Diode-laser absorption tomography is described with which the spatial tempe
rature and the atomic number density distribution of a 3-kW class arcjet ca
n be derived simultaneously by reconstruction of the absorption coefficient
field of the arcjet's argon exhaust plume. One can perform various paramet
er measurements by changing the arcjet's mass-how rates and discharge curre
nts. The maximum temperature and atomic number density increase with the ma
ss-flow rate and the discharge current. The trend for increase is not alway
s found for a specific input power, although at a fixed mass-flow rate the
power increases at that rate. (C) 2001 Optical Society of America. OCIS cod
es: 280.2490, 300.1030, 300.6260, 350.5400.