Global Design Effort Beam Delivery System & Machine Detector Interface Andrei Seryi, SLAC Annual DOE HEP Program Review June 11-14, 2007

Global Design Effort

Beam Delivery System &Machine Detector Interface

Andrei Seryi, SLAC

Annual DOE HEP Program Review

June 11-14, 2007

Global Design Effort BDS & MDI: 22007 DOE review

Plan of the talk

• Overview of Beam Delivery System design

• Highlight contribution of SLAC team to RDR design of practically all subsystems of BDS

• Describe ATF2 and ESA facilities and SLAC role

• Show integration of SLAC and Americas efforts into global efforts on Beam Delivery


BDS layout

• Single IR push-pull BDS, upgradeable to 1TeV CM in the same layout, with additional bends

• Design of central area is done with major contribution from SLAC CFS group


BDS beamline

14mr IR

FF

E-collimator

-collim.

Diagnostics

Tune-up dump

BSY

Sacrificial collimators

Extraction

grid: 100m*1m

• SLAC experience with SLC and FFTB allow SLAC to contribute to various aspects of ILC BDS design • Optics design of BDS beamlines done almost entirely at SLAC


BDS optics for incoming beam

FF

E-c

ollim

ator

-collim.Diagnostics

BSY

Pol

arim

eter

E-s

pect

rom

eter

• FF optics is based on a local chromaticity compensation design suggested at SLAC


Machine Detector Interface

• Strong expertise on MDI issues at SLAC– beam background– Luminosity, E, and polarization diagnostics– machine detector integration

• Will show two examples where, during RDR design optimization, the MDI issues were analyzed, with significant participation of SLAC group, and design changes suggested, resulting in large cost saving or schedule improvement– muon protection– detector assembly


Muon walls

Analysis of detector background for likely beam halo have shown that initial installation can include single 5m walls, which gave significant saving w.r.to initial configuration of 9+18m walls.

Have space to install second 9m wall and upgrade 5m wall to 18m if background level will be measured to be too high.

• Purpose:– Personnel Protection: Limit

dose rates in one IR when beam sent to other IR or to the tune-up beam dump

– Physics: Reduce the muon background in the detectors

Magnetized muon wall


photos courtesy CERN colleagues

Detector assembly

• CMS detector assembled on surface in parallel with underground work, lowered down with rented crane

• Adopted this method for ILC, to save 2-2.5 years that allows to fit into 7 years of construction

• This also allowed to optimize & reduce CFS EXP cost

• SiD and other detector concepts implementing this strategy into their design


IR integration

• Integrated design of Interaction Region will be one of the main focus points of SLAC activity in EDR

• IR integration design work will be done in collaboration with BNL, developing IR SC magnets, and with Detector concepts

• Single IR push-pull configuration pose specific challenges to this work

• Goal is to evolve from concept level cartoons, shown on next slides, to cost and performance optimized detailed engineering design


IR integration, a start

(old location)

• Started IR integration work at SLAC, in close collaboration with BNL and other partners


• Design and prototyping of IR compact SC magnets is led by BNL (Brett Parker et al)

• Accelerator physics optimization of IR magnets is done in very closed and fruitful collaboration of BNL and SLAC

Shield ONShield ON Shield OFFShield OFFIntensity of color represent value of magnetic field.

Actively shielded QD0

to be prototyped

new force neutral antisolenoid


IR integration

For IR integration, a task force was formed with BNL colleagues and SLAC cryo and mechanical engineers & physicists. With emerging EDR organization, this task force will be streamlined

Service cryostat & cryo connections

BNL


Workshop on ILC Interaction Region Engineering Design SLAC, September 17-21, 2007

• Goal: To review and advance the design of the subsystem of the Interaction Region of ILC, focusing in particular on their integration, engineering design and arrangements for push-pull operation.

• … goal is to make progress on the design of the ILC IR through focused preparation before and during the workshop…

• The International Program and Advisory Committee is being formed. Its charge includes organization of preparatory work before the workshop and production of conceptual solutions and drawings that could be further discussed and reviewed at the workshop… – this is an attempt to align the organization of the workshop with

EDR organization

http://www-conf.slac.stanford.edu/ireng07/


BDS subsystems & test facilities

• Several subsystems of BDS will require focused work & prototypes in EDR phase – IR magnets, crab cavity, beam dump, collimators…

• BDS system test – ATF2 facility at KEK• BDS/MDI facility – ESA at SLAC

• SLAC team is involved in major part of these activities

• Overall system design, system engineering and integration will be major


Evaluation of different designs and optimization of couplers to reduce sensitivity to notch filter gap (Z.Li et al, SLAC)

old / newHOM coupler

Crab cavity design

3.9GHz 9-cell cavity in Opega3p, (K.Ko et al, SLAC)

•Challenges:•LLRF phase and synchronization stability

–Required phase stability ~67fsec or 0.094o for <2% luminosity loss (7 cell 1.5GHz cavity at the JLab ERL achieved a 37fsec)

• Couplers, tuning, cryomodule • Design & EDR work will be done by UK-FNAL-SLAC collaboration

3.9GHz cavity achieved 7.5 MV/m (ILC operating field at 500GeV/beam is 5MV/m (FNAL)


Beam dump

• Design is based on MW dump designed and built at SLAC

• ILC beam dump features– 17MW power; rastering of the beam on 30cm double

window; upstream donut collimators– 6.5m water vessel; 1m/s flow; beam 0.3m off-center; 10atm

prevent boiling; – three loop water system; catalytic H2-O2 recombiner; filters

for 7Be; – Shielding 0.5m Fe & 1.5m concrete

• EDR work will include physics & engineering design, studies of window irradiation and possibly prototyping the front-end of the windows exchange mechanism


ATF2

Scaled down model of ILC final focus


ATF2 facility

• ATF2 will: – prototype FF– help development tuning methods, instrumentation (laser

wires, fast feedback, submicron resolution BPMs), – help to learn achieving small size & stability reliably, – potentially able to test stability of FD magnetic center.

• ATF2 is one of central elements of BDS EDR work, as it will address a large fraction of BDS technical cost risk.

• Constructed as ILC model, with in-kind contribution from partners and host country providing civil construction

• SLAC contributions to ATF2 include– Design of optics; high availability PS; magnets for FD; bends;

electronics for BPMs; movers for magnets; – commissioning & operation

• ATF2 commissioning will start in Autumn of 2008


J.Nelson (at SLAC) and T.Smith (at KEK) during recent "remote participation" shift. Top monitors show ATF control system data

ATF & ATF2

T.Smith is commissioning the cavity BPM electronics and the magnet mover system at ATF beamline


BDS beam tests at ESA

Runs: three 2-weeks runs in 2006 & 07;request two runs in 2008

Latest run: March 7-26, 2007~ 40 participants

BPM energy spectrometer (T-474/491)Synch Stripe energy spectrometer (T-475)Collimator design, wakefields (T-480)IP BPMs/kickers—background studies (T-488)EMI (electro-magnetic interference)Bunch length diagnostics (T-487)

more in talk of M.Woods


interferometer

Energy spectrometer at ESA

• BPM & SR based

• Interferometer metrology grid for BPMs

• NMR probes in magnets

• 0.5um BPMs with =5mm => 1e-4 energy resolution

• Study calibrations, systematics, stability

• SR version with quartz fiber detector will be used next run

BPM

magnet of the chicane


Collimation wakefield study in ESA

• Results from 2006 run: – measurements, analytics & 3d modeling differ by up to factor of 2

• March 2007 run was focused on tests of – importance of tapers in region away from gap center– tapers with shallow part only near beam axis– explicit tests of surface roughness– non-linear exponential form taper

• Results are being analyzed


Integration of SLAC efforts

• SLAC efforts are integral part of Americas efforts on BDS design

• Main collaborators in Americas are BNL and FNAL– contacts with TRIUMF are being established– Universities contribute to MDI experiments

• Americas efforts are well integrated into worldwide efforts on BDS– optimization of work distribution is being

done, with help of BDS area leaders and GDE S4 task force


R&D in BDS and global collaboration

• Development of IR SC magnets, integration into the IR, design study to ensure their mechanical stability. US only, US lead

• development of crab cavities, and related systems to provide phase stability. US in collaboration with UK as equal partners

• design, construction, commissioning and operation of BDS facility (ATF2). US in collaboration with Asia and Europe, Asia lead

• accelerator physics design work which enable performance optimization. US in collaboration with Asia and Europe, US lead

• measurements of collimator wakefield and their validation with codes. US in collaboration with UK, UK lead

• study of collimator beam damage and damage detection. US in collaboration with UK, as equal partners

• development and tests of MDI type hardware such as energy spectrometers. US in collaboration with UK, as equal partners

• Development of laser wires for beam diagnostics. No significant US involvement, UK lead.

• development of intratrain feedback. No significant US involvement, UK lead

• design of beam dumps. US, Canada (discussed) & UK as equal partners


Summary

• Beam Delivery System design was produced for RDR, with significant contribution from SLAC team

• SLAC group critically involved in many subsystems of BDS and into machine detector integration

• SLAC and Americas efforts are well integrated into global efforts on Beam Delivery

• SLAC is ready to take the leadership role in the design, construction and operation of Beam Delivery System area of ILC

Documents

Global Design Effort Beam Delivery System & Machine Detector Interface Andrei Seryi, SLAC Annual DOE HEP Program Review June 11-14, 2007