The forward peaking radiation pattern of a single particle with an
increasing particle velocity is well-established knowledge. Further
details of a single particle radiation pattern suggest that a particle
also has a backward peaking radiation pattern and two associated
asymmetries coming from the Doppler and spiral trajectory bremsstrahlung
effects. Relativistic particle under periodic motion emits spiral
radiation pattern which is measured as short pulses by the sensors.
However, the transition from peaking to spiral radiation pattern as
particle transits from discrete to continuous periodic motion is not
clear. This paper reports a possible physical asymmetric effect caused
by the bremsstrahlung spiral trajectory that could be responsible for
the spiral radiation pattern emitted by the periodic particle motion.
The bremsstrahlung asymmetry changes within each period that change the
radiation intensity symmetry continuously, within a specific minimum and
maximum range. This maximum and minimum range is defined by the limits
of the bremsstrahlung asymmetry, R. This change in radiation intensity,
independent of particle periodicity, emits circular waves of the varying
radius that forms a spiral radiation pattern. Hence, the spiral of a
periodic motion comes from a parameter, R, that is independent of
periodicity. Hence, parameter R can change during a period by preserving
the periodicity of the incoming particle motion. Overall, a continuous
periodic motion is important in predicting the experimental observations
as incoming particle interacts with multiple target particles meaning
the same bremsstrahlung process repeats periodically.