1. SLAC ARD Test Facilities
Tor Raubenheimer
February 9th, 2012

2. Test Facilities at SLAC
Accelerator Research requires R&D facilities
Development has a long timeline
Important to have facilities with different energy scales
Need to match problems to scale of facilities
High energy facilities for unique problems
Low energy facilities more flexible and faster turn-around
ASTA/CTF; NLCTA; FACET/ESTB; ITF/FACET-II
Test facilities are expensive
Even small facilities are expensive to operate and maintain
University participants require more of a user facility paradigm
Model for facility support is changing but is critical for future R&D
Need plan for development and funding of Test Facilities

3. Example: NLCTA beam physics R&D
Thz - Tunable, narrow band THz generation
AO - All-optical mapping of the e-beam longitudinal ph. sp.
OL - Linearization of the microbunching phase space with 2+ laser harmonics
SC amplifier – Study microbunching and space-chare
OAM-FEL - Efficient up-conversion of transverse mode in FEL to generate light modes with associated orbital angular momentum.
Echo-75 – use EEHG technique to generate 75th harmonic
Technology demonstrations: cryo-undulator, rf undulator, …

4. Need a Plan Very high level plan was developed which focused on ITF
ASTA and NLCTA have not been part of the future plans of the laboratory
Not clear that omission is entirely intentional
Good to have ambitious plans but very unclear messages to DOE and lab personnel
May be important to make choices but important to be realistic about funding and timescales
Many opportunities for future evolution: ASTA  CTF; NLCTA  ICS, UED or beam physics user facility
Loss of capability is largely not recoverable
I believe the breadth of test facilities has been critical for ARD and will continue to be so

5. High Brightness Injector Program Three Parallel Experimental Efforts
Cathode Test Facility
ASTA Facility Photocathode R&D aimed at understanding LCLS lifetime and damage issues
Test rf gun modifications before installation in LCLS-I or II
LCLS-II Injector Incremental upgrade of LCLS-I with opportunity for R&D during commissioning
Injector R&D Program
NLCTA Facility Simulation and experimental program aimed at significant improvement in brightness
Longer term R&D aimed at high brightness cathodes
with lower thermal e
(coatings, smoothness, new materials)
Construction in ~2014 and commissioning in ~2015 to study injector physics before LCLS-II operation
Design studies on rf gun design, CSR micro- bunching and cathodes
Rf gun development and testing at NLCTA in 2012
NLCTA R&D on injector beam physics
Combined HB program requires ~3M/yr new funding