RNTs PKh obtained the average radiation power values for two operational substances using PDISPL model, which are presented in tables 1,2 together with the calculated data. The discrepancy between the calculated and the experimental data is due to both the non-considered in the calculation process inhomogeneity of the operational substance in the laser cell and de-adjustment of resonator due to heating of the whole construction resulting in the interrupted generation.

In the course of the experiments implementing pumping by xenon lamps it was stated that big gradients of the temperature field at the area of laser cell become a serious obstacle for stable laser radiation.

To avoid this the alternative pumping method was studied on the basis of mercury arc lamps featuring high efficiency (about 50%) within the pumping band of the active medium.

The cell having 1,4 cm interior diameter and 67 cm length between the inlet and outlet of the operating gas was used. The cell windows are located at Bruster angle in parallel planes. The pumping was done by 8 low pressure mercury arc lamps. The illuminating element is presented in fig. 5.

Resonator is formed by flat mirrors with reflecting ratios 99,8% and 95%.

The total power of pumping lamps at the resonance mercury line wavelength of 254 nm is not less than 160 W. The effective pumping surface (fig. 6) is about ~270 cm2. The calculated photo-dissociation ratio у is within 0.16-0.18sec-1.

The following results were obtained.

The velocity of gas flux along the cell when one cryogenic pump is used, measured at the absence of generation was 1020 cm/sec. For CF3I composition the generation power of 180 mW was obtained. After activation of the second cryogenic pump (gas velocity was not

specified) the generation power increased up to 245 mW. The optimum generation pressure was 25 mmHg.

Overlightning can be seen at the edges of the display caused by the pumping lamps. Registration sensitivity decreases from periphery to the center.

Relative generation power was specified for C3F7I. The mirror with 2% transmittance and ~ 6 m radius was used as the outlet one. Generation power was 50% of the power recorded for CF3I.

Thus, mercury lamps used as the alternative pumping source offer stable generation, parameters of which provide for applicability of the model for follow-up applied research.