This document provides an introduction to radiation technologies, including: - Radiation technologies use electron beams, X-rays, and gamma photons to irradiate materials, finding applications in industry, medicine, and more. - Adiabatic radiation technologies allow rapid irradiation using pulsed beams, maintaining material properties and enabling new material synthesis. - Electron accelerators and X-ray sources are key equipment for radiation technologies, with pulsed systems enabling adiabatic processing and improved dose control.

1. INTRODUCTION TO RADIATION
TECHNOLOGIES
Dr. Sergey Korenev
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2. Radiation technologies based on the irradiation of condensed matter
( product) by electron beam, X-rays and photons (gamma).
The low level of kinetic energy of particles ( 0.1-10 MeV) allows to
make radiation safety technologies.
Radiation technologies found large applications in the industry and
our life: curing of polymers, treatment of cables, semiconductors,
sterilization of medical products, X-imaging, CT and etc.
2

3. Market
STERILIZATION
X-RAY IMAGING AND CT
MATERIALS
MICROWAVE GENERATION
PLASMA CHEMISTRY
SCIENCE
5%
5%
30%
15%
15%
30%
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4. General concept of beam
technologies
ELECTRO-KINETIC TRANSFORMER
OF ENERGY
Energy storage
Capacitor
E = CU2/2
Potential
energy
Charge particle
transformer
E = N*mv2/2
Kinetic
energy
Object condensed
matter
Dissipation
of energy
Small size of particles, high speed,
penetration and depth of penetration
depends on kinetic energy
4

5. Electron beam technologies
Electron
Accelerator
Electrons
Product
Control of absorbed
doses
5

6. Absorbed dose
Absorbed dose
Dose max
Acceptable
absorbed dose
Dose min
Dose min
0
Dmax  Dmin
Dave 
2
Acceptable thickness
for irradiation
Thickness of product
6

7. Radiation technologies
 The time of delivered of energy of beam ( absorbed dose) is very
important for processes in the irradiated product.
 The decreasing of this time of leads to new type of radiation
technologies and processes – adiabatic radiation technologies.

The main benefits of adiabatic radiation technologies:
* saving of stoichiometric relationships for complex materials;
* short time of dissipation of beam energy;
* new physical properties and synthesis of new materials.
* surface modification of materials.
7

8. Beam current
Adiabatic radiation
technologies present
irradiation of condensed
mater by pulsed beams,
when beam current
pulse duration is low in
comparison with time
thermal constant.
Thickness of irradiated material
Adiabatic radiation technologies
Thermal constant of
irradiated material
Time
Time
8

9. Adiabatic irradiation
Penetration of
E-beam beam: X =F ( W)
 The distribution of temperature
Absorbed e-beam
dose
irradiated products is not high.
Sample
Temperature
gradient
in the irradiated sample as a
result of dissipation of energy
has a step character on the
depth of penetration of beam or
is close to it and as a result of it
average temperature of
Distance
9

10. Process with irradiated material
Beam
current
time
Temperature
1
2
3
time
10

11. Applications of adiabatic radiation
technologies
*
*
*
*
*
*
Semiconductors.
High Temperature Superconductors.
Plasma Chemistry.
Nanotechnologies.
Food Irradiation.
Sterilization.
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12. Semiconductors
 Surface modification of
semiconductors with saving of
stoichiometric relationships.
 Rapid annealing.
 Re-crystallization.
 Synthesis of semiconductor
structures.
12

13. High Temperature
Superconductors
 Surface modification of HTSC.
 Surface melting and re-
crystallization for Increasing of
critical current.
13

14. Plasma Chemistry
 Generation of free radicals for chain chemical
reactions.
 Generation of ozone.
 CVD deposition of films.
 Destruction of toxic components and gases from
electrical power stations (SOx, NOx), chemical
productions.
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15. Nanotechnologies
 Surface modification of materials.
 Synthesis of nanomaterials: nanorods
and etc.
 PTFE lubricants for quality printing,
engines and etc.
15

16. Food Irradiation
 Low dose (only 3 kGy)
for food irradiation.
 Irradiation of meet and
other products without
change of their
properties.
 Simple, safety and
acceptable equipment
for small companies.
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17. Sterilization
 Surface sterilization of packaging materials,
medical tools, lumens and etc.
 Fast sterilization in compared with VHP,
ozone, thermal sterilization.
 Simple and cheaper systems for sterilization.
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18. Equipment
 1. Electron accelerators.
 2. X-rays sources.
18

19. Structure of industrial irradiator
Conveyer
system
Product
Vacuum system
Electron
gun
Accelerating
structure
X-ray
target
Dose
control
Beam
scanning
system
Modulator
Control and operation system
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20. Electron accelerators
1. RF Linac: pulsed and CW.
2. DC Linac.
3. Linear Induction accelerator.
4. Rhodotron.
5. Betatron.
6. Microtron.
7. Diode pulsed high current accelerators.
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21. Example of companies for
electron accelerators
1. Ion Beam Applications ( IBA), Belgium
2. MEVEX, Ontario, Canada
3. Titan, USA
4. VARIAN, USA
5. Mitsubishi, Japan
6. Linac Technologies, France
7. Advanced Electron Beam (AEB), USA
8. Beam & Plasma Technologies, USA
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22. Main problem of e-beam
Optimal thickness of irradiated product
with low density
penetration to
irradiated product.
Thickness, cm
 Small depth of
 Alternative to e-beam
35
30
25
20
15
10
5
0
Density 0.1
g/cc
Density
1 g/cc
1
3
4
5
6
7
8
9
10
Kinetic energy of electrons, MeV
is X-rays:
Optimal thickness of irradiated product
Thickness, cm
X-ray system includes:
1. Electron accelerator
2. X-ray target
2
3.5
3
2.5
2
1.5
1
0.5
0
Density
1 g/cc
Density
2g/cc
Density
3 g/cc
1
2
3
4
5
6
7
8
9
10
Kinetic energy of electrons, MeV
22

23. X-rays sources
 Bremsstrahlung X-Rays
 Simple method for production of X-rays
using irradiation of target by electron
beams.
23

24. X-ray targets
Problems:
1. Low factor of conversion e-beam to Xrays
Kinetic energy by
electron, MeV
0.5
1.0
2.0
5.0
10.0
Coefficient of
conversion for Ta
target, %
1.2
2.3
3.5
8
13
Coefficient of
conversion for Al
target, %
0.1
0.3
0.5
2.5
5
2. High Thermal loads
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25. X-ray targets
1. Broad energy spectra
Ex~ 0.7*Ee
for
0.2 <Ee< 07 [MeV]
Ex ~ 0,6*Ee
for
0.7<Ee< 3 [MeV]
Ex ~ 0.5*E e
for
3<Ee<10 [MeV]
2. Different absorption factor of X-rays
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26. Pulsed electron accelerators
DIAGNOSTIC EQUIPMENT FOR BEAM AND FOR IRRADIATED MATERIALS
HIGH
VOLTAGE
SUPPLY
HIGH
VOLTAGE
GENERATOR
ELECTRON
SOURCE
CHAMBER FOR
IRRADIATION
VACUUM SYSTEM
26

27. Principle of pulsed diode
electron accelerator
Voltage
Time
Cathode
Cathode
plasma
Anode
Beam current
Time
Electrons
Moving cathode
plasma
Limit for beam pulse
duration
High Voltage Generator
Nanosecond electron beam
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28. High field emission cathodes
Explosive electron
emission
Current of vacuum arc
J4
J3
1. Carbon-fiber
cathodes.
2. Carbon
nanotube
cathodes.
3. Graphite
cathodes.
Current density
J2
Explosive
electron beam
current
Generation of
cathode plasma
Autoemission
current
J1
0
10 - 20 nsec
1- 10 nsec
1-200 nsec
1-10
nsec
Time
28

29. Carbon-Fiber Cathode
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30. Pulsed electron accelerators
from Beam & Plasma Technologies
Main parameters of pulsed electron accelerators:
1. Kinetic energy: 10 – 1000 keV.
2. Beam current: 1- 5000 A.
3. Pulse duration: 5 – 1000 nsec.
4. Mode of operation: electrons and X-rays.
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31. Dose monitoring and control
 The routine control of absorbed dose by
film dosimeters.
 Real-time (On-line) system for monitoring
and control of absorbed dose in
irradiated product.
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32. Radiation safety
The electron accelerators have main advantage in compared
with isotope irradiators in the operation.
The electrical power system allows to make flexible operation
with beam in compared with isotope source. The isotope
source is source of continuous irradiation.
Electron accelerators allows to work with low kinetic energy
(from few keV to hundred keV); it makes simple radiation
safety.
Electron accelerators in future can change the isotope
sources, that will make more safety and secure radiation
technologies.
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33. Conclusion
 The considered topic of introduction to
radiation technologies has education
and business goals.
 The radiation technologies present the
future of high technologies and our life.
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