1. Ideas for medium and long term facility upgrade Roberto Corsini for the CLIC Accelerator Collaboration

2. Short term upgrade Present
Future: CALIFES minimum upgrade configuration
RF deflector
Test Area
Spectrometer
Add an available S-band klystron + modulator (N.B.: present one goes to AWAKE!)
More RF power (beam energy), more operational flexibility (power in 1st structure, phase in structures 2 and 3), shorter bunches, possibility of running without RF pulse compression
Option: use another S-band klystron + modulator to power existing RF deflector (bunch length measurements)
Reconfigure present TBM area as test area
Most (all) hardware already existing

3. Present CALIFES RF network
Building 2010
CLEX

4. RF Upgrade KLYSTRONS AND MODULATORS 1st FLOOR
G. McMonagle
Building 2001
Building
2010
Implementation of Klystrons and Modulators in CTF3
Building
2013
MKS 30
Implementation of Klystrons and Modulators in CTF3
KLYSTRONS AND MODULATORS 1st FLOOR
BUILDINGS 2001, 2013 and 2010

5. RF upgrade – present status
MKS 30
Existing CALIFES set up
5 Hz repetition rate
MKS30 will be transferred to AWAKE
G. McMonagle

6. RF Upgrade – constraints & options
Some modulators will not be supported by TE-EPC and BE-CO next year
What can be reused for CALIFES to give more flexible performance and higher energy if necessary?
1st step: use compatible modulators in existing position, no upgrade for rep rate
2nd optional step: rep rate upgrade, optimize position
Other considerations to be taken into account
Main water cooling station must be kept operational
Two water temperature stabilization stations to be kept operational
Pulse compressor temperature control station to be operational
Low Level RF and high power RF (klystrons) spares available from the other CTF3 modulators
G. McMonagle

7. RF upgrade – proposal
G. McMonagle

8. RF upgrade – proposal
G. McMonagle

9. By using suggested modulators
No support from TE-EPC needed for high power RF
Removes incompatibility with future controls interface
Using MKS31
all in place just waveguide configuration to change
Most waveguides are available somewhere in the CTF3 facility
Using MKS07
Modification of waveguide configuration
Movement of charging supplies, PLC etc. from MKS 11, cabling costs manpower
Keeps all CALIFES modulators in buildings 2010 and building 2013
Using MKS11 (instead of 07)
Just waveguide modifications
But modulator situated in building 2001
Using MKS30 area
Transfer solid state modulator 21 from building 2001 to building 2010, allows 50Hz rep rate for structure testing.
Waveguide modifications
G. McMonagle

10. Other upgrades (or consolidation issues)
Driven by:
Experimental needs (assessment to be done after workshop – need information!)
Practical considerations (reliability and availability, ease of maintenance, running cost…)
Driven by experimental requirements I, beam parameter improvements:
Shorter bunches
Higher charge per bunch
Higher total charge / longer trains
Smaller emittance
Higher rep rate
Higher beam energy
Driven by experimental requirements II, operational
Pump and probe capability (independent tuning of time/position of two or more bunches)
X-band RF power
Available space for experiments
Multiple beam lines
Timing, synchronization, others

11. Beam parameters, wish list
Bunch length 100 fs range most users Charge per bunch up to 5 nC THz, beam loading Train length 200 ns range beam loading Emittance < 1um plasma Energy up to 500 MeV Synchrotron rad down to 5-10 MeV VESPER Rep rate 25 Hz X-band Double bunch impedance, plasma Pulse shaping plasma, X-FEL … to be completed

12. CALIFES laser issues
Issues: long (70 m) optical transfer line (pointing instability, power losses, aberrations)
Photoinjector laser lab (1st floor) and optical transfer line to PHIN and CALIFES
Front End
Harmonic-
generation
Amplifier
CALIFES
PHIN
Issues: quite complex no turn-key system, not optimized to CALIFES (new) needs.
Maintenance/spares to be checked.

13. CALIFES laser Today’s CALIFES setup
Pulse-picker with step size >1 bunch
Today’s CALIFES setup

14. CALIFES laser, issues and upgrades
Laser pulse shape
Pointing instability
Curtesy of W. Farabolini
Curtesy of W. Farabolini
Consider to:
Move laser lab closer to CALIFES gun
Simplify/consolidate present system
Change laser to new one (commercial?)
Others…
Need input on parameters
(pulse length, rep rate, stability, pulse shaping)

15. Laser upgrades
Many applications need/would prefer improved laser parameters, e.g.:
Shorter pulses (< 1 ps)
Bunch comb (16 bunches…)
Pulse shaping
Higher power/pulse
Consider also the possibility of double pulse with tunable distance
Some proposed applications would need a different dedicated laser system
Other don’t strictly need it, but may profit
Need to understand parameters range, cost, infrastructure, manpower and maintenance needs, as well as potential synergies

16. X band capability - BOX1 connection
Availability of X-band high power RF is an asset for CALIFES
XBOX1 obvious choice
Actually feed CTF2 test area and/or Dogleg beam loading experiment
Low-loss RF line may be readapted and moved
Alternative: move XBOX1 on top of desired location
XBOX1
Low-loss RF transfer
Drive beam, 1-3A, MeV
 50 mm circular waveguide
CTF2 test area
Dogleg experiment

17. Space availability
The present CALIFES beam line is quite crowded. Even completely dismantling the Two-Beam Module, only a few meters will be available for equipment
May sacrifice matching sections, instrumentation, spectrometers, but…
Need to understand space requirements, typical times for installation and turnaround, compatibility, synergies
Option: second beam line

18. Space availability

19. Options for a second beam line
In CLEX there’s plenty of (transverse) space for a 2nd beam line (and possibly a 3rd one as well)
Plenty of hardware to recuperate
Dogleg can be used for compression
Longitudinal space still limited
May consider to extend towards CTF2

20. New source/gun
Pump and probe experiments (Plasma, THz, impedance) would profit from a second independent electron source.
A new source can also be optimized for short bunches and low emittance, beyond reach of the present CALIFES gun.
A new source would not only be a tool, but an R&D goal in itself
Some attractive possibilities: X-band photoinjector, plasma-based source
Possible synergy with AWAKE (100 fs, ~ 400 A peak current, 50 MeV)
See Steffen’s talk

21. Options for a second beam line + source
2nd line (alternative)
New source
Test area
CALIFES
2nd line
CLEX