beam delivery configuration materials to start discussion

Beam Delivery configurationmaterials to start

discussion

Andrei Seryi, Deepa Angal-Kalinin, Hitoshi YamamotoBDS area

GDE meeting at KEK, January 19-20, 2006

19-20 Jan 06A.Seryi 2

Progress• RDR work

– Contacting Technical systems (Magnets, Vacuum, Instrumentation, etc) to establish communication and define scope the work

– Start to estimate and request needed resources

• Design work– Continue design optimization, e.g. – Finalize optics for tune-up extraction and diagnostics– Consider improvements in 2mrad extraction chicanes

(0.7MW SR loss at 1TeV CM)– Will consider low power tune-up dumps– Technical consideration of push-pull requirements– Radiation physics study for single IR hall; self shielded

detector; MPS– design for 1TeV compatibility– Any design changes will go through CCB


ILC BDS baseline

• Magnets• Vacuum• Collimation and beam dumps • Instrumentations• Civil• RF, cavity package, cryomodule

Layout and counts are accurate to better than 10% : anticipate very small change of optics in diagnostics and fast extraction. If will go e.g. to single dump and add a beamline to the main dump – could have some effects on the count as well


Lengths, counts of magnets (for present optics)• Total length of beamlines

– 12008 m

• Counts of magnets (N Ltotal Laverage)– Bends: 484 3375m6.97m– Quads:536 996m 1.86m– Sextup: 40 39.6m 0.99m– Octup: 46 60.8m 1.32m– Kickers 2*50 200m 2m

• Total length of magnets (active length)– 4673 m

• Active / Total length– 38.9 %– This number (active/total) is underestimation, e.g. length

of BPMs is not included (if stick out of magnets) or other instrumentation


Vacuum system• Total length of vacuum system ~12km

– about 7500m of drifts with simple vacuum chamber– about 3400m are in bends with moderate SR. Design of chamber

need to be evaluated– Several chicanes in extraction with high SR losses. Special

chamber design will be needed.• About a thousand of quads and bends and about a thousand of

BPMs, with associated vacuum connections • There is instrumentation which require optical windows • The aperture ranges from couple of cm to half a meter in some

places in extraction line• Vacuum requirements, about 10nTorr near IR (tbc)• The need for fast valves in several places (e.g. near dumps)• Perhaps one of the biggest single cost items in BDS• Other (minor) questions

– narrow gaps from collimators take into account in conductance eval.

– Specific requirements for vacuum readout for MPS and BDS diagnostics ?

– Accel. phys. tech. group to contacts e.g. for vacuum req. reeval.


Magnets (warm, SC, Pulsed, Special)• Long weak warm dipoles• Warm quads• Magnet movers• Warm large aperture extraction quads • Kickers for fast extraction • Compact direct wind SC IR quads • Compact direct wind sextupole/octupole IR packages• Large aperture SC IR quads • Large aperture SC IR sextupoles• Octupoles for tail folding SC direct wind • Septa for fast extraction• Warm pocket coil IR quad• Warm or SC super septum extraction quads• Magnetized muon spoilers (9 and 18m iron walls)• Detector integrated dipoles in detectors• IR antisolenoids• Related: power supply stability. Location of PS. Alcoves or

surface bldg.?

Warm quads: cost driver: Large count

IR quads:Cost driver: Unique and difficult

Muon walls:Cost driver: large cost of material


Muon spoilers• Two magnetized walls 9m and

18m in each branch• Needed to reduce muon

flux at IP to below 10muons per 200 bunches

• Assume 0.001 of beam lost at collimators

• Muon spoilers seem to beone of costly items and needto revisit strategy of theirimplementation

• Staging? Start with min set and add if #muons is too high?

• Alternatives

Older NLC picture


Muon spoiler material cost estimation• 4m*5m (9m+18m) * 4branches * density 8Ton/m3

* 3.3$/kg = 57M$ for the material only• References for iron cost (range from 2.2$kg to

3.5$/kg):– 1) M.Breidenbach et al: 3.48$/kg – SiD muon system

(Babar Kawasaki experience. M.B.: “Note iron is a commodity with big fluctuations”)

– 2) L.Keller: raw material=0.7$/kg, fabrication=1.5$/kg, total=2.2$/kg

• probably obsolete data

– 3) F.Asiri: material $1000/ton in US. Cost of prepared, cut, crated and delivered to order is about $3,300/ton. Korean Iron may be purchased for about 30% less in US.


Civil layout ?s• Location of shafts (8?)

– at each dump (6) and IP (2) ?

• Location of positron go-around tunnel

• Do we need service tunnels?

• Alcoves for electronics?• Location of power

supplies?

Shaft also here?

Service tunnels?

e+ tunnel ?


Beam dump enclosures & service tunnels?• Shafts?


Drawings and other misc. questions• Drawings like those CF layouts shown in previous

page – should they be provided to all GDE on password protected web site?

• Are there global guidance on what cranes or other transportation machines will be available in the halls, alcoves and in the tunnel? – e.g. if we need to move 12m long magnet, or remove

collimator, what is the procedure? Is there global guidance on limits for sizes of components?


Beam dumps and collimations• Full power dumps (18MW) (6)

– Removing tune-up dumps will be considered

• Photon (~1-3?MW) dumps (2)• Fixed aperture protection

collimators (~60)• Adjustable spoilers and absorbers (~60)• Passive devices to limit betatron aperture (to be

designed)• Forming the task force to estimate beam dump cost

and understand importance of site and ground water

• Beam Dumps and Collimation technical system – 1 name out of 3. Very big issue. Can we solve it in 48hours?


RF, cryomodule, cavity package systems• Crab cavity systems• Based on 3.9GHz deflecting mode cavity

developed at Fermilab– Present 3.9GHz CKM cavity not suitable as prototype – it

is mechanically too soft, its frequency is 3.925GHz, etc.

• Experience with 3.9GHz accelerating mode cavity is also relevant

• Fermilab is best positioned to make RDR design and cost estimation, as well as start work on real crab cavity design and prototype, to be built in ~1.5 years

• Coordination with UK colleagues and work sharing need to be discussed. E.g. cavity itself – Fermilab, phase stabilization system – UK ?


Instrumentation• BPM and their channels ~ 1100

– Large aperture (r=3cm) – design issues

• Laser wire systems• Current monitors, loss monitors (standard)• Feedbacks and fast luminosity monitors, pair

monitor• Spectrometer and polarimeter upstream &

downstream• Alignment – Civil group & Instrumentation• This week at SLAC – mtg of Instrumentation

technical group for discussion of feedbacks in BDS etc


IR systems and magnets• Unique, difficult magnets, integration with

detectors, R&D• One of the high cost items (~ X0M$ ?)• Do not have sufficiently detailed sketches that

would allow to make technical and engineering evaluation

• One of concerns and the area where trying to pull in resources

• 20(14)mrad IR magnets – design and cost estimation by BNL

• 2mrad IR magnets – design and cost estimation by Fermilab and Saclay

• IR instrumentation, LUMI/BEAMCALs, IP BPMs, kickers


20/14mr• BNL• Issue of

resources at BNL


Si D Forward Masking, Calorimetry & Tracking 2005-09-1520mrad, L*=3.51m

Q-EXT

CRAB

QF1SD0QD0

ECAL

HCAL Muon Yoke

Support Tube

Lo-Z

LumCal

BeamCal


QD0SD0 QF1

SF1 Q,S,QEXF1

Disrupted beam & Sync radiations

BeamstrahlungIncoming beam

60 m

Shared Large Aperture Magnets

Rutherford cable SC quad and sextupole

pocket coil quad

Conceptual design of 2mrad IR


Details of zero degree design

Design of 20 & 2 mrad IR need to advance to and beyond this level of details


-40 -35 -30 -25 -20 -15 -10 -5 0 5 10

01

23

45

67

89

10

IR hall sizes

GLD: 72m x 32m x 40m [Snowmass data]

SiD: 48m x 18m x 30m [SiD Collab. Mtg. 16-17 December 2005]

• Large range (3.5 times in volume)

• Parametric studies of cost (~excavated volume)


Cost of BDS• Two approaches should give about the same

answer– Bottom -> top approach (count parts, individual cost)– Top -> bottom (compare with recently built accelerators,

scale, and adjust for differences)

• With exception of special systems, whose cost could be added, BDS is a lot of kms of warm magnets and vacuum chambers

• It should be possible to compare it, for example, with Main Injector cost, scale according to beamline length, length of magnets and add special costly systems (beamdumps, muon walls, IR halls, IR and FD)– There are many caveats (e.g. more precise power

supplies could be more expensive) but top-bottom cost should also give correct answer


Possible cost saving strategies• Singe IR (will be chosen when more design and cost

information will be available, in ~5month)• Install only fraction (half) of bends at 500GeV CM stage

– this will increase difficulty and cost of the energy upgrade

• Design all quads as consisting from two halves and install only one half at 500 GeV CM– same difficulty with upgrade

• Replace high power tune-up dumps with low power– additional beamline from BDS entrance to main dump => +cost

• Consider staging construction and installation of muon walls (e.g. start with min 5m wall). Install more if muon rate is too high– May be difficult to install the wall in operational tunnel – Consider alternative muon spoilers

• Undisrupted beam size at dump window - rely not on drift but more on rastering - shorten extraction lines (MPS)


Some milestones• Feb 13-14, GDE mtg at Fermilab – review BDS

optics• Bangalore

– one more iteration on IR comparison– first report on technical evaluation of push-pull?– evaluation (e.g. rad. physics) of single IR hall– more details on upgrade paths from single IR– including consideration of upgrade to gamma-gamma

• Will set up review of beam dump cost and design – end of March?

• End of May – full picture of IR performance and cost– possibly, that is when will choose the favorite IR design

beam delivery configuration materials to start discussion

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