GB2246235A - Secondary standard ionization chamber for measuring photon radiation - Google Patents
Secondary standard ionization chamber for measuring photon radiation Download PDFInfo
- Publication number
- GB2246235A GB2246235A GB9108139A GB9108139A GB2246235A GB 2246235 A GB2246235 A GB 2246235A GB 9108139 A GB9108139 A GB 9108139A GB 9108139 A GB9108139 A GB 9108139A GB 2246235 A GB2246235 A GB 2246235A
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- compensation
- ionization chamber
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- layer
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- 230000005855 radiation Effects 0.000 title claims abstract description 21
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 9
- 239000004411 aluminium Substances 0.000 claims description 7
- 229910052782 aluminium Inorganic materials 0.000 claims description 7
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 7
- 150000001875 compounds Chemical class 0.000 claims description 7
- 229910052799 carbon Inorganic materials 0.000 claims description 6
- 229910052788 barium Inorganic materials 0.000 claims description 5
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 claims description 5
- 239000003822 epoxy resin Substances 0.000 claims description 5
- 150000002500 ions Chemical class 0.000 claims description 5
- 229920000647 polyepoxide Polymers 0.000 claims description 5
- 239000011248 coating agent Substances 0.000 claims description 4
- 238000000576 coating method Methods 0.000 claims description 4
- 230000000149 penetrating effect Effects 0.000 claims description 4
- 229920005989 resin Polymers 0.000 claims description 4
- 239000011347 resin Substances 0.000 claims description 4
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 3
- 239000000654 additive Substances 0.000 claims description 3
- 229910052790 beryllium Inorganic materials 0.000 claims description 3
- ATBAMAFKBVZNFJ-UHFFFAOYSA-N beryllium atom Chemical compound [Be] ATBAMAFKBVZNFJ-UHFFFAOYSA-N 0.000 claims description 3
- 229910052796 boron Inorganic materials 0.000 claims description 3
- 239000010439 graphite Substances 0.000 claims description 3
- 229910002804 graphite Inorganic materials 0.000 claims description 3
- 239000000203 mixture Substances 0.000 claims description 3
- 238000005507 spraying Methods 0.000 claims description 3
- 238000010521 absorption reaction Methods 0.000 claims description 2
- 229910052797 bismuth Inorganic materials 0.000 claims description 2
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 claims description 2
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 claims description 2
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims description 2
- 239000000292 calcium oxide Substances 0.000 claims description 2
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 230000000694 effects Effects 0.000 claims description 2
- 229910052742 iron Inorganic materials 0.000 claims description 2
- 239000000463 material Substances 0.000 claims description 2
- 229910052759 nickel Inorganic materials 0.000 claims description 2
- 229920001187 thermosetting polymer Polymers 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 2
- 229910052725 zinc Inorganic materials 0.000 claims description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims 3
- 238000001704 evaporation Methods 0.000 claims 2
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims 1
- 239000005977 Ethylene Substances 0.000 claims 1
- 229930182556 Polyacetal Natural products 0.000 claims 1
- 239000004698 Polyethylene Substances 0.000 claims 1
- 230000000996 additive effect Effects 0.000 claims 1
- LNEPOXFFQSENCJ-UHFFFAOYSA-N haloperidol Chemical compound C1CC(O)(C=2C=CC(Cl)=CC=2)CCN1CCCC(=O)C1=CC=C(F)C=C1 LNEPOXFFQSENCJ-UHFFFAOYSA-N 0.000 claims 1
- 238000000034 method Methods 0.000 claims 1
- -1 polyethylene Polymers 0.000 claims 1
- 229920000573 polyethylene Polymers 0.000 claims 1
- 229920006324 polyoxymethylene Polymers 0.000 claims 1
- 239000000843 powder Substances 0.000 claims 1
- 238000004544 sputter deposition Methods 0.000 claims 1
- 241000206607 Porphyra umbilicalis Species 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 229940037003 alum Drugs 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- CNJLMVZFWLNOEP-UHFFFAOYSA-N 4,7,7-trimethylbicyclo[4.1.0]heptan-5-one Chemical compound O=C1C(C)CCC2C(C)(C)C12 CNJLMVZFWLNOEP-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 239000004593 Epoxy Substances 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005865 ionizing radiation Effects 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 229940058401 polytetrafluoroethylene Drugs 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J47/00—Tubes for determining the presence, intensity, density or energy of radiation or particles
- H01J47/02—Ionisation chambers
- H01J47/022—Calibration thereof
Landscapes
- Measurement Of Radiation (AREA)
Abstract
The invention relates to a secondary standard ionization chamber for the precise measuring of photon radiation with a chamber wall substantially closed on all sides, an outer electrode in the area of the chamber wall and an inner electrode. The inside of the wall (1) of the chamber (7), is provided with three compensation layers (3, 4, 5), the individual compensation layers (3, 4, 5) containing elements of different atomic numbers such that the outer layers 3, 5 have elements of atomic number higher than air while the middle layer 4 includes an element of atomic number lower than that of air. This achieves the most precise connection between the ion dose and the measurable variables prescribed according to ICRU in respect of environment equivalent dose, in particular indpendently of the energy distribution of the respective radiation. <IMAGE>
Description
:2 2 m4 G-1,:2 E5 -I- SECONDARY STANDARD IONIZATION CHAM?ER FOR MEASURING
PHOTON RADIATION The invenzion relates to a secondary standard ionization chamber for the measurement of photon radiation by means of e.g. a spherical chamber wall substantially closed on all sides and optionally provided with an air inlet orifice, having an outer electrode on or adjaomt the chamber wall and an inner electrode.
The introduction of the international unit system SI made it necessary to use new measurable variables for the dosimeters of ionizing radiation. These measurable variables were established by ICRU.in the report ICRU-39 and are now being introduced into legislation relating to measures and
15to radiation protection.
It is the object of the invention to provide special secondary standard ionization chambers serving only for measuring photon radiation whose energy dependence for the measurable variables "environment equivalent dose H(10)" 20and "direction equivalent dose H'(10) and H'(0.07)" is optimized. This is to allow a direct calibration of local and personal dosimeters in the new measurable variables and the practical introduction of the new measurable variables accordina to ICRU.
-5 In particular, secondary standard ionization chambers for the dose capacity range of 0.1 pSv/h to 1 Sv/h whose energy dependence for photon radiation in the range between KeV and 11.3 MeV is optimized for the direct measuring of to be provided.
H (10), H' (1, 0) and H (00. 7) are t These objects are achieved according to the --nvention Jn a dosimeter or an ionization chamber of the --Ype initially mentioned bv providing, in order to obtain 7' h e most exact possible connection between the ion dose measured and the desired measurable variables according to ICRU, environment i5equivalent dose H(10) and direction equivalent dose H'(1-0) ana (H'(0.07), in particular indepencently of the energy distritution of the respective radiation, at least I optionally - 1hree enercy compensation lavers, Of multilaver composition, on the inside of the wall of the chamber, in particular completely covering the same, the -First compensation layer on the chamber wall, which is over-sensitive as compared to air in --egard to the seconcary electron emission,containing an element of higher effective atomic number as compared to air, preferably an atomic number equal to or higher than barium, in particular lead and/or bismuth, of a total surface density of 0.1 to 5 MgJCM2, preferably 0.3 to 3 mg/cm2, of the element(s), a josecond, middle compensation layer being applied to this outer, first compensation layer and containing, in order to achieve the desired absorption and f41Lt _ ar effect, at least one element with an atomic number lower than that of air, preferat'-v carbon, in particular in the form of areoni-te 7 a and/or synthetic resins and/or boron and/or beryllium. of total surface density of 5 to 15 ma/'cm2, preferably 9 --o mg/Cj2 of --he element(s), and a comoensation layer beino appliec onto compensation 'Layer and containing, in order t slionrly element with an I ower than that elements -"-, '-1c oensi:Y 0.2 )r,o_f the element(s). According -,C a-comic number hiaher --han that if tarium. nre4--erabl-v at least zh O'Z 1 U ' N i ' II.I '. - - o 21 MC!cm,, Dre--Ferab'.,, 0.5 -:;G e --iven-c- on h e sucs--anz---=-, v a nz th e possibility o f c, J. r e c t -Ieasu-r-"ng measurable vari--bles accordinc -:; o I C S U ' J-depenoen-c-2 jose r a c to I_.ow -hus resces --n -me presc---4,-,e--;valen Particular ---le environmenz eQu -Ozne spectral enercy distribution photon measurIng instruments known u possible to -,ieasure the ion dose, buz the rad-'az--on Lo be known in order to be able --o convert 0 the has t ICRU measurable variables according tv m. e a n s i nenergy -dependent conversion factors as a converst on to 7-ne new measuraole variables has not been o-.her5jise.
1 1; a-cion. %,.L has n ew a thira, -nner t h i S m i c d 1 e 0 _= -, -- ' n. a laver Lessz _Ine J:
air anc J:
one 3_ n e 1 i j i 1 i I 1 i i i j i i 1 i5evaporating, t o the as the (10) and t o the wall ' f ollows and the variables souttering, preferably compounds thin coating According to the invention, it may also be provided the elements anjor their compounds to be aDpliea powaer distributed in thermosetting resins, preferanly resins. The carnon contained in the resins must be surface censit layer and is total surface eMP12yeo in p ins-catea a The secondary standard ionization chamber according invention now permits a direct measurement measurable variable directly indicates the secondary s invention, possesses an H (10) or H tandard ionization chamber according due to the configuration of its chamber energy dependence which very exactly the predetermined connection between the ion dose photon equivalent dose and the new measurable according to ICRU.
The elements employed in the compensation layers conveniently contained therein in elementary form or in form of compounds, in pulverized form or the applied to zhem in particular oxides, elements and/or their the form of a spraying or the like 20into consideration for the tonal carnon in the middle compensatisn zhe preceterminea values of the if the invicual elements are ii is convenierz to aoply the in 2 to 30 oartial layers corresoonas are the in are b y for 3S a epoxy taKen Me in y of incluceo:ensizy.
uiverizec f:rm, Mounts 0 the z: 20 the outer and middle comoensezi:n i. 5 25elements distributed Mg/CM2, preferably mg/cm2, of epoxy resin, in layers ana in 3.2 to 2 mg/cmz, preferably mg/cm2, of epoxy resin in the in a particular emoodiment of the invention, 30provided for at least one of the compensation composed of partial layers, with these containing identical elements, optionally surface density or different elements respective comzensazion layer, although P5surface densities of the elements to that of i. 5 inner compensation layer. it may te t 0 Z clayers layers partial of possible the sum in the respective the predeterminec total surface density of the respective compensation layer composed of these partial layers. By the sub-division of the individual compensation layers, it is possible under certain 7 the circumstances to achieve an even better adjustment of measuring characteristics to the measuring characeristics predetermined by ICRU.
Further preferred embodiments of the invention are disclosed in the following description of the drawing and in the appended claims.
0 The invention is explained in the following on the basis of an exemplary embodiment.
Fig. 1 shows a sectional view of a secondary ionization chamber according to the invention; Fig. 2 represents a detailed view thereof; Fig. 3 shows an embodiment c: 11h sectional view; and Fig. d represents a diagram.
The secondary standard ionization chamb standard con.Densaton layers J n -7 1 er i represented 1 in sectional view in Fig. 1 comorises a spherical chamoe-r 3 201all 1 on whose -Jnside compensation layers 'I ' 5 a n a a n snape other --nan spherical, such as Such an, in oartIcular c;--ane-cer c-; e. c. aocuz 3 0 cent -:re--e t iv adecuate 4for measur,no the natural envi-ronment sens rad-Jaz:.on. I n -t-hi s emDo(i.Lrnent, the inner e-l=-c-.rc-.e consIsts -n-co.,jh--ci projects a small a--jm--;ni-um u b e of a sDhere 15 J rom the too s-4z:e of the chamber 16 4. 7 as a Cuioe tuDe cube est emitter 19. Since the guide t 1-6 must not e f f e c 30an eectr-;c connection with the inner elect.roce 15 3 - - electrically shielded by the shield tube 17 and thus exerts no influence on the electric f-Leld 1_; nes in zhe inzerior f the chamber 7. The test emitter 11,9 is introoucea -nto -.he guide tuDe:3y means of --he lua II end remains -4ns-Jide of --ne z5clar,ioer only -.ur--n- test. messurina.
t: - i I i i cyl-nd----:ca';. cr --he -'-:e.
cnamoer can -.eve a m,easl;-- na i I p i I I i i 2 1 1 - 5 For forming the compensation layer IS is outer electrode, conveniently formed electrically tive and/or a thin electrically conductive layer conduct 6, 4r for instance of graphite, aluminium or the like, is formed, for instance evaporated on or sprayed on, on the innermost compensation layer, by which the penetrating radiation to be measured remains virtually unaffected as compared to the compensation layers and virtually no secondary electrons are generated therein by the penetrating radiation. The conductive layer 6 forming the outer electrode can be formed' as an aluminium layer with a surface density density of no more then 0.05 mg/cmz of Al. standard ionization chamber 7 is provided 4- 4 1-ssue or water equivalent chamber wall 1 of a t most consisting of at leas- 81. percenz i 5 3 cm a- I- L, ially polyace-cal, in a basic substance, substanti Jn a mixture of up to 20 percent by polytetrafluoro ethylene to which optionall' preferably calcium oxide, alum carbon are ear.nixed, the chamber E percent by weJghz at most of he chamber wall may cD---onal-lY 2 snows a secz--onal n 'n cers'. It shows aPD1-i.-ci to the inner surface ou-.er e-lec--rcce 6 4-s aQP-L-4--a 1 layer 5 in the -form of an ele unless the --nner compensation laver 55 and.,,sed as an outer electrode.
-:e elements barium and/cr 2-eac and/cr b,-smuth are acvanzageously used for the first, outermost compensation layer 3. in -:,1-le m4Lcc-l-compensation layer 1, --n --ar-.,cu--ar carbon in the form of craphite is employed. The caron usec -'n -.he emneac--;nQ mass (usualy synzhec -es4n) cr -aphJ-e or boron or beryllium must be taken --nTo - 9. consideration in the same way as the carbon (,grepnize) used or coating The secondary,4 J t- h a n air, -hickness of by weight of partcular .je c:hz of y additives, inium oxide, alum:_nium anol'or wall 1 aluminium as an -ncc-z-4ve; cons.;s-- of 2o-,,je-:;hy--ene.
V r-, -r- - n c z 0 t i e 2 e-?- a 1 A ,i a c c - t h e 0 f to tile c-- r t -cal co,-,.Densa-c--2n levers 3 -1 5 h e chamber val' 1. The e r m c s z cor.ze-.ss-.--on y c c n a u cz e 'ayer, s formea conduct--ve in the layer material of the middle compensation layer. The inner compensation layer 5 conveniently consists of at least one of the elements aluminium, magnesium, iron, copper, nickel or zinc, other elements with an atomic number lower than the one of barium but higher than the one of air also being suitable for use. It was found that at appropriate selection of the total surface density of the individual elements in the individual layers, a response capacity of the secondary standard ionization chamber 7 is achieved which completely complies with the prescriptions of ICRU and very precisely corresponds to the predetermined connection between radiation engergy and environment equivalent dose.
Fig. 4 shows the relative response capacity a(E)a(CS), i. e. the response capacity as a function of energy úa(E)2 based on the response capacity at an energy of 137Cs gamma radiation (0.661 MeV) fa(Cs).7, of a secondary standard ionization chamber according to the invention plotted above the radiation energy E. The full line shows the set value curve predetermined by ICRU representing the connection between the environment equivalent dose and photon equivalent dose or ion dose. Curves for the relative response capacity of two secondary standard ionization chambers according to the invention are represented by means of circles and squares; it was found that deviations from the predetermined set value curve of no more than 1+ 2 percent can be achieved, which means that a measuring device was provided which measures absolute values of environment equivalent dose independently of the spectrum of the 30energy radiation to be examined in the predetermined SI units.
It is understood that the entire measuring device could also be formed for directional operation for measuring the (directionally operated) direction equivalenz dose.
1 i i 1 i i 1 Z11
Claims (15)
1. A secondary ionization chamber for the measuring of photon radiation, having a chamber wall, an outer electrode on or adjacent the chamber wall and an inner electrode, and at least three energy compensation layers (3, 4,5) on or adjacent the inside of the wall of the chamber; the f irst compensation layer being over-sensitive as compared to air relative to the secondary electron emission, containing at least one element of effective atomic number relatively higher than air, a second middle compensation layer on the outer first compensation layer and containing at least one element with an atomic number lower than that of air, and a third, inner compensation layer on the middle compensation layer and containing at least one element with an atomic number higher than that of air.
8
2. A secondary standard ionization chamber for the precise measuring of photon radiation having an in particular spherical chamber wall substantially closed on all sides and optionally provided with an air inlet orifice, an outer electrode in the area of the chamber well and an inner electrode, characterized in that for forming the most exact possible connection between the ion dose measured and the desired measurable variables according to ICRU of the direction particular independently of the energy distribution of the respective radiation, at least three energy compensation layers 1C)environment equivalent dose C(10) and the equivalent dose M(10) and W(O.07), in (3,4,5), optionally composed of multilayers, are applied to 15the inside of the wall (1) of the chamber (7), in particular completely covering the same, the first compensation layer (3) on the chamber wall (1), which is over-sensitive as compared to air in regard to the secondary electron emission, containing at least one element of 20higher effective atomic number preferably an atomic number equal as compared to air, to or higher than that of in particular lead and/or bismuth, of a total density of 0.1 to 55 mg/cm2, preferably 0.3 to 3 second barium, surface M9/CM2, 25layer (4) being applied to this outer, first layer (3) ana containing, in order to achieve the at least one element E air, at 0 graphite of the element(s) absorption ano filter effect atomic number lower than -Lh in particular in the form of 3gesins and/or boron and/or beryllium, density of 555 to 15 molcm2, preferably the element(s), and a third, being applied to this middle compensation layer containino, in order to form a layer slightly 3gDver-sensitive as compared to air, at least one element with a middle compensation compensation desired with an carbon, synthetic surface Of (5) and preferably and/or of a total CI to 14 Mg/CM21 Jnner compensation layer 1.
-, 1 R I 1 1 i j j j 1 1 1 i 1 '1: ' C- 9 an atomic number higher then that of air and lower than that of barium, preferably one of the elements Al, M9, Fe, Cu, Ni, Zn, with a total surface density of 0.2 to 2 M9/CM2, preferably 0.5 to 1.5 M9/CM2, of the element(s).
3. The ionization chamber ac=cling to-claim 1 or 2, wherein the elements employed in the compensation layers - -..-. are present in elementary form or in the form of compounds, in particular oxides.
4- The ionization chamber according to claim 1, 2 or 3, %tieredn" the elements and/or their compounds are contained in the compensation layers (3,4,5) in pulverized form.
-5-The ionization chamber according to any one of the claims I to wherein the elements and/or their compounds are applied in the form of a thin coating by means of evaporating, sputtering, spraying or the like.
6. The ionization chamber according to any one of the claims I to 5., wherein the elements and/or their compounds are applied in thermosetting resins, preferably epoxy resins, distributed as powders as compensation layers (3,4,5).
7- The ionization chamber according to any one of the claims 1 to 6, wherein the indicated amounts of the elements in the outer and middle compensation layers (3,4) are applied distributed in 2 to 30 Mg/CM2 preferably 5 to 20 30mg/cm2,of epoxy resin, and in the inner compensation layer (5) in 0.2 to 2 mg/cm2, preferably 0.5 to 1.5 Mg/CM2, 6 of epoxy resin.
8- The ionization chamber according to any one of the claims 351 to 7, wherein for forming the outer electrode, the innermost compensation layer (5) is formed electrically conductive or a thin, electrically conductive layer (6),for 1 c instance of graphite or aluminium or the like, is formed by evaporating or spraying on the innermost compensation layer (5), by which the penetrating radiation remains virtually unaffected as compared to the compensation layers and in which virtually no secondary electrons are generated bythe penetrating radiation.
-
9. The ionization chamber according to claim8, wherein the conductive layer (6) forming the outer electrode is formed joas an aliminium layer with a surface density or coating density of 0.05 m91cm2 at most.
10. The- ionization chamber according to any one of the claims 1 to 9, wherein an air, tissue or water equivalent chamber 15wall (1) of a thickness of 3 mm at most is provided and consists of at least 85 percent by weight of a basic material substantially containing polyacetal, in particular a mixture of up to 20 percent by weight of polytetrafluaro ethylene to which optionally additives, 20preferably calcium oxide, aluminium oxide, aluminium andlor carbon are admixed.
The ionization chamber according to claim 10, wherein
11.
the chamber wall (1) contains 10 percent by weight at most 2150f aluminium as an additive.
12. The ionization chamber according to any one ofthe claims 1 -o 11 wherein the chamber wall (1) consists of polyethylene.
The ionization chamber according t 0 any one o f the
13.
claims 1 to 12, wherein at least one of t h e compensation layers (3, 4, 5) is composed of iarzial layers (3,; 5, 'j") 1 these partial layers (3, 3; 5, 5") containing identidal 35elements i n preferably different surface density or different elements possible in the respective compensation i 1 i f i 1 1 1 11 an with layer in equal or different surface density, althoug the sum of the surface densities of the elements In the respective partial layers (3,3"; corresoona-ina ta the predetermined total surface aensity of -.he resoective compensation layers (3,4,5) comDosed of tnese par7.ial layers.
14. The ionization chamoer accordina to any one of zhe claims 1 to 13, wherein the chamber is fil"led with air.
15. A secondary ionization chamber for measuring photon radiation substantially as herein described with reference to and as illustrated in the accomoanying drawings.
Published 1992 at The Patent office. Concept House. Cardiff Road. Newport. Gwent NP9 I RH Further copies mav be obtained froin Sales Branch. Unit 6. Nine Mile Point- OA-imfelinfach. Cross Keys. Newporl. NPI 7HZ. Printed by Multiplex techniques lid St Mar. Cray- Kent.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT88690A AT394456B (en) | 1990-04-17 | 1990-04-17 | SECOND IONIZATION CHAMBER FOR MEASURING PHOTON RADIATION |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB9108139D0 GB9108139D0 (en) | 1991-06-05 |
| GB2246235A true GB2246235A (en) | 1992-01-22 |
| GB2246235B GB2246235B (en) | 1994-08-03 |
Family
ID=3502089
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9108139A Expired - Fee Related GB2246235B (en) | 1990-04-17 | 1991-04-17 | Secondary standard ionization chamber for measuring photon radiation |
Country Status (3)
| Country | Link |
|---|---|
| AT (1) | AT394456B (en) |
| DE (1) | DE4112086C2 (en) |
| GB (1) | GB2246235B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102955166A (en) * | 2011-08-19 | 2013-03-06 | 中国辐射防护研究院 | Method for ionization chamber X, gamma energy response compensation by using titanium material |
| CN102955165A (en) * | 2011-08-19 | 2013-03-06 | 中国辐射防护研究院 | Method for compensating X and gamma energy response of ionization chamber by aluminum material |
| CN103311086A (en) * | 2012-03-15 | 2013-09-18 | 中国原子能科学研究院 | Multi-layer cavity ionization chamber |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104109042B (en) * | 2014-08-13 | 2016-08-24 | 广西华科达科技发展有限公司 | The production method of illite/smectite mixed layer clay mine tailing compression Nutrition Soil |
| CN109459780B (en) * | 2018-12-26 | 2024-09-06 | 中国原子能科学研究院 | Flat ionization chamber for pulse X-ray and gamma-ray dose measurement |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3898464A (en) * | 1972-07-07 | 1975-08-05 | Vln Corp | Ion chamber instrument |
| EP0030929A1 (en) * | 1979-03-12 | 1981-06-24 | Österreichisches Forschungszentrum Seibersdorf Ges.m.b.H. | Ionisation chamber usable as secondary standard for measuring the energy dose of X- and gamma radiation |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT89856B (en) * | 1920-01-02 | 1922-11-10 | Veifa Werke Vereinigte Elektro | Device for the examination of X-rays and other ionizing rays. |
| DE1221367B (en) * | 1960-07-18 | 1966-07-21 | Dr Harald F H Warrikhoff | Detector for direct or indirect ionizing radiation |
| DE1156514B (en) * | 1961-06-07 | 1963-10-31 | Vakutronik Veb | Sensitive energy and direction-independent ionization chamber working with gas amplification in the proportional range |
| US3249755A (en) * | 1962-08-29 | 1966-05-03 | Bendix Corp | Pocket dosimeter using a phosphor and photocathode |
| DE2125120A1 (en) * | 1971-05-21 | 1972-11-30 | Licentia Gmbh | Dose meter-detecting high speed neutrons - using a lead polyethylene and metal alloy laminated emitter |
| FR2431138A1 (en) * | 1978-07-12 | 1980-02-08 | Commissariat Energie Atomique | METHOD FOR AUTOMATICALLY READING THE IRRADIATION DOSE OF A PORTABLE DOSIMETER WITH IONIZATION CHAMBER AND DEVICE IMPLEMENTING THIS METHOD |
| DE2854927A1 (en) * | 1978-12-20 | 1980-06-26 | Frieseke & Hoepfner Gmbh | Ionisation chamber dosimeter - with inner and outer capacitor electrodes insulated by beads |
| AT375472B (en) * | 1982-06-04 | 1984-08-10 | Oesterr Forsch Seibersdorf | SECOND STANDARD IONIZATION CHAMBER, ESPECIALLY FOR MEASURING THE ENERGY DOSE |
-
1990
- 1990-04-17 AT AT88690A patent/AT394456B/en not_active IP Right Cessation
-
1991
- 1991-04-12 DE DE19914112086 patent/DE4112086C2/en not_active Expired - Fee Related
- 1991-04-17 GB GB9108139A patent/GB2246235B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3898464A (en) * | 1972-07-07 | 1975-08-05 | Vln Corp | Ion chamber instrument |
| EP0030929A1 (en) * | 1979-03-12 | 1981-06-24 | Österreichisches Forschungszentrum Seibersdorf Ges.m.b.H. | Ionisation chamber usable as secondary standard for measuring the energy dose of X- and gamma radiation |
Non-Patent Citations (1)
| Title |
|---|
| Radiation Protection Dosimetry.Vol.7,no.1-4 1984 Duftschmid Ionisation chamber system pages 191-193. * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102955166A (en) * | 2011-08-19 | 2013-03-06 | 中国辐射防护研究院 | Method for ionization chamber X, gamma energy response compensation by using titanium material |
| CN102955165A (en) * | 2011-08-19 | 2013-03-06 | 中国辐射防护研究院 | Method for compensating X and gamma energy response of ionization chamber by aluminum material |
| CN103311086A (en) * | 2012-03-15 | 2013-09-18 | 中国原子能科学研究院 | Multi-layer cavity ionization chamber |
| CN103311086B (en) * | 2012-03-15 | 2016-03-30 | 中国原子能科学研究院 | Multi-layer cavity ionization chamber |
Also Published As
| Publication number | Publication date |
|---|---|
| DE4112086C2 (en) | 1997-02-27 |
| AT394456B (en) | 1992-04-10 |
| GB2246235B (en) | 1994-08-03 |
| GB9108139D0 (en) | 1991-06-05 |
| DE4112086A1 (en) | 1991-10-24 |
| ATA88690A (en) | 1991-09-15 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 711B | Application made for correction of error (sect. 117/77) | ||
| 711H | Case decided by the comptr. ** correction allowed (sect. 117/1977) | ||
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19970417 |