CEA DSM Irfu SIS 9th stabilization meeting Status of pole tips measurement

CEA DSM Irfu Status Choice of the measurement device –Requirements –Tests results –Chosen sensor configuration Pole tips measurement on CERN mock-up (dec. 2010) –Measurement configuration –Solutions to be studied Preliminary tests at Saclay –Glue tests –Reflecting surface –Mechanical support –Measurement intent on IPHI mockup Planning 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)2

CEA DSM Irfu 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)3 Choice of the measurement device : requirements –Requirements : –Characteristics to be described Amplitude accuracy1nm and < Amplitude resolution0.1 nm and < Frequency range1 to 100 Hz Measurement frequency>400 Hz Maximum velocity1 m.s -1 Ability to cross a 60mm long hole in the yokeMax 6mm diameter Interferometer’s typeMichelson, Fabry-Pérot, Doppler… Acquisition systemAnalog/digit - I/O Other parameters acquisition requirementTemp, press, hygrometry, etc… Reflecting surfaceλ/? Reflection necessary for optimal measurement Measurement distance range0 to …? m Other requirementsProtection, vacuum conditions, influence of magnetic fields, etc…

CEA DSM Irfu 09/03/2010-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)4 Choice of the measurement device : tested sensors Instrument Characteristics RENISHAWATTOCUBESIOSPOLYTEC FIBER VIBROMETER INTERFEROMETER TYPE MichelsonFabry PérotMichelsonDoppler Differential modeYesNo Yes Distance measurement range 0 to 0.6m0 to >1m according to the sensor According to the sensor According to the focusing lens range Special requirement Protection from turbulences To be determined Cost (k€)70 to to to 60 ValidationNo YesNo

CEA DSM Irfu 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)5 Choice of the measurement device : POLYTEC fiber vibrometer tests results 100 Hz BadGood ampl 230nm ampl 16nm ampl 3.2nm ampl 190nm ampl 18nm ampl 1.9nm Capacitive senson Geophone Vibrometer 10 Hz Tests results on CERN bench (graphics by M. Guinchard) Impossibility to have a measurement result at 1 Hz : sensor rejected

CEA DSM Irfu Choice of the measurement device : chosen sensor configuration Available configurations 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)6 Commercial config. Reflector typeMax. speed Resolution (nm) Range measurement (mm) Connected sensors per acquisition unit Price (k€) Triple axis SP- TR λ/10 mirror to 1 according to working distance 0 à Adjustable focus LSV All type of reflecting surface à Mono-axis SPS All type of reflecting surface λ/10 mirror for max. resolution à 70, Chosen configuration (02/08/2010 meeting CR-MF/ a) : 3 axis working on differential mode or independently Angle measurement available ±0.3 mrad Beams distances 13mm I/O analogical or digital-32bit mode (atmosphere correction factor included on digital mode only)

CEA DSM Irfu 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)7 Pole tip measurement on CERN mockup : measurement configuration measurement on yoke 3- measurement on pole 2- measurement on pole (2-3) horizontal wave propagation on pole tip (1-2) and (1-3) vibration measurement between yoke and pole tip Measurement conditionsPurposeResults No controlled vibrationSee cultural noise influence on pole tips FFT spectrum Calibrated vibration on yokeSee propagation on yoke and poles FFT spectra and propagation diagrams Calibration vibration on girderSee girder’s influence on transmitting vibrations FFT spectra and propagation diagrams 3 measurement positions

CEA DSM Irfu Pole tips measurement on CERN mockup : solutions to be studied All tests can be performed before on a similar device at Saclay 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)8 Supporting sensor Drilling hole (angle and diameter) Reflecting surface (glued or polished?) Girder and actuators for controlled movements

CEA DSM Irfu Preliminary tests at Saclay : glue tests and reflecting surface choice Purpose : –Verify that no damping due to the glue alter the displacement measurement –Choose the glue type (wax, araldite, other?) –Time effects on glue –Test : 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)9 Signal comparison OK : mirror glued NO: surface to be polished

CEA DSM Irfu Preliminary tests at Saclay : mechanical support design Mechanical problemOption chosen for Saclay test Vibrometer supportGlued or tightened on the yoke or independent Reflecting surface mountingMirror glued on an invar made wedge Hole drilled in yokeØ3mm wished, test on a vibrometer next Thursday 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)10

CEA DSM Irfu Preliminary tests at Saclay : measurement intent IPHI mockup 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)11 Reflecting surface and glue tests Vibration transmission tests Sensor mechanical interface Hole diameter test

CEA DSM Irfu 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)12 Planning TaskJFMAMaJuJAoSONDJFM Sensor bought and delivered Reflector and sensor tests Mechanical interface design Measurements on IPHI mockup Design and fabrication of mechanical interface for CERN mockup 1 point measurement on CERN mockup N points measurement on CERN mockup

CEA DSM Irfu Next steps Hole diameter test on Thursday Sensor device order march-april Sensor delivery 12 weeks after (?) Mirrors and wedges bought in march 25/09/2008-MichelFontaine- CLIC Stabilisation ("pied de page" et "date" -> onglet menu Affichage/En-tête)13