This document discusses types of radiation, their interaction with matter, and radiation detectors. It covers the following types of radiation: photons (gamma rays and x-rays), neutrons, electrons, ions, protons, and alpha particles. It describes the processes of photoelectric effect, Compton scattering, and pair production for photon interaction, as well as scattering, capture and other interactions for neutrons. The document also discusses why radiation detection is important and gives examples of different types of radiation detectors like gas detectors, scintillation detectors, and semiconductor detectors.

1. TYPES OF RADIATION/INTERACTION
WITH MATTER/RADIATION
DETECTORS
Girish kumar Palvai
Website: www.conceptualphysicstoday.com
Email: palvaigirish@physicsdownloads.com

2. Topics under Discussion
 What is Radiation?
 Types of Radiation?
 Interaction of radiation with matter.
 Why Radiation Detection?
 Types of Radiation detectors
 Radiation Detectors in ECIL
 Radiation --- harmful to mankind?

3. Radiation could be referred to as flux of energetic
particles emanating from Nuclei /atomic events.
The word radiation in the present world covers both high
energy photons and energetic subatomic particles such
as electrons, protons, -particles, fission products etc.

4. Process of emission of energetic
subatomic/Nuclei particles due to change
in state of certain atoms/nuclei. Such nuclei
are called unstable nuclides.
This phenomenon is called Radioactivity.

5. Types of Radiation :
1. Uncharged Radiation ( Electromagnetic Radiation )
a) Photons (Gamma Rays & X-Rays )
b) Neutrons
2. Charged Particle Radiation :
a) Light Charge Particle – eg: Beta ( electron ), Positron
3H, 14 C
b) Heavy Charged Particle – eg :Alpha : 232Th, 238 U

7. Types of Radiations
Photons
Particles
Electromagnetic waves
X-rays gamma-rays Electron Ions Neutron
-ray Proton, -rays
EB
Commonly used Heavy ions
radiation sources

8. Cosmic Shower
~109-1021 eV (~ 6 GeV)
 (~ km)  (100mb)
2 x 1018 particles (mainly
protons) / s enter the
atmosphere
(ISOTROPIC)
Upto
~100
• Interact with atmospheric nuclei MeV
& produce secondary particles
(muons, electrons, photons,
neutrons: responsible for cosmic
dose) Flux %
H 1300 92.9
He 88 6.3
>He 10.7 1.06

9. S
o
u
r
The Neutron Sources
c
e
Cosmic radiations & High-energy particle
accelerators are well-known neutron sources
Cosmic rays: 2 types
High-Energy Particle
accelerators

10. CYCLOTRONS / SYNCHROTRONS /LINEAR ACCELERATORS

13. Interaction of Gamma Photons with matter
Photoelectric effect:
The kinetic energy Ee of the
photoelectron is given by
E e= hν–E b hν
The cross section for photoelectric
absorption depends on the atomic Ee
number (Z) of the absorber and
energy of the photon Eγ
σPE α Z4.5 / Eγ3
13

14. Compton scattering
The scattered photon energy is given by
E
Esc 
E
1 1 - cos  
m0 c 2
The cross section for Compton scattering is hν e
θ
σ cs α Z / Eγ
hν’
14

15. Pair Production
The excess energy above 1.02 MeV is shared between the positron
and electron as kinetic energy, which are later slowed down in the
stopping medium.
Eγ= e- + e+ + Ee- + Ee+
The cross section for pair production varies with Z of the absorber
and Energy of the photon as,
σ pp α Z2 ln Eγ
15

16. Relative Importance of Three Major Interaction
Mechanisms
16

17. Interaction of Neutrons with matter
• Charged particle emission (Slow neutrons)
• Elastic scattering collision (Fast neutrons)
• In elastic scattering collision (Fast Neutrons)

18. Slow Neutrons Interaction
10B + 0n1   (5B11)   (3Li7 )+++ + (2He4 )++ + 2.34 Mev

19. Fast Neutron Interaction
In- Elastic scattering: -
Excited Compound
Nucleus
Emitted Neutron
Incident
Neutron
Gamma Ray
Target nucleus

20. Elastic scatter:
• The neutron and the nuclide collide and share a part of their kinetic
energies. They rebound with speeds different from the original speeds,
such that the total kinetic energy before and after the collision remains
the same. If the nucleus is stationary before collision, it will gain energy
from the neutron and start moving, and the neutron gets slowed down
due to loss of kinetic energy. However, the residual nucleus is not excited
but is in its ground state.
• The most important process for slowing down of neutrons.
• Total kinetic energy is conserved
• E lost by the neutron is transferred to the recoiling particle.
• Maximum energy transfer occurs with a head-on collision.

21. Non elastic scatter
• Differs from inelastic scattering in that a secondary
particle that is not a neutron is emitted after the
capture of the initial neutron.
eg: 12C ( n, α ) 9Be ; Egamma = 1.75 MeV
• Energy is transferred to the alpha particle and the
de excitation gamma ray.

22. Neutron capture
• Same as non elastic scatter, but by definition, neutron capture
occurs only at low neutron energies (thermal energy range is <
0.025 eV).
• Capture leads to the disappearance of the neutron.
• Neutron capture accounts for a significant fraction of the energy
transferred to tissue by neutrons in the low energy ranges.
eg: 1H ( n, gamma ) 2H ; Egamma = 2.2 MeV
Spallation
• In this process, after the neutron is captured, the nucleus
fragments into several parts. Only important at neutron energies in
excess on 100 MeV. (cross sections are higher at 400-500 MeV).

23. Why to detect Radiation?
&
How to detect Radiation

24. Why to detect Radiation?
• Environmental safety
• Personal protection of occupational workers
• Calibration of radioactive isotopes
• Power regulation in nuclear reactors
• Research applications
• Estimation of radiation dose in treatment of
patients and more…………….

25. How to detect Radiation?
Choose a radiation detector working on a particular
principle of interaction (ionization/scintillation/etc)
with known sensitivity to estimate the radiation under
detection.

26. Some Characteristics of Radiation Detectors
• Sensitivity
• Operating voltage
• Operating voltage region
• Radiation detection range
• Resolution (for pulse based)
• Less dead time
• Life time

27. TYPES OF RADIATION DETECTORS
Gas Flow Scintillation Semi-Conductor
Detectors Gas Filled
Detectors Detectors Radiation
Detectors
Alpha Beta Gamma Neutron Other Particles
Detectors Detectors Detectors Detectors & Energy GM
Radiation

28. GEIGER MULLER TUBE

29. GM Tube Plateau Characteristic

31. GEIGER MULLER TUBE

32. GAS FILLED DETECTORS
Gamma Ion Chamber Gamma Ion Chamber B10F3 filled counter.
Criticality Alarm Systems Area Monitoring He3 filled counter.
Neutron Monitoring
Fission Detector with MI Fission Detector with MI Neutron Monitoring
cable for Source Range Self Powered Neutron Detector
cable for Intermediate
Monitoring ( BWR) Range Monitoring( BWR) Gamma Compensated neutron
Ion chamber
Uncompensated Neutron Ion
Chamber with MI cable for Power
Range Monitoring in PHWRs

34. Neutron Detectors
Fission Detectors
B10 Lined Proportional Counters
BF3 Proportional Counters
He3 Proportional Counters
B10 Coated Ion chambers
Self Powered Neutron Detectors (SPND)

35. B10 Lined Proportional Counters
 Application: Used normally for physical or
normal start-up of Reactors.
 Sensitivity From 0.8 to 20 CPS/nV
 4 CPS/nV detectors are supplied regularly to
NPCIL for Reactor Start-up
 Enriched Boron (96% enriched amorphous fine
powder) is the main constituent.
10B + 0n1   (5B11)   (3Li7 )+++ + (2He4 )++ + 2.34 Mev

36. B10 Coated Ion chambers
 Supplied regularly to NPCIL for Reactor Power
Measurement in Intermediate and Power Range
 Sensitivity:
Neutron: 10-14 Amps/nv,
Gamma: 10-11 Amps/R/hr (Un Compensated)
10-12 Amps/R/hr (Compensated)

37. B10 coated Ion chamber with integral MI cable assembly
 Boron-10 coated chamber with integral MI cable assembly
 Neutron Sensitivity: 1x10-14 Amps/nv
 Gamma Sensitivity: 2.5 x10-12 Amps/R/h
 Range: 104 to 1011 nv
 Operating Voltage: 600 V
 Operating Temperature: 100 deg C
 Dimensions: 88 mm dia, 330 mm length,

38. 10BF Gas Filled Detectors
3
 Sensitivity from 4 to 150 CPS/nv
 25 CPS/nv detectors are supplied regularly to NPCIL,
BARC for DNM and other systems
 Enriched Boron Complex (B10 F3 CaF2 ).. 90% enriched
powder) is the main conversion material to generate
BF3 Gas by thermal decomposition.
 B10 F3 CaF2 complex currently produced by HWB
Generation and purification system is made by ECIL

39. He3 Detectors
 Sensitivity from 10 to 250 CPS/nv
 Applications: SNM detection
systems, research applications etc.
 Supplied to IGCAR, BARC for Neutron well
counters and other applications

41. Fission Detectors
• HEU based
 SRM, IRM, LPRM, Wide Range
 Sensitivity From 10-3 to 1 CPS/nv, With & Without
integral MI Cable
 Supplied to BWR, FBTR
• LEU (<20% Enrichment) based
 Sensitivity From 10-3 to 0.18 CPS/nv, With & Without
integral MI Cable
 Supplied to BARC, PHWR
 High Temperature (650o C) Fission Counter for PFBR

42. FD for Source Range Monitor
Used for incore flux monitoring in BWRs.
 Pulse mode operation
U-235 (90% enriched) coated counter with integral MI cable assembly
 Sensitivity: 10-3 CPS/nv
 Range: 104 to 109 nv
 Operating Voltage: 350 V
 Operating Temperature: 300 deg C
 Dimensions: 6 mm dia, 75 mm length, sensitive length: 25 mm

43. Local Power Range Monitor
 U-235 (90% enriched) coated chamber with integral MI cable assembly
 Neutron Sensitivity: 1x10-17 Amps/nv
 Range: 1011 to 1013 nv
 Gamma Sensitivity: Less than 5x10-14 Amps/R/h
 Operating Voltage: 100 V
 Operating Temperature: 300 deg C
 Dimensions: 6 mm dia, 75 mm length, sensitive length: 25 mm

44. Self Powered Neutron Detectors
 Sensitivity: 10-22 Amps/nv
 Operating temperature: Up to 3000C
 Emitter: Cobalt, Vanadium, Platinum
 Supplied regularly to NPCIL for Incore Flux Mapping
 Fabricated with Integral MI Cable
 Tested for hydrostatic pressure of 250 kg/cm2

45. SPND with COBALT EMITTER
SPND with VANADIUM EMITTER

46. Gamma Detectors

47. Gamma Detectors
Gamma Ion Chambers
• CRITICALITY-CAS-G11;
• AREA MONITORING-G12, 12A;
• ISOTOPE CALIBRATION- well type-G13;
• ENVIRONMENTAL RADIATION MONITORING-G15,
G17
• FUEL FAILURE DETECTION, DHRUVA , BARC-G20,
G21

48. • Application: Criticality Alarm System
• Gamma Field range: 1mR/hr to 1000R/hr
• Sensitivity : 3 x 10-10 A/R/Hr
• Fill gas: Nitrogen + Argon
• Seismic qualified

49. • Application: Shut Down Area Range Monitor
• Gamma Field range: 1mR/hr to 1000R/hr
• Sensitivity : 4.5 x 10-9 A/R/Hr
• Fill gas: Nitrogen + Argon
• Seismic qualified

50. • Application: Wide Range Gamma Monitor
• Gamma Field range: 100 mR/hr to 104 R/hr
• Sensitivity : 1.0 x 10-10 A/R/Hr
• Fill gas: Nitrogen + Argon
• Seismic qualified

51. GAMMA IONISATION CHAMBER #G12 & #G12A for SHUTDOWN
AREA RADIATION MONITOR &
WIDE RANGE GAMMA RADIATION MONITOR for PHWR
APPLICATIONS

52. Whether Radiation is beneficial?

54. Dose ~ altitude
Cosmic ray Dose
versus altitude
NEUTRON SPECTRUM: HIGH
ALTITUDE ~ H*(10) ALTITUDE

55. Spectra:
Accelerator &
High-altitudes
Flight route
100 mSv 100 mSv
Measurements:
Dedicated &
passenger flights.

56. Nuclear Reactors
KAPS1& 2 NAPS1 & 2
RAPS 1 to 6
TAPS 3 & 4
KGS 1 to 4
KKNPP 1&2 MAPS 1 & 2
(56)

59. CANCER TREATMENT OUTCOMES
55% 45%
PRESENTLY SUCCESSFULLY
INCURABLE CURED
Chemotherapy
Uncontrolled
5% Surgery
Metastases
22%
37%
Radiotherapy
Uncontrolled Surgery & 12%
Primary Tumor Radiotherapy
18% 6%
59

60. EYE TREATMENTS
fixation light

61. Applications of Radiation Technology
 Crosslinking of polymers
 Degradation of high molecular weight materials
 Curing of polymer coatings
 Graft polymerization
 Sterilization of medical products
 Food irradiation
 Sewage Sludge Hygienization

62. Thank You
for
your
patience