SEEDING EXPERIMENTS AT SEEDING EXPERIMENTS AT SPARCSPARC
Luca GiannessiLuca GiannessiENEAENEA C.R. FrascatiC.R. Frascati
On behalf of the SPARC collaborationOn behalf of the SPARC collaboration
International Conference on Charged and Neutral Particles Channeling Phenomena, 4-8 October 2010, Ferrara, Italy
L.G.L.G., , A. Petralia, G. Dattoli, F. Ciocci, M. Del Franco, M. A. Petralia, G. Dattoli, F. Ciocci, M. Del Franco, M. Quattromini, C. Ronsivalle, E. Sabia, I. Spassovsky, V. Quattromini, C. Ronsivalle, E. Sabia, I. Spassovsky, V.
Surrenti ENEA C.R. Frascati, IT. D. Filippetto, G. Di Surrenti ENEA C.R. Frascati, IT. D. Filippetto, G. Di Pirro, G. Gatti, M. Bellaveglia, R. Boni, D. Alesini, M. Pirro, G. Gatti, M. Bellaveglia, R. Boni, D. Alesini, M. Castellano, E. Chiadroni, L. Cultrera, M. Ferrario, L. Castellano, E. Chiadroni, L. Cultrera, M. Ferrario, L.
Ficcadenti, A. Gallo, A, Ghigo, E. Pace, B. Spataro, C. Ficcadenti, A. Gallo, A, Ghigo, E. Pace, B. Spataro, C. Vaccarezza, INFN-LNF, IT. A. Bacci, V. Petrillo, A.R. Vaccarezza, INFN-LNF, IT. A. Bacci, V. Petrillo, A.R. Rossi, L. Serafini INFN-MI, IT. M. Serluca, M. Moreno Rossi, L. Serafini INFN-MI, IT. M. Serluca, M. Moreno INFN-Roma I, IT. L. Poletto, F. Frassetto CNR-IFN, IT. INFN-Roma I, IT. L. Poletto, F. Frassetto CNR-IFN, IT. J.V. Rau, V. Rossi Albertini ISM-CNR, IT. A. Cianchi, J.V. Rau, V. Rossi Albertini ISM-CNR, IT. A. Cianchi,
UN-Roma II TV, IT. A. Mostacci, M Migliorati, L. UN-Roma II TV, IT. A. Mostacci, M Migliorati, L. Palumbo, Un. Roma La Sapienza, IT. G. Marcus, P. Palumbo, Un. Roma La Sapienza, IT. G. Marcus, P.
Musumeci, J. Rosenzweig, UCLA, CA, USA. S. Musumeci, J. Rosenzweig, UCLA, CA, USA. S. Spampinati, ST, IT and University of Nova Gorica, Spampinati, ST, IT and University of Nova Gorica, Nova Gorica, M. Labat, F. Briquez, M. E. Couprie, Nova Gorica, M. Labat, F. Briquez, M. E. Couprie,
SOLEIL, FR. B. Carré, M. Bougeard, D. Garzella CEA SOLEIL, FR. B. Carré, M. Bougeard, D. Garzella CEA Saclay, DSM/DRECAM, FR. G. Lambert LOA, FR. Saclay, DSM/DRECAM, FR. G. Lambert LOA, FR.
C.Vicario PSI, CH. C.Vicario PSI, CH.
Contributors
L. Giannessi, Channeling 2010
Seeded SPARC LayoutSeeded SPARC Layout
Ti:Sa Regenerative Amplifier
HHG generation Chamber
Periscope & injection chicane
In vacuumspectrometer 550-40nm
+ MUR
L. Giannessi, Channeling 2010
Infrared
L. Giannessi, Channeling 2010
Dec. 2007Dec. 2007
Infrared
GAS Cell
Differential vacuum
to Undulators
Focusing mirrors
Seeded OperationSeeded Operation
Seed FEL AmplifierFEL Amplifier
FEL Harmonic GenerationFEL Harmonic GenerationSeed 1
Modulator Radiator
2= 1/n, n=2
• Seed Sources:
– 400 nm in BBO crystal (high seed energy)
– 266 nm & 160 nm generated in gas
Cascaded FEL tested with both seed configurations
Seed FEL AmplifierFEL Amplifier
Seed FEL AmplifierFEL Amplifier
L. Giannessi, Channeling 2010
Seed @ 266 nm generated in Ar, ~50 nJ (±20nJ)6 UM 266 nm
Spectrometer slit @ 5 um - CCD saturated with nb filter @ 266nm, 17% T
Seed FEL AmplifierFEL Amplifier
Amplification ≈ 20x
L. Giannessi, Channeling 2010
Delay line ScanDelay line Scan
2 1 0 1 20
5 103
0.01
0.015
0.02
Linewidth (% - 1stdv)AverageMaxMin
Delay Line Displacement (mm)
Lin
ewid
th (
rms,
nm
)Adjustable delay
up to 4m
Delay line
4 2 0 2 40
0.5
1
0
10
20
30
40
50
Energy (uJ - 1 stdv)
Current (A)
Delay Line Displacement (mm)A
vera
ge E
nerg
y (u
J)
Cur
rent
(A
)
Cascaded FEL Cascaded FEL
FEL Harmonic GenerationFEL Harmonic GenerationSeed 1
Modulator Radiator
2= 1/n, n=2
• Seed @ 266 nm, 50 nJ 5-4-3 UM tuned @ 266 nm – 1-2-3 UM tuned @133 nm
3 3.5 4 4.5 50
0.5
1
1.5
2
(1 stdv)AverageMaxMin
Modulator UM #
Ene
rgy
(uJ)
L. Giannessi, Channeling 2010
L. Giannessi, Channeling 2010
FEL Harmonic GenerationFEL Harmonic GenerationSeed 1
Modulator Radiator
2= 1/n, n=2
0 500 1 103 1.5 10
3 2 103
0
10
20
30
40
Energy (nJ)
Pro
babi
lity
(%)
0 0.5 1 1.5 20
20
40
60
Rel. Linewidth (%)
Pro
babi
lity
(%)
FEL Harmonic GenerationFEL Harmonic GenerationSeed 1
Modulator Radiator
2= 1/n, n=2
0.6 0.8 1 1.2 1.40
10
20
30
40
50
Spot Size (rms mm)
Pro
babi
lity
(%
)
0 100 200 300 400 5000
5
10
15
20
25
Energy (nJ)
Pro
babi
lity
(%
)
0 1 2 30
10
20
30
Rel. Linewidth (%)
Pro
babi
lity
(%
)
0.5 1 1.5 20
10
20
30
40
50
Spot Size (rms mm)
Pro
babi
lity
(%
)
L. Giannessi, Channeling 2010
(2010/06/04)(2010/06/04) Seed @ 160nm Seed @ 160nm Seed intensity & SASE too low to be detected at the Seed intensity & SASE too low to be detected at the
spectrometer (< 1 nJ)spectrometer (< 1 nJ)
150 155 160 165 170
Wavelength (nm)
Inte
nsity
(a.
u.)
0 2 4 6 8 10 12 14 16 18 202 10
3
3 103
4 103
5 103
6 103
TotalSlit
Shot #
Ene
rgy
(uJ)
250 260 270 280 290
Wavelength (nm)
Inte
nsity
(a.
u.)
The seed @ 266 measured 1 day before shows the same double peak structure
Seeded FEL – 4 nJ
L. Giannessi, Channeling 2010
Effect of high intensity seedEffect of high intensity seed
GENESISSimulation
Seed Energy < 0.5 uJ
~ 0.7 uJ
~ 3 uJ
~ 9 uJ
Seeded FEL: field intensity above Seeded FEL: field intensity above saturationsaturation
Sim
ulat
ion
with
Per
seo
(w
ww
.pers
eo.e
nea.it)
L. Giannessi, Channeling 2010
Bunching coefficients in the front side of the pulseBunching coefficients in the front side of the pulse
Expected very efficient generation of high order harmonicsExpected very efficient generation of high order harmonics
L. Giannessi, Channeling 2010
Harmonics in a Superradiant Harmonics in a Superradiant pulsepulse Short bunching peaks on the pulse front side at the higher order Short bunching peaks on the pulse front side at the higher order
harmonicsharmonics Dynamics for non-linear harmonic evolution “faster” by the harmonic Dynamics for non-linear harmonic evolution “faster” by the harmonic
factor n. (i.e. Lfactor n. (i.e. Lg,ng,n ~ L ~ Lg g /n )/n ) Short bursts of harmonic radiationShort bursts of harmonic radiation Pulse structre preserved by the “solitary wave” behavior of this solutionPulse structre preserved by the “solitary wave” behavior of this solution
0 25 50 75 100-0.1
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Bun
chin
g C
oeff
icie
nts
Microbunch Coordinate (m)
1st harmonic 2nd harmonic 3rd harmonic 5th harmonic
0 25 50 75 1000.0
0.5
1.0
1.5
2.0
Microbunch Coordinate (m)
Peak
Pow
er (
GW
)
1st harmonic 3rd harmonic x 100
Harmonic emission suppressed by energy spread
Harmonic pulse
L. Giannessi, Channeling 2010
L. Giannessi, Channeling 2010
High harmonics down to 37 nmHigh harmonics down to 37 nm
Observation of 11° harmonic at 37nm
11h 10h 9h 8h 7h 6h 5h 4h 3h 2h 1h
Measured energy per pulse, spot size & and bandwidth of the first 11° harmonics
High intensity seed in a cascaded configurationHigh intensity seed in a cascaded configuration
Seed 1= 400nm
Modulator Radiator
2= 200 nm
0 3 6 9 12 15 18 21 24 27 300
5
10
15
20
0
50
100
150
200
TotalSlit
trace 4
Shot #
Ene
rgy
(uJ)
Energy jitter mainly due to e-beam energy jitter
L. Giannessi, Channeling 2010
CorrelationsCorrelationsLarge energy jitter –> large energy fluctuations
0.6 0.8 1 1.2 1.40
5 103
1 104
1.5 104
2 104
0
50
100
150
200
TotalSlit
Spot (rms mm)
Ene
rgy
(nJ)
Correlation Energy – Spot size
0.3 0.35 0.4 0.450
5 103
1 104
1.5 104
2 104
0
50
100
150
200
TotalSlit
Rel. Linewidth (%)
Ene
rgy
(nJ) Correlation Energy – Linewidth
199.3 199.4 199.5 199.6 199.7 199.80
5 103
1 104
1.5 104
2 104
0
50
100
150
200
TotalSlit
Mean Wavelength (nm)
Ene
rgy
(nJ) Redshift
Structure in the spectrum
Indication of saturation @200 nm
L. Giannessi, Channeling 2010
3h of the radiator3h of the radiator
66 nm
62 64 66 68 70 72
Wavelength (nm)
Inte
nsity
(a.
u.)
0 3 6 9 12 15 18 21 24 27 300
0.05
0.1
0.15
0.2
TotalSlit
Shot #
Ene
rgy
(uJ)
L. Giannessi, Channeling 2010
Conclusions Conclusions (From Channeling 2006)(From Channeling 2006)
SPARC represents a unique opportunity for studying single pass FEL and SPARC represents a unique opportunity for studying single pass FEL and FEL cascades in seeded modeFEL cascades in seeded mode
Conventional lasers and FEL are merged in a single deviceConventional lasers and FEL are merged in a single device
New experiments are foreseen in the next future New experiments are foreseen in the next future The harmonic cascade The harmonic cascade Multistage cascade and the Fresh Bunch injection techniqueMultistage cascade and the Fresh Bunch injection technique Superradance in a cascade and Superradance in a cascade and the harmonic cascadethe harmonic cascade FEL amplification from a gas HHG source/harmonic generationFEL amplification from a gas HHG source/harmonic generation
These new schemes extend the foreseen SPARC spectral range to 44nm - These new schemes extend the foreseen SPARC spectral range to 44nm - 500 nm500 nm
The experience resulting from those experiments will provide the confidence to The experience resulting from those experiments will provide the confidence to extend the seeded FEL cascade wavelength operation range in higher extend the seeded FEL cascade wavelength operation range in higher beam energy devices as beam energy devices as SPARXSPARX
ok
ok
In progress
true
37 nm