DIPAC2011 - List of Authors (Gasior, M.)

Paper

Title

Page

Electromagnetic Simulations of an Embedded BPM in Collimator Jaws

71

A.A. Nosych, C.B. Boccard, M. Gasior
CERN, Geneva, Switzerland

Next generation of the LHC collimators will be equipped with button beam position monitors (BPMs) embedded into the collimator jaws. Such a solution will improve the accuracy of the jaw alignment with respect to the beam and reduce the beam time necessary for the collimator setup. This paper describes results of electromagnetic simulations of the jaw BPMs performed with the CST Particle Studio suite, aimed at characterisation of the BPMs as well as the simulation software itself. The results are compared to the measurements obtained with beam on a prototype system installed in the CERN SPS.

Poster MOPD15 [6.439 MB]

MOPD18

Embedded Collimator Beam Position Monitors

80

C.B. Boccard, A. Bertarelli, A. Dallocchio, M. Gasior, L. Gentini, A.A. Nosych
CERN, Geneva, Switzerland

The LHC collimation system is crucial for safe and reliable operation of proton beams with 350 MJ stored energy. Currently the collimator set-up is performed by observing beam losses when approaching the collimator jaws to the beam. For all 100 LHC movable collimators the procedure may take several hours and since it has to be repeated whenever the beam configuration changes significantly, the collimator setup has an important impact on the overall machine operation efficiency. To reduce the collimator setup time by two orders of magnitude the next generation of the LHC collimators will be equipped with button beam position monitors (BPMs) embedded into the collimator jaws. This paper describes the BPM design and presents prototype results obtained with beam in the CERN-SPS.

Poster MOPD18 [1.729 MB]

MOPD24

A High-resolution Diode-based Orbit Measurement System – Prototype Results from the LHC

98

M. Gasior, J. Olexa, R.J. Steinhagen
CERN, Geneva, Switzerland

The prototype of a high resolution beam position monitor (BPM) electronics based on diode peak detectors was tested with LHC beams. In this technique developed at CERN the short beam pulses from each BPM electrode are converted into slowly varying signals by compensated diode peak detectors. The slow signals can be digitised with a laboratory voltmeter or high resolution ADC. As presented in the paper, this technique allows resolutions in the order of 1 ppm of the BPM aperture to be achieved with a measurement rate in the Hz range. Ongoing developments and future prospects for the technique are also discussed.

Poster MOPD24 [2.055 MB]

MOPD87

The LHC Beam Presence Flag System

251

M. Gasior, T.B. Bogey
CERN, Geneva, Switzerland

Before injecting any high intensity bunches into the LHC a circulating low intensity pilot bunch must be present to confirm the correct settings of the main machine parameters. For the 2010 LHC run the detection of this pilot beam was done with the beam current transformer system. To increase redundancy of this important safety function a dedicated beam presence flag system was designed, built and tested with beam to be used operationally in the 2011 run. In this system signals from four electrodes of a beam position monitor (BPM) are processed with separate channels, resulting in a quadruple system redundancy for either beam. Each system channel consists of an analogue front-end converting the BPM signals into two logic states, which are then transmitted optically to the machine protection and interlock systems. For safety reasons the system does not have any remote control or adjustable elements and its only inputs are the beam signals. This paper describes the new LHC beam presence flag system, in particular the analogue front-end based on diode peak detectors.

Poster MOPD87 [8.200 MB]

TUPD72

Advancements in the Base-Band-Tune and Chromaticity Instrumentation and Diagnostics Systems during LHC's First Year of Operation

476

R.J. Steinhagen, M. Gasior, S. Jackson
CERN, Geneva, Switzerland

The Base-Band-Tune (BBQ) system is an integral part of day-to-day LHC operation, used for tune and chromaticity diagnostics and feedback and giving unprecedented precision with good reliability. This contribution summarises the system's overall performance and documents the various improvements of the analogue front-end circuitry, digital post-processing and integration that were necessary in response to issues arising during high-intensity physics operation. The result of beam studies undertaken are presented, which have established a better understanding of the detection principle since its first introduction in 2005.

Poster TUPD72 [0.794 MB]

Paper	Title	Page
MOPD15	Electromagnetic Simulations of an Embedded BPM in Collimator Jaws	71
	A.A. Nosych, C.B. Boccard, M. Gasior CERN, Geneva, Switzerland
	Next generation of the LHC collimators will be equipped with button beam position monitors (BPMs) embedded into the collimator jaws. Such a solution will improve the accuracy of the jaw alignment with respect to the beam and reduce the beam time necessary for the collimator setup. This paper describes results of electromagnetic simulations of the jaw BPMs performed with the CST Particle Studio suite, aimed at characterisation of the BPMs as well as the simulation software itself. The results are compared to the measurements obtained with beam on a prototype system installed in the CERN SPS.
	Poster MOPD15 [6.439 MB]

MOPD18	Embedded Collimator Beam Position Monitors	80
	C.B. Boccard, A. Bertarelli, A. Dallocchio, M. Gasior, L. Gentini, A.A. Nosych CERN, Geneva, Switzerland
	The LHC collimation system is crucial for safe and reliable operation of proton beams with 350 MJ stored energy. Currently the collimator set-up is performed by observing beam losses when approaching the collimator jaws to the beam. For all 100 LHC movable collimators the procedure may take several hours and since it has to be repeated whenever the beam configuration changes significantly, the collimator setup has an important impact on the overall machine operation efficiency. To reduce the collimator setup time by two orders of magnitude the next generation of the LHC collimators will be equipped with button beam position monitors (BPMs) embedded into the collimator jaws. This paper describes the BPM design and presents prototype results obtained with beam in the CERN-SPS.
	Poster MOPD18 [1.729 MB]

MOPD24	A High-resolution Diode-based Orbit Measurement System – Prototype Results from the LHC	98
	M. Gasior, J. Olexa, R.J. Steinhagen CERN, Geneva, Switzerland
	The prototype of a high resolution beam position monitor (BPM) electronics based on diode peak detectors was tested with LHC beams. In this technique developed at CERN the short beam pulses from each BPM electrode are converted into slowly varying signals by compensated diode peak detectors. The slow signals can be digitised with a laboratory voltmeter or high resolution ADC. As presented in the paper, this technique allows resolutions in the order of 1 ppm of the BPM aperture to be achieved with a measurement rate in the Hz range. Ongoing developments and future prospects for the technique are also discussed.
	Poster MOPD24 [2.055 MB]

MOPD87	The LHC Beam Presence Flag System	251
	M. Gasior, T.B. Bogey CERN, Geneva, Switzerland
	Before injecting any high intensity bunches into the LHC a circulating low intensity pilot bunch must be present to confirm the correct settings of the main machine parameters. For the 2010 LHC run the detection of this pilot beam was done with the beam current transformer system. To increase redundancy of this important safety function a dedicated beam presence flag system was designed, built and tested with beam to be used operationally in the 2011 run. In this system signals from four electrodes of a beam position monitor (BPM) are processed with separate channels, resulting in a quadruple system redundancy for either beam. Each system channel consists of an analogue front-end converting the BPM signals into two logic states, which are then transmitted optically to the machine protection and interlock systems. For safety reasons the system does not have any remote control or adjustable elements and its only inputs are the beam signals. This paper describes the new LHC beam presence flag system, in particular the analogue front-end based on diode peak detectors.
	Poster MOPD87 [8.200 MB]

TUPD72	Advancements in the Base-Band-Tune and Chromaticity Instrumentation and Diagnostics Systems during LHC's First Year of Operation	476
	R.J. Steinhagen, M. Gasior, S. Jackson CERN, Geneva, Switzerland
	The Base-Band-Tune (BBQ) system is an integral part of day-to-day LHC operation, used for tune and chromaticity diagnostics and feedback and giving unprecedented precision with good reliability. This contribution summarises the system's overall performance and documents the various improvements of the analogue front-end circuitry, digital post-processing and integration that were necessary in response to issues arising during high-intensity physics operation. The result of beam studies undertaken are presented, which have established a better understanding of the detection principle since its first introduction in 2005.
	Poster TUPD72 [0.794 MB]