THE LEP MAGNET SYSTEM

L. Resegotti
1984 Le Journal de Physique Colloques  
A f t e r a b r i e f review o f the LEP p r o j e c t , the magnet system i n the main r i n g i s described. Special a t t e n t i o n i s devoted t o t h e dipoles and t o the magnetic lenses o f the l a t t i c e , which have t o be produced, measured and i ns t a l l e d i n l a r g e numbers and a t h i g h rates. The construction techniques which have been developed i n order t o meet the physical requirements i n the most economic way and the experience acquired w i t h model prototypes
more » ... are presented. The s o l u t i o n s adopted f o r s e r i e s production c o n t r o l and f o r t h e magnetic measurements are reported. The expected schedule o f manufacturing and i n s t a l l a t i o n i s mentioned. I -INTRODUCTION LEP, the Large Electron-Positron c o l l i d e r under c o n s t r u c t i o n a t CERN 111, has a c i rcumference o f 26.659 km and i s l o c a t e d i n an underground tunnel i n the region between the piedmont o f t h e Jura and the Geneva a i r p o r t , s t r a d d l i n g the border between France and Switzerland. The f i r s t phase, which i s now authorized, w i l l i n v o l v e t h e construct i o n o f the complete magnet and vacuum systems and s u f f i c i e n t radiofrequency t o s t o r e beams o f e l e c t r o n s (e-) and p o s i t r o n s (e4) up t o an energy of between 50 and 60 GeV. The possible f u t u r e a d d i t i o n o f more equipment would enable the storage o f beams o f higher energies up t o a maximum o f 125 GeV b u t such a d d i t i o n s would r e q u i r e f u r t h e r a u t h o r i z a t i o n fromtheCERN Member States. The tunnel [21 l i e s i n a plane i n c l i n e d by about 1.5 % w i t h respect t o the horizontal and i t s average depth i s about 90 m. It c o n s i s t s o f e i g h t arcs, where i t has a d i ameter o f 3.76 m (Fig. l ) , i n t e r l e a v e d w i t h e i g h t s t r a i g h t sections. C o l l i s i o n s o f f o u r e l e c t r o n bunches and f o u r p o s i t r o n bunches may be obtained and e x p l o i t e d f o r experiments a t e i g h t " i n t e r a c t i o n p o i n t s " i n the middle o f t h e s t r a i g h t sections. However, only f o u r experimental areas, a t t h e even points,
doi:10.1051/jphyscol:1984147 fatcat:kgyvxllj6farxhgmquswenaqse