COMPOSITE SCINTILLATORS AS NEW TYPE OF A

SCINTILLATION MATERIAL

N.L.Karavaeva∗

Institute for Scintillation Materials, National Academy of Sciences of Ukraine,

60 Lenin Avenue, 61001, Kharkov, Ukraine

(Received May 16, 2014)

For radioecological tasks, we have developed a new type of scintillation materials – composite scintillators, consisting

of dielectric gel as a base into which granules of scintillating substances were introduced. It has been shown that such

material can be created both on the basis of organic and inorganic granules. In the first case, efficient fast neutron

detectors can be created, with neutron discrimination on the background of gamma-radiation close to organic single

crystals. In the second case, efficient detectors of thermal neutrons could be developed, with variation of the granule

size allowing substantial reduction of the effects of background radiation. Separate fragments of the scintillator can be

linked together, creating endless planes. A possibility of using bases with higher radiation hardness as compared with

standard scintillator bases, as well as using any scintillating substance for granules allows thinking about possible

application of such technological approach not only for radioecological tasks (ultra-low fluxes), but also in high energy

physics.

PACS: 29.40.Mc, 81.05.Zx

1. INTRODUCTION

Earlier, we proposed a technology for preparation ofnew type of organic scintillation materials for efficientdetection of fast and thermal neutrons. This allowedcreation of detectors without limitations imposed onarea and shape of the input window [1, 2]. The ob-tained scintillation materials and detectors on theirbase are characterized by high universality, simplic-ity of their use and possibility of their application forwide spectrum of problems related to detection andidentification of ionizing radiations. However, notall possibilities of this technological approach havebeen used. Thus, with a new generation of acceler-ators, irradiation of detectors in these installationsbecame much stronger. Unique possibilities of com-posite scintillators make it promising to create scin-tillation systems with high radiation stability. In thispaper, we present our analysis of possible applicationsof composite scintillators.

2. APPLICATION OF COMPOSITESCINTILLATORS

2.1. Fast neutron detectors

In a hydrogen-containing organic material, fast neu-trons generate recoil protons, with their maximumenergy equal the energy of neutrons. Thus, organicscintillators and detectors on their base can be usedfor spectroscopy of fast neutrons [3].

We have developed composite scintillators that,like organic single crystals, were able to discern parti-cles by the shape of scintillation pulse. The schemes

used for separation between the radiation to be de-tected and the background were presented in ourprevious works [4, 5, 6, 7]. These schemes allow de-termining the spectra of recoil protons. Appropriateprocessing by numerical differentiation allows obtain-ing, after reconstruction, of the Pu-Be source neutronspectrum. As an example, Fig.1 shows the obtainedneutron spectrum of Pu-Be source for a compositescintillator based on stilbene granules with linear di-mensions of granules L from 1.7 to 2.0 mm. The scin-tillator dimensions: diameter 30 mm, height 20 mm.

100 200 300 400 500 600 700 800 9000

500

1000

1500

2000

2500

Num

ber o

f det

ecte

d ne

utro

ns

Channel Number

3

987

65

432

1

Fig.1. Reconstructed neutron spectrum of 239Pu-Besource for composite scintillator on the basis of stil-bene granules with linear dimensions of granules Lfrom 1.7 to 2.0 mm

In Fig.1, peaks 1 – 9 correspond to energies 3.1; 4.2;4.9; 6.4; 6.7; 7.3; 7.9; 8.6 and 9.7 MeV of neutronsemitted by 239Pu-Be source [8].

∗Corresponding author E-mail address: karavaeva77@rambler.ru

ISSN 1562-6016. PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY, 2014, N5 (93).Series: Nuclear Physics Investigations (63), p.91-97.

91

When the granule size is optimal, we can obtainspectra identical to those with a single crystal; withgrain size smaller than or comparable to the path ofrecoil protons, the spectrum will be smeared.

One should note that detection selectivity withour samples was confirmed by studies of our col-leagues in Poland [9], as well as in China and SouthKorea [10].

2.2. Thermal neutron detectors

The next step in the use of broad possibilities offeredby our technological approach is creation of compos-ite scintillators for detection of thermal neutrons onthe basis of Ce:GSO and Ce:GPS.

These substances were chosen because of theiruniquely high cross-section of thermal neutron radi-ation capture by gadolinium nuclides 155Gd, 157Gd,alongside with high content of these nuclides in thenatural raw material. This allows using a naturalmixture of gadolinium nuclides without its additionalenrichment. As a result of thermal neutron capture,gadolinium emits conversion electrons, as well as pho-tons of characteristic X-ray and gamma radiation.When the edge effect is small, gadolinium-based scin-tillators should exhibit a characteristic peak of 33 keVenergy, alongside with another peak at 77 keV, whichis the sum of the 33 keV peak of conversion electronsand 44 keV – of X-ray radiation [11].

To obtain thermal neutrons, we used a calibratedparaffin sphere with a 239Pu-Be source inside. Theyield of thermal neutrons was 9% of the total fast neu-tron flux (105 neutrons/s). The thermal neutron peakwas identified by the ”cadmium difference” method.To reduce the number of gamma-radiation photon de-tection events, a lead shield of 2.5 cm thickness wasused.

The efficiency of thermal neutron detection wasestimated as follows:

εth =NΣ

t · Ffast · ηth · S4πR2

× 100%, (1)

where NΣ is the number of events of thermal neutrondetection, t is the time of accumulation of the events(spectrum); Ffast is the number of fast neutron emit-ted by the source per second, ηth=0,09 is the numberof neutrons moderated in the paraffin sphere to ther-mal energy per one fast neutron, S is the thermalneutron detector area, R is the distance between thesource and the detector.

The value εγ (Fig.6) was calculated as

εγ = 1− exp(−µρρξd), (2)

where µρ is the mass attenuation coefficient of X-rayradiation [12], ρ is the density, ξ is the volume frac-tion of crystalline granules for Ce:GSO and Ce:GPS(see Chapter 3.3)), d is the scintillator thickness. Itwas assumed that d was equal to the average grainsize in the given fraction. The coefficient ξ accountedfor the fact that in the composite scintillator (asdistinct from single crystals) the space between the

scintillating substance (granules) was filled by non-scintillating gel. The calculations were carried out forgamma-radiation energies of 30 keV, 60 keV, 80 keV,150 keV, 600 keV, and 8 MeV.

Fig.2 shows, as an example, the calculation re-sults for thermal neutron detection efficiency εth fora set of composite scintillators Ce:GSO. Calculationswere carried out separately for each of three energyranges. Unfilled signs in Fig.3 show εth values forCe:GSO single crystals of 0.39 mm thickness. Datafor the conversion electron detection range are notedby squares, for the 77 keV peak – triangles, and fortheir total signal – circles. The calculated curvesof gamma-radiation detection efficiency εγ are pre-sented as solid lines.

We have compared the values of thermal neutrondetection efficiency calculated by formula (1) usingthe obtained experimental data (internal counting)and detection efficiency of external gamma-radiationphotons εγ , which were calculated by formula (2).

0,01 0,1 10,0

0,2

0,4

0,6

0,8

1,0

0,01 0,1 1

0,0

0,2

0,4

0,6

0,8

1,0

Detector Thickness (mm)

65

4

3

2

Effic

ienc

y of

neu

tron

dete

ctio

n e th

1 ® Eg = 30 keV2 ® Eg = 60 keV3 ® Eg = 80 keV4 ® Eg = 150 keV5 ® Eg = 600 keV6 ® Eg = 8000 keV

Effic

ienc

y of

gam

mf d

etec

tion

e g

1

20-120 keV56-120 keV,20-55 keV,

Fig.2. Thermal neutron detection efficiency εth fora set of composite scintillators Ce:GSO (signs) andcalculated detection efficiency εγ of gamma-radiationof energy Eγ (lines) as function of detector thicknessd

As it can be seen from Fig.2, the detection efficiencyof 33 keV conversion electrons (squares) is weakly de-pendent upon the scintillator thickness. This resultsbecomes clear if we take into account that the freepath of 33 keV electrons in a given scintillation mate-rial is approximately equal to 0.002 mm [13]. There-fore, a single-layer composite gadolinium-containingscintillator with average Ce:GSO or Ce:GPS granulesize above 0.002 mm is already an efficient selectivedetector of conversion electrons of 33 keV energy.The detection efficiency of external gamma-radiationphotons in this case becomes lower as compared withdetection efficiency of secondary radiations emerginginside the granules, and substantial passive protec-tion from external gamma-radiation photons becomesredundant.

2.3. Combined neutron detectors

Using the broad possibilities of the proposed techno-logical approach, we have developed new combined

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composite detectors for separate detection of fastand thermal neutrons on the background of gamma-radiation. These detectors are composed of an or-ganic composite scintillator that detects fast neu-trons and a single-layer inorganic composite scintilla-tor that detects thermal neutrons [5].

2.4. Detectors of alpha particles

The proposed technological approach to prepara-tion of composite scintillation materials can also beused for those materials which cannot be grown fromthe melt as bulky crystals. Fig.3 shows amplitudescintillation spectra of a single-layer composite scin-tillator on the basis of 1,4-diphenyl-1,3-butadieneexcited by alpha-particles of different energies.

100 200 300 400 5000

200

400

600

800

1000

1200

1400

2000 4000 6000 8000 10000Number of Photons

45 6

7

32

Alpha EnergiesEa (MeV)

1 0.65 2 1.443 2.164 2.715 3.296 3.877 4.43

1,4-diphenyl-2,3-butadiene Single-layer composite detector (thin crystalline plates)

Num

ber o

f pul

ses

Channel Number

1

Fig.3. Amplitude scintillation spectra of single-layer

composite scintillator on the basis of 1,4-diphenyl-1,3-

butadiene in detection of alpha-particles of energies

0.65 MeV, 1.44 MeV, 2.16 MeV, 2.71 MeV, 3.29 MeV,

3.87 MeV and 4.43 MeV (239Pu)

Alpha-particles of different energies were ob-tained by their moderation in air. The energyof alpha-particles passed through the air layerof thickness h was determined in the followingway. Knowing the alpha-particle path in airr, we find the residual path ∆ = (r–h), andthen, using literature data [14], we determinethe energy corresponding to the residual path ∆.

0,0 0,5 1,0 1,5 2,0 2,5 3,0 3,5 4,0 4,5 5,00

1x103

2x103

3x103

4x103

5x103

6x103

o-POPOP

Single-layer o-POPOP composite detector, L = 1,3-1,5 mm

Num

ber o

f pho

tons

P

Alpha Energy Ea, MeV

Fig.4. small Scintillation signal as function of ex-citation energy (alpha-excitation, scintillators basedon o-POPOP)

Amplitude scintillation spectra of scintillatorsbased on o-POPOP, stilbene and 1,4-diphenyl-1,3-butadiene obtained under irradiation by alpha-particles of different energies were rather similar andshowed no peculiar features.

Figs.4 and 5 show scintillation signals fromcomposite scintillators based on o-POPOP and1,4-diphenyl-1,3-butadien as function of excita-tion energy for the case of alpha particles.

0,0 0,5 1,0 1,5 2,0 2,5 3,0 3,5 4,0 4,5 5,00

1x103

2x103

3x103

4x103

5x103

6x103

1,4-diphenyl-2,3-butadiene

Single-layer composite detector (thin DFB crystalline plates)

Num

ber o

f pho

tons

P

Alpha Energy Ea, MeV

Fig.5. Scintillation signal as function of excita-

tion energy (alpha-excitation, scintillators based on 1,4-

diphenyl-1,3-buradiene)

3. SAMPLE PREPARATIONTECHNOLOGY FEATURES

3.1. Light transmission in the systemsstudied

Composite scintillators are distinguished, as com-pared to conventional systems, by their universalityand much broader application possibilities. Proper-ties of known scintillators are generally characterizedby two main groups of parameters: 1–volume (ac-counting for shape); 2–chemical composition. In thecase of composite scintillators, the third group of pa-rameters becomes important, related to the size ofscintillation granules. Therefore for short-range radi-ations, accounting for transparence features of thesesystems, thin-layered samples shouls be developed.For penetrating radiations, such as fast neutrons, op-timal number of layers should be determined. Thisnumber should be sufficiently high to ensure efficientinteraction and sufficiently low to ensure light out-put from the scintillator. Thus, for detection of fastneutrons the optimum thickness was determined as20 mm (see Chapter 2.1), while for thermal neu-trons – single-layered systems with granule size of30-100 microns. In this respect, it is important tostudy the transparence characteristics of compositescintillators as function of thickness.

Since light propagation in such systems is ofdiffuse character, it is reasonable to study trans-parence as function of average granule size at dif-ferent wavelengths. This is very important for de-velopment of layered systems, where radiation detec-tion efficiency is directly dependent on light transmis-

93

sion through the scintillator. Measurements of opti-cal transmission for single-layered and multi-layeredstilbene-based samples were carried out using a Shi-madzu 2450 spectrophotometer with an integratingsphere. The spectral measurement range was from300 to 700 nm. The results obtained show thatfor composite scintillators based on crystalline gran-ules of stilbene there is strong light absorption at360 nm, while the material was practically trans-parent at 700 nm. The intensity of light transmit-ted through the composite scintillator is decreasedwith higher thickness, which is related to an increasein the number of layers of light-scattering granules.

0,5 1,0 1,5 2,0 2,5 3,0 3,5 4,0 4,5 5,01x103

2x103

3x103

4x103

5x103

6x103

7x103 single crystal 30 mm 3mm

Num

ber o

f pho

tons

P

Average grain size Lav

, mm

alpha particles 239Pu

Fig.6. Number of light photons as function of theaverage size of crystalline stilbene granules for multi-layered composite scintillators ⊘ 30 mm × 20 mm(circles) and single-layered composite scintillators⊘ 30 mm (squares)

The transparence dependence on the averagegranule size is of the same character as the similardependence of the number of photons. For single-layer systems practically no effect of the grain sizeis observed, while for multi-layered systems smallergranule size, which means larger contribution fromthe scattering boundaries, both scintillation signaland transmission are decreased, which should beaccounted for in development of multi-layered scin-tillators [8, 15, 16].

3.2. Detectors with unlimited size of theinput window

The main advantage of composite scintillators, ascompared with structurally perfect organic singlecrystals, is the possibility to create radiation detec-tors with no limitations on the input window sizeand shape. For scintillators of large area, a problememerges due to possible non-uniformity of the lightsignal obtained in irradiation of different points ofthe scintillator surface. For our studies, we chose,as an example, composition detectors of diameter200 mm. This size was considered as sufficient forcheck-up of uniformity of scintillation characteristics[17]. The scatter of relative light output values mea-sured in different regions of composite scintillator of200 mm diameter did not exceed 1%, i.e., less thanthe standard 5% error of light output measurements.

Thus, it can be concluded that our proposed chain oftechnological procedures allows preparation of uni-form composite detectors with large output windows.Technological preparation procedures of compositescintillators impose no limitations on the area andshape of the input window; however, such limita-tions can be due to other factors, e.g., conditionsof transportation and assembling of the detector.

CCoonnnneeccttiioonn lliinnee

Fig.7. Connection of separate parts of the compositescintillator

Fig.7 shows an approach to this problem. First, sam-ples of smaller size are fabricated, which are thenglued together by a non-scintillating dielectric gel.The connection line is indicated by arrow [16].

3.3. Technological features of preparation ofcomposite scintillators for different

applications.

Our technology allows introduction of granules of anynature into a binding base. Thus, application pos-sibilities of composite scintillators for different tasksare probably the highest as compared with other scin-tillation systems.

The technological chain for preparation of com-posite scintillation materials on the basis of crys-talline granules of stilbene and p-terphenyl (Fig.8,path I) was the first step in creation of new scin-tillation materials [1, 18, 19]. We have noticed thatproperties of the obtained composite scintillators areweakly dependent upon structural perfectness of theinitial organic crystals. We made an attempt to makethe fabrication process of organic scintillators cheaperand simpler, taking stilbene single crystals as exam-ple (see Fig.8, path II).

The most energy-consuming and expensive stageof preparation of composite scintillators is the pro-cess of growth of structurally perfect single crystals.For single crystal growth, preliminary purification ofthe raw material is carried out by method of direc-tional crystallization. The primary crystal obtainedhas rather large number of defects, and such samplecannot be directly used as a bulky single crystallinescintillator. In preparation of crystalline granules bycryogenic fragmentation, the primary crystal is frag-mented over the defects into many micro-single crys-tals.

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Calculated values of the local field strength Eloc created by the pair of polaron states M−p and M+

p inanthracene crystal

Technological Sample based on granules Sample based on granulesoperations of grown single crystal of primary crystal

Raw material purification by 168 168directional crystallization, hoursPreparation of ampoule with 7 –raw material for growth, hoursSingle crystal growth*, hours 240 –

Fragmentation at low temperature, hours 1.5 1.5Preparation of scintillator (selectionof fractions, introduction into binder 61 61and binder polymerization), hours

Total, hours 477,5 230,5

* For single crystal sample of 20 mm diameter and 10 mm height. With larger volume of required raw material,the difference between the required rime by two methods increases.

The obtained granules were separated into fractionsof different sizes, and composite scintillators were fabri-cated using technological procedures worked out in ourstudies. I.e., with our approach, we can obtain compositescintillators omitting the stage of growing single crystalsof high structural perfectness. Duration of technologicaloperations in preparation of organic scintillators is shownin Table.

Our studies have shown that composite scintil-lators prepared from crystalline granules of stilbeneobtained from the primary crystal (after raw mate-rial purification by directional crystallization) have asgood scintillation characteristics as composite scintil-lators prepared from granules obtained from a pre-grown single crystal of high structural perfection [18].

Fig.8. Flow chart of technological chain for prepa-ration of composite scintillators: I, II – on the basisof crystalline granules of stilbene and p-terphenyl us-ing traditional and modified (i.e., without stage of grow-ing structurally perfect single crystal) technology, respec-tively; III – on the basis of crystalline granules of gadolin-ium silicate (Ce:GSO) or pyrosilicate (Ce:GPS) activatedby Ce

Path III in Fig.8 demonstrates technological opera-tions of preparation of composite scintillators on the ba-sis of crystalline granules of gadolinium silicate (Ce:GSO)or pyrosilicate (Ce:GPS) activated by Ce [19]. Such scin-tillators are efficient detectors of thermal neutrons (seeChapter 2.2).

3.4. Possibility to use composite scintillatorsunder high radiation loads. Prospects ofincreasing radiation stability of composite

scintillators.

With a new generation of accelerators, such as, e.g.,LHC CERN (Switzerland), irradiation intensity of detec-tors used in such installations has substantially increased.Thus, for the end-cap hadronic calorimeter (Hadron End-cap (He)) of CMS detector CMS (LHC CERN) they usescintillation detecting plates (tiles), with some of themlocated near the beam axis, where particle flux intensityis high, and correspondingly high are the dose loads. Af-ter 10 years of operation of CMS-detector, the total dosereaches 10 Mrad at average dose rate 1 Mrad/year or0.0001 Mrad/hour.

Therefore, there is a constantly growing interest in in-creasing the radiation stability of scintillators. We havemade a first step in this direction. We obtained infor-mation on radiation stability of materials that can beused as a base for composite scintillators. These mate-rials are industrially produced gels required for creationof radiation-resistant detectors on their base [20]. Thisjustifies our search in this direction.

4. CONCLUSIONS

Analysis of the results obtained for scintillation charac-teristics of composite scintillators allows us to make thefollowing conclusions:

1. We have developed composite scintillators com-posed of crystalline granules introduced into an organo-silicon base. The obtained scintillation materials are nothygroscopic, non-combustible, have no technological limi-tations on the size and shape of the input window. Thesematerials show selectivity to detected signals, good scin-tillation characteristics, as well as high spatial uniformityof the scintillation signal.

2. A procedure has been developed for connectionof separate parts of composite scintillators, which allowsfabrication of scintillators with really unlimited area ofthe input window. This is achieved by connecting sepa-rate parts in assembling the scintillator at location of itsapplication.

3. It has been shown that the developed technologycan be used not only for traditional organic scintillation

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materials, but also for materials which cannot be grownfrom the melt as bulky crystals.

4. The obtained information on radiation stability ofgel dielectric bases allows us to state that the use of suchmaterials for preparation of composite scintillators is oneof the promising directions in improvement of character-istics of detecting devices.

ACKNOWLEDGEMENTS

This work was supported by the State Fund for Funda-mental Research of Ukraine (project No. F58/06, ”Theeffect of large radiation doses on scintillation and opticalproperties of novel types of organic detectors”).

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ÊÎÌÏÎÇÈÖÈÎÍÍÛÅ ÑÖÈÍÒÈËËßÒÎÐÛ ÊÀÊ ÍÎÂÛÉ ÂÈÄ ÑÖÈÍÒÈËËßÖÈÎÍÍÎÃÎÌÀÒÅÐÈÀËÀ

Í.Ë.Êàðàâàåâà

Äëÿ ðàäèîýêîëîãè÷åñêèõ çàäà÷ íàìè áûë ðàçðàáîòàí íîâûé âèä ñöèíòèëëÿöèîííîãî ìàòåðèàëà � êîìïîçèöè-îííûå ñöèíòèëëÿòîðû, ñîñòîÿùèå èç äèýëåêòðè÷åñêîãî ãåëÿ â êà÷åñòâå îñíîâû, â êîòîðóþ âíåäðåíû ãðàíóëûñöèíòèëëèðóþùåãî âåùåñòâà. Ïîêàçàíî, ÷òî äàííûé ìàòåðèàë ìîæåò ñîçäàâàòüñÿ êàê íà îñíîâå îðãàíè÷åñêèõ,òàê è íåîðãàíè÷åñêèõ ãðàíóë. Ïåðâûå ïîçâîëÿþò ñîçäàâàòü ýôôåêòèâíûå äåòåêòîðû áûñòðûõ íåéòðîíîâ ñîñòåïåíüþ ðàçäåëåíèÿ íåéòðîíîâ íà ôîíå ãàììà-èçëó÷åíèÿ, áëèçêîé ê îðãàíè÷åñêèì ìîíîêðèñòàëëàì. Âòîðûåÿâèëèñü ýôôåêòèâíûìè äåòåêòîðàìè òåïëîâûõ íåéòðîíîâ, à âàðüèðîâàíèå ðàçìåðîâ èõ ãðàíóë ïîçâîëèëî ñó-ùåñòâåííî óìåíüøèòü âëèÿíèå ôîíîâûõ èçëó÷åíèé. Îòäåëüíûå ôðàãìåíòû ñöèíòèëëÿòîðà ìîæíî ñîåäèíÿòüâìåñòå, ñîçäàâàÿ áåñêîíå÷íûå ïëîñêîñòè. Âîçìîæíîñòü âûáîðà áîëåå ðàäèàöèîííî-ñòîéêèõ îñíîâ, ÷åì ñòàí-äàðòíûå ñöèíòèëëÿöèîííûå îñíîâû, è ëþáûõ ñöèíòèëëÿöèîííûõ âåùåñòâ äëÿ ñîçäàíèÿ ãðàíóë ïîçâîëÿåò çà-äóìàòüñÿ î âîçìîæíîñòè èñïîëüçîâàíèÿ òàêîãî òåõíîëîãè÷åñêîãî ïîäõîäà íå òîëüêî äëÿ çàäà÷ ðàäèîýêîëîãèè(ñâåðõìàëûå ïîòîêè), íî è äëÿ çàäà÷ ôèçèêè âûñîêèõ ýíåðãèé.

ÊÎÌÏÎÇÈÖIÉÍI ÑÖÈÍÒÈËßÒÎÐÈ ßÊ ÍÎÂÈÉ ÂÈÄ ÑÖÈÍÒÈËßÖIÉÍÎÃÎÌÀÒÅÐIÀËÓ

Í.Ë.Êàðàâà¹âà

Äëÿ ðàäiîåêîëîãi÷íèõ çàäà÷ íàìè áóâ ðîçðîáëåíèé íîâèé âèä ñöèíòèëÿöiéíîãî ìàòåðiàëó � êîìïîçèöiéíi ñöèí-òèëÿòîðè, ùî ñêëàäàþòüñÿ ç äiåëåêòðè÷íîãî ãåëþ â ÿêîñòi îñíîâè, â ÿêó ââåäåíi ãðàíóëè ñöèíòèëþþ÷î¨ ðå÷î-âèíè. Ïîêàçàíî, ùî äàíèé ìàòåðiàë ìîæå ñòâîðþâàòèñÿ ÿê íà îñíîâi îðãàíi÷íèõ, òàê i íåîðãàíi÷íèõ ãðàíóë.Ïåðøi äîçâîëÿþòü ñòâîðþâàòè åôåêòèâíi äåòåêòîðè øâèäêèõ íåéòðîíiâ ç ñòóïåíåì ïîäiëó íåéòðîíiâ íà ôîíiãàììà- âèïðîìiíþâàííÿ, áëèçüêîþ äî îðãàíi÷íèõ ìîíîêðèñòàëiâ. Äðóãi ¹ åôåêòèâíèìè äåòåêòîðàìè òåïëîâèõíåéòðîíiâ, à âàðiþâàííÿ ðîçìiðiâ ¨õ ãðàíóë äîçâîëèëî iñòîòíî çìåíøèòè âïëèâ ôîíîâèõ âèïðîìiíþâàíü. Îêðå-ìi ÷àñòèíè ñöèíòèëÿòîðà ìîæíà ç'¹äíóâàòè ðàçîì, ñòâîðþþ÷è íåñêií÷åííi ïëîùi. Ìîæëèâiñòü âèáîðó áiëüøðàäiàöiéíîñòiéêèõ îñíîâ, íiæ ñòàíäàðòíi ñöèíòèëÿöiéíi îñíîâè, òà áóäü-ÿêèõ ñöèíòèëÿöiéíèõ ðå÷îâèí äëÿ ñòâî-ðåííÿ ãðàíóë äîçâîëÿ¹ çàìèñëèòèñÿ ïðî ìîæëèâiñòü âèêîðèñòàííÿ òàêîãî òåõíîëîãi÷íîãî ïiäõîäó íå òiëüêè äëÿçàäà÷ ðàäiîåêîëîãi¨ (íàäñëàáêi ïîòîêè), à é äëÿ çàäà÷ ôiçèêè âèñîêèõ åíåðãié.

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