PAC2013 - List of Authors (Hulsart, R.L.)

Paper	Title	Page
TUPBA08	Measurement of Beam Optics During Acceleration in the Relativistic Heavy Ion Collider	538
	M.G. Minty, K.A. Drees, R.L. Hulsart, C. Liu, A. Marusic, R.J. Michnoff, P. Thieberger BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. We describe a new and minimally invasive method for near real-time measurement of the evolution of critical beam optical parameters during acceleration of beams to high energies in the Relativistic Heavy Ion Collider (RHIC) at BNL. The implementation uses existing hardware to periodically excite a single bunch in the beam and leverages off of improved precision and deterministic data delivery from the RHIC beam position monitors operating in turn-by-turn mode. The beam response to the external excitations was observed to decohere on a relatively short time scale so allowing near-simultaneous data acquisition in the horizontal and vertical planes. The excitations and acquisitions are carefully timed to allow coexistence with normal ramp orbit feedback operating at a 1 Hz rate. Respecting the limitations of the data transfer times, important parameters such as the beta functions, local phase advance, and betatron tune spread were measured in both accelerators and both transverse planes at a maximum rate of once every 2 seconds / 4 seconds in each of the two RHIC accelerators respectively. The measurement architecture is described together with select experimental results.

Paper

Title

Page

Measurement of Beam Optics During Acceleration in the Relativistic Heavy Ion Collider

538

M.G. Minty, K.A. Drees, R.L. Hulsart, C. Liu, A. Marusic, R.J. Michnoff, P. Thieberger
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
We describe a new and minimally invasive method for near real-time measurement of the evolution of critical beam optical parameters during acceleration of beams to high energies in the Relativistic Heavy Ion Collider (RHIC) at BNL. The implementation uses existing hardware to periodically excite a single bunch in the beam and leverages off of improved precision and deterministic data delivery from the RHIC beam position monitors operating in turn-by-turn mode. The beam response to the external excitations was observed to decohere on a relatively short time scale so allowing near-simultaneous data acquisition in the horizontal and vertical planes. The excitations and acquisitions are carefully timed to allow coexistence with normal ramp orbit feedback operating at a 1 Hz rate. Respecting the limitations of the data transfer times, important parameters such as the beta functions, local phase advance, and betatron tune spread were measured in both accelerators and both transverse planes at a maximum rate of once every 2 seconds / 4 seconds in each of the two RHIC accelerators respectively. The measurement architecture is described together with select experimental results.