| Paper |
Title |
Page |
| MOPC113 |
Head-on Beam-beam Compensation with Electron Lenses in the Relativistic Heavy Ion Collider
|
328 |
| |
- Y. Luo, N. P. Abreu, E. N. Beebe, J. Beebe-Wang, C. Montag, M. Okamura, A. I. Pikin, G. Robert-Demolaize
BNL, Upton, Long Island, New York
|
|
| |
The working points for polarized proton operation in the Relativistic Heavy Ion Collider (RHIC) are currently constrained between 2/3 and 7/10, and the beam and luminosity lifetimes are limited by head-on beam-beam effects. To further increase the bunch intensity, we propose a low energy Gaussian electron beam, or electron lens, to collide head-on with the proton beam in order to compensate the large tune shift and tune spread generated by the proton-proton collisions in 2 interaction points. In this article, outline of the RHIC head-on beam-beam compensation with e-lenses and parameters for both proton and electron beams are presented.
|
|
| WEPP001 |
Energy Loss of Coasting Gold Ions and Deutrons in RHIC
|
2518 |
| |
- N. P. Abreu, M. Blaskiewicz, K. A. Brown, J. J. Butler, W. Fischer, M. Harvey, S. Tepikian
BNL, Upton, Long Island, New York
- H. Burkhardt
CERN, Geneva
|
|
| |
The total energy loss of coasting gold ion beams was measured at RHIC at two energies, corresponding to a gamma of 75.2 and 107.4. We describe the experiment and observations and compare the measured total energy loss with expectations from ionization losses at the residual gas, the energy loss due to impedance and synchrotron radiation. We find that the measured energy losses are below what is expected from free space synchrotron radiation. We believe that this shows evidence for suppression of synchrotron radiation which is cut off at long wavelength by the presence of the conducting beam pipe.
|
|
| WEPP002 |
The Effect of Head-on Beam-beam Compensation on the Stochastic Boundaries and Particle Diffusion in RHIC
|
2521 |
| |
- N. P. Abreu, W. Fischer, Y. Luo, G. Robert-Demolaize
BNL, Upton, Long Island, New York
|
|
| |
To compensate the effects from the head-on beam-beam interactions in the polarized proton operation in the Relativistic Heavy Ion Collider (RHIC), an electron lens (e-lens) is proposed to collide head-on with the proton beam. We used an extended version of SixTrack for multiparticle beam-beam simulation in order to study the effect of the e-lens on the stochastic boundary and also on diffusion. The stochastic boundary was analyzed using Lypunov exponents and the diffusion was characterized as the average rms spread of the action after 104 turns. For both studies the simulations were performed with and without the e-lens and with full and partial compensation.
|
|
| WEPP011 |
Setup and Performance of RHIC for the 2008 Run with Deuteron and Gold Collisions
|
2548 |
| |
- C. J. Gardner, N. P. Abreu, L. Ahrens, J. G. Alessi, M. Bai, D. S. Barton, J. Beebe-Wang, M. Blaskiewicz, J. M. Brennan, K. A. Brown, D. Bruno, J. J. Butler, P. Cameron, C. Carlson, R. Connolly, T. D'Ottavio, A. J. Della Penna, K. A. Drees, W. Fischer, W. Fu, G. Ganetis, J. W. Glenn, M. Harvey, T. Hayes, H. Huang, P. F. Ingrassia, J. Kewisch, R. C. Lee, V. Litvinenko, Y. Luo, W. W. MacKay, M. Mapes, G. J. Marr, A. Marusic, R. J. Michnoff, C. Montag, J. Morris, B. Oerter, F. C. Pilat, E. Pozdeyev, V. Ptitsyn, G. Robert-Demolaize, T. Roser, T. Russo, P. Sampson, J. Sandberg, T. Satogata, C. Schultheiss, F. Severino, K. Smith, D. Steski, S. Tepikian, R. Than, P. Thieberger, D. Trbojevic, N. Tsoupas, J. E. Tuozzolo, A. Zaltsman, K. Zeno, S. Y. Zhang
BNL, Upton, Long Island, New York
|
|
| |
This year deuterons and gold ions were collided in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) for the first time since 2003. The setup and performance of the collider for this run is reviewed with a focus on improvements that have led to an order of magnitude increase in luminosity since the 2003 run.
|
|
| WEPP019 |
RHIC Polarized Proton Performance in Run-8
|
2566 |
| |
- C. Montag, N. P. Abreu, L. Ahrens, M. Bai, D. S. Barton, A. Bazilevsky, J. Beebe-Wang, M. Blaskiewicz, J. M. Brennan, K. A. Brown, D. Bruno, G. Bunce, R. Calaga, P. Cameron, R. Connolly, T. D'Ottavio, K. A. Drees, A. V. Fedotov, W. Fischer, G. Ganetis, C. J. Gardner, J. W. Glenn, T. Hayes, H. Huang, P. F. Ingrassia, A. Kayran, J. Kewisch, R. C. Lee, V. Litvinenko, A. U. Luccio, Y. Luo, W. W. MacKay, Y. Makdisi, N. Malitsky, G. J. Marr, A. Marusic, R. J. Michnoff, J. Morris, B. Oerter, H. Okada, F. C. Pilat, P. H. Pile, G. Robert-Demolaize, T. Roser, T. Russo, T. Satogata, C. Schultheiss, M. Sivertz, K. Smith, S. Tepikian, D. Trbojevic, N. Tsoupas, J. E. Tuozzolo, A. Zaltsman, A. Zelenski, K. Zeno, S. Y. Zhang
BNL, Upton, Long Island, New York
|
|
| |
During Run-8, the Relativistic Heavy Ion Collider (RHIC) provided collisions of spin-polarized proton beams at two interaction regions. Helical spin rotators at these two interaction regions were used to control the spin orientation of both beams at the collision points. Physics data were taken with different orientations of the beam polarization. We present recent developments and improvements as well as the luminosity and polarization performance achieved during Run-8.
|
|
| THPC059 |
Studies of Wire Compensation and Beam-beam Interaction in RHIC
|
3119 |
| |
- H. J. Kim, T. Sen
Fermilab, Batavia, Illinois
- N. P. Abreu, W. Fischer
BNL, Upton, Long Island, New York
|
|
| |
Beam-beam interaction is one of the dominant source of emittance growth and luminosity lifetime deterioration. A current carrying wire has been proposed to compensate long-range beam-beam effects in the LHC and the principle is now being experimentally investigated at RHIC. In this paper, we use simulations to study the effectiveness of wire compensation based on tune footprints, diffusive apertures, and beam loss rates using a parallel weak-strong beam simulation code (BBSIM). In addition we extensively study the diffusion properties of RHIC beams for different beam and wire parameters. Beam-beam effects on emittance growth are investigated through the solution of the diffusion equation for the transverse action variables.
|
|
| THPC062 |
Multi-Particle Weak-Strong Simulations of RHIC Head-on Beam-Beam Compensation
|
3125 |
| |
- Y. Luo, N. P. Abreu, W. Fischer, G. Robert-Demolaize
BNL, Upton, Long Island, New York
|
|
| |
An electron beam has been proposed in the Relativistic Heavy Ion Collider (RHIC) to compensate beam-beam effects in polarized proton collisions. This electron beam will collide head-on with the proton beam. Using the weak-strong beam-beam interaction model, we have carried out six-dimensional multiparticle simulations to investigate the effects of head-on beam-beam compensation. Beam lifetime, transverse emittances, and luminosity are calculated for cases with and without beam-beam compensation for up to 10 million turns. The migrations of particles between different actions and the beam spectrum are also calculated.
|
|
| THPC113 |
Feedback Damper System for Quadrupole Oscillations after Transition at RHIC
|
3242 |
| |
- N. P. Abreu, M. Blaskiewicz, J. M. Brennan, C. Schultheiss
BNL, Upton, Long Island, New York
|
|
| |
The heavy ion beam at RHIC undergoes a strong quadrupole oscillations just after it crosses transition, which in turn leads to an increase in bunch length making rebucketing less effective. A feedback system was built to damp these quadrupole oscillations and in this paper the characteristics of the system and the results obtained are presented and discussed.
|
|