FCC 14 Feb 2014 AB

1Experiment construction & machine interface

NB: preparatory group mission:

foster a structure of International Collaboration in each area so that

a well-balanced set of teams with global representation and experience can launch & execute the FCC design study

Some aspects of detector-machine interface are included in the draft FCC WBS structure

Following are to provoke discussion about the expt machine/infra interface

(including how the experimental facilities & sites integrate in the overall FCC picture) ie interface with Civil Engineering & the host lab infrastructure

Some later talks in this session consider specific issues (bunch spacing, radiation issues)

FCC 14 Feb 2014 AB

2Experiment Design Drivers

Physics objectives driving the experiment design (see Fabiola/Daniel at h-h session yesterday)

High p T region (up to ~ 2.5) : continue search for high mass states (up to ~50 TeV)

Aim for ATLAS-CMS-like momentum resolution at momenta 5-10 x higher~10% muon momentum resolution for a 20 TeV muon?~1-2% for 1 TeV charged pion ?

Magnetic field/ sensor resolutions not expected to change dramatically ~20% ?Contain showers from 1 TeV hadrons --> 12 deep calorimeter

Tracker radius x 2 system outer radius x 1.5

Forward region ( 2.5) : extend precision Higgs meas to high high mass VVForward spectrometer + calorimetry

dipole magnet + trackers + precision em cal + muon detectors to hadron calorimetry to Environment: Collision induced radiation field (fluences, induced dose rate and activation)

about a factor 2 higher than Hl-LHC (dependence principally on luminosity) see Werner’s talk this session

Magnetic fields & fringe fields remain a challenge

Hadron collider GP detectors wrt LHC expts

FCC 14 Feb 2014 AB

3Experiments designs

ATLASA Toroidal LHC ApparatuS

µ

CMSCompact Muon Solenoid

µ

ATLASA Toroidal LHC ApparatuS

µ

CMSCompact Muon Solenoid

µ

or

ATLASA Toroidal LHC ApparatuS

µ

CMSCompact Muon Solenoid

µ

ATLASA Toroidal LHC ApparatuS

µ

CMSCompact Muon Solenoid

µ

ATLASA Toroidal LHC ApparatuS

µ

CMSCompact Muon Solenoid

µ

+

ATLAS-like CMS-like

CMS

GEM much to learn from previous work for LHC & SSC+ ongoing work for high-lumi upgrades of LHC detectors

Magnetic bending ~ BL2 --> main driver for radial size of expt [ ]Length is more complicated (barrel coverage, eta reach & granularity etc)

FCC 14 Feb 2014 AB

4Remote Construction ?

Preferred model will be worldwide modular construction (as for LHC expts) by institutes or industry

Feasible for FCC expt dimensions??

Expt location/surface site should allow:

- Access for heavy, outsize & unusual loads

-direct routing of large components to site from manufacturer.

FCC 14 Feb 2014 AB

5+ local (re-)construction

assembly at host lab sites or expt sites (planned or in response to problems) - more than previous due to scale?

Availability of large host lab facilities essential for local construction, testing and storage.

Remote construction, test & deconstruction--> delivery to expt site for reconstruction.

FCC 14 Feb 2014 AB

6Surface buildings

Assuming GP expt sites are diametrically oppositeat least 1 site will need substantial autonomy

eg facilities for expanded resident team detached firefighter(s) + gear

Communications/tranport vs autonomy.

Adequate assembly hall(s) for surface pre-assemblyDetectors Services ready in time for surface pre-testing

powercooling (water + CO2)specialist gasesdetector environment control

Detector maintenance laboratories and workshops bearing in mind potential 50 year lifetime of site

Storage facilities for heavy assembly & maintenance tooling spares for local infrastructure equipment.

FCC 14 Feb 2014 AB

7Caverns & access shafts

Service cavern

Service cavern

How many shafts? - consider maintenance as well as construction - shared shafts between detector and service caverns? - shared shafts between experiment and accelerator?

As many services as possible on surface (power, cryo(?), pre—processing/triggering) -can the service caverns be smaller than at LHC?

Shielding should allow service cavern to be accessed during operations at max luminositySafety aspects (chicanes, ventilation, evacuation routes etc) are key to the design

Try to take account of all conceivable applications of the tunnel & caverns over 50 years eg exchange of whole expt conceivable or not?

FCC 14 Feb 2014 AB

8Caverns & shafts

Size & shape of detector caverns for General Purpose expts: (input to CE & LSS design & costing) is driven by : Experiment dimensions (barrel + endcap) based on chosen magnetic bending solutions for momentum analysis at high Pt

magnet/ detector configuration in the forward spectrometer

l * ( distance ip to 1’st machine element)

location & size of TAS or similar dual purpose protection elements shielding to reduce fluence of charged particles & neutronsbeam vacuum chamber (beampipe) & vacuum system (pump stations)infrastructure required in the detector hall (cable ducts & channels, local services)maintenance scenario

R. Tomas

FCC 14 Feb 2014 AB

9Caverns: plenty of experience

ATLAS (44m x 22m) Cavern: 55m x 35m x 40mabout 4 years

CMS (30m x 15 m) Cavern: 53m x 27m x 24mabout 6 years

SSC caverns

Excavation problems are again likely: Decoupling expt assembly from detector hall construction gives flexibility surface construction & heavy lowering :- viable for FCC hh expt size??

eg Toroid option: 50m x 30mEstimated cavern dimensions: 62m x 42m x 50m? challenge for Civ Eng.

FCC 14 Feb 2014 AB

10Cartoon cavern footprint ( eg Large Solenoid – DF talk)

60m 12m

30m

5m

# and size/shape of shafts and # and capacity of cranes need careful optimisation- depend very strongly on design & maintenance strategy of occupying experiment(s)

FCC 14 Feb 2014 AB

11Maintenance scenario cartoon (Large Solenoid)

60m 12m

30m

5m

shielded garage

shielded garage

Forward system (esp calorimeters) will become highly activated- heavy and precise transport systems needed to get forward system off beamline

FCC 14 Feb 2014 AB

12Cavern footprint- simpler version?

60m 12m

30m 10m

shielded garage

l* = 46m

ALARA considerations and integrated engineering for shieldingand remote handling will have to be built into the design from the outset.

FCC 14 Feb 2014 AB

13Radiation field

Engineering for better rad tolerance: detectors: good prospects human beings: unlikely

Emergency maintenance crews will encounter dose rates of few x 100 microSv/hr (x a few worse than at HL-LHC- detailed FLUKA simulations needed)

ALARA requirements must be engineered into FCC hh GP expts from the outset we will learn a lot from what we have to retroactively engineer for HL-LHC!

design for max 2mSv/yr/worker? rigorous choice of materials to minimise activation realistic full scale models kept updated for procedure development/practice RP monitors & traceability system built into personnel & material access control and equipment labelling quick-mount shielding, remote handling tooling, shielded bunkers

Detector services (source of most unplanned interventions with little cooling time) executed to a very high reliability & redundancy standard

FCC 14 Feb 2014 AB

14Experiment-machine interface

FCC hh initial parameters close to (or scaled from) HL-LHC ( for increased E beam)

creates synergies with HL-LHC studies and simplifies study of several issues of experiment design + allows direct experience to be carried forward

Key machine parameters for detector design (apart E beam): bunch structure bunch spacing: 25ns with option for reducing to 5ns

(out-of-time vs in-time pile-up, talk later this session)

bunch length: 8cm, possibly increased to 14 cm (pileup mitigation an issue, as for HL-LHC + pix

design) [luminous region ~ 7m x 57mm]

luminosity 5 x 1034 cm-2s-1 ( fluences, occupancy and radiation dose)

crossing angle 74rad at 25 ns ..what about 5ns ..(parasitic collisions?)l* (ip to 1st quad) 46m: no interference apparent …(TAS to be considered)

Will also have to understand abort gap –assume 80% of bunch slots are filled+ dump locations, abort delay etc, beam monitors,pathological beam scenarios and their consequences(not much of 8GJ needed to toast a detector)

FCC 14 Feb 2014 AB

15Looking forward

Brief: Investigate different options in all technical areas, taking a broad viewExpressions of interest over next few months (keeping single forum for now?)

Joint work needed between WBS categories : “Physics & Experiments” “Infra and Operations” “Accelerators”

Engineering Design, integration and simulation resources will soon be needed.(synergies with HL-LHC coordination and Project Office)

Radiation & magnetic field simulations fluences (with self service interpolation for detector designers) estimations of dose rates and activation levels for various lumi & cooling timesshielding design based on detector background & irradiation tolerancesestimation of beam induced backgrounds

must include magnetic field maps with detail extending to fringe fieldStudy of pile-up mitigation strategies eg wrt luminous region, bunch spacing etc.

Then…. Working groups to be set up in close contact with e-h and e-eexploiting synergies and potential common application.

FCC 14 Feb 2014 AB

16Possible evolution into hh detector WG’s

Initial break-out could be into somewhat coarser groups than those in the WBS eg….

Magnet design

Trigger DAQ, Controls & Computing

Barrel-endcap: Tracking, Calorimetry, muon identification

Forward: spectrometer and calorimetry.

Safety, Supporting systems, Infrastructure & Interfaces: eventually expanded into full WBS

safety and detector protectionradiation simulations, fluences, shielding, dose rates, activationcaverns and surface facilities detector construction, maintenance procedures & dose minimisationinterfaces to Accelerator, including

LSS beamline, bunch structure & luminous region, beam monitors,

pile-up mitigationbeampipe & vacuum systemetc