111257994
RF Perturbation Measurements in Long Linac Cavities
Equipment and procedures have been developed for measuring the axial accelerating electric field in proton linear accelerator cavities. The method used is the usual one of measuring the change in resonant frequency caused by a small perturbing sphere on the axis of the cavity. The frequency change is determined at millimeter intervals along the axis by measuring the corresponding period length using an on-line digital computer. The computation is carried out on the computer so that the derived fields can be obtained, integrated, plotted, and compared. The method is rapid and the increased precision of the measurement allows better knowledge of the fields in operating linear accelerators. This equipment has been used on the 50-MeV linac injector for the Zero Gradient Synchrotron at Argonne National Laboratory.1 It has also been used to measure the axial field in a cavity with fields which can be calculated using a field computational program.2 The measured and calculated field values have been compared.
55868408
400-MeV upgrade for the Fermilab linac
Fermilab plans to upgrade the Tevatron to expand the physics research program in both the fixed target and the collider operating modes. The first phase of this program is to increase the energy of the H{sup -} linac from 200 to 400 MeV in order to reduce the incoherent space change tuneshift at injection into the Booster which can limit either the brightness or the total intensity of the beam. The linac upgrade will be achieved by replacing the last four 201 MeV, with seven 805 MHz side-coupled cavity modules operating at an average axial field of about 8 MV/m. This will allow acceleration to 400 MeV in the existing Linac enclosure. 4 refs., 3 figs., 1 tab.
111257994
RF Perturbation Measurements in Long Linac Cavities
Equipment and procedures have been developed for measuring the axial accelerating electric field in proton linear accelerator cavities. The method used is the usual one of measuring the change in resonant frequency caused by a small perturbing sphere on the axis of the cavity. The frequency change is determined at millimeter intervals along the axis by measuring the corresponding period length using an on-line digital computer. The computation is carried out on the computer so that the derived fields can be obtained, integrated, plotted, and compared. The method is rapid and the increased precision of the measurement allows better knowledge of the fields in operating linear accelerators. This equipment has been used on the 50-MeV linac injector for the Zero Gradient Synchrotron at Argonne National Laboratory.1 It has also been used to measure the axial field in a cavity with fields which can be calculated using a field computational program.2 The measured and calculated field values have been compared.
117804340
DESIGN OF PROTON LINEAR ACCELERATORS FOR ENERGIES UP TO 300 Mev
Extension of the conventional 2 pi structure for particle acceleration to 200 Mev or higher requires minimization of power losses by optimizing cavity and drift-tube parameters. Using a previously developed method, an optimization of the cavity drift-tube dimensions was made at 200 Mc and at energies of 50, 100, 150, and 200 Mev to give minimum power losses for cylindrical tubes. Drift tubes of other shapes may reduce observed high-energy power losses due to currents in the drift-tube surface. Ellipsoidal tubes appear more efficient than the cylindrical tubes. (D.C.W.)
124960127
THE OPERATION OF THE FIRST SECTION OF THE NAL LINEAR ACCELERATOR.
115467134
OPERATION OF NAL LINAC AT ENERGIES TO 139 MeV.
14018969
Supersymmetric Wilson loops in diverse dimensions
We consider supersymmetric Wilson loopsla Zarembo in planar supersym- metric Yang-Mills theories in diverse dimensions. Using perturbation theory we show that these loops have trivial vacuum expectation values to second order in the 't Hooft coupling. We review the known superspace results which, for specific dimensions, extend this triviality to all orders in the 't Hooft coupling. Using the gauge/gravity correspondence, we construct the explicit dual fun- damental string solutions corresponding to these Wilson loops for the case of circular geometry. We find that the regularized action of these string solutions vanishes. We also generalize the framework of calibrated surfaces to prove the vanishing of the regularized action for loops of general geometry. We propose a possible string-side manifestation of the gauge theory generalized Konishi anomaly in seven dimensions.
199476454
Wilson Loops in N = 2 Superconformal Yang-Mills Theory
48341289
Holographic dual of the Eguchi-Kawai mechanism
A bstractThe holographic dual of $ \mathcal{N} $ = 2*, D = 4 supersymmetric Yang-Mills theory has many features common to 5d CFT. We interpret this as a manifestation of Eguchi-Kawai mechanism.
6991151
Wavy Wilson line and AdS / CFT
Wilson loops which are small deviations from straight, infinite lines, called wavy lines, are considered in the context of the AdS/CFT correspondence. A single wavy line and the connected correlation function of a straight and wavy line are considered. It is argued that, to leading order in "waviness," the functional form of the loop is universal and the coefficient, which is a function of the 't Hooft coupling, is found in weak coupling perturbation theory and the strong coupling limit using the AdS/CFT correspondence. Supersymmetric arguments are used to simplify the computation and to show that the straight line obeys the Migdal–Makeenko loop equation.
55184082
Chiral primary one-point functions in the D3-D7 defect conformal field theory
A bstractWe compute the one-point functions of chiral primary operators in the non-supersymmetric defect conformal field theory that is dual to the IIB string theory on AdS5 × S5 background with a probe D7 brane with internal gauge field flux, both in perturbative Yang-Mills theory and in the string theory dual. The former is expected to be accurate at weak coupling whereas the latter should be accurate in the planar strong coupling limit of the gauge theory. We consider the distinct cases where the D7 brane has geometry AdS4 × S4 with an instanton bundle of the worldvolume gauge fields on S4 and AdS4 × S2 × S2 with Dirac monopole bundles on each S2. The gauge theory computation and the string theory computation can be compared directly in the planar limit and then a subsequent limit where the worldvolume flux is large. We find that there is exact agreement between the two in the leading order.