CERN Accelerating science

Internal Note
Report number	LHC-PROJECT-NOTE-320
Title	The Aperture and Layout of the LHC Extraction Septa and TCDS Diluter with an Enlarged MSDC Vacuum Chamber
Author(s)	Goddard, B (CERN) ; Gyr, Marcel (CERN)
Submitted by	[email protected] on 13 Aug 2003
Subject category	Accelerators and Storage Rings
Accelerator/Facility, Experiment	CERN LHC
Free keywords	Beam Dumping System, Extraction Septum, Aperture
Abstract	The LHC beam dumping system must safely abort the LHC beams over the whole energy range, under all realistically possible fault conditions. These include normal operation, failure of machine elements and also abnormal performance of subsystems of the beam dumping system itself. To avoid unnecessary irradiation and even equipment damage, the MSD extraction septa must provide sufficient aperture both for the circulating and extracted beams. In order to satisfy this requirement, a modified (enlarged) vacuum chamber design will be used for the limiting MSDC septa. The analysis of the available apertures is presented, with emphasis on the dependence on the local orbit and beam emittance.