A WHITE CELL TYPE MULTIPLE REFLECTION SYSTEM FOR TROPOSPHERIC RESEARCH

A White cell type multiple reflection system (MRS) for long path absorption measurements is reported which makes use of the reinjection technique. The set-up of this MRS system was optimized by model calculations and compared with other suggested designs in field measurements. In pilot tests the performance of the system and the applicability to troposheric measurements were tested. Using a 6 m mirror system an absorption path length of 1.2 km was realized under field condition just despite of the open path set-up. No problems with atmospheric fluctuations affected the measurements for the chosen path length. In the laboratory an optical path length of 2.5 km was achieved. Thus, this MRS design is very interesting for applications both inside and outside the laboratory.