There are close similarities between SLD (1992-1998) and FCC-ee(TeraZ) which will possibly be operating from 2045. While the collider technology will switch from linear to circular, both machines operate at the Z pole and produce a similar luminosity per bunch crossing, but with a factor ~10^6 higher luminosity due mainly to the increased bunch crossing frequency (120 Hz to 50 MHz). What was overlooked in the FCC Feasibility Study was the consequential increase in background, of which there are at least two types, which could disable all 4 vertex detectors. In this talk, we review the lessons from SLD, and present ideas for handling these backgrounds at FCC-ee.
Biography: Chris Damerell grew up in Cape Town, attended UCT, then joined Oxford University as a graduate student in 1962, joyfully supervised for his D Phil by Bill Williams and Arthur Clegg. His thesis experiment (one of the first on Nimrod) was pi-minus p charge exchange scattering with spark chambers. He then worked as a postdoctoral researcher at Brookhaven Lab in the Cornell-Brookhaven group, led by Jay Orear, which discovered backward peaks in meson-baryon scattering. This was followed from 1967 at Rutherford High Energy Lab (as it then was), attached to the Birmingham Group led by John Dowell, studying K-p elastic scattering, back on Nimrod. Then, to CERN working with Arne Lundby on hypercharge exchange processes on the PS, followed by one of the first SPS experiments (WA3), production of heavy meson resonances in the CERN-Munich Group, which became ACCMOR (Amsterdam, CERN, Cracow, Munich, Oxford, Rutherford). During this time (after the November Revolution of November 1974), the collaboration turned to the search for hadronic production of charm, at a higher energy beam in the North Area (NA11 then NA32). This involved half a dozen techniques, of which the most successful was the first use of CCDs for particle tracking, pixel detectors which delivered point measurement precision of less than 5 microns, by the UK groups.
In 1981, this technique caught the attention of the SLD Collaboration at SLAC, led by Marty Breidenbach, which provided millions of dollars of support for R&D to extend these devices from postage-stamp size, to cover 3 long barrels of stitched CCDs for a vertex detector of 307 Mpixels, which operated perfectly from 1992 till the completion of SLD running in 1998.
The RAL group has continued to contribute to the development of vertex detectors for e+e- colliders at the energy frontier (linear or circular, currently under study for FCC-ee), despite the decision of STFC to ‘cease investment’ in this area of research since 2008.