aerial photo of the linear accelerator

FACET-II Science Workshop 2019

Name:

FACET-II Science Workshop 2019

Date:

October 29th - November 1st, 2019

Location:

SLAC National Accelerator Laboratory, Building 40 Sycamore Conference Room

Overview:

FACET-II is a new National User Facility at SLAC National Accelerator Laboratory scheduled to begin operating in 2020. A photoinjector in a configuration similar to that of LCLS will enable FACET-II to investigate acceleration and beam quality preservation utilizing beams with an emittance two-orders of magnitude lower than what was routinely available at FACET. The resulting improvement in beam density will enable FACET-II to study new effects like the motion of plasma ions and unintended beam ionization in the plasma sources. Additional plasma-based experiments have been proposed for generating bunches with orders of magnitude lower emittance that will ultimately be needed for both an early application of a PWFA and for a plasma-based future linear collider. Phased upgrades to FACET-II are expected to provide high-intensity positron bunches, a capability unique in the world, to experimentally investigate the optimal technique for high-gradient positron acceleration in plasma.The high-intensity beams open the door to an even broader experimental program including dielectric wakefield acceleration (DWA), Strong Field QED and bright gamma bursts from plasma instabilities.

A baseline design for FACET-II has been established that progressively increases capabilities in three distinct stages and is captured in the FACET-II CDR and TDR​. Stage one completes a new photoinjector at Sector 10 and re-establishes operations with high-energy high-brightness electron beams. Stage two will add a new positron damping ring system and allow user runs with high-current positron beams. Stage three will upgrade the chicane in sector 20 for simultaneous delivery of positrons and electrons to the experimental area.

The FACET-II team is organizing the fourth in a series of workshops to (1) Communicate the facility status, capabilities and upgrade plans, (2) Review experimental installation readiness and run plans for 2019/2020, (3) Develop the science case for positrons and other upgrades and (4) Assess the opportunities and challenges of plasma driven FELs.

 

Facility Status, capabilities and upgrade plans: On the first day we will present and discuss what we expect to be available upon construction of FACET-II as well as capabilities enabled by future upgrades.

Experimental installation readiness & run plans for 2019/2020: On the second day we would like experiments to present a description of an engineering solution for how the experiment will be installed, a plan for execution and a description of the observables. Presentations should conclude with a clear definition of success for the first phase of the experiment.

Developing the science case for positrons and other upgrades: On the third day, the first goal is to clarify the science case for positrons. The second goal is to discuss ideas for new experiments and to understand the match to FACET-II capabilities. We hope through discussions to see an evolution of the experimental needs that improve chances for a positive review of potential proposals at the next Program Advisory Committee Meeting.

PresentationPresenterAffiliation
Summary of FNAL Crystal Workshop & Opportunities @ FACET-IIVladimir ShiltsevFNAL
Roadmap towards linear colliders based on plasma acceleratorsMark HoganSLAC
New directions in positron acceleration researchSpencer GessnerSLAC
Transversely tailored plasmasSeverin DiederichsLBNL/DESY
Transversely tailored plasmasShiyu ZhouUCLA
Attosecond scienceAgostino MarinelliSLAC
Positron production and capture from a foilHiroki FujiiUCLA
Quasi-hollow channels + other IST ideasThales SilvaIST
Neutral beam filiamentationFrederico FiuzaSLAC
Experimental progress in LWFA to PWFA stagingSebastien CordeEcole Polytechnique
Machine/physics studies towards FACET-III stabilityClaudio EmmaSLAC

Assessment of plasma driven FELs: Plasma accelerators, both PWFA and LWFA, are being investigated as enabling technologies for 5th generation light sources. The large accelerating fields afford compact GeV beams and are predicted to produce beams with unprecedented brightness. On the fourth day we hope to discuss both the promise of this new technology as well as the practical challenges that must be addressed. 

Plasma accelerators are already producing beams approaching the quality needed for FELs. This session will discuss the practical challenges of transitioning these beams to User experiments and FELs. We will seek to define common challenges that need to be addressed and what details need to be reported to allow members of the FEL community to judge ore progress.

PresentationPresenterAffiliation
User needs - an LCLS perspectiveAgostino MarinelliSLAC
Opportunities & Challenges of Using High-brightness Beams from PWFA InjectorsMark HoganSLAC
Progress towards seeded LWFA-based FEL and lessons learnedSebastien CordeEcole Polytechnique
Coffee Break  
The LUX FacilityAndreas MaierUniversity of Hamburg/DESY
A Compact Laser‐Plasma‐ Accelerator‐Based FEL for Ultra‐Fast Hyper‐Spectral ExperimentsJeroen van TilborgLBNL
Optimization of parameters for EuPRAXIAPhu Anh Phi NGHIEMCEA-IRFU
Lunch  
NeXource and the STFC PWFA-FEL programBernhard HiddingUniversity of Strathclyde
X-FELs driven by GeV and 10s of GeV electrons from density downramp injectionXinlu XuSLAC
Discussion of challenges: stability, pointing, matching…All 
workshop participants seated eating dinner at local dive the Dutch Goose
Workshop participants enjoying the tight seating and cold beer at the Dutch Goose