Typical specifications are summarized in Table 2 2 Since many different types are available, the values in the table have been entered as ranges

Tables 2 3 through 2 7 indicate the variety of neutron and gamma sensors available from one manufacturer The sensors listed are limited to those discussed in this chapter Commercial in-core neutron sensors are described in Chap 3

Table 2 2—Typical Specifications for Commercial Out of-Core Gas Ionization Detectors Gamma chambers Ionization chambers Compensated ionization chambers Fission counters Proportional counters Sensitivity amp/(R/hr) amp/nv* (counts/sec)/nv* 10 1 3 to 10 9 10 12 to 10 1 0 10 1 4 to 5 x 10 1 3 — v о о ^Ч т-Н 0 0 о о ^Ч г*Ч 10 4 to 2 3 to 40 Operating voltage 100 to 1500 200 to 1200 200 to 1500 200 to 1200 800 to 5000 Max temp °I 175 to 600 175 to 850 175 to 750 250 to 850 175 to 500 Diameter in 1 to 3 1 to 3 5 3 to 4 0 1 to 3 1 to 6 Length in 12 to 16 10 to 16 8 to 25 5 to 300 10 to 40 •Where nv is measured in neutrons cm 2 sec 1

Table 2.3—Uncompensated Ionization Chambers* Nominal dimensions Neutron- sensitive material Thermal- neutron sensitivity, amp/nvt Gamma sensitivity, amp/(R/hr) Max. oper. thermal — neutron flux, nvt Typical oper. voltage, volts (d-c) Min signal resistance, ohms Signal capacitance, pF Max. oper. temp., °F Detector insulator І Length Sensitive, in. Overall, in. Detector O. D., in. 2 3 5 u 1 4 х 10 1 3 4 2 x 10’1 1 1 4 X 10’0 300-1000 109 150 300 ai2o3 6 n1/, 2 1 °B 4 4 х КГ1 4 4 5 x 10’1 1 5 0 x 10′ 0 200-1000 10′ 1 170 300 ai2o3 7 135/, 3 IJSU 2 6 х 1ЄГ1 4 3 0 x10 1 1 8 5 x 10‘ 0 300-1000 10’ 140 300 ai2o3 6 11 y2 2 ”SU 3 0 х10 1 4 4 2 x10 1 1 6 0 X 10′ 0 300-1000 109 150 300 ai2o3 6 11‘/2 2 2 3 5 u 1 4 х10 1 4 42×10" 1 4 x 10′ 1 300-1000 109 150 300 ai2o3 6 u1/. 2 1 °B 4 4 х10 1 4 4 5 x 10" 1 5 0 x 10‘ 0 200-1000 10′ 0 170 575 ai2o3 7 3 2 3 3 и 40 х 10 1 4 40 x 10" 1 2 7 X 10′ 0 200 1000 10" 160 575 ai2o3 7 135/s 3 2 3 5 u 1 4 х 10" 3 4 2 x 10 1 ‘ 1 4 X 10’0 300-1000 109 150 300 ai2o3 6 11’/, 2 10 в 4 4 х10 1 4 4 5 x 10" ‘ 50×10’° 200-1000 10‘ 1 170 300 ai2o3 7 “7. 3 10 в 1 5 х10 14 3 5 x 10 1 2 5 0 x 10 1 0 300 800 10′ 3 110 175 Rex 5‘/2 10’/2 3‘/2 2 3 5 U 2 8 х 10" 4 40 x 10" ‘ 5 0 x 10′ 0 300 1000 109 170 500 ai2o3 7 135/8 3 2 3 5 и 5 1 х 10 1 4 5 0 x 10" 1 2 7 x 10’0 300-1000 107 283 850 ai2o3 10 157. 17. 2 3 5 и 40 х 10 1 4 4 0 x 10 1 1 2 7 x 10’0 300-1000 107 150 700 ai2o3 7 135/8 3 2 3 5 и 1 4 х 10 1 3 4 2×10» 1 4 X 10‘ 0 300-1000 10* 1000 390 ai2o3 6 276 3 . ов 1 2 х 10 1 4 3 0 x 10 1 2 1 0 x 10’0 200 1000 10′ 2 1880 175 ai2o3 10 15/s 1 10 в 3 0 х 1 O’1 3 1 8 x 10" 0 2 5 x 10′ 0 300-1100 10′ 3 1850 175 Rex 108 1133/8 3‘/2 *Courtesy Westwghouse Electric Corp. +Nv is expressed in neutrons cm 2 sec 1 tAl2 Oj is a high alumina content ceramic Rex is a cross linked styrene

*Courtesy Westinghouse Electric Corp. + Nv is expressed in neutrons cm 2 sec 1 $a2o3 is a high alumina-content ceramic, Rex is a cross-linked styrene

VJ 00

Table 2.4—Compensated Ionization Chambers* Thermal- Uncomp. Max. oper. Typical Min. Max. Nominal dimensions Length Sensitive, Overall, neutron sensitivity, gamma sensitivity, thermal- neutron oper. voltage, signal resistance, Signal capacitance, oper. temp., Insulation type$ Detector O. D., amp/nvt amp/(R/hr) flux, nv+ volts (d-c) ohms pF "F Detector Conn. in. in. in.

4 4 x 10 1 4 2 3 x10 1 1 2 5 xlO10 300-1000 10’4 275 175 Rex Rex 14 2 37, 3’/. 4 4 x 10" 4 2 3×10" 2 5 x 10′ 0 300-1000 10′ 4 275 175 Rex Rex 14 24’/я з1/. 4 4 x 10 1 4 2 5 x 10Г1 1 2 5 x 1010 300-1000 10′ 2 315 575 ai2o3 ai2o3 14 2il 3’/. 4 4 x 10’4 2 3 x 10" 1 2 5 x 10′ 0 300-1000 10′ 3 275 175 Rex Rex 14 2 Я ЗУ, 1 5 x 10Г14 3 5 x 10 1 2 2 5 x 10′ 0 300-800 10′ 3 130 175 Rex Rex 5’/, ю У, ЗУ, 1 5 x10 1 4 3 5 x 10" 2 25×10’" 300-800 10′ 3 135 175 Rex Rex 5’/2 ю ■/, з1/, 4 4 x10’4 2 3×10" 25×10’" 300-1000 10′ 3 290 400 ai2o3 ai2o3 14 !9’/8 з1/. 1 0 x 10 1 5 1 5 x10 1 3 1 5 x 10‘2 25-250 101 1 155 660 ai2o3 ai2o3 2У16 75/>6 3 4 4 x10 ’ 4 2 3 x 10 1 1 2 5×10" 300-1500 10′ 3 290 300 ai2o3 ai2o3 14 19’/, ЗУ.

Table 2.5—Fission Counters’ Thermal — neutron sensitivity, (counts/sec)nv + Max. oper thermal — neutron flux, nv + Typical oper. voltage, volts (d-c) Min. signal resistance, ohms Signal capacitance, pF Max. oper. temp., °F Insulator type;;: Detector Conn Nominal dimensions Length Detector O. D., in Sensitive, in. Overall, in 0 7 14x10s 200-800 109 150 300 ai2o3 ai2o3 6 ny 2 0 2 5 0 x 105 200-800 10“ 140 300 ai2o3 ai2o3 6 11 у 2 0 14 7 0 x 10s 200-800 109 150 300 ai2o3 ai2o3 6 ny 2 1 25 x 10 3 10×10* 250 500 109 55 575 ai2o3 Rex % 5 35/1 6 0 210 0 52 2 0 x 10s 200-800 109 150 300 ai2o3 ai2o3 6 11У 2 0 07 1 4 x 10‘ 200-800 109 150 300 ai2o3 ai2o3 6 11У 2 0 7 1 4 x 10s 200-800 109 160 575 ai2o3 ai2o3 7 13s/8 3 0 7 1 4x10s 200 800 109 150 300 ai2o3 ai2o3 6 ny 2 0 7 1 4 x 105 200 800 107 150 700 Al2 O3 ai2o3 6 11У 2 0 1 1 0 x 10" 300 800 109 30 575 ai2o3 ai2o3 4% ?7. 1 0 14 7 0 x 10s 200 800 109 170 500 ai2o3 ai2o3 7 13 % 3 0 5 2 0 x 10 s 200 800 10 7 283 850 ai2o3 ai2o3 10 15 7. 1% 0 25 4 0 x 105 200 800 107 150 700 ai2o3 ai2o3 7 3 3 % 3 5 x 10 3 2 0 X 108 350 650 1010 40 750 ai2o3 1 5 2 0 7 14 x10s 75 109 160 500 ai2o3 — 7 14 3 0 35 2 8 x 10s 200 800 109 150 300 ai2o3 ai2o3 6 ny 2 § lOx 10′ 200 800 109 150 300 ai2o3 ai2o3 6 11У 2 0 7 14×10’ 200-800 108 1000 390 ai2o3 ai2 o3 6 276 3 2 2 x 10 4 5 0 x 108 250 800 5 x 108 2 500 alo3 — 5/1(, 1’/,. 0 220 1 5 x 10 3 1 0 x 108 300- 500 108 260 500 ai2o3 A1,03 7, 243 0 210 1 x 10-5 10×10” 100-200 109 125 250 I h Rex ■Уза 6з5/,6 0 090 0 18 6 0 x 10s 200-800 109 45 575 ai2o, ai2o3 «7. 12 1 0 5 2 0 x 10s 200-800 108 150 390 a 12 0 3 ai2o3 6 ny 2 0 35 3 0 x 10s 200 800 108 90 390 ai2o3 ai2o3 3 "У 2 *Courtesy Westtnghouse Electric Corp. + Nv is expressed in neutrons cm 2 sec 1 $A1203 is a high alumina-content ceramic Rex is a cross linked stvrene §Sensitive material is 238 U Sensitivity to ^ 1 5 MeV neutrons = 10 3 to thermal neutrons = 1 4 x 10 4

Chi SO

‘Courtesy Westinghouse Electric Corp.

+ Nv is expressed in neutrons cm"2 sec 1

*A1303 is a high-alumina-content ceramic, Rex is a cross linked styrene §Oval case 7l s/ in and 3^ 6 in

Table 2.7—Gamma Chambers* Nominal dimensions Gamma sensitivity, amp/(R/hr) Max oper. gamma flux, R/hr Typical oper. voltage, volts (d-c) Min signal resistance, ohms Signal capacitance, pF Max. oper. temp., °F Detector insulator t Length Detector O. D., in Sensitive, in. Overall, in. 3 0 x10 1 2 4 x 10s 200-1000 101 2 1880 175 ai2o3 10 15‘/8 і 10×10“ 5 x 107 100 1200 10′ 3 125 575 ai2o3 8 123/8 2 1 0 x 10 1 0 3 x 107 100-1200 10‘ 3 125 575 Ai203 8 123/8 2 2 5 x 10 9 2 x 103 200-1500 10‘ 1 170 300 ai2o3 7 13?8 3

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