2001

Measurement and Analysis of the Field Quality of the LHC Prototypes and Pre-Series Superconducting Dipoles - S. Sanfilippo[Geneva/MT17/27/09/2001]

We report the main results of the magnetic field measurements performed on the full-size LHC superconducting dipoles tested at CERN since summer 1998. Main field strength and field errors are summarised. We discuss in detail the contributions related to the geometry of the collared coil, the
assembled cold mass, cool-down effects, magnetisation of the superconducting cable and saturation effects at high field. Dynamic effects on field harmonics, such as the field decay during injection and field errors during current ramps, are assessed statistically. PDF

 2000

Dynamic Effects in the Magnets - L. Bottura [CERN/MAC, 01/02/2000]

Dynamic effects will be one of the major issues for the operation of the LHC. Dynamic effects are generated mostly by cable coupling (eddy) currents and by the multipoles decay and snap-back at the end of injection. This presentation describes the  phenomena, showing the order of magnitude expected in the LHC. The major part of the presentation concerns the physics understanding of decay and snap-back and the state-of-the-art of our knowledge. Based on the present knowledge we are envisaging a correction scheme based on a magnetic reference (including reference magnets, database tables and non-linear scalings) that will be used to power corrector circuits in the LHC. PDF
 

Warm magnetic and axis measurements of MBPN1 with the MTA mole - Marco Buzio, Nikolay Smirnov  [LHC Special Seminar, 07/04/2000]

This talk presents the results of room temperature measurements of MBP2N1 carried out in SM18 with the new LHC/MTA rotating coil travelling probe (mole). The mole, which performs near-simultaneous magnetic measurements of field quality and optical measurements of coil position, can be used to measure the magnetic axis of a dipole in both normal or QCD configuration. The measurements obtained are compared with previous results from LHC/MTA 15m benches, as well as with independent magnetic (LHC/MMS) and geometric (EST/SU) measurements. The mole performance quality and future use for series tests are discussed. PDF-part1, PDF-part2

 1999

Finding magnetic axis of LHC superconducting magnets in warm conditions - L. Deniau[BNL/IMMW99, 23/09/99]

Presentation of a method used to improve the accuracy of magnetic measurements using rotating coils systems at low field. The method is based on powering the magnet with AC while the coils rotate. PDF

Effect of rectangular coil windings on magnetic field measurement using rotating coils system- L. Deniau [BNL/IMMW99, 21/09/99]

Presentation on the error introduced by rectangular coil windings on magnetic field measurement using rotating coils systems. PDF

Off-line data analysis - L. Deniau [CERN, 19/01/99]

A short presentation on the status of the data off-line analysis environment for magnetic measurements made in the CERN LHC/MTA group. PDF

Rotating coils - L. Deniau [CERN, 18/01/99]

A short course on the magnetic induction principles and on the rotating coil system used for the magnetic measurements made in the CERN LHC/MTA group. PDF

 1998

SL++, A C++ Scientific Library - L. Deniau [CERN, 29/09/98]

A short presentation for the LHC++ Workshop. PDF