Transcript Photo Injectors for TTF-FEL

Future plans at PITZ:
PITZ 2
Anne Oppelt
DESY Zeuthen
TTF2 review meeting
Salzau, 20.1.2003
Outline
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Brief introduction
Motivation for PITZ 2
Layout of the facility
Planned physics studies
Further studies
Collaboration partners
Summary
Main goal of PITZ
test and optimize high brightness electron sources
for Free Electron Lasers and Linear Colliders
intense electron beams with
small transverse and
longitudinal emittance
use most advanced techniques
Emittance at PITZ1
emittance
beam size
Simulation of Ph.Piot
strong emittance growth
EMSY
PITZ 2
large extension of the facility
and its research program
with two main goals:
study the emittance
conservation principle
extensive R&D
on photo injectors
Principle of emittance conservation
Goal: produce and conserve low emittance beams
use a booster cavity to achieve higher beam energy,
where space charge effects are reduced (∝1/γ2 )
and apply invariant envelope technique to conserve
the minimum emittance
Simulation of the booster cavity (Ph.Piot)
matching
condition
(M.Ferrario)
diagnostic section
Planning
upgrade facility with a normal conducting booster
cavity in 2 steps:
2004: increase the beam energy to 16 MeV using
a copper model for the TESLA cavity
2005: use a new developed CDS-structure based
on the TESLA e+- preaccelerator design to
increase the beam energy up to 40 MeV
CDS booster cavity
Design by INR Troitsk
based on PPA for TESLA
Preliminary layout of PITZ 2
transverse
emittance
Gun Booster
masks
quads
longitudinal
phase space
and BPMs, screens,
streak camera, …
Extensive R&D on optimized
electron sources for FEL operation:
– development, optimization, and characterization
of new gun cavities, e.g. high duty cycle gun for
high repetition rate FELs and ERLs, or rf-gun
with improved gun geometry
– studies of photo cathodes
– comparison of detailed experimental results with
simulations and development of simulation tools
Further subjects are:
– remote control of PITZ (GAN)
– conceptional work for the production of flat
and polarized electron beams for TESLA
– studies of bunch compression methods,
coherent synchrotron radiation (CSR), …
Laser system development by MBI
– flat top temporal shape (20 ps FWHM)
– short rise and fall times (≤ 2 ps)
– homogenous transverse intensity profile
– laser parameters widely variable
532 nm
4 ps
first promising
results, but rise
time, flat top,
laser stability have
to be improved
Collaborating institutes
Beside the existing partners of DESY, namely
BESSY Berlin, MBI Berlin, TU Darmstadt,
INFN Milan, INRNE Sofia, INR Troitsk,
and YERPHI Yerevan,
new partners are very welcome !!!
Summary
• large extension of existing facility
• study emittance conservation with booster and
new beamline
• develop stable and reliable laser system with
flat top temporal and transverse radial laser
beam profile
• improve simulation tools for extensive beam
dynamics studies
• develop and test a high duty cycle gun cavity
and do further studies on photocathodes