FACET: A Facility for Advanced FACET: A Facility for Advanced - - PowerPoint PPT Presentation

▶
facet a facility for advanced facet a facility for
SMART_READER_LITE
LIVE PREVIEW

FACET: A Facility for Advanced FACET: A Facility for Advanced - - PowerPoint PPT Presentation

Nov 15, 2023 29 likes •423 views

FACET: A Facility for Advanced FACET: A Facility for Advanced Accelerator Research at SLAC Accelerator Research at SLAC U. Wienands, SLAC U. Wienands, SLAC presently at CERN on a LARP-sponsored presently at CERN on a LARP-sponsored Long Term

slide-1
SLIDE 1
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 1

FACET: A Facility for Advanced FACET: A Facility for Advanced Accelerator Research at SLAC Accelerator Research at SLAC

  • U. Wienands, SLAC
  • U. Wienands, SLAC

presently at CERN on a LARP-sponsored presently at CERN on a LARP-sponsored Long Term Visit Long Term Visit Division Head for FACET Linac Division Head for FACET Linac

I am indebted to Mark Hogan for providing material on plasma acceleration I am indebted to Mark Hogan for providing material on plasma acceleration

slide-2
SLIDE 2
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 2

Outline Outline

  • Motivation

Motivation

  • The FACET Project

The FACET Project

  • The Experimental Program

The Experimental Program

  • Conclusion

Conclusion

slide-3
SLIDE 3
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 3

Accelerator Evolution Accelerator Evolution

  • Primary tools to advance HEP

Primary tools to advance HEP

  • Reaching limits of support

Reaching limits of support

– size, costs, time scales – Internationalization can buy time, but only a little

  • Advance can come from

Advance can come from fundamental research into new fundamental research into new accelerating mechanisms accelerating mechanisms

– Different materials – Higher frequencies – …

slide-4
SLIDE 4
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 4

High Gradient Acceleration High Gradient Acceleration

  • The fundamental parameter is the accelerating

The fundamental parameter is the accelerating gradient gradient

– reduce size, thus costs, of new facilities – may help in increasing beam brightness as well

  • Candidate technologies for high gradients:

Candidate technologies for high gradients:

– High-frequency metallic structures (=> CLIC) – Dielectric structures (beam or laser driven) – Plasma wakefields

  • FACET aims at plasma and dielectric acceleration

FACET aims at plasma and dielectric acceleration

O(100) MV/m O(1) GV/m O(10) GV/m

slide-5
SLIDE 5
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 5

World-wide interest in Plasma- World-wide interest in Plasma- Wakefield Acceleration Wakefield Acceleration

  • T. Katsouleas
slide-6
SLIDE 6
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 6

Overall Thrust of FACET Overall Thrust of FACET

  • The primary goal of FACET is proof in principle

The primary goal of FACET is proof in principle that plasma acceleration can accelerate a bunch that plasma acceleration can accelerate a bunch

– characterize the mechanism under beam loading – estimate beam parameters (witness) – estimate the efficiency and gradient reachable in practice – demonstrate acceleration of a positron bunch

  • Beyond that, FACET will provide a facility to

Beyond that, FACET will provide a facility to explore other accelerator physics issues explore other accelerator physics issues

– Wakefield measurements (ILC, CLIC) – Matter in extreme fields – new radiation sources using crystals

slide-7
SLIDE 7
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 7

The FACET Facility The FACET Facility

  • Driven by first 2/3

Driven by first 2/3rd

rd of the SLAC 2-mile linac

  • f the SLAC 2-mile linac

– new exp. area in Sec. 19-20. – new compressor chicane in Sec. 10 for e+ – new compressor chicanes in Sec. 19. – e– and slightly later also e+

slide-8
SLIDE 8
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 8

Energy Energy 23 GeV 23 GeV Charge Charge 3 nC 3 nC Sigma z Sigma z 14 µm 14 µm Sigma r Sigma r 10 µm 10 µm Peak Current Peak Current 22 kAmps 22 kAmps Species Species

e e-

  • & e

& e+

+

The FACET Facility The FACET Facility

  • Beam Parameters:

Beam Parameters:

– many of these can be tuned to match requirements – 30 Hz repetition rate

slide-9
SLIDE 9
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 9

Staged Bunch Compression Staged Bunch Compression

slide-10
SLIDE 10
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 10

S10 Compressor Chicane S10 Compressor Chicane

slide-11
SLIDE 11
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 11

“ “Sailboat Sailboat” ” Chicane (S20) Chicane (S20)

  • 3rd-stage bunch compression

3rd-stage bunch compression

  • precision timing

precision timing e e+

+ and

and e e–

– bunches wrt. each other

bunches wrt. each other

– allow e+ bunch to sample wake from e– bunch

slide-12
SLIDE 12
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 12

slide-13
SLIDE 13
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 13

slide-14
SLIDE 14
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 14

Linac Removed from FACET Expt. Area Linac Removed from FACET Expt. Area

slide-15
SLIDE 15
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 15

Some of the Beam Diagnostics Some of the Beam Diagnostics

FACET IP

SLAC linac: BPM’s, Toroids, Feedbacks, GADCs, triggers

slide-16
SLIDE 16
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 16

FACET Status FACET Status

  • C

Construction

  • nstruction expected to finish in Spring 2011

expected to finish in Spring 2011

– accelerator and beam commissioning soon after.

  • Experimental

Experimental program program to to begin begin Summer Summer 2011 2011

  • First Users Workshop @ SLAC March 18-19, 2010

First Users Workshop @ SLAC March 18-19, 2010

– http://www-conf.slac.stanford.edu/facetusers/spring2010/ – 40 people, 9 institutions

  • Argonne, Brookhaven, Euclid Techlabs, Fermilab, SLAC,

Stanford, UCLA, USC, UT Austin

– 4 Working groups considered ideas for first experiments:

  • Plasma Wakefield Acceleration
  • Dielectric Wakefield Acceleration
  • Materials in Extreme Conditions
  • Crystals & Novel Sources of Radiation
  • Beamtime allocated in

Beamtime allocated in a a proposal driven proposal driven process process

slide-17
SLIDE 17
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 17

Checking out the Linac Checking out the Linac… …

slide-18
SLIDE 18
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 18

PWFA: Particle to Beam PWFA: Particle to Beam Acceleration Acceleration

Witness Bunch Drive Bunch

x ∝ ΔE/E ∝ t

Disperse the beam in energy Adjust final compression ...selectively collimate

x [mm] dp/p [%]

dp/p [%] z [mm]

80cm Plasma

  • Collimation system to craft drive/witness bunch from single

Collimation system to craft drive/witness bunch from single bunch (similar to BNL ATF wire system) bunch (similar to BNL ATF wire system)

 Vary charge ratio, bunch lengths, spacing by changing collimators and linac phase, R56  Study wake loading in the non-linear regime for the first time

slide-19
SLIDE 19
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 19

Beam Loading & Wake Evolution Beam Loading & Wake Evolution

QuickPIC simulation, D: σz=30µm, N=3x1010e-, W: σz=10µm, N=1x1010e-, σr0=3µm, ∆z=115µm, ne=1017cm-3

Energy [GeV] Propagation Distance [cm]

  • Beam loading at 37GeV/m (z = 0)

Beam loading at 37GeV/m (z = 0)

  • After

After 80 80 cm plasma, gain cm plasma, gain 25 25 GeV with GeV with 3% 3% δ δE E/ /E E

  • Wake evolution due to bunch head erosion, but no dephasing

Wake evolution due to bunch head erosion, but no dephasing

  • Wake evolution

Wake evolution “ “bends bends” ” energy gain but preserves low energy gain but preserves low ∆ ∆E/E E/E

  • Drive to witness Energy transfer efficiency ~ 30%

Drive to witness Energy transfer efficiency ~ 30%

slide-20
SLIDE 20
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 20

slide-21
SLIDE 21
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 21

PWFA Collider PWFA Collider

  • Concept for a beam-driven PWFA collider (1TeV)

Concept for a beam-driven PWFA collider (1TeV)

– R&D: e+, emittance, efficiency

slide-22
SLIDE 22
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 22

FACET Beam is Well Suited for Studying FACET Beam is Well Suited for Studying DWA DWA

A ‘‘drive’’ beam excites wake-fields in the tube, while a subsequent witness beam (not shown) would be accelerated by the Ez component of the reflected wakefields (bands of color).

For large wakes want high charge, short bunches and narrow tubes, e.g. 2E10 e-, σz=20µm, Si with 200µm ID get 85GV/m surface fields!

slide-23
SLIDE 23
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 23

slide-24
SLIDE 24
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 24

1 GeV 1.5 TeV

slide-25
SLIDE 25
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 25

Other Proposed Research Other Proposed Research

  • Ultrafast processes in magnetic solids.

Ultrafast processes in magnetic solids.

  • Wakefield measurements of CLIC structures

Wakefield measurements of CLIC structures

  • Optical diffraction radiation tests

Optical diffraction radiation tests

  • Time profile of 50 fs bunches

Time profile of 50 fs bunches

  • Test of advanced Feedback Algorithms.

Test of advanced Feedback Algorithms.

slide-26
SLIDE 26
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 26

slide-27
SLIDE 27
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 27

slide-28
SLIDE 28
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 28

Other Research Considered Other Research Considered

  • Crystal Accelerator:

Crystal Accelerator:

– idea has been around for a while, inverse FEL process – at FACET could be done with high-energy photons

  • Crystal collimation and X-ray generation

Crystal collimation and X-ray generation

– use the strong bending in channeling to make Xrays – tried at other facilities (mostly e–: not efficient) – at FACET can use e+ & get to non-negligible intensities

  • Bragg diagnostics.

Bragg diagnostics.

  • Beam collimation studies

Beam collimation studies

  • High-gradient structure tests.

High-gradient structure tests.

slide-29
SLIDE 29
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 29

Crystal Channeling @ FACET Crystal Channeling @ FACET

  • Study of volume reflection of

Study of volume reflection of e e+

+ and

and e e–

–

– test continuum model of VR for light particles – study effect of multiple scattering on vr – possible application for halo cleaning in lin. colliders

  • Physics of volume-reflection radiation by

Physics of volume-reflection radiation by e e+

+ &

& e e–

–

– test radiation models for channeled light particles in region of undulator parameter K = E/m*Θ ≈ 1. – possible applicatin as new photon source

slide-30
SLIDE 30
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 30

9 mm Si Crystal, 400 GeV 9 mm Si Crystal, 400 GeV p p

Rotation angle (µrad) Angular profile (µrad)

de- channel volume capture Channeling Volume Reflection

slide-31
SLIDE 31
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 31

VR Simulation for FACET VR Simulation for FACET

Noble et al., CERN, 2009

slide-32
SLIDE 32
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 32

Crystal Collimation Crystal Collimation

p

Beam propagation Primary Primary halo (p) halo (p)

Absorber

  Coherent deviation of the primary halo

Coherent deviation of the primary halo

  Very small probability of inelastic interaction in the

Very small probability of inelastic interaction in the crystal crystal

  Larger collimation efficiency

Larger collimation efficiency

  Less impedance

Less impedance

  Reduced tertiary halo

Reduced tertiary halo

Crystal Beam Core Beam Core

  • E. Tsyganov & A. Taratin (1991)

α = O(100µrad) l = O(10-2 m)

slide-33
SLIDE 33
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 33 Carrigan, Channeling 2008

slide-34
SLIDE 34
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 34

X-ray Generation X-ray Generation

Bolognini, Thesis

180 GeV e– and e+

slide-35
SLIDE 35
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 35

Undulator Radiation possible? Undulator Radiation possible?

slide-36
SLIDE 36
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 36

Crystal Accelerator Crystal Accelerator

  • Idea: intense Xrays (40 keV, 10

Idea: intense Xrays (40 keV, 109

9 W) shone on

W) shone on crystal at Bragg angle setup accelerating field crystal at Bragg angle setup accelerating field

– channeled µ+ see accelerating field of GV/m – (Tajima & Cavenago 1987)

slide-37
SLIDE 37
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 37

Summary of non-WFA expts. Summary of non-WFA expts.

  • At FACET, we can

At FACET, we can

– Study collimation schemes for a linear collider

  • e+ and in particular e– as well
  • crystals may offer important advantages
  • extension of proton expts. at FNAL and CERN (UA9)

– behaviour of crystals at high intensities – Study the generation of X-rays by the extreme fields

  • equivalent to kTesla of magnetic fields
  • use e+: stronger effects than with e–
  • Possible to get coherent light?

– with sizeable intensities??

slide-38
SLIDE 38
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 38

Summary Summary

  • FACET will be a unique facility to advance the

FACET will be a unique facility to advance the high-gradient acceleration research with plasmas high-gradient acceleration research with plasmas and dielectrica and dielectrica

  • Beyond this, FACET will allow a number of

Beyond this, FACET will allow a number of advanced experiments in solid-state physics and advanced experiments in solid-state physics and the study of particle interaction with matter. the study of particle interaction with matter.

  • An open, proposal-driven process of experiment

An open, proposal-driven process of experiment approval will allow equitable access to the facility approval will allow equitable access to the facility to fore-front experiments to fore-front experiments

slide-39
SLIDE 39
  • U. Wienands, SLAC

LAL Orsay, 17-Sep-10 39

Apply Now! Apply Now!