SLAC FEL R&D Test Facilities Test Facility Task Force R. Hettel May 4, 2011

SLAC FEL R&D Test Facilities Test Facility Task Force

R. HettelMay 4, 2011

X-ray FEL Parameters – Now and Future(C. Pellegrini et al., summary of FEL workshops.)

† photons/s/mm2/mrad2/0.1% BW

red = parameter space to be developed

Parameter Now Future Photon energy (keV) Up to 10 Up to 100 Pulse repetition rate (Hz) ≤ 120 102-106 Pulse duration (fs) ~2-300 <1-1000 Coherence, transverse diffraction limited diffraction limited Coherence, longitudinal not transform limited transform limited Coherent photons/pulse 2x1012-3x1013 109-1014 Peak brightness (usual units†) 1033 1030-1034 Peak Power (W) 7x1010 > 1012 Average brightness (usual units†) 4x1022 1018-1027 Polarization linear variable, linear to circular Stability – intensity/energy RMS 3-15% < 3% Stability – time (fs) RMS 50 < 5

Stability – % mode size 10% < 10%

SLAC FEL R&D Test Facilities May 4, 2011

The Need for FEL Test Facilities

• Many facility-years of R&D required to expand and exploit the potential parameter space and performance capabilities of future X-ray FELs (and perhaps reduce their cost)

• Some R&D can be conducted at operational facilities like the LCLS, but availability highly limited and there is risk that R&D-related modifications may be a risk for user operations

• Accelerator test facilities, possibly more than one, are required to conduct the FEL R&D program. Facilities operating in parallel at different energies desirable, e.g.:

• low energy (order 5 MeV) for high brightness electron sources• mid-energy (order 100 MeV) ) for R&D on microbunching, CSR, injector

optimization, etc.• high energy (order GeV) for R&D on nm-seeding, high-E manipulation, etc.

• Nationwide R&D and test facility collaboration strategy preferred


• Identify and prioritize candidate programs for FEL accelerator R&D at SLAC that 1) are relevant to SLAC, and 2) relevant to national and international FEL programs (e.g. NGLS)

• Identify FEL test facilities at SLAC (existing and future) that can accommodate candidate R&D programs; estimate related implementation and operational costs and schedule for each

• Determine what other labs could host various R&D programs besides SLAC

• Recommend SLAC FEL test facility and R&D program options, including schedule of availability and implementation for each, as a function of assumed funding (e.g. 5 M$, 10 M$, 20 M$, 40 M$, etc.)

FEL R&D Test Facility Task Force - Charge


Future goal: develop collaborations and establish nation-wide accelerator test facility strategy

Task force members:C. Adolphsen A. Brachmann E. Colby P. Emma

J. Frisch A. Fry Z. Huang J. Galayda

R. Hettel C. Pellegrini T. Raubenheimer J. SchmergeJ. Seeman S. Tantawi J. Welch U. Wienands

B. WhiteTask force milestones:

Dec 2010: Facility overview, charter clarification, working group assignments, schedule

Jan-Mar 2011: Working group reports; task and schedule iteration

Mid-April: Draft recommendations for internal review

End April: Final report

FEL R&D Test Facility Task Force – Members and Schedule


Test Facility Scenario Definition Process

• FEL R&D list was prioritized, time of need and stakeholders identified

• R&D tasks were mapped onto all facilities at SLAC and rough costs of modifying each facility to host the experiment

• Optimal facilities were selected based on– cost of implementation– synergy between new and existing programs (both HEP and BES)– value as a long-term investment in SLAC infrastructure

• Four funding scenarios were defined ranging from modest growth above current funding to a profile that matched the full FEL R&D program.– Types of funding (LDRD, BES R&D, WFO, etc.) were also prescribed and

R&D tasks assigned by priority to the FEL program and appropriateness to the type of funding

• Illustrative year-by-year funding profiles were developed to understand the R&D synergies and interferences


SLAC FEL R&D Program, including NGLS (Z. Huang, J. Hastings et al.)



SLAC Test Facilities

Cathode Research Laboratory (CRL)• photocathode development

Gun/RF Test Facility (G/RFTF, presently ASTA)• high brightness electron source R&D diagnostics R&D

Next Linear Collider Test Accelerator (NLCTA) and ESB• low-E beam manipulation, compression and seeding (e.g. Echo-15)• electron source R&D • FEL technology test and measurement


Sector 10 Injector (LCLS-II injector, installed early) • new LCLS operating regimes • LCLS injector parameter optimization• code benchmarking • velocity bunching test

LCLS-I and –II• self-seeding (hard and soft) • ultrafast techniques• multiple bunches • polarization control • THz/X-rays

SLAC Test Facilities – cont.

LCLS-IIS10 Injector (early installation) soft x-ray

hard x-ray

LCLS-I


Facility for Advanced Accelerator Experiment Tests (FACET, user facility)• plasma wakefield acceleration is primary goal • THz source

development• beam diagnostics development

S0 Injector Test Facility - FUTURE• high energy laser seeding and beam manipulation (e.g. Echo-100, ESASE)• high energy bunch compression • advanced undulator testing • possible future FACET-II

SLAC Test Facilities – cont.

Sector 0 Injector Test Facility – Multi-GeV FEL R&D(J. Frisch et al.)

135 MeV:• Gun brightness optimization at 1pc – 3nC• Test other frequency RF guns (with new RF

sources: X-band high gradient, low frequency (NGLS), possibly DC gun)

• Multi-bunch tests. • Low charge diagnostics• Emittance exchange (with added

equipment)

250 MeV:• Compression Studies

• Velocity bunching• Nonlinear optics • Micro-bunching and COTR• CSR studies

• Laser Heater studies• Other Applications

• Compact /efficient THz source • Electron Diffraction source

2-10 GeV:• High-E bunch compression tests• Slotted spoiler tests• Diagnostics• Multi-bunch fast kickers• Short (~1GL) undulator tests• Seeding (NGLS) and ESASE• Future LCLS-III injector


Test Facilities at SLAC and ElsewhereLow energy, <25 MeV high brightness beam facilities:

LBNL – APEX SLAC – ASTA* SPRING - 8 Gun Test Lab UCLA – Pegasus

Medium energy, 25 MeV to 500 MeV beam facilities: BNL-ATF BNL-SDL DESY Zeuthen -PITZ INFN – SPARC LLNL / SLAC – Megaray PSI-FEL-Injector Shanghai-SDUV SLAC-

NCLTA SPring-8 - SCSS TA SLAC-Sector 10 Injector

High energy, > 500-MeV facilities:FNAL – NML KEK-ATF2 MIT Bates LINAC SLAC-ESTBSLAC –FACET SLAC Sector 0 ITF

High energy, >1 GeV FEL user machines (limited access time):DESY – FLASH SLAC - LCLS-I and -II Trieste - FERMI SPring-8 FEL

Other facilities, not well-suited for FEL R&D: ANL AWA CERN-CTF-III Cornell - CESR_TA Daresbury-ALICEDaresbury-EMMA Duke- Storage Ring FNAL - A0 / NICADD LBNL-BELLALLNL Pleiades SLAC - ESB TJNAF - JLab FEL TJNAF – CEBAFUCLA-Neptune


scenario facilities programs cost collab

1CRL, G/RFTF, NLCTA, LCLS,

laser lab

• gun/cathode development, ultrafast diagnostics, multibunch, THz, low-E bunch manip, self-seeding on LCLS

With LBNL/NGLS funds : • low-E seeding (NLCTA)• seeding laser development• NGLS diagnostics, timing/sync

4.5 M$/yr (LCLS Ops, BES R&D)

+~3M$/yr from NGLS (LBNL BES R&D/LDRD)

NGLS

2same as 1

+ early LCLS-II injector

• same as 1• 18-24 mos LCLS-II injector R&D

+ optimization• funds for polarization/taper

undulators on LCLS

~10 M$/yr(includes 3 M$ via NGLS)

NGLSother?

3 same as 2 + S0 ITF

• same as 2• Echo-100 demo• high-E bunch compression• advanced undulator testing• ESASE

~15 M$/yr + 40 M$ over 4 years for ITF/Echo-100 construction (32 M$ ITF construction + 3M$/yr via NGLS)

NGLSnational

FELFACET

4same as 3 + full R&D program

• same as 3• bunch compressors for Echo-

100• full FEL R&D program

~21 M$/yr + 40 M$ over 4 years for full ITF construction(~36 M$ ITF construction +3M$/yr via NGLS)

NGLSnational

FELFACET

Funding-Dependent Test Facility Scenarios


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Funding-Dependent Test Facility Scenarios – cont.

preliminary cost estimates are very approximate

• Future science applications, including those for LCLS and NGLS X-ray FELs, will require accelerators having cutting edge performance

• Investment in test facilities for accelerator R&D will be critical to the success of future FEL facilities in exploiting FEL performance potential

• Accelerator R&D can help reduce facility construction costs• Test facilities are invaluable for attracting high quality accelerator

scientists and students and for stimulating innovation in general • Important to have test facilities with different energy scales• Test facilities are expensive; even small facilities are expensive to

operate and maintain• Collaboration on FEL R&D with other laboratories (LBNL/NGLS, etc.)

will benefit all – NEXT STEP• Model for accelerator test facility support is changing but support is critical

for future R&D (HEP, BES, etc.) – need a national plan – NEXT STEP

FEL R&D Test Facilities at SLAC: Summary


Documents

SLAC FEL R&D Test Facilities Test Facility Task Force R. Hettel May 4, 2011