Transcript Beam Delivery configuration materials to start discussion Andrei Seryi, Deepa Angal-Kalinin, Hitoshi Yamamoto BDS area GDE meeting at KEK, January 19-20, 2006

Beam Delivery
configuration
materials to start discussion
Andrei Seryi, Deepa Angal-Kalinin, Hitoshi Yamamoto
BDS area
GDE meeting at KEK, January 19-20, 2006
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
A.Seryi
2
19-20 Jan 06
ILC BDS baseline
•
•
•
•
•
•
A.Seryi
Magnets
Vacuum
Collimation and beam dumps
Instrumentations
Civil
RF, cavity package, cryomodule
3
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
19-20 Jan 06
Lengths, counts of magnets
(for present optics)
• Total length of beamlines
– 12008 m
• Counts of magnets (N Ltotal Laverage)
–
–
–
–
–
Bends:
Quads:
Sextup:
Octup:
Kickers
484
536
40
46
2*50
3375m
996m
39.6m
60.8m
200m
6.97m
1.86m
0.99m
1.32m
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
A.Seryi
4
19-20 Jan 06
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.
A.Seryi
5
19-20 Jan 06
Magnets (warm, SC, Pulsed, Special)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
A.Seryi
Long weak warm dipoles
Warm quads: cost driver: Large count
Warm quads
Magnet movers
Warm large aperture extraction quads
Kickers for fast extraction
Compact direct wind SC IR quads
IR quads:
Cost driver:
Compact direct wind sextupole/octupole IR packages
Unique and
Large aperture SC IR quads
difficult
Large aperture SC IR sextupoles
Octupoles for tail folding SC direct wind
Septa for fast extraction
Warm pocket coil IR quad
Muon walls:
Warm or SC super septum extraction quads
Cost driver:
Magnetized muon spoilers (9 and 18m iron walls)
large cost of
Detector integrated dipoles in detectors
material
IR antisolenoids
Related: power supply stability. Location of PS. Alcoves or surface bldg.?
6
19-20 Jan 06
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 be
one of costly items and need
to revisit strategy of their
implementation
• Staging? Start with min set and
add if #muons is too high?
• Alternatives
A.Seryi
7
Older NLC picture
19-20 Jan 06
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.
A.Seryi
8
19-20 Jan 06
e+ tunnel ?
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?
A.Seryi
9
19-20 Jan 06
Beam dump enclosures & service tunnels?
• Shafts?
A.Seryi
10
19-20 Jan 06
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?
A.Seryi
11
19-20 Jan 06
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?
A.Seryi
12
19-20 Jan 06
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 ?
A.Seryi
13
19-20 Jan 06
Instrumentation
• BPM and their channels
~ 1100
– Large aperture (r=3cm) – design issues
•
•
•
•
•
•
A.Seryi
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
14
19-20 Jan 06
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
A.Seryi
15
19-20 Jan 06
20/14mr
• BNL
• Issue of resources
at BNL
A.Seryi
16
19-20 Jan 06
Si D Forward Masking, Calorimetry & Tracking 2005-09-15
20mrad, L*=3.51m
E
HCAL
C
A
L
Muon Yoke
QD0
QF1
SD0
CRAB
Lo-Z
BeamCal
LumCal
Q-EXT
Support Tube
A.Seryi
17
19-20 Jan 06
Conceptual design of 2mrad IR
Shared Large Aperture
Magnets
SF1
QD0
SD0
Disrupted beam & Sync radiations
Q,S,QEXF1
QF1
Beamstrahlung
Incoming beam
60 m
pocket coil quad
Rutherford cable SC
quad and sextupole
A.Seryi
18
19-20 Jan 06
Details of zero degree design
Design of 20 & 2 mrad IR need to advance to and beyond this level of details
A.Seryi
19
19-20 Jan 06
10 01
55
00
-5 5-
-15 51-
-20 02-
-25 52-
-30 03-
-35 53-
-40 04-
• Large range
(3.5 times in volume)
• Parametric studies
of cost (~excavated
volume)
-10 0101 9 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 9 10
IR hall sizes
SiD: 48m x 18m x 30m
[SiD Collab. Mtg. 16-17 December 2005]
GLD: 72m x 32m x 40m
[Snowmass data]
A.Seryi
20
19-20 Jan 06
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
A.Seryi
21
19-20 Jan 06
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)
A.Seryi
22
19-20 Jan 06
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
A.Seryi
23
19-20 Jan 06