Remon IbrahimRemon IbrahimHigh Energy GroupHigh Energy Group

IntroductionIntroduction

Experimental TechniquesExperimental Techniques

ResultsResults

ConclusionsConclusions

ContentContent

Flerov Laboratory of Nuclear reactions (FLNR)

FLNR carries out research in the field of heavy ion physics in three main directions

Radiation effects and modification of materials

The Irradiation Testing of Nuclear Ceramics and Oxides with The Irradiation Testing of Nuclear Ceramics and Oxides with

Heavy Ions of Fission Fragment EnergyHeavy Ions of Fission Fragment Energy

Dr. Vladimir Skuratov, D.ScDr. Vladimir Skuratov, D.Sc

IntroductionIntroduction

One concept to reduce the environmental impact of radioactive waste, is One concept to reduce the environmental impact of radioactive waste, is the use of inert matrix fuels, which consist of a fissile phase embedded the use of inert matrix fuels, which consist of a fissile phase embedded in an inert matrix phase. in an inert matrix phase.

Materials to be employed as inert matrices for transmutation of minor Materials to be employed as inert matrices for transmutation of minor actinides should be resistant to radiation damages caused by fission actinides should be resistant to radiation damages caused by fission fragments.fragments.

Such fission fragment-induced damage can be simulated by irradiation Such fission fragment-induced damage can be simulated by irradiation of swift heavy ions having the same stopping power.of swift heavy ions having the same stopping power.

The aim of this project is to study to radiation damage induced by swift The aim of this project is to study to radiation damage induced by swift heavy ions (E=1-3 Mev/amu) in several ceramics and single crystals heavy ions (E=1-3 Mev/amu) in several ceramics and single crystals (MgO, Al(MgO, Al22OO33, ZrO, ZrO22) in order to qualify them as candidates for inert ) in order to qualify them as candidates for inert

matrix fuel.matrix fuel.

IntroductionIntroduction

One useful method to study the radiation damages is the optical One useful method to study the radiation damages is the optical spectroscopy, namely the photoluminescence technique.spectroscopy, namely the photoluminescence technique.

In this technique the material is excited using light source and the light In this technique the material is excited using light source and the light emitted from the material (luminescence) is monitored at the typical emitted from the material (luminescence) is monitored at the typical emission frequencies. The luminescence spectra may provide information emission frequencies. The luminescence spectra may provide information about radiation defects in material.about radiation defects in material.

IntroductionIntroduction

Techniques

Microluminescence

Experimental Techniques

Laser confocal scanning microscope

The material used is LiF irradiated with Xe ions with the energy 1.2MeV/nucleon

Laserex. = 473 nm

Digital Camera

Spectrometer

31

4

5

2

1 – Specimen

2- Irradiated area

3- Piezo stage (1 step – 100 nm)

4 - Base

5- Lens

6

6 – Semitransparent mirror

7

7 – Filter

8

8 – Mirror Pinhole

LiF sample

Xe ions

Ion Range

Measuring area

The experimental The experimental ProcedureProcedure

Minimal size of analyzed area d=2.5 m for magnification 100. d= (0.1- 0.2)×Rp Rp - ion projected range

Photos of the stage micrometer for reflected light for different magnification 50 and 100. The distance between grooves – 10 m.

Spatial Resolution of optical system

analyzed area

Results of the test measurements

500 550 600 650 700 750 800 8500

10000

20000

30000

40000

50000

x=16 m

Pho

tolu

min

esce

nce

sign

al ,

a.u.

, nm

x=3 m

F+3 F2

Each peaks in this spectra represent

different types of F-center.

Irradiated area

50

Irradiated area Rp = 18 m

100

The peak at 530 nm corresponds to F3+ center

while 670 nm corresponds to F2 center

+e- F Center

e-

e-F2 Center

e-e-

F3+Center

Li+

F-

We measured the photoluminescence spectra at different depths for different fluences of Xe ions

Results of the test measurements

The luminescence signal at highest ion fluences is registered mainly from the end-of-range region

Results of the test measurements

Depth profiles of elastic (Sn) and ionizing (Se) energy losses

This reflects the contribution of ionizing and nuclear energy losses in damage formation processes in LiF

In most cases luminescence is sufficient to study the defects but in some cases In most cases luminescence is sufficient to study the defects but in some cases more detailed is needed. This can be done using Laser Confocal Scanning more detailed is needed. This can be done using Laser Confocal Scanning Microscope. Microscope.

This is a technique for obtaining high-resolution optical images with depth This is a technique for obtaining high-resolution optical images with depth selectivity.selectivity.

Images are acquired point-by-point and reconstructed with a computer, Images are acquired point-by-point and reconstructed with a computer, allowing three-dimensional imaging of objects.allowing three-dimensional imaging of objects.

Laser Confocal Scanning Microscope

We used LCSM with LiF samples and we get the same We used LCSM with LiF samples and we get the same depth profile as get by micro spectrometerdepth profile as get by micro spectrometer

This work demonstrates how we can use This work demonstrates how we can use photoluminescence spectra used to determine the photoluminescence spectra used to determine the defects induced by heavy ions (fission fragments).defects induced by heavy ions (fission fragments).

Also, the photoluminescence spectra can be used to Also, the photoluminescence spectra can be used to estimate the residual stress in solids caused by heavy estimate the residual stress in solids caused by heavy ion irradiation using the shift of characteristic ion irradiation using the shift of characteristic emission lines.emission lines.

ConclusionConclusion

I wish to express my sincere gratitude to my supervisor I wish to express my sincere gratitude to my supervisor

Dr. Vladimir Skuratov. Dr. Vladimir Skuratov. The supervision and support that The supervision and support that

he gave to me truly help the progression of my work.he gave to me truly help the progression of my work.

AcknowledgementAcknowledgement

I sincerely thank other staff members who rendered their I sincerely thank other staff members who rendered their

help during the period of my work. My special thanks to help during the period of my work. My special thanks to

Tatiana and NikitaTatiana and Nikita for their kind cooperation. for their kind cooperation.