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10 October 2008

Answer to Question #1307 Submitted to "Ask the Experts"

Category: Instrumentation and Measurements — Instrument Calibration (IC)

The following question was answered by an expert in the appropriate field:

Why does a yellow solution have the greatest quenching effect when performing liquid scintillation counting?

There are many things that will interfere with the production of scintillations, or detection of this emitted light by a photomultiplier tube(s), in liquid scintillation counting. A chemical may actually absorb some beta energy, or it may absorb the light emitted by the scintillator. This "color quenching" would be greatest if the chemical absorbs strongly at the wavelengths being emitted. Though I can't find any specific wavelength data, I suspect a yellow solution would fit this scenario. David J. Allard, CHP

Answer posted on 5 November 2001. The information and material posted on this Web site is intended as general reference information only. Specific facts and circumstances may alter the concepts and applications of materials and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice specific to whatever facts and circumstances are presented in any given situation. Answers are correct at the time they are posted on the Web site. Be advised that over time, some requirements could change, new data could be made available, or Internet links could change. For answers that have been posted for several months or longer, please check the current status of the posted information prior to using the responses for specific applications.