Oscillations in the magnetic field of the solar corona in response to flares near the photosphere

Schrijver, C.J. and Brown, D.S., 2000, Oscillations in the magnetic field of the solar corona in response to flares near the photosphere, Astrophysical Journal, 537, L69-L72. Sponsorship: PPARC

The magnetic field in the outer solar atmosphere is frequently distorted by flares. In some cases, a fraction of the field exhibits a rapidly damped oscillation (Schrijver et al.; Aschwanden et al.). If this is a resonating wave trapped in the field, then the rapid damping requires a viscosity or resistivity that is at least 108 times larger than expected (Nakariakov et al.). We propose instead that some of the field lines are so sensitive to the source positions that rocking motions of the photospheric plasma associated with some solar flares (Kosovichev & Zharkova) cause a few loops to oscillate in (anti)phase in the fundamental mode, with a period and decay rate that are determined largely by the characteristics of the photosphere, saying little about the high atmosphere.

Peer reviewed