  The existence of axial (poloidal) magnetic field in a plasma focus and its
significance in plasma focus phenomenology has been extensively discussed in a
recent review paper. The poloidal magnetic field is a part of the transient
3-dimensional magnetic field structures which arise spontaneously, accelerate
ions and keep them moving in trajectories that repeatedly cross a dense and
warm plasma target. This is the origin of the abnormally high fusion reaction
rate of the plasma focus, which has been known since the 1960s but has begun to
be understood quite recently. Further progress now depends on explorations of
the global aspects of the evolution of poloidal magnetic field. However,
well-known experimental difficulties involved in standard techniques of axial
magnetic field measurement hamper such research efforts. Taking cognizance of
this stalemate, the International Scientific Committee for Dense Magnetized
Plasmas launched an initiative to address this state of affairs in an
International Video Conference on 24th April 2020. This paper reports on the
first experiments that resulted from that initiative

Plasma Physics