Status of the TESLA Magnet Package and Vibrations at TTF H. Brueck Dec, 6 2004

Topics The TESLA magnet package Current leads Prototype tests Results and plans of vibration measurements Dec 6, 2004 H. Brueck, DESY, MKS

Summary on TESLA Magnet Package Magnet is ready should arrive this week Aluminum Cylinder quadrupole gradient 63.5 T/m quadrupole current 100 A quadrupole inductance ~ 2.53 H dipole field 0.11 T dipole current 40 A dipole inductance ~29 mH max. field at conductor 3.22 T field length 0.52 m alignment error (angle) 0.1 mrad rms Connection plate side Dec 6, 2004 H. Brueck, DESY, MKS

Summary on TESLA Magnet Package Iron yoke blocks Superconducting coil Aluminum Cylinder Dec 6, 2004 H. Brueck, DESY, MKS

Summary on TESLA Magnet Package Coils and connection plate before it was assembled Dec 6, 2004 H. Brueck, DESY, MKS

Summary on TESLA Magnet Package Magnet is ready should arrive this week Warm and cold tests planed at DESY for December and January 05 Cryostat design done by a Spanish firm (TTM) Reviewed by CIEMAT, TTM will send drawings to DESY for a final review Fabrication at TTM until end of January 05 Two weeks for final assembly needed at CIEMAT Complete Magnet Package could be at DESY end of February 05 Future plans with the package Original foreseen for module 6 Now we propose to put it to module 10 (“FNAL module”) As this module will be assembled later, there would be time to send it to SLAC SLAC asked for a TESLA type magnet for measurements of the motion of the axis with respect to the beam when the field is varied We need to discuss how to proceed here (I’m at CIEMAT next week) Problem: one needs a special vacuum tank Dec 6, 2004 H. Brueck, DESY, MKS

Summary on Current Leads Prototype test at DESY, operated up to 150A Problem with cold feed through For the assembly in a module Ciemat has no HTS material available, checking if they can get more The “6 in one” assembly not yet designed, only the solution we are presently testing could be made I’ve contacted Mark & Wedell, that produces CERN 60A leads They are willing to give us one lead assembly (4 leads) out of the CERN production, but CERN has to agree No answer yet Dec 6, 2004 H. Brueck, DESY, MKS

Magnet Test Program at DESY Warm measurements (AC, low current) Harmonics Try axis and roll angle measurements (Stretched Wire) Followed by detailed cold test in a vertical bath cryostat (4K and 2K) cold harmonics with various currents and conditions finally quench tests Power supplies and electronics Test insert Warm finger and pick-up coil Dec 6, 2004 H. Brueck, DESY, MKS

Status from Vibration Measurements during shutdown (Sep 2004) Measurements at ACC 4 only Data acquisition close to sensors Two sensors (cold) at the quadrupole vertical and transverse to the beam Two sensors on top of the module Two sensors on the ground/support One geophone (vertical) at various places Measurements with various conditions Comparison Piezo - Geophone Day, night weekend Vacuum pumps on, off, pumps dismounted from trailer Dec 6, 2004 H. Brueck, DESY, MKS

Conditions PC now close to sensors Preamplifier switched from acceleration to velocity Implies a high pass at 1 Hz (.2 Hz in acc mode) Low pass filter at 1 kHz Data analysis Just FFT, ignoring non periodic effects, no corrections, no window-functions Averaging over many measurements Dec 6, 2004 H. Brueck, DESY, MKS

2 Piezos and a Geophone on the socket RMS average, Saturday midnight ± 1 hour Piezo blue and pink, Geophone red Good agreement between the two piezos piezo and geophone (20%) Low RMS: 34 43 45 nm for f>2Hz Comparable with ground motions measured by Ehrlichmann At low frequencies the noise signal is probably getting dominant 210804 2300 220804 0100 Dec 6, 2004 H. Brueck, DESY, MKS

Ground Vibration time dependence Friday to Monday, RMS f>2Hz Friday | Saturday | Sunday | Monday 100nm 20nm 15:00 20:00 1:00 6:00 13:00 15:00 20:00 1:00 6:00 13:00 15:00 20:00 1:00 6:00 13:00 Dec 6, 2004 H. Brueck, DESY, MKS

Comparison of Piezo and a Geophone on top of the module (vertical) RMS average, satuday midnight ± 1 hour Sensor positions on top of the module Good agreement, also Geophone and Piezo positions are not identical RMS: 115 nm for f>2Hz 2-3 time larger as at lower position (different weekend) Dec 6, 2004 H. Brueck, DESY, MKS

Check influence of the Pump stand Vibrations of the vacuum trailer generates a torque on the Schiebemuffe Long lever arm Vertical bellow fixed by bolts Dec 6, 2004 H. Brueck, DESY, MKS

Pump stand modifications Pump moved from trailer to floor Connected via a thin flexible line Frequency converter moved to the floor Internal dampers plus additional foam Dec 6, 2004 H. Brueck, DESY, MKS

RMS average, midnight ± 1 hour Pump stand without/with modifications Vertical Sensors (2 different days) RMS average, midnight ± 1 hour Sensors: Cold Top Socket Geophone Socket without with Different days Mon “without” Tue “with” Cold Signal *3 Some reduction below 25 Hz Large reduction between 25 and 50 Hz Dec 6, 2004 H. Brueck, DESY, MKS

RMS average, midnight ± 1 hour Pump stand without/with modifications Horizontal Sensors (2 different days) RMS average, midnight ± 1 hour Sensors: Cold Top Socket without with Different days Mon “without” Tue “with” Horizontal vibrations much larger Cold Signal *3 Some reduction below 25 Hz Large reduction between 25 and 50 Hz Dec 6, 2004 H. Brueck, DESY, MKS

Schematic View The horizontal vibrations are larger (about factor 1.5) Sensors on top The horizontal vibrations are larger (about factor 1.5) Cold mass essentially hanging Horizontal movements less constraint 300 mm tube Quadrupole Cold sensors Sensors on the socket socket Dec 6, 2004 H. Brueck, DESY, MKS

Present Summary Good agreement between the Geophone (our reference) and the Piezo in the frequency range from 2 to 100 Hz at various positions for averaged RMS and RMS vs. time Cultural noise day/night/weekend All in all data reliable Influence of vacuum pumps clearly seen Effect vanishes after modifications Pumps on/off not different anymore, which means Turbo pump has no effect Next step Excite module by forced vibrations using a motor with eccentric mass and tunable frequency Soft- und hardware prepared and tested at a HERA dipole Measurement schedule at TTF in shutdown in the week before Xmas Dec 6, 2004 H. Brueck, DESY, MKS

Forced Vibrations of a HERA Dipole Cryostat up to 20Hz Strong resonance observed at about 14.5 Hz Dec 6, 2004 H. Brueck, DESY, MKS

Forced Vibrations of a HERA Dipole Cryostat up to 60Hz Different measurements with decreasing eccenter mass Dec 6, 2004 H. Brueck, DESY, MKS

Forced Vibrations of a HERA Dipole Cryostat, RMS and Spectrum Dec 6, 2004 H. Brueck, DESY, MKS