Optics-measurement-based Beam Position Monitor calibration

Abstract

Accurate measurements of the focusing properties of an accelerator are essential for properoperation of a synchrotron, both for the machine protection and for the performance of the experiment. Measurement of linear optics functions based on turn-by-turn measurements has been developed continuously in pursuit of more accurate results [1, 2, 3, 4]. Optics functions that describe the focusing properties of the machine can be obtained from different observables: phase and amplitude of the transverse betatron oscillations and the change of the tune by modulating the current of quadrupoles (K-modulation) [5]. Reconstruction of linear optics using the phase, in combination with K-modulation, have been the main approaches for obtaining the function in accelerators all over the world [3, 6, 7]. Measurements of optics functions based on the amplitude [8], denoted as from amplitude, have not been used as widely as the other methods since it requires accurate beam-position-monitor (BPM) calibration...

Poder medir de forma precisa las propiedades de enfoque de un acelarador es extremadamente importante para una adecuada operacion del sincrotron, tanto desde el punto de vista de proteccion de los componentes del acelerador como desde el punto de vista del rendimiento delos experimentos [1, 2, 3, 4]. Las funciones opticas, que describen las propiedades de enfoque del acelerador, se puedenobtener mediante distintos observables: fase y amplitud de las oscilaciones betatronicas que realiza el haz en el plano transversal, o mediante la medida del tono mediante la modulacion dela corriente en los cuadrupolos (K-modulation) [5]. En concreto, la reconstruccion de la parte linear de la optica del acelerador se ha basado durante los ultimos a~nos en las medidas de fase yK-modulation...