A LOW GRADIENT TRIPLET QUADRUPOLE LAYOUT COMPATIBLE WITH NbTi MAGNET TECHNOLOGY AND β * = 0.25m *
The paper presents a triplet layout option with long (about 100m total triplet length), low gradient (45T/m to 70T/m) quadrupole magnets. Assuming a maximum magnet diameter of 200mm, the peak coil field at the magnet coils still remains below 7T which is still compatible with conventional NbTi magnet technology. The peak beta function inside the triplet magnets reaches 22km and the configuration therefore requires an additional chromaticity correction scheme similar to a dipole first layout option. However, at the same time, the presented solution provides an interesting alternative to a high gradient triplet layout which requires the new Nb3Sn magnet technology.
ADVANCES IN MATCHING WITH MAD-X
A new algorithm and mode has been developed for the matching in MAD-X [1]. The new algorithm, called JACOBIAN, is able to solve a generalized matching problem with an arbitrary number of variables and constraints. It aims at solving the corresponding least square problem. The new mode, called USE MACRO, allows the user to construct his own macros and expressions for the definition of the constraints in a matching problem. The new algorithm combined with the macro constructs was successfully used for finding optic transitions and a non-linear chromaticity correction. This new approach can be seen as a major upgrade of the matching capabilities of MAD-X taking advantage of various modules like twiss, ptc, track, survey, aperture, etc.
A slowly rotating coil system for AC field measurements of Fermilab Booster correctors
A method for measurement of rapidly changing magnetic fields has been developed and applied to the testing of new room temperature corrector packages designed for the Fermilab Booster Synchrotron. The method is based on fast digitization of a slowly rotating tangential coil probe, with analysis combining the measured coil voltages across a set of successive magnet current cycles. This paper presents results on the field quality measured for the normal and skew dipole, quadrupole, and sextupole elements in several of these corrector packages.