Accelerator Beam Position Monitors using Rogowski coil

Author: Dito Shergelashvili
Keywords: accelerators, beam position, Rogowski coil
Annotation:

Among the most fascinating miracles of Nature stands the puzzle of our existence – from the scientific point of view. In the Big Bang, matter and antimatter have been produced from energy in equal amount. When matter and antimatter meet they annihilate into photons, which in principle again can produce matter-antimatter particle-pairs: the question of why there is only matter and almost no antimatter found in our Universe remains unanswered. During the evolution of the very early universe, a tiny asymmetry – approximately 1 part in a billion appeared at some point, and after the annihilation process, the totality of the one left-over particle constitutes the matter of our world. There must be a difference between matter and antimatter (particles and antiparticles), which has actually been observed in decays of some elementary particles. This difference is due to a symmetry breaking and is referred as CP-violation. Permanent electric dipole moments (EDM) of elementary particles (the spatial separation of the center-of-gravity of the positive and negative charge distributions) violate parity (P) and time reversal (T) symmetry, and thus – via CPT – also CP. CP-violation is one of the ingredients (Sakharov conditions) required to explain the matter-antimatter asymmetry in our universe. If an EDM were to be found, it would indicate a new and additional CPV source. The new idea, promoted at Jülich, to search for EDMs of charged particles (protons, deuterons) in novel precision storage rings (srEDM) will exploit stored polarized beams and observe a miniscule rotation of the polarization axis as a function of time due to the interaction of a finite EDM with large electric fields. Key challenge for srEDM is the provision of a sensitive and efficient method to determine the tiny change of the beam polarization direction. A new class of precision storage rings is required to search for electric dipole moments (EDMs) of charged particles with unprecedented sensitivity. It is the aim of the JEDI project to take a decisive step towards the design and construction of such a facility by establishing the required key technologies and to deliver the first-measured EDMs for the deuteron using the existing cooler storage ring COSY. This paper discusses high resolution new beam position monitors for novel storage ring COSY. It contains theoretical analysis of new signal pick up system based on Rogowski coil and experiments on first prototype using the test bench.