a. kanareykin euclid techlabs llc in collaboration with awa,anl
DESCRIPTION
ICFA Workshop on Novel Concepts for Linear Accelerators and Colliders. SLAC, July 7-10 2009. A. Kanareykin Euclid Techlabs LLC in collaboration with AWA,ANL. Dielectric Based HG Structures: Power Extraction, Tunability and Energy Transfer Efficiency. - PowerPoint PPT PresentationTRANSCRIPT
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
DIELECTRIC BASED HG STRUCTURES: POWER EXTRACTION, TUNABILITY AND
ENERGY TRANSFER EFFICIENCY
A. KanareykinEuclid Techlabs LLC in collaboration with AWA,ANL
ICFA Workshop on Novel Concepts for Linear Accelerators and
Colliders. SLAC, July 7-10 2009
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
ANL/Euclid Techlabs Collaboration on Dielectric Wakefield Acceleration
Euclid Techlabs: C.Jing, P.Schoessow, S.Antipov, F.Gao and A.Kanareykin
Argonne National Lab: M.Conde, J.G.Power, R.Conecny, Z.Yusof and W.Gai.
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Motivation/Outline
High Gradient DLA
26 GHz Wakefield Power Extractor
Tunable Dielectric Based Accelerator : Idea and Experiment
Ferroelectric Based Fast High Power Switching
Transformer Ratio X-Band Experiment, R>2 Demonstration
Energy Modulation
MW DLA issues: high gradient – drive beam, power extraction, tuning, efficiency, BBU, multipacting, …
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Drive Gun
Linac & Steering Coils Quads
Wakefield Structure
ExperimentalChambers 4.5 m
GVGV
YAG1 YAG2
Spectrometer
YAG5Dump/Faraday Cup
Slits
YAG4YAG3ICT1
ICT2 BPM
Single bunch operation– Q=1-150 nC– Energy=15 MeV– High Current = 10 kAmp
Bunch train operation64 bunches x 50 nC 50 ns long
Dielectric Based Accelerator
b a
Q
Cu
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Ne
~ 100 GeV Module
Ne
~ 1 GeV drive beam
~ 100 GeV Module
Major features: Short pulses (<20 ns), high gradient (200 ~ 300 MV/m)Drive beam structure directly
Many of the ~ 100 GeV Modules
~ 1 GeV drive beamPhotonsPhotons
Dielectric Based Linear Collider
Concepts
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
26GHz Dielectric-Based Power Extractor*
• A 26GHz power detector has been built and bench tested.
• A load has been built and bench tested.
• Beam test has been performed at AWA facility.
Parameters of 26GHz Dielectric Based RF Power Extractor
Geometric and accelerating parameters value
ID / OD of dielectric tube 7 mm /9.068 mm
Dielectric constant 6.64
Length of dielectric tubes 300 mm
R/Q 9788 /m
Drain time Td 3 ns
Steady power from AWA bunch train (20nC/bunch)
148 MW
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Beam Test of the 26GHz Power Extractor @ AWA Facility (May~June, 2009)
Load
Rf probe
LO=14.576GHz
11.424GHz BPF (228MHz
BW)
16GHz scope
Performed 3 experiments to date:
• Single beam--- to check the frequency
• 16-Bunch train--- to check the rf pulse formation
• 4-bunch train--- to achieve the high rf power
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Down-converted rf Trace of the 26GHz Power Extractor (4bunches)
11.44+14.576=26.016 GHz
Background noise direct to the scope
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Down-converted rf Trace of the 26GHz Power Extractor (16 bunches with 769ps separation)
11.44+14.576=26.016 GHz
4 bunches to reach the steady state
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Number is the percentage of charge transmission out of the structure.
Charge Sweeping
•Theoretically, 9nC29.6MW, 24.8MV/m if σz=1.5mm.
•Calibration will be taken after the experiment.
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Summary for 26GHz Dielectric Based Power Extractor
Successfully demonstrated the high frequency, high power rf source using dielectric-based scheme.
Experiment will be continued in the upgraded AWA facility next year.
Design of a fully featured power extractor( with transverse modes damping) is needed to prevent BBU in the high charge transportation.
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Tuning/Nonlinear Effects in Dielectric-Based
Accelerator
forsterite BST(M)
ε(E) for ferroelectric dielectric composite
Pulse steepening
high intensity wakefields in nonlinear structure
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Temperature tuning of 14 MHz/0K
Tunable DLATemperature Tuning*
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Tunable DLAFast DC Voltage Tuning
6 MHz at 20 kV/cm
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
0 1 2 3 4 5 6 7 8
E, V/um
K
95_1_1
95_1_2
95_3_1
95_3_2
95_5_1
95_5_2
95_8_1
95_8_2
95_2_1
95_2_2
95_4_1
95_4_2
95_6_1
95_6_2
95_7_1
95_7_2
epsilon(0)
0
50
100
150
200
250
300
1_1 1_2 3_1 3_2 5_1 5_2 8_1 8_2 2_1 2_2 4_1 4_2 6_1 6_2 7_1 7_2
серия 95
Е=5В/мкм
1
1.05
1.1
1.15
1.2
1.25
1.3
1.35
1.4
1.45
1.5
1 3 5 8 2 4 6 7
серия 95
K
KdcKpulse
New Ferroelectric
Lower dielectric constant, higher tuning range
ε< 300, k> 10% in air
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
BST(M) Ferroelectric Based L-band High Power Tuner
30 ns switching speed
Collaboration with Omega-P and FNAL
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Transformer Ratio
R < 2 under very general conditions: linear media; a relativistic, longitudinally symmetric drive bunch; and identical paths through the system of both drive and witness beams.
Transformer Ratio R = (Max. energy gain behind the bunch) / (Max. energy loss inside the bunch).
Distance behind the bunch, cm2520151050
Wakefield
, M
V/m 30
20
10
0
-10
-20
-30
W+
W- R= W+ /W-
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
(z)
z W -
W+
zd d
W -
W+
d
(z)
Reference: Bane et. al., IEEE Trans. Nucl. Sci. NS-32, 3524 (1985)
Reference: Schutt et. al., Nor Ambred, Armenia, (1989)
Some of the methods that can be employed to obtain R>2 include: a triangular drive bunch longitudinal profile; a train of Gaussian drive bunches of progressively increasing charge (ramped bunch train, RBT); the ring type driver, use of a proton drive beam so that the particles within the bunch can change positions during deceleration; and nonlinear plasma dynamics.
A single drive bunch was replaced by two bunches with charge ratio of 1:2:5 and a separation of 10.5 wavelengths of the fundamental mode
Ramped Bunch Train
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
LO (8.3GHz)
Signal from the field probe (13.6GHz) Signal to
the digital scope (5.3GHz)
LO (8.3GHz)
data (13.6GHz)
softwareDLA
6GHz digital scope
two-bunch wakefield experiment setup
Wakefields measurements
The field probe signal from the RBT in the 13.625 GHz DLA
Transformer Ratio Experiment
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Leading and Tailing 8 nC and 20 nC
bunches
satisfying the requirement of an equal decelerating field inside each bunch
the transformer ratio increases correspondingly, from R~ 1.8 to
R~ 3.
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Enhancement Factor of 1.31
Transformer Ratio R~2.3
An average measured transformer ratio enhancement by a factor of 1.31 over the single drive bunch case was obtained, R>2 has been demonstrated.
C.Jing, A.Kanareykin, J.G.Power et al. PRL 98, 144801, 2007
R>2 Experimentally Demonstrated.
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
4 bunch Transformer Ratio Experiments
time (ps)
Inte
nsi
ty (
arb
. uni
t.)
40 30 20 10 0 10 20 30 40
time (ps)
Inte
nsi
ty (
arb
. uni
t.)
40 30 20 10 0 10 20 30 40
time (ps)
Inte
nsi
ty (
arb
. uni
t.)
40 30 20 10 0 10 20 30 40
time (ps)
Inte
nsi
ty (
arb
. uni
t.)
40 30 20 10 0 10 20 30 40
zd d
W -
W+
d
(z)
laser pulse stacking method to stretch the AWA laser pulse from FWHM = 8 ps to 26.5 ps.
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Energy Modulated Bunch Train
Sequence of four bunches
z, cm1101009080706050403020100
Wak
efie
ld, M
V/m
550
500
450
400
350
300
250
200
150
100
50
0
-50
-100
-150
Sequence of four bunches
z, cm1101009080706050403020100
Wakefie
ld, M
V/m
140
120
100
80
60
40
20
0
-20
-40
-60
-80
-100
-120
-140
Ramped – 220 nC;Flat – 80 nCFor the same gradient:
A.Kanareykin et al, in preparation
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Sequence of four bunches
z, cm1101009080706050403020100
Wak
efie
ld, M
V/m
140
120
100
80
60
40
20
0
-20
-40
-60
-80
-100
-120
-140
Energy
Charge distribution is 20-20-20-20 nC, 1.5 mm length AWA bunch generated at the diamond based DLA structure with the inner radios of 1.5 mm, outer radius of 2.62 mm, ID=3 mm, OD= 5.24. Spacing between the bunches corresponds to 1.3 GHz or ~ 23 cm. Maximal accelerating gradient behind the train is 150 MV/m.
Energy Modulated Bunch Train.Energy Distribution
(10-30-50-70) MeV Train
A.Kanareykin et al, in preparation
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
Cons:- lower accelerating gradient- high charge for the last bunches- transverse fields increase- focusing for ramped bunch charges
Ramped Bunch Train
Pros:- laser beam manipulation for the train profile generation
Energy Modulated Bunch Train
Pros:- higher accelerating gradient- flat and low charge bunch train- last bunches have higher energy - transverse stability
Cons: - energy modulated driver bunch train generation - focusing of the energy profiled bunch train
Energy Modulation: pros and cons
A.Kanareykin et al, in preparation
ICFA Workshop on Novel
Concepts for Linear Accelerators and Colliders.
SLAC, July 7-10 2009
Euclid Techlabs LLC
SUMMARY
1. Successfully demonstrated the 26GHz, high power rf source using dielectric-based scheme.
2. Design of a fully featured power extractor ( with transverse modes damping) is needed to prevent BBU in the high charge transportation.
3. Tunable dielectric based accelerator concepts is presented
4. Transformer ratio experiment demonstrated R>2 for DWA
5. Energy modulated beam is considered, pros and cons are discussed.