Measurement of the 14C Content in Liquid Scintillators by Means of a Small-Volume Detector in the Low-Background Chamber of the Baksan Neutrino Observatory

A setup for measuring natural-radioactivity backgrounds and ultralow concentrations of the isotope ¹⁴C in samples of a liquid organic scintillator was created at the low-background laboratory of the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences) at a depth of 4900 mwe. The concentration of the radiocarbon ^14C in a sample of a scintillator based on domestically produced linear alkylbenzene was measured, and it was found that ¹⁴C/¹²C (3.3 ± 0.5) × 10^‑17.