A Highly Automated Measuring System for the Lep Magnetic Lenses

The quadrupole and sextupole magnets o f LEP w i l l be measured by the harmonic c o i l method. I n order t o achieve precise, r e l i a b l e and r a p i d measurements o f the strength, f i e l d q u a l i t y and magnetic a x i s o f the lenses, a f u l l y autonomous, microprocessor c o n t r o l l e d system has been developed. Remote cont r o l o f the alignment o f the magnets on t h e i r measuring bench has been b u i l t in , thanks t o the use o f e l e c t r o n i c l e v e l gauges and o f a l a s e r beam as r e f e r ence axis. The l a t t e r i s used f o r p o s i t i o n i n g the reference ta rge ts o f the quadrupoles w i t h respect t o t h e i r magnetic axis. Design and performance o f the mechanical and e l e c t r o n i c equipment are presented.