IBIC2014 - List of Authors (Dehning, B.)

Paper	Title	Page
MOPF16	CERN-SPS Wire Scanner Impedence and Wire Heating Studies	88
	E. Piselli, O.E. Berrig, F. Caspers, B. Dehning, J. Emery, M. Hamani, J. Kuczerowski, B. Salvant, R.S. Sautier, R. Veness, C. Vuitton, C. Zannini CERN, Geneva, Switzerland
	This article describes a study performed on one of the SPS vertical rotational wire scanners in order to investigate the breakage of the wire, which occurred on several occasions during the last year of operation. The thermionic emission current of the wire was measured to evaluate temperature changes, and was observed to rise significantly as the wire approached the ultimate LHC beam in the SPS, indicating the possibility of strong coupling between the beam’s electromagnetic field and the wire. Different laboratory measurements, complemented by CST Microwave Studio simulations, have therefore been performed to try and understand the RF modes responsible for this heating. These results are presented here, along with the subsequent modifications adopted on all of the operational SPS wire scanners.
	Poster MOPF16 [0.747 MB]
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TUPD25	Cryogenic Beam Loss Monitors for the Superconducting Magnets of the LHC	471
	M.R. Bartosik, B. Dehning, M. Sapinski CERN, Geneva, Switzerland V. Eremin, E. Verbitskaya IOFFE, St. Petersburg, Russia E. Griesmayer CIVIDEC Instrumentation, Wien, Austria C. Kurfuerst EBG MedAustron, Wr. Neustadt, Austria
	Funding: This research project has been supported by a Marie Curie Early Initial Training Network Fellowship of the European Community’s Seventh Framework Programme (contract number: PITN-GA-2011-289485-OPAC). The Beam Loss Monitoring (BLM) detectors close to the interaction points (IP) of the Large Hadron Collider (LHC) are currently located outside the cryostat, far from the superconducting coils of the magnets. In addition to their sensitivity to lost beam particles, they also detect particles coming from the experimental collisions, which do not contribute significantly to the heat deposition in the superconducting coils. In the future, with beams of higher energy and brightness resulting in higher luminosity, distinguishing between these interaction products and dangerous quench-provoking beam losses from the primary proton beams will be challenging. The system can be optimised by locating beam loss monitors as close as possible to the superconducting coils, inside the cold mass of the magnets in superfluid helium at 1.9 K. The dose then measured by such Cryogenic Beam Loss Monitors (CryoBLMs) would more precisely correspond to the real dose deposited in the coil. The candidates under investigation for such detectors are based on silicon and diamond, several of which have now been installed inside the magnets in the LHC tunnel. This contribution will present the mechanical and electrical designs of these systems, as well as the results of their qualification testing.
	Poster TUPD25 [7.897 MB]
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Paper

Title

Page

CERN-SPS Wire Scanner Impedence and Wire Heating Studies

88

E. Piselli, O.E. Berrig, F. Caspers, B. Dehning, J. Emery, M. Hamani, J. Kuczerowski, B. Salvant, R.S. Sautier, R. Veness, C. Vuitton, C. Zannini
CERN, Geneva, Switzerland

This article describes a study performed on one of the SPS vertical rotational wire scanners in order to investigate the breakage of the wire, which occurred on several occasions during the last year of operation. The thermionic emission current of the wire was measured to evaluate temperature changes, and was observed to rise significantly as the wire approached the ultimate LHC beam in the SPS, indicating the possibility of strong coupling between the beam’s electromagnetic field and the wire. Different laboratory measurements, complemented by CST Microwave Studio simulations, have therefore been performed to try and understand the RF modes responsible for this heating. These results are presented here, along with the subsequent modifications adopted on all of the operational SPS wire scanners.

Poster MOPF16 [0.747 MB]

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TUPD25

Cryogenic Beam Loss Monitors for the Superconducting Magnets of the LHC

471

M.R. Bartosik, B. Dehning, M. Sapinski
CERN, Geneva, Switzerland
V. Eremin, E. Verbitskaya
IOFFE, St. Petersburg, Russia
E. Griesmayer
CIVIDEC Instrumentation, Wien, Austria
C. Kurfuerst
EBG MedAustron, Wr. Neustadt, Austria

Funding: This research project has been supported by a Marie Curie Early Initial Training Network Fellowship of the European Community’s Seventh Framework Programme (contract number: PITN-GA-2011-289485-OPAC).
The Beam Loss Monitoring (BLM) detectors close to the interaction points (IP) of the Large Hadron Collider (LHC) are currently located outside the cryostat, far from the superconducting coils of the magnets. In addition to their sensitivity to lost beam particles, they also detect particles coming from the experimental collisions, which do not contribute significantly to the heat deposition in the superconducting coils. In the future, with beams of higher energy and brightness resulting in higher luminosity, distinguishing between these interaction products and dangerous quench-provoking beam losses from the primary proton beams will be challenging. The system can be optimised by locating beam loss monitors as close as possible to the superconducting coils, inside the cold mass of the magnets in superfluid helium at 1.9 K. The dose then measured by such Cryogenic Beam Loss Monitors (CryoBLMs) would more precisely correspond to the real dose deposited in the coil. The candidates under investigation for such detectors are based on silicon and diamond, several of which have now been installed inside the magnets in the LHC tunnel. This contribution will present the mechanical and electrical designs of these systems, as well as the results of their qualification testing.

Poster TUPD25 [7.897 MB]

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reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)