We report the first observation of a high-density (5 cm-3) plasma region with low perpendicular temperature (less than 30 eV) in the plasma sheet boundary layer. We used several experiments on board the ISEE spacecraft. The plasma density is determined by the relaxation sounder. The hot particle and magnetic field measurements show that high-density regions are observed next to the region of high hot particle fluxes, and they also put an upper limit on the perpendicular temperature of the dense plasma population. Current sheets flowing primarily in the ¿Y direction for this event are identified using their magnetic signature in the region of hot particle gradient. |