Experimental setup of the detector system, consisting of the absorption filter and the ESFADOF edge filter. Two separate taperedamplifiers (TAs) are used for optical pumping of the vapors. The upper part shows the water tube system, in which Brillouinscattered light is generated by the pulsed fiber amplifier. Abbreviations: wave plate (λ/2, λ/4), polarizing beam splitter cube (PBS),temperature sensor (Pt100), lens (L), pinhole (P), dichroic mirror (DM), mirror (M), rubidium vapor cell (Rb), tapered amplifier (TA),bandpass filter (BP), photomultiplier tube (PMT).