110416727
Synchronous Transfer of Beam from the NAL Fast Cycling Booster Synchrotron to the NAL Main Ring System
Beam from successive cycles of the 15-Hz booster synchrotron is stacked end to end in the main synchrotron with constant magnetic field. Beam already injected into the main ring is held in stationary rf buckets, and the rest field is determined by the circulating beam. To capture beam from subsequent booster cycles into the empty buckets in the main ring, the phase and frequency of the rf beam bunches in the booster are locked to the main ring rf system before beam is transferred. The magnetic fields in the booster and the main ring are regulated separately and tuned for the correct orbit radii and particle momentum. The azimuth of the beam circulating in the main ring is monitored by counting main ring rf cycles, and the beam transfer system is timed to inject beam from successive booster cycles in the correct sequence around the main-ring circumference.
110477210
Clock Noise Removal in LISA
The relative motion of the LISA spacecraft will Doppler shift the laser frequencies by around 15 MHz. These Doppler shifts introduce sensitivity to the phase noise of the measurement’s master clock. Using the most stable clocks available this effect would degrade the LISA sensitivity by more than a factor of 100. This clock noise can be removed in post‐processing if the clock phase can be transferred between the spacecraft with a fidelity of a few microcycles/Hz. In the LISA baseline design, the clock phase is phase modulated onto the science lasers exchanged between spacecraft. Interference between the outgoing sidebands and the incoming sidebands contains the information necessary to remove the clock noise in post‐processing. The details of the LISA clock noise removal scheme are described and results of a recent successful demonstration of the clock noise transfer are presented.
12403529
Coil Extension, Deformation and Compression during Excitation in Superconducting Accelerator Dipole Magnets
The measurement of conductor motion, caused by exciting a superconducting dipole magnet, is compared to the measured field quality.
121615910
Room temperature field measurements of superconducting magnets
During the production of the superconducting magnets for the Fermilab Energy Doubler/Saver, it is important to closely monitor the magnetic field quality. Since it is both costly and time consuming to delay these measurements until after each magnet has been placed in a cryostat, we are developing a room temperature measurement system capable of resolving a ΔB/B smaller than 1 × 10-5.
113758813
Operational Test and Field Measurement of E5-1 Magnet. 1.
118747225
V+jets Background and Systematic Uncertainties in Top Quark Analyses
Vector boson production in association with jets is an important process to test perturbative quantum chromodynamics and also a background process in top quark analyses. Measurements on vector boson production in association with light and heavy flavour jets are presented, performed by the D0 and CDF collaborations at the Tevatron as well as the ATLAS and CMS experiments at LHC. Techniques applied in top quark analyses to estimate the vector boson+jets background are also discussed.