What was the total correction factor between the count rate and the activity of the system used to count 131I mounted on Mylar?
9-6. A 131I standard solution was obtained from the National Bureau of Standards (NBS). The following information was supplied concerning the solution: assay of 131I at 8 A.M., January 1, 2.09 × 104 dps/mL } 2%. On January 15 at 8 A.M., a sample of 131I was counted. This sample had been obtained from a […]
Explain how variations in the observed counts caused by fluctuations in the sensitivity of the counting system can be compensated.
9-7. A series of radioactive samples of short half-life will be counted one per day over several days. Explain how variations in the observed counts caused by fluctuations in the sensitivity of the counting system can be compensated. 9-8. A pulse height spectrum for 131I (γ ray of 0.393 MeV) was obtained with a single-channel pulse […]
What are the estimated standard deviation and the percent estimated standard deviation of the sample count rate corrected for background?
10-8. A 2048×2048×12-bit image is compressed at 10 to 1 compression ratio. How many bits are present in the compressed image? 11-1. Suppose 3600 counts were accumulated for a sample counted for 10 minutes. Background contributed 784 counts over a counting interval of 6 minutes. a. Find the estimated standard deviation and the percent […]
Describe the researcher’s original results in terms of bias, precision, and accuracy.
11-2. A medical researcher carefully measures the length of the fetal humerus in 50 ultrasound studies by using electronically generated distance-measuring “calipers” on the display. The researcher obtains a mean value of 5.5 cm with a standard deviation of 2 mm. After the measurements have been obtained, the researcher discovers through studies of […]