• • fi

The range of the out-of-core counting, system is 1.4 nv. to 1.4 x 10 nv (see Figure 8-11).

fi •

This system provides 1 count/sec at startup and 10° counts/sec at the upper end of the range.

Pulse overlap becomes large above 10 counts/sec, thus limiting the range of the system at this level. .

This particular chamber can be used up to300°C (aluminum limits the temperature). A

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titanium fission counter of a similar design, with a specified life of 10 nvt, can be used up to 1000° F. The system uses the identical electronics as is used in the in-core system, except that a higher voltage polarizing power supply may be used if desired.