Context. The quiet Sun presents magnetized plasma whose field strengths vary from zero to about kG. The probability density function of the magnetic field strength efficaciously describes the statistical properties of the quiet Sun magnetic field.Aims. We simulate the dynamics and the evolution of quiet Sun magnetic elements to produce a probability density function of the field strengths associated with such elements.Methods. The dynamics of the magnetic field are simulated by means of a numerical model in which magnetic elements are driven passively by an advection field characterized by spatio-temporal correlations that mimick the granulation and mesogranulation scales observed on the solar surface. The field strength can increase due to an amplification process that occurs where the magnetic elements converge. Starting from a -like probability density function centered on G, we obtain magnetic field strengths of up to kG (in absolute value). To derive the statistical properties of the magnetic elements, several simulation runs are performed.Results. Our model is able to produce kG magnetic fields in a time interval of the order of the granulation timescale. The mean unsigned flux density and the mean magnetic energy density of the synthetic quiet Sun reach values of G and G respectively in the stationary regime. The derived probability density function of the magnetic field strength decreases rapidly from G to G and has a secondary maximum at kG. From this result, it follows that magnetic fields G dominate the unsigned flux density and magnetic energy density, although the probability density function of the field strength reaches a maximum at G.Conclusions. A photospheric advection field with spatio-temporal correlations, driving the magnetic elements, and reduced magnetic amplification rules are able to create a realistic probability density function of the quiet Sun magnetic field. It has been found that they naturally produce an excess of magnetic fields around kG if an upper limit is imposed on the field strength.

Berrilli, F., DEL MORO, D., Viticchie', B. (2008). Magnetic field distribution in the quiet Sun: a simplified model approach. ASTRONOMY & ASTROPHYSICS, 489(2), 763-767 [10.1051/0004-6361:200809683].

Magnetic field distribution in the quiet Sun: a simplified model approach

BERRILLI, FRANCESCO;DEL MORO, DARIO;
2008-01-01

Abstract

Context. The quiet Sun presents magnetized plasma whose field strengths vary from zero to about kG. The probability density function of the magnetic field strength efficaciously describes the statistical properties of the quiet Sun magnetic field.Aims. We simulate the dynamics and the evolution of quiet Sun magnetic elements to produce a probability density function of the field strengths associated with such elements.Methods. The dynamics of the magnetic field are simulated by means of a numerical model in which magnetic elements are driven passively by an advection field characterized by spatio-temporal correlations that mimick the granulation and mesogranulation scales observed on the solar surface. The field strength can increase due to an amplification process that occurs where the magnetic elements converge. Starting from a -like probability density function centered on G, we obtain magnetic field strengths of up to kG (in absolute value). To derive the statistical properties of the magnetic elements, several simulation runs are performed.Results. Our model is able to produce kG magnetic fields in a time interval of the order of the granulation timescale. The mean unsigned flux density and the mean magnetic energy density of the synthetic quiet Sun reach values of G and G respectively in the stationary regime. The derived probability density function of the magnetic field strength decreases rapidly from G to G and has a secondary maximum at kG. From this result, it follows that magnetic fields G dominate the unsigned flux density and magnetic energy density, although the probability density function of the field strength reaches a maximum at G.Conclusions. A photospheric advection field with spatio-temporal correlations, driving the magnetic elements, and reduced magnetic amplification rules are able to create a realistic probability density function of the quiet Sun magnetic field. It has been found that they naturally produce an excess of magnetic fields around kG if an upper limit is imposed on the field strength.
2008
Pubblicato
Rilevanza internazionale
Articolo
Sì, ma tipo non specificato
Settore FIS/05 - ASTRONOMIA E ASTROFISICA
English
Sun; magnetic fields; photosphere
Berrilli, F., DEL MORO, D., Viticchie', B. (2008). Magnetic field distribution in the quiet Sun: a simplified model approach. ASTRONOMY & ASTROPHYSICS, 489(2), 763-767 [10.1051/0004-6361:200809683].
Berrilli, F; DEL MORO, D; Viticchie', B
Articolo su rivista
File in questo prodotto:
File Dimensione Formato  
aa09683-08.pdf

accesso aperto

Tipologia: Versione Editoriale (PDF)
Licenza: Copyright dell'editore
Dimensione 515.93 kB
Formato Adobe PDF
515.93 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2108/8438
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 3
  • ???jsp.display-item.citation.isi??? 2
social impact