Neutron Detectors - NP Series
2Pages

The NP Seriesprovides custom-ers with the capability ofdetecting slowand fast neutrons and measurementof tissue equiva-lent dose rate of the neutron field.The detectorscontain a propor- tional counterwhich producespulses resulting from neutroninteractions within it. The probes contain components which moderateand attenuate neutrons so that the net incident flux at the proportional counter is a thermal and low epithermal flux representative of the tissueequivalent dose rate and the neutron field.The neutron probe also contains a Circuit Card Assembly (CCA),Amplifier and Logic, and a CCA High Voltage supply.The NP Series of detectors are SMART probes, which retain probeinformation in non-volatile memory. When calibrated, data such asprobe calibration constants and identifying information are stored and verified in the EEPROM memory in the probe circuitry. Thisarrangement allows the Canberra NP Series detectors to beinterchangeable.The NP Series of detectors are ֓maintenance free in design and requireno routine servicing or preventive maintenance.The NP Series can be connected to multifunction control anddisplay units such as ADM606, ADM606M, ADM616, and ADM616S. Designed to respond tothermal, epithermal andfast neutrons Measurement of tissueequivalent dose rate of theneutron field SMART probe retains probeinformation in non-volatilememory > 3 He/BF > 3 proportionalcounter > 10 B attenuator Polyethylene moderator Excellent linearity andaccuracy Detectors are easilyinterchanged Optional mounting bracket > The NP Series detectors are designed and manufactured under a quality system incompliance with the follow-ing standards and require- ments: ISO 9001 10CFR21 10CFR50, Appendix ԓB > Principle of Operation IEEE-730 Due to the fact that neutrons have no charge, they can only be detected indirectly through nuclear reactions that create charged particles. TheNP100B detector uses ANSI/ASME NQA-1, ANSI/ ASME NQA-2, Part 2.7 > 10 B, whereas the NP100H uses > 3 He as theconversion target. The charged particle Ԗ alpha or proton (respectively) created in the nuclear reaction ionizes the gas.The detector is housed in a polyethylene moderator with high hydro-gen content. The hydrogen presents a large scattering section to the neutrons. Through elastic collisions with the hydrogen atoms the fastand epithermal neutrons give up a large part of their energy and arereduced to thermal neutrons.A cylindrical attenuator containing > 10 B isotope surrounds an innermoderator which contains the proportional counter. > Phone contact information Benelux/Denmark (32) 2 481 85 30 Canada 905-660-5373 ? Central Europe +43 (0)2230 37000 ? France (33) 1 39 48 57 70 ? Germany (49) 6142 73820 Japan 81-3-5844-2681 ? Russia (7-095) 429-6577 ? United Kingdom (44) 1235 838333 ? United States (1) 203-238-2351 For other international representative offices, visit our Web Site: http://www.canberra.com or contact the Canberra U.S.A. office.C10269 3/03 Printed in U.S.A. size="-5">