| Paper | Title | Page |
|---|---|---|
| TUPAS031 | Analysis of Optics Designs for the LHC IR Upgrade | 1718 |
|
||
| We consider the different options proposed for the LHC IR upgrade. The two main categories: quadrupoles first (as in the baseline design) and dipoles first have complementary strengths. We analyse the potential of the proposed designs by calculating important performance parameters including luminosity reach, beam-beam resonances and chromaticity contributions. The goal is to enable a decision on the design path based on objective criteria. | ||
| TUPAS032 | Prospects of Diagnostics with Optical Diffraction Radiation in Hadron Colliders | 1721 |
|
||
| Optical diffraction radiation has been observed and recently used to measure the beam size of electrons at KEK. This non-invasive technique also holds promise for imaging beams close to the interaction point in hadron colliders. In this paper we consider the feasibility of this technique for the Tevatron and the LHC. | ||
| THPAN114 | Simulations of Beam-wire Experiments at RHIC | 3492 |
|
||
| We report on simulations of beam-beam experiments performed at RHIC in 2006. These experiments were designed to observe the influence of a single parasitic interaction on beam quality. Several observables such as tunes, emittances and losses were simulated with the weak-strong code BBSIM. These simulation results are compared to observed values. Simulations of the wire compensation experiment to be carried out in RHIC are also shown. | ||
| TUPAS095 | Experiments with a DC Wire in RHIC | 1859 |
|
||
|
Funding: Work supported by U. S. DOE under contract No DE-AC02-98CH1-886. A DC wire has been installed in RHIC to explore the long-range beam-beam effect, and test its compensation. We report on experiments that measure the effect of the wire's electro-magnetic field on the beam's lifetime and tune distribution, and accompanying simulations. |
||
| THPAS062 | Recent Progress in a Beam-Beam Simulation Code for Circular Hadron Machines | 3627 |
|
||
| Over the past years, we have developed a set of codes (PLIBB and NIMZOVICH) applicable to weak-strong and strong-strong beam-beam interactions in hadron machines. We have unified these codes into a single application and augmented the modeled physics to include arbitrary-order magnetic elements, noise sources and wire compensators; algorithmic improvements include diferential-algebraic methods, thick magnetic elements, and a fully-coupled, six-dimensional and symplectic treatment of lumped sections. A novel weighted-macroparticle approach allows for the immediate calculation of very low beam loss rates by particle tracking. The parallelization scheme of the code allows for a highly efficient simulation of colliders with a high number of parasitic crossings and/or pronounced hourglass effect in the IP. Areas of applicability include the LHC and the wire-compensation experiments performed at RHIC. Typical results will be presented. | ||
| FRPMS026 | Strong-Strong Simulation of Long-Range Beam-Beam Effects at RHIC | 3979 |
|
||
|
Funding: This work was supported by the U. S. Department of Energy under Contract no. DE-AC02-05CH11231. Long-range beam-beam interactions can cause significant degrade of beam quality and lifetime in high energy ring colliders. At RHIC, a series of experiments were carried out to study these effects. In this paper, we report on numerical simulation of the long-range beam-beam interactions at RHIC using a parallel strong-strong particle-in-cell code, BeamBeam3D. The simulation includes nonlinearities from both the beam-beam interactions and the arc sextupoles. We observed significant emittance growth for beam separation below 4 σs under nominal tunes. A scan study in tune space shows strong emittance growth around 7th order resonance. Including the tune modulation due to chromaticity and synchrotron motion shows larger emittance growth than the case without the tune modulation. |