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	Figure 1: A typical hard X-ray (25-300 keV) solar flare with quasi-periodic pulsations, observed in full disk measurements by RHESSI on the 19th of January, 2005. The event is associated with a flare of class X1.3 (peaking at 08:22 UT, as seen by GOES 1-8 Å).
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In the text

Figure 2: A sketch of the mechanism for the generation of quasi-periodic pulsations of solar and stellar flaring emission. The cool (shaded) loop experiences fast magnetoacoustic oscillations (e.g., kink or sausage mode). A segment of the oscillating loop is situated nearby a flaring arcade. An external evanescent or leaking part of the oscillation can reach magnetic null points in the arcade, inducing quasi-periodic modulations of the electric current density. The resulting current driven plasma micro-instabilities are known to cause anomalous resistivity, which triggers magnetic reconnection. This periodically accelerates particles, which follow the field lines and precipitate in the dense atmosphere, causing quasi-periodic emission in radio, optical and X-ray bands.

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In the text

Figure 3: Time evolution of the maximum electric current density in the vicinity of a 2D magnetic neutral point. The current is generated by a harmonic fast magnetoacoustic wave with period of 5 time units, coming towards the neutral point. The initial relative amplitude of the wave is 1.5%. The plasma  is finite. The normalising values are the magnetic field strength and the Alfvén speed at the domain boundary, and the characteristic spatial scale of the field inhomogeneity.

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In the text