COHERENCE TRANSFER BETWEEN ROTATION-INVERSION TRANSITIONS, IN THE v3 FUNDAMENTAL OF NH3
نویسندگان
چکیده
The study of the absorption profile of the uI ‘R 44 and pP SB lines of ammonia at various pressures is reported. The two lines of the observed inversion doublets broaden as the pressure is increased until they overlap. Once the lines have overlapped the spectral profile narrows and then begins to broaden again but at a markedly different rate. This effect is due to collisions which transfer coherence (often called cross relaxation) between the transitions of the given inversion doublets. Modeling of this effect shows that the rate of coherence transfer is 71% and 75% of the total collisional dephasing rate for the ‘R 4, and pP S8 lines, respectively.
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