Extraction for ISABELLE

The design specifications for ISABELLE, a superconducting proton storage ring facility under construction at Brookhaven National Laboratory call for circulating beam intensities of up to 6 x 1014 protons at 400 GeV energy in each ring. The energy stored in the beam is 41 Megajoules, an order of magnitude more than what has been dealt with in the past. This beam energy cannot be safely disposed of within the confines of the ISABELLE lattice if damage to the dump or quenching of the superconducting magnets is to be avoided. Therefore the full intensity beam must be extracted from the storage rings under all circumstances of emergency or routine beam disposal. Beam losses in excess of 10-3 of the full beam can jeopardize the extraction components and lead to magnet quenching as well. In this note we summarize a conceptual design of the extraction system and discuss the major constraints which lead to the parameters chosen.