  We propose a magnetic confinement nuclear fusion mechanism for the evolution
of a solar flare in solar atmosphere. The mechanism agree with two observed
characteristics of explosive flares and coronal mass ejections (CMEs) that have
proved to be very difficult to explain with previous mechanisms: the huge
enrichments of $^{3}He$ and the high energy gamma ray radiation. The twisted
magnetic flux rope is a typical structure during the solar flares, which is
closely related to the solar active region that magnetic fields have almost
complete control over the plasma. Consequently, the plasma inside the flux rope
is heated to more than 1.0$\times10^{7}$ K by adiabatic compression process,
and then the thermonuclear fusion can take place in the flux rope accompanied
with high energy gamma rays. We utilize the time-dependent ideal
2.5-dimensional magnetohydrodynamic (MHD) simulation to demonstrate the
physical mechanism for producing flares, which reveals three stages of flare
development with process of magnetic energy conversion and intense release
during the solar flares and CMEs in solar atmosphere. Furthermore, we discuss
the relationship between magnetic reconnection and solar eruptions.

Solar and Stellar Astrophysics