Download Channeling Projects at Frascati - CARE-HHH

CHANNELING projects at LNF:
From Crystal Undulators to Capillary Waveguides
Sultan Dabagov
CC-2005, CERN, 8 March 2005
Channeling: Orientational Effects of Transmission & Radiation
• 1962-63:
Robinson &
Oen:
Prediction of anomalous penetration
Piercy &
Lutz:
Experimental discovery
• 1965:
Lindhard:
Theoretical description
…..
Andersen
Uggerhoj
Classical theory
Kagan
Quantum theory
Kononez
Prediction of channeling radiation (ChR)
Firsov
Tsyganov
Experimental confirmation: positron channeling in diamond crystal
Gibson
USSR-USA collaboration, SLAC 1978
Kumakhov JETP Lett. 1979 (Miroshnichenko, Avakyan, Figut, et al.)
Beloshitsky
Gemmel
Rev. Mod. Phys. 1974: 1 MeV e- @ Cu crystal
Appleton
…..
more than 1000 articles + a number of monographs
Channeling of Charged Particles
@ Amorphous:
@ Channeling:
Atomic crystal plane
planar channeling
e+
eAtomic crystal row (axis)
axial channeling
e
  1
(   L ~ U
E
)
- the Lindhard angle is the critical angle for the channeling
Channeling: Continuum model
V r  
screening function of Thomas-Fermi type
2
Z1Z 2e
 r a 
r

a  .8853a0 Z11/ 2  Z 21/ 2

2 / 3
screening length
 r a  :
3

i 1
i
exp   i r a 
 Ca 
1  1  2 
 r 
Molier’s potential
1 / 2
C 2  3 Lindhard potential
…… Firsov, Doyle-Turner, etc.
Lindhard:
Continuum model –
continuum atomic plane/axis potential

1
VRS     V
d 

2

 x 2 dx
Channeling:
X-Rays and Neutrons
X-ray and neutron capillary optics
@ Basic idea of polycapillary optics is
very close to the phenomenon of charged
particle channeling
X-ray Channeling: samples of capillary optics
1st generation:
[m]
2d generation:
[cm]
3d & 4th generations:
[mm]
http://www.unisantis.com
http://www.iroptic.com
5th generation:
[mm]
?n-capillaries?
Quantum base

1st order:  r   0 - no roughness
d
q
q  1
k   kq
k
Wave equation:
   k
d r  k Er   0


2
2

2


Veff
  
k 2d
k 2 d r  q 2 
plane
(flat)
surface
  k 2q 2 ,
r  r1
 2
2
k
d

q
,
r  r1
0






Total external reflection
Veff  0  q c  q  d 0
Quantum base (2) - curvature
approximation
simplification
additional term to
 k 2 r
2
rcurv
Veff
 
“potential energy”:
angular momentum of photon

r 
2

Veff  k  d r   q  2
rcurv 

2
krcurv
Surface channeling - “whispering X gallery”
continuum
S
discrete
* Whispering:
wall
Modes of channeling along curved surfaces
Effective guide channel
J.Synchrotron. Rad. 1995
Phys. Lett. A 1995
Down to bulk photon and neutron channeling
l
mm
q  1 (q c ~ 10 3 )
l 
l  l
d 0 ~ 1mm  10mm :
l  d 0
: grazing incidence optics
: from nm to mm
: surface channeling
l
nm
q d  l d 0 ~ q c : diffraction angle approaches Fresnel angle
: bulk channeling
l d 0 ~ 1
Ne
Usp. Fiz. Nauk – Physics Uspekhi 2003
Nanotubes: continuum potential example
Nanosheet CC
Base:
fullerene molecule C60
sphere of d ~ 0.7 nm
Roled graphite sheets:
nested nanotubes
Potentials: Doyle-Turner approximation
- form-factor for the separate fullerene
dR

continuum potential
as sum of row potentials
r – distance from the tube
I0(x) – mod. Bessel function
Phys. Lett. A250 (1998) 360
NIM B143 (1998) 584
X-Ray channeling in nanotubes
Channeling:
Electrons and Positrons
Channeling Radiation & Coherent Bremsstrahlung
MAMBO
+
FEL project at Frascati
Source
Pulsed
Self
Amplified
Radiation
Coherent
Self-Amplified Pulsed Coherent Radiation Source
Channelling
Channeling Radiation…
@ Channeling Radiation:
 fi
   (q ) 
1  || cos q
 fi - optical frequency
Doppler effect
Powerful radiation source of X-rays and -rays:
•polarized
•tunable
•narrow forwarded
 0 3 / -2  0 2
  1
Bremsstrahlung & Coherent Bremsstrahlung vs Channeling Radiation
@ amorphous - electron:
•Radiation as sum of independent impacts with atoms
•Effective radius of interaction – aTF
•Coherent radiation length lcoh>>aTF
•Deviations in trajectory less than effective radiation angles:
q  aTF / p
Nph
Quantum energy
Bremsstrahlung & Coherent Bremsstrahlung vs Channeling Radiation
@ interference of consequent radiation events:
phase of radiation wave
Radiation field as interference of radiated waves:
Coherent radiation length can be rather large even for short wavelength
@ crystal:
d
Nph
Quantum energy
Bremsstrahlung & Coherent Bremsstrahlung vs Channeling Radiation
 0
@ crystal:
d
channeling
ChR
  1/ 2 Z  2 / 3
B
B:
at definite conditions channeling radiation can be significantly powerful
than bremsstrahlung
CB:
ChR:
N  lcoh   2 / 
NZe
 NZ
2
 NZ 
2
 N eff Z 
2
Neff
Channeling Radiation vs Thomson Scattering

ChR
lab
2 2
ChR


0
1  q 2 2
- radiation frequency -
  3/ 2
 dN ph 

   1/ 2
 dt ChR
 2
- number of photons per unit of time -
P2
- radiation power -
 dN ph 

  Const
 dt TS
P2
@ comparison factor:
Laser beam size & mutual orientation
@ strength parameters – crystal & field:
By Carrigan R. et al.
Channeling Radiation vs Thomson Scattering
For X-ray frequencies: 100 MeV electrons channeled in 105 mm Si (110) emit ~ 10-3 ph/ecorresponding to a Photon Flux ~ 108 ph/sec
ChR – effective source of photons in very wide frequency range:
• in x-ray range – higher than B, CB, and TS
• however, TS provides a higher degree of monochromatization and TS is not
undergone incoherent background, which always takes place at ChR
Electron Beam Parameter list
Electron Beam Energy (MeV)
155
Bunch charge (nC)
1.1
Repetition rate (Hz)
1-10
Cathode peak field (MV/m)
120
Peak solenoid field @ 0.19 m (T)
0.273
Photocathode spot size (mm, hard edge radius)
1.13
Central RF launch phase (RF deg)
33
Laser pulse duration, flat top (ps)
10
Laser pulse rise time (ps) 10%90%
1
Bunch energy @ gun exit (MeV)
5.6
Bunch peak current @ linac exit (A) (50% beam
fraction)
100
Rms normalized transverse emittance @ linac exit
(mm-mrad); includes thermal comp. (0.3)
<2
Rms slice norm. emittance (300 mm slice)
< 1
Rms longitudinal emittance (deg.keV)
1000
Rms total correlated energy spread (%)
0.2
Rms incorrelated energy spread (%)
0.06
Rms beam spot size @ linac exit (mm)
0.4
Rms bunch length @ linac exit (mm)
1
Experimental scheme
Channelling
MAMBO
“Channeling” line layout
by Kharkov group
SPARC & SPARX & SPARXINO
SPARC
R&D program towards high brightness e-beam & SASE-FEL experiment
150 MeV e- : l ~ 500 nm 
SPARX Phase I - SPARXINO
R&D towards an X-ray FEL-SASE source ( 1.25 GeV : l < 10 nm )
S ource
P ulsed
Self
A mplified
R adiation
X
Self-Amplified Pulsed X Radiation Source
SPARX
(2.5 GeV e- : l = 13.5 – 1.5 nm)
SPARX-ino proposal
SPARC Injector + DAFNE Linac
SPARX-ino
a 5-10 nm SASE FEL source at LNF
SPARX-ino proposal
• upgrade the DAFNE Linac
to drive a 5-10 nm SASE-FEL
(available budget 15 M€)
• Beam energy : 1.2 - 1.5 GeV
• upgrade the injector to a RF
photo-injector (SPARC-like)
• Study group will prepare
a proposal within 2005
SPARC & SPARX & SPARXINO
- The SPARC project engineering has been completed
- The LINAC is entering, on schedule, the installation phase
- First beam delivery in 2006
- The SPARX project has been funded
- With an up-grade of Dafne Linac the region of a few nm
would be achievable.
Channeling 2004 – Channeling 2006
@ “Channeling 2004”
Workshop on Charged and Neutral Particles
Channeling Phenomena
(Frascati 2-6 November 2004)
http://www.lnf.infn.it/conference/channeling
• Radiation of relativistic charged particles in periodic structures
• Coherent scattering of electrons and positrons in crystals
• Channeling radiation of electrons and positrons in crystals
• Channeling of X-rays and neutrons in capillary systems (micro- and nano-channeling)
• Novel types of sources for electromagnetic radiation (FEL, powerful X-ray sources)
• Applications of channeling phenomena (novel radiation sources, X-ray waveguides,
capillary/polycapillary optics)
@ “Channeling 2006”
International Conference on Charged and Neutral Particles
Channeling Phenomena
(LNF INFN, May - June 2006)
…with extended subjects for topics…
Collaboration & Acknowledgements
We have started collaboration with groups from:
Italy, Russia, USA, France, Germany, Switzerland,
Ukraine, Belarus, Armenia
…list will be extended…
Appendix
Additional material
The Scientific Case in the 10 nm  1 nm range:
High Peak Brightness ( > 1030 ) Ultra-short (< 100 fs) radiation pulses are of
great interest in various areas
• molecular physics (vibrational modes, bond breaking and formation at
l=10-1 nm)
•
physics of the clusters (phase transitions at l=10-1 nm,)
• surface and interfaces (real time dynamics and phase transitions, l=101 nm)
• time resolved chemical reactions (metastable and transition states,
magnetic scattering, confined systems, l=10-1 nm)
Free Electron Laser
Self-Amplified-Spontaneous-Emission
(No Mirrors - Tunability - Harmonics)
Collaborations
SASE FEL Electron Beam Requirements:
High Brightness B => High Peak Current & Low Emittance
l
MIN
r
 d
energy
spread
Lg 
2
1
K
2

 Bn K
minimum radiation wavelength
2
BBn 
undulator
parameter

3 2
K BBn n 1 K 2 2
gain length

R. Saldin et al. in Conceptual Design of a 500 GeV e+e- Linear Collider with
Integrated X-ray Laser Facility, DESY-1997-048
2I

2
n
The SPARX-ino opportunity
I = 1 kA
K=3
e = 0.1 %
n=4
lcr
[nm]
n=1
Energy [GeV]
I = 2.5 kA
K=3
e = 0.03 %
n=4
lcr
[nm]
n=1
Energy [GeV]
Potentials: Doyle-Turner approximation
Phys. Lett. A250 (1998) 360
NIM B143 (1998) 584
Potential for neutral particles: Moliere approximation
3
Z
 i r 
2
N e (r ) 


exp



i
i
4a 2 r i 1
 a 
C:
Z 6
a  0.05Z 1/ 3 
r nZ
N e (r )  curv 2a
a

screening
 i i
i
length

2
 i  
d
q
K

0
0
a


  r 2  rcurv2  2rrcurv cos q

1/ 2
Ne
“Continuous filtration”
Phys. Lett. A250 (1998) 360
NIM B143 (1998) 584
Nanocapillary: Bending efficiency
d
n  1  qc
p 

2
p2
 1 2

4 N e e 2
m
photon

plasma
rcurv
frequency
Effective bending:
frequency
rcurvq c
1
2d
2
m-capillary: 100-300 through 10-20cm
n-capillary:the reduce of the dimensions by several orders
with much higher efficiency
Nuovo Cimento B116 (2001) 361
Channeling Radiation
 0  10 eV
 0  2 2 max
forward  200 keV
Ex @22Elas (1-cos)
NX  T f
N e  N h
2
 coll
 2  10 9 / 11
• Produzioni di impulsi X :
109 fotoni/s, durata 3 ps, monocromatici
tunabili nel range 20 keV - 1 MeV.
Raggiungimento di 1011 fotoni/s con spot focali
all’interazione di 5 mm.
• Studi di tecniche di mammografia (e angiografia
coronarica) con X monocromatici.
• Studi di single molecule protein cristallography.
MaMBO Experiment:
Mammography Monochromatic Beam Outlook
La realizzazione di una immagine (su superficie 18x24 cm2) in tempi
di 2600 s scende a 2.6 s con l’upgrade previsto su SPARC che porta
il num. di fotoni a 2.5 1011 /s
The con strast (sens iti vit y to tis sue density variations ) goe s from 8% to 0.1%, whil e the
spatial r esolution go es from 0,15 -0,3 mm to 0.01-0.015 mm. This means the capabilit y to
detect a tumor 30 tim es smaller in volume, i.e. a 2 yea r earli er detection o f the tumor.
Accelerazione a plasma di pacchetti di elettroni (25 pC) da
100 MeV a 130 MeV con spread energetico < 5%, emitt.
< 1 mm, con laser non guidato (5 mm acc. length).
Accelerazione con laser guidato (5 cm) fino a 400 MeV,
gradienti > 5 GV/m.
n  
n p l p
n p 2
 p  50 mm
l p  30  100 mm