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Parameters are being studied for a high luminosity e+e-collider operating at the Upsilon 4S that would deliver a luminosity of over 1036/ cm2/s. This collider, called a Super-B Factory, would use a novel combination of linear collider and storage ring techniques. In this scheme an electron beam and a positron beam are stored in low-emittance damping rings similar to those designed for a Linear Collider (LC). A LC style interaction region is included in the ring to produce sub-millimeter vertical beta functions at the collision point. A large crossing angle (+/- 17 mrad) is used at the collision point to allow beam separation and reduce the hourglass effects. Beam currents of about 2.3 A x 1.3 A at 4 x 7 GeV in 1733 bunches can produce a luminosity of 1036/cm2/s. Such a collider would produce an integrated luminosity of about 10,000 fb-1 (10 ab-1) in a running year (10s 7 sec) at the Y(4S) resonance. ©2007 IEEE.

The Next and Global Linear Collider (NLC/GLC) designs require precision alignment of the beam in the accelerator structures to reduce short range wakefields. The moderately damped and detuned structures themselves provide suitable higher order mode (HOM) signals to measure this alignment. The modes in the lowest dipole band, whose frequencies range from 14-16 GHz, provide the strongest signals. To determine the position resolution they provide, an NLC/GLC prototype structure that was installed in the ASSET facility of the SLAC Linac was instrumented to downmix and digitize these signals. The beam position within the structure was determined by simultaneously measuring the signals at three frequencies (14.3, 15, 15.7 GHz) corresponding to modes localized at the beginning, the middle and the end of the 60 cm long structure. A resolution of 1 micron was achieved even with 28 dB signal attenuation, which is better than the 5 micron resolution required for the NLC/GLC.

Fermilab and other DOE high energy physics laboratories are studying the possibility of a Very Large Hadron Collider (VLHC) for operation in the post-LHC era. The current VLHC design foresees a 2-staged approach, where the second stage (referred to as VLHC-2) has a proton energy up to 100 TeV at a peak luminosity of 2/sup ./10/sup 34/ cm/sup -2/ sec/sup -1/. The protons are guided through a large 233 km circumference ring with 10 T bending magnets using Nb/sub 3/Sn superconductor at 5 K. The synchrotron radiation (SR) power emitted by the beam in such a machine is /spl sim/5 W/m/beam. However, other VLHC scenarios with smaller rings and higher luminosity result in SR power levels exceeding this value, reaching 10 or even 20 W/m/beam. Intercepting and removing this power in a cryogenic environment is a major challenge. In this paper a discussion of SR in the VLHC-2, and various approaches to the issue, are presented.