TOP > 外国特許検索 > Method, device and program for estimating particle emitted from radioisotope source, method for estimating radiation detector, method and device for calibrating radiation detector, and radioisotope source

Method, device and program for estimating particle emitted from radioisotope source, method for estimating radiation detector, method and device for calibrating radiation detector, and radioisotope source UPDATE

外国特許コード F100002278
整理番号 335US
掲載日 2010年11月29日
出願国 アメリカ合衆国
出願番号 30988808
公報番号 20100274512
公報番号 8178839
出願日 平成20年10月22日(2008.10.22)
公報発行日 平成22年10月28日(2010.10.28)
公報発行日 平成24年5月15日(2012.5.15)
国際出願番号 JP2008069160
国際公開番号 WO2009133639
国際出願日 平成20年10月22日(2008.10.22)
国際公開日 平成21年11月5日(2009.11.5)
優先権データ
  • 2008WO-JP58431 (2008.5.2) WO
  • 2008WO-JP69160 (2008.10.22) WO
発明の名称 (英語) Method, device and program for estimating particle emitted from radioisotope source, method for estimating radiation detector, method and device for calibrating radiation detector, and radioisotope source UPDATE
発明の概要(英語) (US8178839)
When an energy of a particle emitted from a radioisotope source is obtained by a detector, a histogram obtained from a relationship between a difference &Dgr;E between an energy of a particle emitted outside the radioisotope source and an initial energy which the particle possesses at the time of generation and a count is treated as being asymmetric, and an energy distribution (L1) of the particle emitted outside the radioisotope source is obtained, thereby allowing an energy calibration of a radiation detector, absolute quantitation and resolution measurement to be performed with accuracy.
特許請求の範囲(英語) [claim1]
1. An estimation method of a particle emitted from a radioisotope source, the method comprising: obtaining an energy distribution (L1) of the particle emitted outside the radioisotope source by treating a histogram obtained from a relationship between a difference DELTA E between an energy of a particle emitted outside the radioisotope source and an initial energy which the particle possesses at the time of generation and a count as being asymmetric when an energy of a particle emitted from the radioisotope source is obtained by a detector;
estimating an energy deposited while the particle passes through inside the radioisotope source; and
calibrating the energy deposit that has been estimated.
[claim2]
2. The estimation method of the particle emitted from the radioisotope source according to claim 1, wherein the energy deposit in the radioisotope source is estimated by obtaining a travel distance of a particle in the radioisotope source from an occurrence location and an emission direction of the particle within the radioisotope source.
[claim3]
3. The estimation method of the particle emitted from the radioisotope source according to claim 2, wherein the travel distance includes a travel distance from the radioisotope source to an interaction part of a radiation detector.
[claim4]
4. The estimation method of the particle emitted from the radioisotope source according to claim 2, wherein the emission direction of the particle is set isotropically.
[claim5]
5. The estimation method of the particle emitted from the radioisotope source according to claim 1, wherein the particle is a charged particle.
[claim6]
6. The estimation method of the particle emitted from the radioisotope source according to claim 1, wherein the radioisotope source is a thin film radioisotope source (a radioisotope source emitting an internal conversion electron), a beta source or an alpha source.
[claim7]
7. A calibration method of a radiation detector, comprising using a radioisotope source where an energy of a particle is estimated by an estimation method according to claim 1.
[claim8]
8. A radioisotope source comprising being estimated by an estimation method according to claim 1.
[claim9]
9. An estimation method of a particle emitted from a radioisotope source, the method comprising: obtaining an energy distribution (L1) of the particle emitted outside the radioisotope source by treating a histogram obtained from a relationship between a difference DELTA E between an energy of a particle emitted outside the radioisotope source and an initial energy which the particle possesses at the time of generation and a count as being asymmetric when an energy of a particle emitted from the radioisotope source is obtained by a detector; and
estimating an energy deposited while the particle passes through inside the radioisotope source, wherein the energy deposit in the radioisotope source is estimated by obtaining a travel distance of a particle in the radioisotope source from an occurrence location and an emission direction of the particle within the radioisotope source, and
the energy deposit within the radioisotope source is obtained by using an energy distribution function F(Ei) of the particle emitted outside the radioisotope source, which is obtained by estimation, and a response function R(E) shown by the following formula;
(Equation image 6 not included in text)
where E is an energy of the particle, Ei is an initial energy which the particle possesses at the time of generation, and sigma is a standard deviation and indicates a resolution of the detector.
[claim10]
10. An estimation method of a particle emitted from a radioisotope source, the method comprising: obtaining an energy distribution (L1) of the particle emitted outside the radioisotope source by treating a histogram obtained from a relationship between a difference DELTA E between an energy of a particle emitted outside the radioisotope source and an initial energy which the particle possesses at the time of generation and a count as being asymmetric when an energy of a particle emitted from the radioisotope source is obtained by a detector; and
estimating an energy deposited while the particle passes through inside the radioisotope source, wherein the energy deposit in the radioisotope source is estimated by obtaining a travel distance of a particle in the radioisotope source from an occurrence location and an emission direction of the particle within the radioisotope source, and
the energy deposit of the particle within the radioisotope source is obtained by obtaining a distribution function Fk(E) based on an energy deposit within the radioisotope source individually relative to a group of radiations (internal conversion electrons from each shell, beta particles, gamma rays, etc), and estimating an emission rate tau k of each radiation (where k is an index for identifying each radiation contained in the group of radiations and indicates the number of radiations).
[claim11]
11. An estimation method of a particle emitted from a radioisotope source, the method comprising: obtaining an energy distribution (L1) of the particle emitted outside the radioisotope source by treating a histogram obtained from a relationship between a difference DELTA E between an energy of a particle emitted outside the radioisotope source and an initial energy which the particle possesses at the time of generation and a count as being asymmetric when an energy of a particle emitted from the radioisotope source is obtained by a detector;
estimating an energy deposited while the particle passes through inside the radioisotope source; and
calibrating an energy spectrum measured by the radiation detector by the DELTA E; and
obtaining an associated calibrated energy spectrum (L3, L3') such that most probabilities are made in agreement.
[claim12]
12. An estimation method of a radiation detector according to claim 11, further comprising: obtaining an energy spectrum L1a in which a scale of counts of the energy distribution (L1) of the particle obtained is changed so as to be matched with the calibrated energy spectrum (L3, L3').
[claim13]
13. An estimation method of a radiation detector according to claim 12, further comprising obtaining a statistical fluctuation L2 of the radiation detector with use of the calibrated energy spectrum (L3, L3') and the energy spectrum L1a.
[claim14]
14. A computer readable medium storing a computer program for estimating a particle emitted from a radioisotope source, comprising: including a step of obtaining an energy distribution (L1) of the particle emitted outside the radioisotope source by treating a histogram obtained from a relationship between a difference DELTA E between an energy of a particle emitted outside the radioisotope source and an initial energy which the particle possesses at the time of generation and a count as being asymmetric when an energy of a particle emitted from the radioisotope source is obtained by a detector;
estimating an energy deposited while the particle passes through inside the radioisotope source; and
calibrating the energy deposit that has been estimated.
[claim15]
15. The computer readable medium storing a computer program according to claim 14 for estimating and correcting an energy deposited while the particle passes through inside the radioisotope source by writing or rewriting an estimation program on a memory part of an estimation device which includes a processing part for the estimation program and does not estimate an energy deposited while the particle passes through inside the radioisotope source, the estimation program being rewritably written on the memory part and estimating the particle emitted from the radioisotope source based on a method of not estimating an energy deposited while the particle passes through inside the radioisotope source.
[claim16]
16. A calibration device of a radiation detector, comprising being installed with a computer program according to claim 14.
[claim17]
17. A computer readable medium storing a computer program for estimating a particle emitted from a radioisotope source, comprising: including a step of obtaining an energy distribution (L1) of the particle emitted outside the radioisotope source by treating a histogram obtained from a relationship between a difference DELTA E between an energy of a particle emitted outside the radioisotope source and an initial energy which the particle possesses at the time of generation and a count as being asymmetric when an energy of a particle emitted from the radioisotope source is obtained by a detector;
estimating an energy deposited while the particle passes through inside the radioisotope source; and
correcting an estimation in a conventional estimation device which includes another memory part on which an estimation program for estimating the particle emitted from the radioisotope source based on a method of not estimating an energy deposited while the particle passes through inside the radioisotope source, is unrewritably written and a processing part for the estimation program and does not estimate an energy deposited while the particle passes through inside the radioisotope source.
[claim18]
18. An estimation device of a particle emitted from a radioisotope source, comprising: means for obtaining an energy distribution (L1) of the particle emitted outside the radioisotope source by treating a histogram obtained from a relationship between a difference DELTA E between an energy of a particle emitted outside the radioisotope source and an initial energy which the particle possesses at the time of generation and a count as being asymmetric when an energy of a particle emitted from the radioisotope source is obtained by a detector;
means for estimating and calibrating an energy deposited while the particle passes through inside the radioisotope source; and
means for calibrating the energy deposit that has been estimated.
[claim19]
19. A calibration device of a radiation detector, comprising an estimation device according to claim 18.
[claim20]
20. An estimation device of a particle emitted from a radioisotope source, comprising: means for obtaining an energy distribution (L1) of the particle emitted outside the radioisotope source by treating a histogram obtained from a relationship between a difference DELTA E between an energy of a particle emitted outside the radioisotope source and an initial energy which the particle possesses at the time of generation and a count as being asymmetric when an energy of a particle emitted from the radioisotope source is obtained by a detector;
means for estimating and calibrating an energy deposited while the particle passes through inside the radioisotope source;
a conversion table for an energy deposit in accordance with a type and a shape of the radioisotope source; and
a calibration means for calibrating the estimated energy deposit.
  • 発明者/出願人(英語)
  • NAKAMURA HIDEHITO
  • NATIONAL INSTITUTES FOR QUANTUM AND RADIOLOGICAL SCIENCE AND TECHNOLOGY
国際特許分類(IPC)
放医研が保有する特許に、ご関心のある企業等はお問合せ下さい。

PAGE TOP

close
close
close
close
close
close