抄録
The gamma ray dose at 2.05 km ground distance from the Hiroshima atomic bomb hypocenter was measured from roof tile samples by a thermoluminescence technique. Two tile samples collected at 2.45 km also were analyzed to check the reliability of the background estimates. The result for the 2.05 km distance was 129±23 mGy for five-tile sample average. This value is 2.2 times larger than the corresponding DS86 estimate. These results and those in the literature show the DS86 estimate is 50% or less of the measured value 2.05 km from the Hiroshima hypocenter.
