The FiDeL Project

L.Bottura

following several, long brainstorming sessions with

L. Deniau, J.P. Koutchouk, M. Lamont, N. Sammut,

L. Walckiers, R. Wolf

MARIC - March 1st, 2006

Outline Context Aim of the FiDeL project FiDeL Concept Generation of sets of parameters Use of FiDeL AT involvement Project definition

Reminder: magnetic re-set cycles

magnetic databases

survey database

geometry database

LHC layout

optics definition

magnet sequence

virtual LHC (MAD)

LHC control system

LHC configuration databases

magnetic field data

geometry data

survey data

magnetic field trims

geometry trims

survey trims

field model

field model

The helicopter viewAB ?

TS-IC

AT-MASAT-MELAT-MTM

AT-MASAT-MTM

TS-SU

TS-SU

AB-OP

AB-ABP

AT contribution

FiDeL

Background On magnetic references for the LHC:

No need to have reference magnets in the tunnel (DEWG 1996) Idea of a magnetic reference for the LHC including a magnetic

model (COOP Forum, December 1999) No need to have reference magnets (RMS Review, July 2004) Field Model definition (Chamonix 2005, PAC 2005)

On models for beam optics: MAD model including measured field errors (AB-ABP & al., 2005) MAD model including measurement uncertainties (Chamonix

2006) On LHC control:

Field Model specifications included in a prototype of the ramp generator (Chamonix 2006)

Aim of the FiDeL Project A Field Description of the LHC to:

Describe the magnetic state of the LHC Provide settings in the main magnets (MB, MQ,

MQM, MQY, MQXx) and in the corrector circuits to prepare the LHC for injection, program the ramp, and reach known and corrected coast conditions

Provide trims for correction circuits during constant current plateaus, and especially to follow the field drift at injection

Provide trims for correction currents during the energy ramp, and especially during the snap-back at the beginning of the acceleration

FiDeL Concept Field Model

Unified description of the field and field errors Cn applicable to all LHC magnets

Set of parametric equations for 7 physical components

Geometric Persistent Saturation Residual magnetization Decay Snap-back Ramp

Field parameters Adapt the parametric equations

to fit the measured or expected behaviours of the magnets

Set of ≈20 parameters, classified in 2 categories:

Shape parameters, equal for all magnets of the same type and family (e.g. all MB’s with inner cable 01B)

Amplitude parameters, specific to each magnet (e.g. geometric Cn)

FiDeL

Phys.Rev. Special Topics, Accelerators and Beams, 9, 012402, 2006

Generation of parameters

cold MM

correctors warm MM

produce list of slots for the given circuit

produce list of magnets for the given cicuit

retrieve magnetic model parameters for each magnet in the circuit

integrate model parameters over the

circuit

Circuit Parameters

Magnet Parameters

circuit_ID

circuit_ID,{slot_ID}

circuit_ID,{slot_ID, magnet_ID}

circuit_ID,{slot_ID, magnet_ID, parameter_set}

circuit_ID, parameter_set

dictionary of magnet type and magnet family

magnet_ID

magnet_ID, magnet_type, magnet_family

Field Parameters

p pmagnet_family,

magnet_ID

circuit

{slot_ID}

slot_ID

magnet_ID

magnet_type, magnet_family,

pmagnet_family, magnet_ID

main ring warm MM

parametrization of field data

LHC layout

MTF slots

2. tools to build and store the

LHC configuration

1. synthesis of measured data

3. generation of the

parameter set

Use of FiDeL - LHC control

Circuit Parameters

Generate ramp for

main ring magnets

Bm / Im

Cn(I,t,dI/dt,I(-t))

Im / cn

Cn(I,t,dI/dt,I(-t))

Bn / In

Cn(I,t,dI/dt,I(-t))

Optics

Error forecast

Generate ramp for

corrector magnets

Bm(t) Im(t)Im(t) cn(t) Bn(t) In(t)

correctionstrategy

Use of FiDeL - Optics studies

Magnet Parameters

Ramp setting

Bm / Im

Cn(I,t,dI/dt,I(-t))

I / cn

Cn(I,t,dI/dt,I(-t))

Optics

Error forecast

Bset(t) I(t)Iset(t) cn(t)

ILHC(t)

MAD

AT involvement Short term (2006 to sector test/commissioning)

Define and validate the model Create a common data structure Collect, prune, and complement data for all magnet types Generate the configuration sets from the circuit and machine layout

Medium term (2007-2008) Participate in the implementation and test of the LHC configuration and

control system Prepare for commissioning through studies of the effect of magnetic

uncertainties (within the scope of FQWG) Adapt the parameters sets and create parameters trims tables during

sector test/commissioning Define, perform and analyse measurements on off-line benches in SM-

18 (see: FaMe) Long term (> 2008)

Maintain data structures, tools and settings Participate/motivate MD and dedicated field measurements to optimise LHC

operation

FiD

eLA

T ?

When ? Proposal based on validation test during

sector test

Who ? Mandate the FQWG to

Complete the definition of the project (interfaces, responsibilities, deliverables)

Compile above in a RDD to be agreed with AB-OP (LHC controls) and AB-ABP (MAD)

Propose participation of AT groups (MEL/MAS/MTM are natural candidates)

Provide the structure for coordination and follow-up of progress

Spin-off the team that will be in charge of the LHC magnetics

Topics for discussion OK on the short and medium term ?

Clarify the frame for the long term contribution of AT to the LHC operation and optimization, to provide a defined boundary for the exploitation of FiDeL

FiDeL “components”

Seven components of different physical originto describe the field and field errors

In addition: residual magnetization and ramp (not visible above)

MB parameters for sector 7-8

Work in progress for decay/SB parameters

Integrated B1 in sector 7-8

Aim: Bdl = 1189.2 Tm for injection at 450 GeV

Iterate:

Bdl/154 = TF(I) Iset

Result:

TF = 10.118(0) Tm/kA

Iset = 763.2(0)

Plan for main optical elements in sector 7-8

Plan for correctors/trims in sector 7-8