FACET-II Science Workshop 2019

Date: October 29 - November 1, 2019
Location: Building 40 Sycamore Conference Room, SLAC

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 wake field 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 photo-injector 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.

Registration (closed)


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.

To listen in via zoom meeting: https://stanford.zoom.us/j/514840095

Start TimePresentationPresenterAffiliation
09:00 amFacility status (run schedule for 2020)Vitaly YakimenkoSLAC
09:30 amExperimental science goals, 
beam requirements, detection/hardware needs
Mark HoganSLAC
10:00 amBeam configurations for different experimentsGlen WhiteSLAC
10:30 amCoffee Break  
11:00 amCommissioning status & beam 
parameters for 2020
Jerry YockySLAC
11:30 amMachine learning experimentsClaudio EmmaSLAC
12:00 pmLinac DiagnosticsNate LipkowitzSLAC
12:30 pmLunch  
01:30 pmExperimental areaMark HoganSLAC
01:50 pmParticle and Gamma Diagnostics
 at the Dump table
Doug StoreySLAC
02:10 pmLaser status & possible future upgradesBrendan O’SheaSLAC
02:40 pmCoffee Break  
03:10 pmFuture upgrades:  
03:10 pmStart to End Simulations of 
Electrons: baseline and upgrades
Glen WhiteSLAC
03:40 pmPositrons and Sailboat/UFOGlen WhiteSLAC
04:00 pmE-300: Two-bunch pump 
depletion and emittance preservation
Chan JoshiUCLA
05:00 pmDiscussion  
05:30 pmAdjourn  
06:00 pmReception @ The Dutch Goose  

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.

To listen in via zoom meeting: https://stanford.zoom.us/j/514840095

Start TimePresentationPresenterAffiliation
09:30 amE-320: Probing Strong-field QED 
Sebastian MeurenSLAC/Stanford
10:30 amCoffee Break  
11:00 amE-301: Tailored Plasma Sources for 
Emittance Preservation in PWFA 
and High-Brightness Plasma-
Injected Beams
Mike LitosCU Boulder
12:00 pmE-324: Optical visualization of
 beam-driven plasma wakefield
Michael DownerUT Austin
12:30 pmLunch  
01:30 pmE-303: Generation and Acceleration
 of Positrons at FACET-II
Ken MarshUCLA
02:00 pmE-305: Beam filamentation and 
bright gamma-ray bursts
Sebastien CordeEcole Polytechnique
03:00 pmCoffee Break  
03:30 pmE-310: Trojan Horse-IIBernhard HiddingUniversity of Strathclyde
04:30 pmExperimental Safety 
Review Status
Christine ClarkeSLAC
05:00 pmAdjourn  

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.

To listen in via zoom meeting: https://stanford.zoom.us/j/514840095

Start TimePresentationPresenterAffiliation
09:00 amSummary of FNAL Crystal Workshop
 & Opportunities @ FACET-II
Vladimir ShiltsevFNAL
09:30 amRoadmap towards linear 
colliders based on plasma 
Mark HoganSLAC
09:45 amNew directions in positron
 acceleration research
Spencer GessnerSLAC
10:30 amCoffee Break  
11:00 amTransversely tailored plasmasSeverin DiederichsLBNL/DESY
11:30 amTransversely tailored plasmasShiyu ZhouUCLA
12:00 pmLunch  
01:20 pmAttosecond scienceAgostino MarinelliSLAC
01:50 pmPositron production and 
capture from a foil
Hiroki FujiiUCLA
02:10 pmQuasi-hollow channels +
 other IST ideas
Thales SilvaIST
02:50 pmCoffee Break  
03:20 pmNeutral beam filiamentationFrederico FiuzaSLAC
03:50 pmExperimental progress in
 LWFA to PWFA staging
Sebastien CordeEcole Polytechnique
04:20 pmMachine/physics studies 
towards FACET-III stability
Claudio EmmaSLAC
04:50 pmDiscussion towards new directions  
05:30 pmAdjourn  

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.

To listen in via zoom meeting: https://stanford.zoom.us/j/514840095

Start TimePresentationPresenterAffiliation
09:00 amUser needs - an LCLS perspectiveAgostino MarinelliSLAC
09:30 amOpportunities & Challenges of 
Using High-brightness Beams 
from PWFA Injectors
Mark HoganSLAC
10:00 amProgress towards seeded LWFA-
based FEL and lessons learned
Sebastien CordeEcole Polytechnique
10:30 amCoffee Break  
11:00 amThe LUX FacilityAndreas MaierUniversity of Hamburg/DESY
11:30 amA Compact Laser‐Plasma‐ 
Accelerator‐Based FEL for 
Ultra‐Fast Hyper‐Spectral Experiments
Jeroen van TilborgLBNL
12:00 pmOptimization of parameters 
12:30 pmLunch  
01:30 pmNeXource and the STFC PWFA-
FEL program
Bernhard HiddingUniversity of Strathclyde
02:00 pmX-FELs driven by GeV and 10s of 
GeV electrons from density downramp
Xinlu XuSLAC
02:30 pmDiscussion of challenges: stability, 
pointing, matching…
03:00 pmAdjourn  
AdliErikUniversity of Oslo
BerbouchaMeriameSLAC National
Accelerator Laboratory
BrooksJasonThe University of 
Texas at Austin
BucksbaumPhilipPULSE, Stanford 
and SLAC
CordeSebastienEcole Polytechnique
University of Hamburg
DownerMikeUniversity of 
Texas at Austin
FujiiHirokiUCLA EE
HiddingBernhardUniversity of 
Strathclyde & 
Cockcroft Institute
KononenkoOlenaEcole Polytechnique
LitosMichaelUniversity of 
Colorado Boulder
MaierAndreasUniversity of
MarshKennethUCLA EE
NghiemPhu Anh PhiCEA-IRFU
PaganoIsabellaUniversity of 
Texas at Austin
San Miguel ClaveriaPabloSLAC/Ecole
ScheinkerAlexanderLos Alamos
 National Laboratory
ShiltsevVladimirFermi National 
Accelerator Laboratory
SilvaThalesInstituto Superior
StoreyDougSLAC National
 Accelerator Laboratory
of Strathclyde
van TilborgJeroenLBNL
WienandsH.-Ulrich (Uli)Argonne National 
YADAVMONIKASplit site PhD at 
University of Liverpool/UCLA
ZgadzajRafalUniversity of
 Texas at Austin
ZhouShiyuTsinghua University