Training Example: Scionix – Review the Data, Give Your Score & Compare to the Real AI Evaluation

This site uses cookies. By continuing to browse the site, you are agreeing to our use of cookies.AgreeLearn more
[H3] Cookie and Privacy Settings
How we use cookiesWe may request cookies to be set on your device. We use cookies to let us know when you visit our websites, how you interact with us, to enrich your user experience, and to customize your relationship with our website.
Click on the different category headings to find out more. You can also change some of your preferences. Note that blocking some types of cookies may impact your experience on our websites and the services we are able to offer.
One button to accept all cookies and services with a single click.
Accept use of all cookies and services
Check to enable permanent hiding of message bar and refuse all cookies if you do not opt in. We need 2 cookies to store this setting. Otherwise you will be prompted again when opening a new browser window or new a tab.
Click to enable/disable essential site cookies.
allows a user to opt out from essential theme and all other cookies (except 2 from av_privacy_allow_cookies)
Essential Website CookiesThese cookies are strictly necessary to provide you with services available through our website and to use some of its features.
Because these cookies are strictly necessary to deliver the website, you cannot refuse them without impacting how our site functions. You can block or delete them by changing your browser settings and force blocking all cookies on this website.
One button to accept all cookies and services with a single click.
Accept use of all cookies and services
Refuse cookies and hides message bar.
Check to enable permanent hiding of message bar and refuse all cookies if you do not opt in. We need 2 cookies to store this setting. Otherwise you will be prompted again when opening a new browser window or new a tab.
Opt out from all the cookies (except 2 from av_privacy_allow_cookies)
Click to enable/disable essential site cookies.
Disable Google tracking
Click to enable/disable Google Analytics tracking.
Disable Google webfonts
Click to enable/disable Google Webfonts.
Disable Google reCaptcha
Click to enable/disable Google reCaptcha.
Disable Google Maps
Click to enable/disable Google Maps.
Disable video embeds
Click to enable/disable video embeds.
Adds an accept cookies button
Accept all cookies
Adds a do not accept cookies button
Klik hier om geen cookies te accepteren
Google Analytics CookiesThese cookies collect information that is used either in aggregate form to help us understand how our website is being used or how effective our marketing campaigns are, or to help us customize our website and application for you in order to enhance your experience.
If you do not want that we track your visist to our site you can disable tracking in your browser here: Click to enable/disable Google Analytics tracking.
Other external servicesWe also use different external services like Google Webfonts, Google Maps and external Video providers. Since these providers may collect personal data like your IP address we allow you to block them here. Please be aware that this might heavily reduce the functionality and appearance of our site. Changes will take effect once you reload the page.
Google Webfont Settings:
Click to enable/disable Google Webfonts.
Google Map Settings:
Click to enable/disable Google Maps.
Vimeo and Youtube video embeds:
Click to enable/disable video embeds.
Privacy Policy + Terms and conditionsYou can read about our cookies and privacy settings in detail on our Privacy Policy Page.
Terms and conditions
Accept settingsHide notification only

Menu
Properties
Afterglow
Neutron Detection
Radiation Damage
Emission Spectra
Temperature Influence
Your Application?
[H1] Scintillation Crystals
150.000+UNITS SOLD
Properties and use of scintillation materials
A large number of different scintillation crystals exist for a variety of applications. Some important characteristics of scintillators are:
Density and atomic number (Z)
Light output (wavelength + intensity)
Decay time (duration of the scintillation light pulse)
Mechanical and optical properties
Cost
Density and atomic number (Z)Density and atomic number (Z)
It is clear that for an efficient detection of γrays, a material with a high density and high effective Z (number of protons per atom) is required (see above). Inorganic scintillation crystals meet the requirements of stopping power and optical transparency, their densities ranging from roughly 3 to 9 g/cm3 makes them very suitable to absorb penetrating radiation (γ-rays). Materials with high Z-values are used for γ-ray spectroscopy at high energies (> 1 MeV).
Light output (wavelength + intensity)Light output (wavelength + intensity)
Since photoelectron statistics (or electron-hole pair statistics) plays a key role in the accurate determination of the energy of the radiation, the use of scintillation materials with a high light output is preferred for all spectroscopic applications. The scintillator emission wavelength should be matched to the sensitivity of the light detection device that is used (PM, SiPm or photodiode).
Decay time (duration of the scintillation light pulse)Decay time (duration of the scintillation light pulse)
Scintillation light pulses (flashes) are usually characterized by a fast increase of the intensity in time (pulse rise time) followed by an exponential decrease. The decay time of a scintillator is defined by the time after which the intensity of the light pulse has returned to 1/e of its maximum value. Most scintillators are characterized by more than one decay time and usually, the effective average decay time is mentioned. The decay time is of importance for fast counting and / or timing applications.
Mechanical, optical and scintillation properties
[H5] Mechanical, optical and scintillation properties
The most widely used scintillation material for gamma-ray spectroscopy NaI(Tl) is hygroscopic and is only used in hermetically sealed metal containers to preserve its properties. All water soluble scintillation materials should be packaged in such a way that they are not attacked by moisture. Some scintillation crystals may easily crack or cleave under mechanical pressure whereas others are plastic and only will deform like CsI(Tl).
In table 3.1 below, the most important aspects of commonly used scintillation materials are listed. The list is not extensive and new materials are developed regularly.
Physical properties of the most common scintillation materials
Material
Density
(g/cm3)
Emission
Maximum
(nm)
Decay
Constant
(1)

Refractive
Index
(2)
Conversion
Efficiency
(3)
Hygroscopic
NaI(Tl)
3.67
415
0,23 µs
1.85
100
yes
CsI(Tl)
4.51
550
0,6/3.4 µs
1.79
45
slightly
CsI(Na)
4.51
420
0.63 µs
1.84
85
yes
CsI(Undoped)
4.51
315
16 ns
1.95
4-6
no
Cs2LiYCl6:Ce
(CLYC)
3.31
275-450 nm
1,50,1000 ns
1.81
30-40
yes
CaF2(Eu)
3.18
435
0.84 µs
1.47
50
no
LaCl3:Ce(0.9)
3.79
350
70 ns
1.90
95-100
yes
SrI2(Eu)
4.60
450
1-5 µs
1.85
120-140
yes
LaBr2.85Cl0.15:Ce (LBC)
4.90
380
35 ns
1.90
140
yes
6Li-glass
2.6
390/430
60 ns
1.56
4-6
no
Cs2LiLaBr4.8
Cl1.2 Ce (CLLBC)
4.08
420
120 ns
500 ns
1.90
84
yes
6Li(Eu)
4.08
470
1.4 µs
1.96
35
yes
BaF2
4.88
315
220
0.63 µs/
0.8 ns
150
1.54
16
5
no
CeBr3
5.23
370
18 ns
1.9
130
yes
YAP(Ce)
5.55
350
27 ns
1.94
35-40
no
LYSO:Ce
7.20
420
50 ns
1.82
70-80
no
BGO
7.13
480
0.3 µs
2.15
15-20
no
CdWO4
7.90
470/540
20/5 µs
2.3
25-30
no
PbWO4
8.28
420
7 ns
2.16
0.20
no
Plastics(*)
1.023
375-600
ns range
1.58
25-30
no
(1) Effective average decay time for γ-rays.
(2) At the wavelength of the emission maximum
(3) Relative scintillation signal at room temperature for γ-rays when coupled to a photomultiplier
tube with a bi-alkali photocathode.
(*) approximate data
Each scintillation crystal has its own specific application. For high resolution γray spectroscopy, NaI(Tl), or CeBr3 (high light output) are often used. For high energy physics applications, the use of bismuth germanate Bi4Ge3O12 (BGO) crystals (high density and Z) or Lead Tungstate (PbWO4) improves the lateral confinement of the shower. For the detection of β-particles, CaF2(Eu) or YAP:Ce can be used instead of plastic scintillators (higher density).
Scintillation materials and their most common applications
​
Material
Important properties
Major Application
NaI(Tl)
Very high light output, good energy resolution
General scintillation counting, Health Physics, environmental monitoring, high temperature use
CsI(Tl)
Non-hygroscopic, rugged
Particle and high energy physics, general radiation detection, photo diode readout,
CsI(Na)
High light output, rugged
Geophysical, general radiation detection
CsI(Undoped)
Fast, non-hygroscopic
Physics (calorimetry)
CaF2(Eu)
Low Z, high light outputβ detectors, α/β phoswiches
β detectors, α/β phoswiches
Cs2LiYCl6:Ce
(CLYC)
Neutron detection capability High resolution
Nuclear identifiers, Physics
LaCl3:Ce(0.9)
Very high light output, very good energy resolution
High resolution scintillation spectroscopy, Health Physics environmental monitoring
CeBr3
Very high light output, very good energy resolution, low background
High resolution spectroscopy, low background applications
6Lil(Eu)
High neutron cross-section, high light output
Thermal neutron detection and spectroscopy
LaBr2.85Cl0.15:
Ce (LBC)
Bright, high resolution scintillator (La-138 background)
High resolution gamma spectroscopy
Cs2LiLaBr4.8
Cl1.2 Ce
(CLLBC)
High resolution scintillator with neutron capabilities
Physics, security
SrI2(Eu)
Bright, high resolution scintillator
High resolution gamma Spectroscopy
6Li-glass
High neutron cross section, non hygroscopic
Physics, security
BaF2
Ultra-fast sub-ns UV emission
Thermal neutral detection
YAP(Ce)
High light output, low Z, fast
Positron life time studies,physics, fast timing
LYSO
High density and Z, fast
Mhz-X-ray spectroscopy, synchrotron physics
BGO
High density and Z
Physics resarch, PETT, High Energy Physics
CdWO4
Very high density, low afterglow. Slow decay times
Particle physics, geophysical research PET, anti- Compton spectrometers.
PbWO4
Fast, high density, low afterglow
DC measurement of   x-rays (high intensity), readout with photodiodes, Computerized Tomography (CT)
Plastics
Fast, low density and Z high light output
Physics research (calorimetry). General counting, particle and neutron detection.
NaI(Tl) scintillation crystals are used in a great number of standard applications for detection of γ-radiation because of their high light output and the excellent match of the emission spectrum to the sensitivity of photomultiplier tubes, resulting in a good energy resolution. In addition NaI(Tl) is a relatively inexpensive scintillator. NaI(Tl) crystals show a distinct non proportionality (see below) which results in a limitation of the energy resolution at 662 keV to about 6% FWHM, NaI(Tl) crystals can be grown to large dimensions (400 mm diameter) in ingots of many hundreds of kg. The material can be cut in a great variety of sizes and shapes and cleaved in small diameters.
CsI(Tl) has the advantage that it not really hygroscopic (its surface however is influenced by humidity on the long term),and does not cleave or crack under stress. It is a relatively bright scintillator but its emission is located above 500 nm where PMTs are not that sensitive. However due to this property it can effectively be read out by silicon photodiodes or SiPms. Thanks to its different decay times for charged particles having a different ionizing power, CsI(Tl) crystals are frequently used in arrays or matrices in particle physics research.
CsI(Na) is a hygroscopic high light output rugged scintillator Like CsI(Tl) mainly used for applications where mechanical stability and good energy resolution are required. Below 120 oC it is an alternative to NaI(Tl). CsI(Na) has its emission peaking at 400 nm like NaI(Tl).
Undoped (pure) CsI is an intrinsic scintillator with same density and Z as CsI(Na). It has en emission at approx. 300 nm and since it intensity is strongly thermally quenched at room temperature it is relatively fast (ns decay time). There is a slow component present in this crystal that makes up at least 10% of the total light yield. The emission spectra below show how the emission spectrum of a scintillator can be influenced by its type of activation.
CaF2(Eu) , Europium doped calcium fluoride is a rather old low density scintillation crystal . Thanks to its low Z value it is well suited for the detection of electrons (beta particles) with a high efficiency (low backscatter fraction). CaF2(Eu) is a relatively slow scintillator that is not hygroscopic and inert to many chemicals. It is brittle and cleaves relatively easy.
(6) LiI(Eu) is used for the detection of thermal neutrons via the reaction
The total Q-value of the alpha and the triton is 4.78 MeV. The resulting thermal neutron peak can be found at a Gamma Equivalent Energy larger than 3 MeV. This allows to separate neutron interactions from gamma events (< 2.6 MeV). Since the typical absorption length (90%) of thermal neutrons in 6-LiI(Eu) crystals is only 3 mm the efficiency for gamma rays can be made small. LiI(Eu) crystals are grown up to 25 mm in diameter.
6-Li glass scintillators offer the same possibility as 6LiI(Eu) crystals to detect thermal neutrons. However, The light output is much lower than of LiI(Eu) scintillators and therefore the neutron peaks are relative broad. In addition the scintillation efficiency for the resulting particles is low so that the neutron peak appears at a location of approximately 1.6 MeV in the gamma energy spectrum. 90% of thermal neutrons are absorbed in only1 mm of material.
All 6-Li containing scintillators can also be used for the detection of fast neutrons but the efficiency of the nuclear reaction is smaller.
Further details on neutron detection can be found in the application note “neutron detection with scintillators”.
Barium Fluoride (BaF2) is a non-hygroscopic scintillator with a very fast decay component located at 220 nm. To detect this component, light detectors with quartz windows are used.
Barium fluoride detectors allow fast sub-nanosecond timing for example for positron life time measurements. It is a weak scintillator with a modest energy resolution at 662 keV (typically about 10-12 % FWHM @ 662 keV.
BGO (Bi4Ge3O12) has the extreme high density of 7.13 g/cm3 and has a high Z value which makes these crystals very suited for the detection of natural radioactivity (U, Th, K), for high energy physics applications (high photo fraction) or in compact Compton suppression spectrometers. Since the light output of BGO is modest, the energy resolution is inferior to that of the the standard alkali halides like NaI(Tl) or CsI(Tl).
YAP:Ce (YAlO3:Ce) is a high density (5.5 g/cm3) oxide crystal with a decay time about 10 times shorter than NaI(Tl) (23 ns) It is used in detectors for high count rate (up to several MHz) The non-hygroscopic nature of this material allows the use of thin mylar entrance windows. YAP:Ce can withstand gamma doses up to 104 Gray.
High resolution (proportional) scintillatorsHigh resolution (proportional) scintillators
Currently there is an increased better understanding of the properties of scintillators and what determines their intrinsic energy resolution. A number of materials have been developed that exhibits a more proportional response to gamma rays than the classic alkali halides (NaI(Tl), CsI(Tl) etc). This has resulted in the availability of a class of proportional scintillators. New materials are being developed constantly and the list below is not extensive.
Bright proportional scintillator scan have energy resolutions around 3-4 % at 662 keV gamma rays under optimum light detection conditions. Just as other scintillators each have some advantages and disadvantages. Some typical proportionality curves are shown below:
Ref. W. Mengesha, T.D. Taulbee, B .D. Rooney, and J.D. Valentine.Light Yield
Nonproportionality of CsI(Tl), CsI(Na), and YAP IEEE Trans. Nucl. Sci. vol 45, no. 3,
(1998) pp. 456–461
Proportional scintillators only offer their superior performance in energy resolution when the light detection is optimized by covering the largest possible area with light detector (PMT or SiPm).
LBC (Lanthanum BromoChloride) LaBr2.85Cl0.15:Ce scintillators have similar properties to the well-known LaBr3:Ce crystals. Energy resolutions around 3.0% FWHM (662 keV) are standard and the material is mechanically a little stronger than LaBr3. LBC crystals suffer from the same La-138 background as LaBr3
CeBr3 (Cerium Bromide) scintillators are characterized by a relatively high density and Z and a proportional response to gamma rays. Typical energy resolutions are 4% FWHM for 662 keV.
The material exhibits a fast decay of typical 20 ns (for 51 mm crystals) with a negligible afterglow. CeBr3 is highly hygroscopic and provides the best performance when integrally coupled to PMTs. Thanks to its fast light pulse rise time, CeBr3 detectors can provide sub nanosecond time resolutions, slightly worse than BaF2 detectors. With CeBr3 scintillators the 609 and 662 keV gamma lines from respectively radium and Cs-137 can easily be separated.
Cs2LiYCl6:Ce (CLYC) scintillation crystals offer a reasonable density of 3.3 g/cc. This proportional crystal offers an energy resolution of 4.5 – 5 % FWHM for 662 keV gamma rays. The thermal neutron peak due to the n-6Li reaction produces a narrow peak at approximately 3.3 MeV. Its fast scintillation component is not excited by neutrons which opens PSD capabilities or further improve the neutron/gamma separation. CLYC has some slower emission components so larger signal shaping times are required. To absorb 90% of thermal neutron 12.5 mm of crystal is needed.
Cesium Lanthanum Lithium BromoChloride) CLLBC , Cs2LiLaBr4.8Cl1.2:Ce scintillators have properties to the well-known LaBr3:Ce crystals. Energy resolutions around 3 % FWHM (662 keV) are standard. In addition, thanks to the presence of Lithium, the material can be used for neutron detection with a sharp thermal neutron peak between 3.1- 3.2 MeV. In addition, CLLBC offers excellent neutron / gamma discrimination using PSD.
SrI2(Eu), Europium doped strontium iodide Is a very bright relatively slow scintillator with a very good proportionality. Typical energy resolutions are 3.5% @ 662 keV and 6% @ 122 keV. The material is quite radiopure. Due to its intrinsic self-absorption (small stokes shift), the crystal requires some special surface preparation techniques. The long decay time requires very long (digital) shaping time

This site uses cookies. By continuing to browse the site, you are agreeing to our use of cookies.AgreeLearn more
[H3] Cookie and Privacy Settings
How we use cookiesWe may request cookies to be set on your device. We use cookies to let us know when you visit our websites, how you interact with us, to enrich your user experience, and to customize your relationship with our website.
Click on the different category headings to find out more. You can also change some of your preferences. Note that blocking some types of cookies may impact your experience on our websites and the services we are able to offer.
One button to accept all cookies and services with a single click.
Accept use of all cookies and services
Check to enable permanent hiding of message bar and refuse all cookies if you do not opt in. We need 2 cookies to store this setting. Otherwise you will be prompted again when opening a new browser window or new a tab.
Click to enable/disable essential site cookies.
allows a user to opt out from essential theme and all other cookies (except 2 from av_privacy_allow_cookies)
Essential Website CookiesThese cookies are strictly necessary to provide you with services available through our website and to use some of its features.
Because these cookies are strictly necessary to deliver the website, you cannot refuse them without impacting how our site functions. You can block or delete them by changing your browser settings and force blocking all cookies on this website.
One button to accept all cookies and services with a single click.
Accept use of all cookies and services
Refuse cookies and hides message bar.
Check to enable permanent hiding of message bar and refuse all cookies if you do not opt in. We need 2 cookies to store this setting. Otherwise you will be prompted again when opening a new browser window or new a tab.
Opt out from all the cookies (except 2 from av_privacy_allow_cookies)
Click to enable/disable essential site cookies.
Disable Google tracking
Click to enable/disable Google Analytics tracking.
Disable Google webfonts
Click to enable/disable Google Webfonts.
Disable Google reCaptcha
Click to enable/disable Google reCaptcha.
Disable Google Maps
Click to enable/disable Google Maps.
Disable video embeds
Click to enable/disable video embeds.
Adds an accept cookies button
Accept all cookies
Adds a do not accept cookies button
Klik hier om geen cookies te accepteren
Google Analytics CookiesThese cookies collect information that is used either in aggregate form to help us understand how our website is being used or how effective our marketing campaigns are, or to help us customize our website and application for you in order to enhance your experience.
If you do not want that we track your visist to our site you can disable tracking in your browser here: Click to enable/disable Google Analytics tracking.
Other external servicesWe also use different external services like Google Webfonts, Google Maps and external Video providers. Since these providers may collect personal data like your IP address we allow you to block them here. Please be aware that this might heavily reduce the functionality and appearance of our site. Changes will take effect once you reload the page.
Google Webfont Settings:
Click to enable/disable Google Webfonts.
Google Map Settings:
Click to enable/disable Google Maps.
Vimeo and Youtube video embeds:
Click to enable/disable video embeds.
Privacy Policy + Terms and conditionsYou can read about our cookies and privacy settings in detail on our Privacy Policy Page.
Terms and conditions
Accept settingsHide notification only

In this section, a short overview of the use and general principle of scintillation detectors is presented. Scintillation crystal parameters in relation to the application are discussed.
A scintillator is a material that converts energy lost by ionizing radiation into pulses of light. In most scintillation counting applications, the ionizing radiation is in the form of Xrays, γrays and α or βparticles ranging in energy from a few thousand electronvolts to several million electron volts (keVs to MeVs).