Diode-laser absorption computerized tomography is applied to the diagnosis
of the plume generated by an arcjet thruster A protection stack is designed
to carry a laser beam into the arcjet flow field at any location in the va
cuum chamber. The experimental system is developed to reconstruct the maps
of the temperature and the atomic number density by utilizing a small numbe
r of line-of-sight measurements. It has been demonstrated to be a convenien
t and useful method for the measurement of plume parameters and for monitor
ing the performance of the arcjet.