  The temporal recurrence of micro-flare events is studied in a time interval
before and after of major solar flares. Our sample is based on the x-ray flare
observations by the Geostationary Operational Environmental Satellite (GOES)
and Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). The analysed
data contains 1330/301 M- and X-class GOES/RHESSI energetic solar flares and
4062/4119 GOES/RHESSI micro-flares covering the period elapsed since 2002. The
temporal analysis of recurrence, by Fast Fourier Transform (FFT), of the
micro-flares shows multiple significant periods. Based on the GOES and RHESSI
data, the temporal analysis also demonstrates that multiple periods manifest
simultaneously in both statistical samples without any significant shift over
time. In the GOES sample, the detected significant periods are: $11.33$,
$5.61$, $3.75$, $2.80$ and $2.24$ minutes. The RHESSI data shows similar
significant periods at $8.54$, $5.28$, $3.66$, $2.88$ and $2.19$ minutes. The
periods are interpreted as signatures of standing oscillations, with the
longest period ($P_{1}$) being the fundamental and others as higher harmonic
modes. The period ratio of the fundamental and higher harmonics ($P_{1}/P_{N}$)
is also analysed. The standing modes may be signatures of global oscillations
of the entire solar atmosphere encompassing magnetised plasma from photosphere
to corona in active regions.
