The translational temperatures and densities of metastable He atoms (2~3S_1-2~3P_0) in the multi-Micro Hollow Cathode Lamp were measured by diode laser absorption spectroscopy. The absorption profile of metastable He atoms was obtained by scanning the wavelength of the diode laser in the micro hollow cathode discharge (MHCD). Moreover, it was found that the absorption profile of metastable He atoms shifts from a Gaussian to Voigt profile at a pressure of ～10 kPa. The metastable He atoms temperatures were estimated to be 900 to 1150 K, and the densities were measured to be 1.3×10~(13) cm~(-3) to 7.6×10~(12) cm~(-3) in the range of 5 to 30 kPa. The translational temperatures and densities of metastable He atoms decreased with increasing pressure to 10 kPa, on the other hand, increased with increased pressure in the range from 10 to 30 kPa.
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