IPAC2012 - List of Authors (Wollmann, D.)

Paper	Title	Page
TUPPR097	Modeling and Simulation of LHC Beam-Based Collimator Setup	2059
	G. Valentino, N.J. Sammut University of Malta, Information and Communication Technology, Msida, Malta R.W. Assmann, F. Burkart, S. Redaelli, A. Rossi, D. Wollmann CERN, Geneva, Switzerland L. Lari IFIC, Valencia, Spain
	In the 2011 Large Hadron Collider run, collimators were aligned for proton and heavy ion beams using a semi-automatic setup algorithm. The algorithm provided a reduction in the beam time required for setup, an elimination of beam dumps during setup and higher accuracy with respect to manual alignment. A collimator setup simulator was developed based on a Gaussian model of the beam distribution as well as a parametric model of the beam losses. A time-varying beam loss signal can be simulated for a given collimator movement into the beam. The simulation results and comparison to measurement data obtained during collimator setups and dedicated fills for beam halo scraping are presented. The simulator will then be used to develop a fully automatic collimator alignment algorithm.

THPPR039	Controlled Transverse Blow-Up of High-energy Proton Beams for Aperture Measurements and Loss Maps	4059
	W. Höfle, R.W. Assmann, S. Redaelli, R. Schmidt, D. Valuch, D. Wollmann, M. Zerlauth CERN, Geneva, Switzerland
	A technique was developed to blow-up transversely in a controlled way high energy proton beams in the LHC. The technique is based on band limited white noise excitation that is injected into the transverse damper feedback loop. The injected signal can be gated to selectively blow-up individual trains of bunches. The speed of transverse blow-up can be precisely controlled. This opens the possibility to perform safely and efficiently aperture measurements and loss maps with high intensity bunch trains well above stored beam energies that are considered to be safe. In particular, lengthy procedures for measurements at top energy, otherwise requiring multiple fills of individual bunches, can be avoided. In this paper, the method is presented and results from beam measurements are discussed and compared with alternative blow-up methods.

Paper

Title

Page

Modeling and Simulation of LHC Beam-Based Collimator Setup

2059

G. Valentino, N.J. Sammut
University of Malta, Information and Communication Technology, Msida, Malta
R.W. Assmann, F. Burkart, S. Redaelli, A. Rossi, D. Wollmann
CERN, Geneva, Switzerland
L. Lari
IFIC, Valencia, Spain

In the 2011 Large Hadron Collider run, collimators were aligned for proton and heavy ion beams using a semi-automatic setup algorithm. The algorithm provided a reduction in the beam time required for setup, an elimination of beam dumps during setup and higher accuracy with respect to manual alignment. A collimator setup simulator was developed based on a Gaussian model of the beam distribution as well as a parametric model of the beam losses. A time-varying beam loss signal can be simulated for a given collimator movement into the beam. The simulation results and comparison to measurement data obtained during collimator setups and dedicated fills for beam halo scraping are presented. The simulator will then be used to develop a fully automatic collimator alignment algorithm.

THPPR039

Controlled Transverse Blow-Up of High-energy Proton Beams for Aperture Measurements and Loss Maps

4059

W. Höfle, R.W. Assmann, S. Redaelli, R. Schmidt, D. Valuch, D. Wollmann, M. Zerlauth
CERN, Geneva, Switzerland

A technique was developed to blow-up transversely in a controlled way high energy proton beams in the LHC. The technique is based on band limited white noise excitation that is injected into the transverse damper feedback loop. The injected signal can be gated to selectively blow-up individual trains of bunches. The speed of transverse blow-up can be precisely controlled. This opens the possibility to perform safely and efficiently aperture measurements and loss maps with high intensity bunch trains well above stored beam energies that are considered to be safe. In particular, lengthy procedures for measurements at top energy, otherwise requiring multiple fills of individual bunches, can be avoided. In this paper, the method is presented and results from beam measurements are discussed and compared with alternative blow-up methods.