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Parametric X-rays: ready for application

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PARAMETRIC X-RAYS:
READY FOR APPLICATION
R esea rch In stitu te
fo r N u clea r P ro b lem s
Alexander LOBKO
Institute for Nuclear Problems,
Belarus State University
Minsk
IX Gomel School - July 2007
Light sources
nanoscience
http://www.lightsources.org/cms/?pid=1000166
2
Spectral brilliance of T- & x-ray sources
There is a large gap between
properties of common and
accelerator-based x-ray sources
X-rays: The First Hundred Years // Wiley 1996
3
Typical size of a contemporary
synchrotron
4
Budget of the SOLEIL synchrotron
(France)
Construction
? Investment?????.235 M?
? Operation??????..64 M?
? Salaries???????.150 M?
Total??????????.449 M?
Yearly?????????...53 M?
www.synchrotron-soleil.fr
5
Synchrotron sources in the world
About 40 sources in 20 countries
USA
8
Germany
5
Japan
5
China
3
France
3
UK
2
Russia
1
http://www-als.lbl.gov/als/synchrotron_sources.html
6
Comparison of some x-ray generation
processes at accelerators
BR
Yield,
photon/e
1.2*(-8)
Е,
MeV
500
CBR
1.7*(-7)
0.2
SR
1.2*(-5)
3 *(+3)
TR
1.0*(-9)
125
RR
1.6*(-7)
50
PXR
1.3*(-5)
50
Type of radiation
V.G. Baryshevsky, I.D. Feranchuk // NIM 228 (1985) 490
7
Parametric x-rays (PXR)
?p
2
n (? ) ? 1 ?
?
?
2?
?1
2
1 ? vn k ? ? cos ? ? 0
Condition for the Cherenkov radiation emission
?n?
?B ?
? cn
d sin ? B
k? ? k ??
2
?
?
? Nn
? N ПРИ
? F ? eQ , ? , g 0 ,? , ? B , ? s , L , T , ? , ? , X 0 ,
, ... ?
? ? ??
? ? ??
?
?
2
V. Baryshevsky, I. Feranchuk, A. Ulyanenkov Parametric X?ray Radiation in
Crystals: Theory, Experiment and Applications // Springer, 2006. ? 176 p.
8
PXR experiments in the World
? Armenia ? Erevan ErPI LINAC
? Belarus ? INP in collaborations with Tomsk & IHEP
Protvino & Mainz, own experiments with nonrelativistic electrons
? Canada ? Saskatchevan Accelerator Lab LINAC
? Germany ? Darmstadt S_DALINAC, Mainz MAMI
Microtron, Rossendorf ELBE LINAC
? Japan ? Tokyo U. Synchrotron, Tohoku U. LINAC,
Hiroshima U. LINAC, Kamigori Spring-8
Synchrotron, Kyoto U. LINAC, Hokkaido U.
LINAC, Nihon U. LINAC
? Russia ? Tomsk SIRIUS Synchrotron, Dubna JINR
Nuclotron, Belgorod U. in collaborations
? Ukraine ? Kharkov KPTI LINACs
? USA ?
RPI LINAC, BNL Accelerator Facility LINAC,
9
Naval Postgraduate School LINAC
Main PXR features
? it is quasi-monochromatic x-ray radiation
? x-rays energy can be changed
continuously by the crystal target rotation
? it is directed and polarized x-ray radiation
? x-rays energy does not depend on energy
of incident charged particles
? radiation angle can be as large as
180 arc degrees
10
Applications of synchrotron radiation
11
Soft X-Ray Imaging
Methods: Soft x-ray imaging, photoelectron emission
microscopy (PEEM), scanning transmission x-ray microscopy
(STXM), full-field microscopy, x-ray diffraction imaging (XDI),
x-ray tomography, computer-aided tomography (CAT).
Problems:
Cell biology
Nano-magnetism
Environmental science
Soft matter, polymers
The tunability of radiation is absolutely essential
for the creation of contrast mechanisms.
12
Soft X-Ray Spectroscopy
Methods: Soft x-ray absorption spectroscopy (XAS), near-edge
x-ray absorption fine structure (NEXAFS) spectroscopy, soft xray emission spectroscopy (SXES), resonant inelastic x-ray
scattering (RIXS), x-ray magnetic circular dichroism (XMCD),
x-ray photo-emission spectroscopy (XPS), Auger
spectroscopy.
Problems:
Complex materials
Magnetic materials
Environmental science
Catalysis
The photon energy tunability and its brilliance and
polarisation for some applications are essential.
13
Soft X-Ray Scattering
Methods: Soft x-ray emission spectroscopy (SXES), inelastic
x-ray scattering (IXS), resonant x-ray inelastic scattering
(RIXS), speckle patterns, small-angle x-ray scattering (SAXS).
Problems:
Strongly correlated materials
Magnetic materials
Environmental science
Catalysis
The tunability of radiation and its brilliance for
some applications are essential.
14
Practical examples of PXR applications
Nihon University, Japan
enhanced contrast images
EXAFS
15
Rensselaer Polytechnic Institute, NY, USA
PXR source based on the tabletop
synchrotron
Photon Production Laboratory
Japan
16
First observation of parametric rays in
the microwave range
exiting (slow-wave) grating
step ? 0,67 мм
10
8
6
4
2
3
8
0
6
6
4
-2
2
15 мкс
0
0
-4
Сигнал СВЧ диода, В
Энергия пучка, кэВ
6
diffraction (feedback) grating
step ? 3 мм
-2
-4
0
-6
-6
-6
21,66
21,72
18
Время, мс
21,78
-8
21
NIM A 483 (2002) 21?23;
NIM A 507 (2003) 137?140
17
Possible T-rays applications
18
http://www.lightsources.org/cms/?pid=1000680
Thank you for attention
19
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