IPAC2011 - List of Authors (Commisso, M.)

Paper	Title	Page
TUPS009	SEY of Al Samples from the Dipole Chamber of PETRA III at DESY	1533
	D. R. Grosso, R. Cimino, M. Commisso INFN/LNF, Frascati (Roma), Italy R. Flammini CNR-IMIP, Monterotondo Stazione RM, Italy R. Larciprete ISM-CNR, Rome, Italy R. Wanzenberg DESY, Hamburg, Germany
	At the synchrotron radiation facility PETRA III, tune spectra have been measured with some characteristics which are typically observed at other storage rings in connection with electron cloud effects. For some bunch filling patterns, an increase of the vertical emittance has been observed. To estimate such effects with the available e-cloud simulation codes, the detailed knowledge of the SEY (Secondary Electron Yield) of the Al chamber, is required. To the purpose, representative PETRA III Al samples, were studied in detail at the INFN-LNF Surface Science Laboratory. XPS (X-ray photoelectron spectroscopy) and SEY measurements were performed as a function of electron and argon ion conditioning. The SEY of the as received samples shows a maximum value of δmax ≅ 2.8. Electron conditioning at 500 eV kinetic energy, reduces the SEY to values between δmax ≅ 1.8 to 1.4 (depending on the actual sample analyzed). The XPS characterization of the sample surface, after several cycles of argon ion sputtering, shows clearly that the SEY variation is closely related to the oxidation state of the Al sample, reaching a δmax value as low as 1.3 for our cleanest surface.

THPC159	Factory Acceptance Test of COLDDIAG: A Cold Vacuum Chamber for Diagnostics	3263
	S. Gerstl, T. Baumbach, S. Casalbuoni, A.W. Grau, M. Hagelstein, T. Holubek, D. Saez de Jauregui Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany V. Baglin CERN, Geneva, Switzerland C. Boffo, G. Sikler BNG, Würzburg, Germany T.W. Bradshaw STFC/RAL, Chilton, Didcot, Oxon, United Kingdom R. Cimino, M. Commisso, A. Mostacci, B. Spataro INFN/LNF, Frascati (Roma), Italy J.A. Clarke, R.M. Jones, D.J. Scott Cockcroft Institute, Warrington, Cheshire, United Kingdom M.P. Cox, J.C. Schouten Diamond, Oxfordshire, United Kingdom I.R.R. Shinton UMAN, Manchester, United Kingdom E.J. Wallén MAX-lab, Lund, Sweden R. Weigel Max-Planck Institute for Metal Research, Stuttgart, Germany
	Superconductive insertion devices (IDs) have higher fields for a given gap and period length compared with the state-of-the-art technology of permanent magnet IDs. One of the still open issues for the development of superconductive insertion devices is the understanding of the heat intake from the electron beam. With the aim of measuring the beam heat load to a cold bore and the hope to gain a deeper understanding in the underlying mechanisms, a cold vacuum chamber for diagnostics was built. It is equipped with the following instrumentation: retarding field analyzers to measure the electron flux, temperature sensors to measure the beam heat load, pressure gauges, and mass spectrometers to measure the gas content. The flexibility of the engineering design will allow the installation of the cryostat in different synchrotron light sources. The installation in the storage ring of the Diamond Light Source is foreseen in November 2011. Here we report about the technical design of this device, the factory acceptance test and the planned measurements with electron beam.

Paper

Title

Page

SEY of Al Samples from the Dipole Chamber of PETRA III at DESY

1533

D. R. Grosso, R. Cimino, M. Commisso
INFN/LNF, Frascati (Roma), Italy
R. Flammini
CNR-IMIP, Monterotondo Stazione RM, Italy
R. Larciprete
ISM-CNR, Rome, Italy
R. Wanzenberg
DESY, Hamburg, Germany

At the synchrotron radiation facility PETRA III, tune spectra have been measured with some characteristics which are typically observed at other storage rings in connection with electron cloud effects. For some bunch filling patterns, an increase of the vertical emittance has been observed. To estimate such effects with the available e-cloud simulation codes, the detailed knowledge of the SEY (Secondary Electron Yield) of the Al chamber, is required. To the purpose, representative PETRA III Al samples, were studied in detail at the INFN-LNF Surface Science Laboratory. XPS (X-ray photoelectron spectroscopy) and SEY measurements were performed as a function of electron and argon ion conditioning. The SEY of the as received samples shows a maximum value of δmax ≅ 2.8. Electron conditioning at 500 eV kinetic energy, reduces the SEY to values between δmax ≅ 1.8 to 1.4 (depending on the actual sample analyzed). The XPS characterization of the sample surface, after several cycles of argon ion sputtering, shows clearly that the SEY variation is closely related to the oxidation state of the Al sample, reaching a δmax value as low as 1.3 for our cleanest surface.

THPC159

Factory Acceptance Test of COLDDIAG: A Cold Vacuum Chamber for Diagnostics

3263

S. Gerstl, T. Baumbach, S. Casalbuoni, A.W. Grau, M. Hagelstein, T. Holubek, D. Saez de Jauregui
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
V. Baglin
CERN, Geneva, Switzerland
C. Boffo, G. Sikler
BNG, Würzburg, Germany
T.W. Bradshaw
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
R. Cimino, M. Commisso, A. Mostacci, B. Spataro
INFN/LNF, Frascati (Roma), Italy
J.A. Clarke, R.M. Jones, D.J. Scott
Cockcroft Institute, Warrington, Cheshire, United Kingdom
M.P. Cox, J.C. Schouten
Diamond, Oxfordshire, United Kingdom
I.R.R. Shinton
UMAN, Manchester, United Kingdom
E.J. Wallén
MAX-lab, Lund, Sweden
R. Weigel
Max-Planck Institute for Metal Research, Stuttgart, Germany

Superconductive insertion devices (IDs) have higher fields for a given gap and period length compared with the state-of-the-art technology of permanent magnet IDs. One of the still open issues for the development of superconductive insertion devices is the understanding of the heat intake from the electron beam. With the aim of measuring the beam heat load to a cold bore and the hope to gain a deeper understanding in the underlying mechanisms, a cold vacuum chamber for diagnostics was built. It is equipped with the following instrumentation: retarding field analyzers to measure the electron flux, temperature sensors to measure the beam heat load, pressure gauges, and mass spectrometers to measure the gas content. The flexibility of the engineering design will allow the installation of the cryostat in different synchrotron light sources. The installation in the storage ring of the Diamond Light Source is foreseen in November 2011. Here we report about the technical design of this device, the factory acceptance test and the planned measurements with electron beam.