ESR in dosimetric and dating applications

Transcript

The role of Electron Spin Resonance (ESR)
spectroscopy in dosimetric and dating applications
Dott. Maurizio Marrale
Università degli Studi di Palermo
Dipartimento di Fisica e Tecnologie Relative
Invited contribution
Società Italiana di Fisica
XCVI Congresso Nazionale
Bologna, 20 - 24 Settembre, 2010
M. Marrale – ESR in dosimetric and dating applications
OUTLINE
XCV Congresso Nazionale SIF Bologna 20 - 24 Settembre 2010
OUTLINE
 ESR DOSIMETRY
OUTLINE
 ESR DOSIMETRY
 ALANINE/ESR DOSIMETRY
 ESR DOSIMETRY WITH OTHER COMPOUNDS
 RADIOTHERAPEUTIC APPLICATIONS
 DOSIMETRY AT CERN
 RETROSPECTIVE DOSIMETRY
 LET DISCRIMINATION
 CONTROL OF IRRADIATED FOOD
OUTLINE
 ESR DOSIMETRY
 ALANINE/ESR DOSIMETRY
 ESR DOSIMETRY WITH OTHER COMPOUNDS
 RADIOTHERAPEUTIC APPLICATIONS
 DOSIMETRY AT CERN
 RETROSPECTIVE DOSIMETRY
 LET DISCRIMINATION
 CONTROL OF IRRADIATED FOOD
 ESR DATING
A little bit of history...
A little bit of history...
Regulla D. F. Appl. Radiat. Isot. 62 (2005) 117–127
ESR applied for dosimetric applications
Energy released
in matter
Absorbed dose
Number of paramagnetic
centers produced by
ionizing radiations
(i.e. free radicals, point
defects, etc)
Energy released
in matter
ESR
Dosimetry
Absorbed dose
centers produced by
ionizing radiations
defects, etc)
Energy released
in matter
Absorbed dose
ESR
Dosimetry
The readout does not
affect the ESR signal
 additive dose response
centers produced by
ionizing radiations
defects, etc)
 repeated readings
distinguishing
EPR/alanine dosimetry
from most other forms of
dosimetry
Methods to evaluate dose
Construction of the
calibration curve
I
D
Construction of the
calibration curve
I
D
Additive dose
method
Extrapolated
dose value
ESR dosimetry
ESR dosimetry
Alanine dosimetry
ESR dosimetry
Alanine dosimetry
The alanine at present it is formally accepted by
IAEA (International Atomic Energy Agency, Vienna, Austria)
NIST (National Institute for Standards and Technology, USA) and
NPL (National Physical Laboratory, UK)
as a secondary reference and transfer dosimeter for high dose
irradiation.
Alanine dosimeters features
 The linearity of the EPR response in a wide range of doses from 10 up to 5×104 Gy.
 The linearity of the EPR response in a wide range of doses from 10 up to 5×104 Gy.
ESR/alanine dosimetry
The amino acid alanine:
• near tissue equivalence
• high radiation chemical yield
• near invariant response to
 variations in photon energy
 minor temperature variations
 other variations in ambient conditions
ESR/alanine dosimetry
The amino acid alanine:
• near tissue equivalence
• high radiation chemical yield
• near invariant response to
 variations in photon energy
 minor temperature variations
 other variations in ambient conditions
• high stability of radiation products
Sagstuen et al. J Phys. Chem. A 1997, 101, 9763-9772
 Sufficiently small size for use in mapping radiation dose distribution;
 Ruggedness and ease of handling;
 Low cost for individual dosimeter samples.
Pellets
Strips
Rods
ESR instrumentation
A commercial 9 GHz
System (X-band)
Portable ESR dosimeter readers
Aérial ESR
Dosimetry Equipment
High Sensitive Benchtop
EPR Spectrometer MiniScope
MS 200
Bruker e-scan
Specific applications:
•
Alanine dosimetry
•Food control
•Beer control
Applications in radiotherapeutic field
Measurements on anthropomorphic phantom
In vivo measurements
Applications for radiation therapy:
Brachitherapy for prostate cancer

Brachitherapy for uterus cancer

Therapy for breast cancer


D. Wagner et al. Radiotherapy and Oncology 88 (2008) 140–147
...
In vivo measurements
The ESR dosimetry is
aided by direct readout
instrumentation such as
SC diodes
Applications for radiation therapy:
Brachitherapy for prostate cancer

Brachitherapy for uterus cancer

Therapy for breast cancer


D. Wagner et al. Radiotherapy and Oncology 88 (2008) 140–147
...
Alanine ESR proton dosimetry
pellets
Onori et al. Med. Phys.
1997 24 (3) 447-453
Alanine ESR proton dosimetry
Onori et al. Med. Phys.
1997 24 (3) 447-453
films
Palmans, Technol Cancer Res Treat.
2003 Dec;2(6):579-86
Sensitivity:
• best lower dose limit for obtaining sD < 3% : D = 2-3 Gy
(Nagy et al., Appl. Radiat. Isot. 56, 917 (2002))
• limited by extensive hyperfine coupling, orientational dependencies
and background signals
• too low for many low-dose applications
Sensitivity:
• best lower dose limit for obtaining sD < 3% : D = 2-3 Gy
(Nagy et al., Appl. Radiat. Isot. 56, 917 (2002))
• limited by extensive hyperfine coupling, orientational dependencies
and background signals
• too low for many low-dose applications
Searching for alternative materials
• retaining the excellent dosimetric properties of alanine
• better dosimetric sensitivity than alanine
Alternative materials
Factors to be taken into accout:
EPR spectrum
Radiation chemical yield of radicals
Stability of radiation-induced radicals
Power saturation properties
Radiation quality dependence
Dose/dose rate dependence
Robustness
Ammonium tartrate
Ammonium tartrate
S.K. Olsson et al. Appl. Radiat.Isot. 50, 1999, 955-965
Lithium formate
molecular structure:
HCOO- Li+
Lund et al. Appl.Radiat. Isot. 62, 2005, 317-324
Peak-to-peak amplitude per mass (arb. units)
Lithium formate
250
Alanine
Lithium formate
200
150
100
50
0
0
2
4
6
8
10
12
Dose (Gy)
Peak-to-peak amplitude per mass (arb. units)
Lithium formate
250
Other compounds:
 sugar
 aminoacids
 acetates
 phosphates and lactates
 anhydrous MgSO4
 acids with sulfur
 barium sulphate
 ferrous ammonium sulfate
 alkaline-earth metal
dithionates
Alanine
Lithium formate
200
150
100
50
0
0
2
4
6
8
10
12
Dose (Gy)
IMPROVEMENT OF THE ESR SENSITIVITY
 CHOICE OF ADDITIVES WITH SUITABLE
PROPERTIES
 CHOICE OF ADDITIVES WITH SUITABLE
PROPERTIES
FOR EXAMPLE: DOSIMETRY IN A MIXED (n,γ) FIELD
157
Gadolinium: σth( Gd) ~255000 barn
σth∝µ
σth(N) ~ 1.83 barn
Neutron irradiations
(50%-50%)
The
gadolinium
addition
improves the
neutron
sensitivity to
about a
factor 30.
Brai et al. Phys. Med.
Biol. 52, 5219 (2007).
Analysis of the response vs additive concentration
Marrale et al. Radiat.
Meas. 43, 471 (2008)
ESR dosimetry for
LHC (2 x 7 TeV)
Accelerators at
CERN
(high-energy part)
Super Proton Synchrotron
(450 GeV/c)
1 km
High level dosimeters at LHC
Forecast of damage and required replacement of equipment.
Example: Monitoring of dose
in the Super Proton Synchrotron
(SPS)
Dosimeter
position at cables
Dosimeter position
at coils
Schönbacher et al.
High Level Dosimetry. 2010
ESR dosimetry at CERN - Experiment at CERF in 2003
Mixed hadron beam
Momentum
Total intensity
60% π+, 35% p, 5% K+
120GeV/c
1.55×1012
Al2
beam
Al1
Schönbacher et al.
XCV Congresso Nazionale
Settembre
2010
RPL 3SIF Bologna
RPL 2 20 - 24 RPL
1
RPL 4
ESR dosimetry at CERN -- Experiment at CERF in 2003
Monte Carlo Simulations
Schönbacher et al.
ESR dosimetry at CERN -- Experiment at CERF in 2003
Comparison of experimental data with Monte Carlo Simulations
Schönbacher et al.
High Level
XCV Congresso Nazionale SIF Bologna 20 - 24 Settembre
2010Dosimetry. 2010
Retrospective dosimetry
It aims at reconstruct absorbed dose in cases of accidental
or protracted radiation exposure
Retrospective dosimetry
It aims at reconstruct absorbed dose in cases of accidental
or protracted radiation exposure
(natural and
synthetic)
Dust
EPR Biodosimetry (Teeth)
Hydroxyapatite constitutes:
~95% by weight of tooth enamel
70-75% of dentin
60-70% of compact bones
Romanyukha, et. al, Appl. Radiat. Isot. (2000) and IAEA-TECDOC-1331
EPR biodosimetry in tooth enamel for partial body dose
assessment
X-band EPR is ready to use for forensic dose assessment.
Could be carried out on compact and transportable (< 150 kg)
EPR spectrometer. Dose level <100 mGy.
A. Romanyukha et al. EPR biodosimetry in teeth and fingernails.
EPR biodosimetry in tooth enamel for partial body dose
assessment
X-band EPR is ready to use for forensic dose assessment.
Could be carried out on compact and transportable (< 150 kg)
EPR spectrometer. Dose level <100 mGy.
 Q-band biopsy potentially is able to measure doses < 500 mGy
in biopsy tooth enamel samples 2-4 mg.
Whole
Tooth
Biopsy
EPR biodosimetry in tooth enamel for partial body
dose assessment
L-band in vivo EPR potentially is able to measure doses as low as 3
Gy. Needs some additional development.
EPR biodosimetry in tooth enamel for partial body
dose assessment
L-band in vivo EPR potentially is able to measure doses as low as 3
Gy. Needs some additional development.
EPR Biodosimetry Applications
SOUL (Southern Urals
Radiation Risk Research)
Project aimed at analyzing
the effects on health of
long-term exposure to
low-dose levels of
radiations
Science vol 310
11 November 2005
Dose assessment in case of accident

Clinical observations: symptomatology


Biological dosimetry: biochemical parameters, etc.



Physical dosimetry:
• Dose reconstruction using
experimental tools
Clairand I. Dose reconstruction in case of radiological
accidents. Workshop on dosimetry, May 19, 2010
SCK·CEN, MOL, BELGIUM



Physical dosimetry:
experimental tools
numerical tools



Physical dosimetry:
experimental tools
numerical tools
• Dose measurement on
irradiated materials via ESR
Accidental retrospective dosimetry
Clairand I. Dose reconstruction in case of radiological accidents. Workshop on dosimetry, May 19, 2010 SCK·CEN, MOL, BELGIUM
LET discrimination in various fields
Space research
(Astronauts are exposed to:
Galactic Cosmic Rays
Solar Wind
Coronal Mass Ejections)
Space research
Solar Wind
Radiation therapy
Space research
Solar Wind
Radiation therapy
Dosimetry in cases of accidental release of radioactive
isotopes
(e.g. Chernobyl)
Free radicals distributions for radiations with
various LETs
Small local concentration
of free radicals
Low LET radiation
electrons
High LET radiation
High local concentration
of free radicals
Local microscopic concentration of free radicals
AVERAGE EFFECTIVE LET
~ 0.35 keV/µm
~ 4.5 keV/µm
~ 70 keV/µm
M. Marrale, M.
Brai, A. Barbon,
M. Brustolon
Radiat. Res.
2009, 169, 349359
Distance distributions of free radicals
The distance distributions for
dosimeters of AT exposed to gamma
photons (red curve) exposed to
thermal neutrons are similar to the
simulation
with
isotropic
3D
distribution of spins.
The
distance
distribution
for
dosimeters exposed to protons (blue
curve) shows a peak which is related
to the size of the track of these heavy
charged particles.
M. Marrale, M. Brai, A. Barbon,
M. Brustolon Radiat. Res.
2009, 169, 349-359
Control of irradiated food
Control of irradiated food
Three current methods, internationally recognized,
used to identify irradiated foods by means of ESR
 Detection of irradiated food containing bone Method by ESR spectroscopy [EN 1786:1996]
 Detection of irradiated food containing cellulose.
Method by ESR spectroscopy [EN 1787:2000]
 Detection of irradiated food containing crystalline
sugar by ESR spectroscopy [EN13708:2001]
ESR dating
ESR dating
cosmic
rays
e.g. quartz
grain/coral/
mollusc
shell
ESR dating in earth sciences and
achaeology refers to the effect
of accumulated radiation in a
mineral relative to time.
Paramagnetic centres are detected
in the crystal lattice of the mineral by
means of ESR technique.
Thorium
Uranium
Potassium
http://www.geomorph.uni-bayreuth.de/de/ressourcen/lehrmaterialien/Zoeller/d9_Principles_of_esr_dating.ppt
EXAMPLE OF ESR DATING
EXAMPLE OF ESR DATING
Homo Neanderthalensis
Rink W. J. et al Nature 378, 24 (2 November 1995)
www.anthro.ucdavis.edu/faculty/mchenry/Ant152/A15214.pdf
•
•
ESR middle earth
Gaseous phase
ESR
Spin labels
Transition Metals
ESR
ESR dosimetry
and dating
In vivo ESR
Spin Trap
ESR middle earth
Gaseous phase
ESR
Transition Metals
ESR
Thanks for your kind
attention!!!
Spin labels
ESR dosimetry
and dating
In vivo ESR
Spin Trap

ESR in dosimetric and dating applications

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