Relating to monitoring

• US 20060219518A1
• Filed: 03/31/2006
• Published: 10/05/2006
• Est. Priority Date: 03/31/2005
• Status: Active Grant

• Current Assignee: VT Nuclear Services Limited (Babcock International Group PLC)
• Original Assignee: BIL Solutions Ltd. (Babcock International Group PLC)
• Inventors: Lightfoot, John Adrian, Ronaldson, John Paul
• Granted Patent: US 7,698,099 B2
• Time in Patent Office: Days
• US Class Current: 194/317
• CPC Class Codes: G01T 3/00 Measuring neutron radiation G01T5/00 takes precedence

Abstract

A method of monitoring radioactive emissions includes: obtaining a data set, the data set including a record of an event, together with an indication of the time of the event and/or the detector which detected the event; and processing the data set, the processing including the analysis of at least a part of the data set according to a first set of criteria to provide a first analysed data set and analysing at least a part of the data set according to a second set of criteria to provide a second analysed data set, one or more criteria of the second set being different to the criteria of the first set.

Claims

1. A method of monitoring radioactive emissions, the method comprising:

obtaining a data set, the data set including a record of an event, together with an indication of the time of the event and/or the detector which detected the event; and

processing the data set, the processing including the analysis of at least a part of the data set according to a first set of criteria to provide a first analysed data set and analysing at least a part of the data set according to a second set of criteria to provide a second analysed data set, one or more criteria of the second set being different to the criteria of the first set.

2. The method according to claim 1 in which one or more of the criteria are the time between an occasion and the start of the time period and/or the time between an occasion and the end of the time period and/or the time period between the start of the time period and the end of the time period.

3. The method according to claim 1 in which the first set of criteria includes a first length of time between the start of a time period and the end of a time period and the second set of criteria includes a second different length of time between the start of the time period and the end of the time period.

4. The method according to claim 3 in which the first time period is a measure of the real and accidental coincidences in the events, with the second time period being a measure of the accidental coincidences.

5. The method according to claim 4 in which the distribution of the number of events falling within the time periods is considered.

6. The method according to claim 1 in which the selected set of criteria is selected to give a length of time period which excludes times at which only accidental coincidences occur.

7. The method according to claim 1 in which the selected set of criteria is selected to give a length of time period for which real coincidences occur below a threshold rate.

8. The method according to claim 1 in which different sets of criteria are applied to the events detected by different detectors.

9. The method according to claim 8 in which the first set of criteria is applied to events detected by a first type of detector and the second set of criteria to events detected by a second type of detector.

10. The method according to claim 1 in which the first set of criteria is the time between an event and an event which is n events later, where n is a positive integer and the second set is the time between an event and an event which is m events later, where m is a positive integer and is different to n.