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US3780289A Expired / Lapsed US ⏱️ 0.0 years remaining

Quench correction in liquid scintillation counting

Assignee: GD Searle LLC
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Filing: 1972-02-10
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Granted: 1973-12-18
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Expires: 1992-02-10
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Abstract

Abstract A means for determining counting efficiency in a liquid scintillation system. Pulse amplitudes are accumulated as are the number of pulses contributing thereto. The accumulated pulse amplitude sum is divided by the accumulated number of pulses to produce an average pulse amplitude for the pulses measured. The average pulse amplitude may be correlated to average detection efficiency by an ascertainable function. Through average efficiency of detection the actual rate of radioactive disintegrations may be computed from the count rate measured.

Inventors

  • 👤 G Kulberg
  • 👤 R Deinert

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 02:48
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/16; G01T1/20; G01T1/204; G01T1/2042; G01T1/2045

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 109 words
A method for determining counting efficiency using a liquid scintillation radiation detecting and counting apparatus having pulse amplitude accumulative means for pulses generated by photodetecting means as a result of scintillations caused by radioactive events in a liquid sample containing a known radioactive source comprising: passing the aforesaid pulses to said pulse amplitude accumulative means to produce a cumulative integral sum of pulse amplitudes, counting the number of pulses contributing to the cumulative integral sum of pulse amplitudes, dividing the integral sum of pulse amplitudes by the number of pulses to ascertain an average pulse amplitude, and determining average pulse collection efficiency as a function of average pulse amplitude.
Claim 2
Independent Claim 109 words
A method for determining counting efficiency using a liquid scintillation radiation detecting and counting apparatus having pulse amplitude accumulative means for pulses generated by photodetecting means as a result of scintillations caused by radioactive events in a liquid sample containing a known radioactive source comprising: passing the aforesaid pulses to said pulse amplitude accumulative means to produce a cumulative integral sum of pulse amplitudes, counting the number of pulses contributing to the cumulative integral sum of pulse amplitudes, dividing the integral sum of pulse amplitudes by the number of pulses to ascertain an average pulse amplitude, and determining average pulse collection efficiency as a function of average pulse amplitude.
Claim 3
Dependent Claim 17 words
The method of claim 1 wherein average pulse collection efficiency is determined from an empirically derived function.
Claim 4
Dependent Claim 26 words
The method of claim 1 wherein average pulse collection efficiency is determined from a mathematically derived function using said liquid scintillation radiation detecting and counting apparatus.
Claim 5
Dependent Claim 20 words
The method of claim 3 wherein said mathematically derived function has parameters that vary between ranges of pulse amplitude limits.
Claim 6
Dependent Claim 66 words
The method of claim 1 wherein said function is a linear function, and wherein the pulse amplitudes of the pulses passed to said pulse amplitude accumulative means are weighted according to a transfer function in arriving at the aforesaid cumulative integral sum of pulse amplitudes, whereby the aforesaid linear function accurately reflects the actual relationship of average pulse collection efficiency to the aforesaid average pulse amplitude.
Claim 7
Dependent Claim 21 words
The method of claim 5 wherein said transfer function has terms that vary as between distinct and different pulse amplitude ranges.
Claim 8
Dependent Claim 22 words
The method of claim 1 further comprising thereafter determining the rate of occurrence of disintegrations based on the average pulse collection efficiency.
Claim 9
Independent Claim 134 words
A method of compensation for quenching liquified radioactive scintillation samples using a liquid scintillation radiation detecting and counting apparatus having photodetecting means, a function generating means, and a data output means, comprising detecting scintillations caused by radioactive events in a liquified radioactive scintillation sample, generating electrical pulses in said photodetecting means in response to scintillations caused by radioactive events in said sample, adding and accumulating the pulses to produce an accumulated integral amplitude sum, dividing said integral amplitude sum by the number of pulses contributing thereto, generating a signal proportional to the resulting quotient representative of an average pulse amplitude, passing said average pulse amplitude signal to a function generating means to produce a signal representative of average pulse collection efficiency, and passing said average pulse collection efficiency signal to said data output means.
Claim 10
Independent Claim 134 words
A method of compensation for quenching liquified radioactive scintillation samples using a liquid scintillation radiation detecting and counting apparatus having photodetecting means, a function generating means, and a data output means, comprising detecting scintillations caused by radioactive events in a liquified radioactive scintillation sample, generating electrical pulses in said photodetecting means in response to scintillations caused by radioactive events in said sample, adding and accumulating the pulses to produce an accumulated integral amplitude sum, dividing said integral amplitude sum by the number of pulses contributing thereto, generating a signal proportional to the resulting quotient representative of an average pulse amplitude, passing said average pulse amplitude signal to a function generating means to produce a signal representative of average pulse collection efficiency, and passing said average pulse collection efficiency signal to said data output means.
Claim 11
Dependent Claim 93 words
In a liquid scintillation radiation detecting and counting device having a scintillation chamber, at least one photodetector in optical communication with said scintillation chamber, the improvement comprising an analog to digital converter operatively connected to said photodetector, a pulse amplitude cumulative register connected to said analog to digital converter, a pulse count cumulative register connected to said analog to digital converter, and dividing means connected to said pulse amplitude cumulative register and to said pulse count cumulative register for dividing cumulated pulse amplitudes by cumulated pulse counts to produce an average pulse amplitude.
Claim 12
Dependent Claim 93 words
In a liquid scintillation radiation detecting and counting device having a scintillation chamber, at least one photodetector in optical communication with said scintillation chamber, the improvement comprising an analog to digital converter operatively connected to said photodetector, a pulse amplitude cumulative register connected to said analog to digital converter, a pulse count cumulative register connected to said analog to digital converter, and dividing means connected to said pulse amplitude cumulative register and to said pulse count cumulative register for dividing cumulated pulse amplitudes by cumulated pulse counts to produce an average pulse amplitude.
Claim 13
Dependent Claim 146 words
In a liquid scintillation radiation detecting and counting device Having a scintillation chamber, at least one photodetector in optical communication with said scintillation chamber, the improvement comprising analog to digital converter means operatively connected to said photodetectors for producing signals representing pulse amplitudes and signals representing pulse counts, an accumulative register connected to said analog to digital converter for storing the total sum of signals representing pulse amplitudes, an accumulative register connected to said analog to digital converter for storing the total sum of signals representing pulse counts, dividing means connected to said accumulative register for pulse amplitudes and to said accumulative register for pulse counts for dividing cumulated pulse amplitudes by cumulated pulse counts to produce an average pulse amplitude, and a function generator operatively connected to said dividing means for applying a function to said average pulse amplitude to arrive at pulse detection efficiency.
Claim 14
Dependent Claim 146 words
In a liquid scintillation radiation detecting and counting device Having a scintillation chamber, at least one photodetector in optical communication with said scintillation chamber, the improvement comprising analog to digital converter means operatively connected to said photodetectors for producing signals representing pulse amplitudes and signals representing pulse counts, an accumulative register connected to said analog to digital converter for storing the total sum of signals representing pulse amplitudes, an accumulative register connected to said analog to digital converter for storing the total sum of signals representing pulse counts, dividing means connected to said accumulative register for pulse amplitudes and to said accumulative register for pulse counts for dividing cumulated pulse amplitudes by cumulated pulse counts to produce an average pulse amplitude, and a function generator operatively connected to said dividing means for applying a function to said average pulse amplitude to arrive at pulse detection efficiency.
Claim 15
Dependent Claim 52 words
The improved device of claim 10 wherein said pulse amplitude analog to digital converter further comprises amplitude sensitive pulse weighting means operative according to a mathematical transfer function with parameters that vary between ranges of pulse amplitude limits, and wherein said function generator applies a linear function to said average pulse amplitude.
Claim 16
Dependent Claim 28 words
The improved device of claim 10 further comprising a disintegration register connected to said function generator for determining the rate of radioactive disintegrations based on pulse detection efficiency.
Claim 17
Dependent Claim 160 words
In a liquid scintillation radiation detecting and coincidence counting device having a scintillation chamber, a plurality of photodetectors in optical communication with said scintillation chamber, and a coincidence detector connected to said photodetectors, the improvement comprising analog to digital converter means operatively connected to said photodetectors and to said coincidence detector for producing signals representing pulse amplitudes and signals representing pulse counts, an accumulative register connected to said analog to digital converter for storing the total sum of signals representing pulse amplitudes, an accumulative register connected to said analog to digital converter for storing the total sum of signals representing pulse counts, dividing means connected to said accumulative register for pulse amplitudes and to said accumulative register for pulse counts for dividing cumulated pulse amplitudes by cumulated pulse counts to produce an average pulse amplitude, and a function generator operatively connected to said dividing means for applying a function to said average pulse amplitude to arrive at pulse detection efficiency.
Claim 18
Dependent Claim 160 words
In a liquid scintillation radiation detecting and coincidence counting device having a scintillation chamber, a plurality of photodetectors in optical communication with said scintillation chamber, and a coincidence detector connected to said photodetectors, the improvement comprising analog to digital converter means operatively connected to said photodetectors and to said coincidence detector for producing signals representing pulse amplitudes and signals representing pulse counts, an accumulative register connected to said analog to digital converter for storing the total sum of signals representing pulse amplitudes, an accumulative register connected to said analog to digital converter for storing the total sum of signals representing pulse counts, dividing means connected to said accumulative register for pulse amplitudes and to said accumulative register for pulse counts for dividing cumulated pulse amplitudes by cumulated pulse counts to produce an average pulse amplitude, and a function generator operatively connected to said dividing means for applying a function to said average pulse amplitude to arrive at pulse detection efficiency.

References Cited (Backward Citations)

US3691386A Cited
US3610928A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-12-17 1977-06-18 1977-12-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-12-17 1981-06-18 1981-12-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-12-17 1985-06-18 1985-12-18 $7700.00 Window Closed / Lapsed

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