. Carbone and P. Veltri, Multifractal scaling and intermittency in hybrid Vlasov-Maxwell simulations of plasma turbulence, Physics of Plasmas, 23, 022307 (2016), DOI: 10.1063/1.4942417.
- Pucci, F. Malara, S. Perri, G. Zimbardo, L. Sorriso-Valvo and F. Valentini, Energetic particle transport in the presence of magnetic turbulence: influence of spectral extension and intermittency, Month. Notes R. Astron. Soc. 459, 3395 (2016), DOI: 10.1093/mnras/stw877.
- Vaivads et al., Turbulence Heating ObserveR – satellite mission proposal, J. Plasma Phys. 82, 905820501 (2016), DOI: 10.1017/S0022377816000775.
Other selected publications
- Sorriso-Valvo, V. Carbone, P. Veltri, G. Consolini, R. Bruno, Intermittency in the solar wind turbulence through probability distribution functions of fluctuations, Geophysical Research Letters 26, 1801-1804 (1999), DOI: 10.1029/1999GL900270.
- Carbone, L. Sorriso-Valvo, E. Martines, V. Antoni, P. Veltri, Intermittency and turbulence in a magnetically confined fusion plasma, Physical Review E 62, R49-R52 (2000), DOI: 10.1103/PhysRevE.62.R49.
- Sorriso-Valvo, R. Marino, V. Carbone, A. Noullez, F. Lepreti., P. Veltri, R. Bruno, B. Bavassano, Pietropaolo E., Observation of Inertial Energy Cascade in Interplanetary Space Plasma, Physical Review Letters 99, 115001-1-115001-4 (2007), DOI: 10.1103/PhysRevLett.99.115001.
- Alexandrova, V. Carbone, P. Veltri, L. Sorriso-Valvo, Small-scale energy cascade of the solar wind turbulence, The Astrophysical Journal 674, 1153-1157 (2008), DOI: 10.1086/524056.
- Carbone, R. Marino, L. Sorriso-Valvo, A. Noullez, R. Bruno, Scaling laws of turbulence and heating of fast solar wind: the role of density fluctuations, Physical Review Letters 103, 061102 (2009), DOI: 10.1103/PhysRevLett.103.061102.
- Zimbardo, A. Greco, L. Sorriso-Valvo, S. Perri, Z. Voros, G. Aburjania, K. Chargazia, O. Alexandrova, Magnetic Turbulence in the Geospace Environment, Space Science Reviews 156, 89 (2010), DOI: 10.1007/s11214-010-9692-5.
- Perri, V. Carbone, A. Vecchio, R. Bruno, H. Korth, T. H. Zurbuchen, L. Sorriso-Valvo, Phase-ynchronization, Energy Cascade, and Intermittency in Solar-Wind Turbulence, Physical Review Letters 109, 245004 (2012), DOI: 10.1103/PhysRevLett.109.245004
- Dudok de Wit, O. Alexandrova, I. Furno, L. Sorriso-Valvo, G. Zimbardo, Methods for Characterising Microphysical Processes in Plasmas, Space Science Reviews 178, 693 (2013), DOI: 10.1007/978-1-4899-7413-6_21
- Alexandrova, C. H. K. Chen, L. Sorriso-Valvo, T. Horbury, S. D. Bale, Solar Wind Turbulence and the Role of Ion Instabilities, Space Science Reviews 178, 101, (2013), DOI: 10.1007/s11214-013-0004-8
- Maruca, S. D. Bale, L. Sorriso-Valvo, J. C. Kasper, M. L. Stevens, Collisional Thermalization of Hydrogen and Helium in Solar-Wind Plasma, Physical Review Letters 111, 241101 (2013), DOI: 10.1103/PhysRevLett.111.241101.
Turboplasmas: FP7 European Marie Curie IRSES 2010-269297 , (2011-2014)
Anisotropy and intermittency in solar wind turbulence: ISSI Team, (2014-2015)
Kinetic Turbulence and Heating in the Solar Wind: ISSI Team (2013-2014)