0000000000909332
AUTHOR
J. Bernard
Electron and positron cooling of highly charged ions in a cooler Penning trap
Abstract Electron cooling is a well-established technique to increase the phase space density of particle beams in storage rings. In this paper, we discuss the feasibility of electron and positron cooling of ions in a Penning trap. We calculate the cooling times for the cases of trapped bare ions with nuclear charge Z =1 (protons), Z =36 (krypton) and Z =92 (uranium) with the Spitzer formula. Our calculations show that for typical experimental conditions the time for cooling from initial energies of 10 keV per charge down to rest is in the order of a second. We investigate the dependence of the cooling time on the number of ions and electrons, and their charge and mass.
The European Photon Imaging Camera on XMM-Newton: The MOS Cameras
The EPIC focal plane imaging spectrometers on XMM-Newton use CCDs to record the images and spectra of celestial X-ray sources focused by the three X-ray mirrors. There is one camera at the focus of each mirror; two of the cameras contain seven MOS CCDs, while the third uses twelve PN CCDs, defining a circular field of view of 30 arcmin diameter in each case. The CCDs were specially developed for EPIC, and combine high quality imaging with spectral resolution close to the Fano limit. A filter wheel carrying three kinds of X-ray transparent light blocking filter, a fully closed, and a fully open position, is fitted to each EPIC instrument. The CCDs are cooled passively and are under full clos…