PAC09 - List of Authors (Hershcovitch, A.)

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Hershcovitch, A.

Paper	Title	Page
MO6RFP001	Enhancing RHIC Luminosity Capabilities with In-situ Beam Pipe Coating	345
	A. Hershcovitch, M. Blaskiewicz, W. Fischer BNL, Upton, Long Island, New York H.J. Poole PVI, Oxnard
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Electron clouds have been observed in many accelerators, including RHIC at BNL. They can limit the machine performance through pressure degradation, beam instabilities or incoherent emittance growth. The formation of electron clouds can be suppressed with beam pipe surfaces that have low secondary electron yield. Also, high wall resistivity in accelerators can result in unacceptably high ohmic heating levels for superconducting magnets. These are concerns RHIC, as its vacuum chamber in the superconducting dipoles is made from relatively high resistivity 316LN stainless steel. The high resistivity can be addressed with a copper (Cu) coating; a reduction in the secondary electron yield can be achieved with a titanium nitride (TiN) or amorphous carbon (a-C) coating. Applying such coatings in an already constructed machine is rather challenging. We sta rted developing a robotic plasma deposition technique for in-situ coating of long, small diameter tubes. The technique entails fabricating a device comprising of staged magnetrons and/or cathodic arcs mounted on a mobile mole for deposition of about 5 μm (a few skin depths) of Cu followed by about 0.1 μm of TiN (or a-C).

Paper

Title

Page

MO6RFP001

Enhancing RHIC Luminosity Capabilities with In-situ Beam Pipe Coating

345

A. Hershcovitch, M. Blaskiewicz, W. Fischer
BNL, Upton, Long Island, New York
H.J. Poole
PVI, Oxnard

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.

Electron clouds have been observed in many accelerators, including RHIC at BNL. They can limit the machine performance through pressure degradation, beam instabilities or incoherent emittance growth. The formation of electron clouds can be suppressed with beam pipe surfaces that have low secondary electron yield. Also, high wall resistivity in accelerators can result in unacceptably high ohmic heating levels for superconducting magnets. These are concerns RHIC, as its vacuum chamber in the superconducting dipoles is made from relatively high resistivity 316LN stainless steel. The high resistivity can be addressed with a copper (Cu) coating; a reduction in the secondary electron yield can be achieved with a titanium nitride (TiN) or amorphous carbon (a-C) coating. Applying such coatings in an already constructed machine is rather challenging. We sta rted developing a robotic plasma deposition technique for in-situ coating of long, small diameter tubes. The technique entails fabricating a device comprising of staged magnetrons and/or cathodic arcs mounted on a mobile mole for deposition of about 5 μm (a few skin depths) of Cu followed by about 0.1 μm of TiN (or a-C).