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Coherent electron cooling demonstration experiment (open access)

Coherent electron cooling demonstration experiment

Coherent electron cooling (CEC) has a potential to significantly boost luminosity of high-energy, high-intensity hadron-hadron and electron-hadron colliders. In a CEC system, a hadron beam interacts with a cooling electron beam. A perturbation of the electron density caused by ions is amplified and fed back to the ions to reduce the energy spread and the emittance of the ion beam. To demonstrate the feasibility of CEC we propose a proof-of-principle experiment at RHIC using SRF linac. In this paper, we describe the setup for CeC installed into one of RHIC's interaction regions. We present results of analytical estimates and results of initial simulations of cooling a gold-ion beam at 40 GeV/u energy via CeC. We plan to complete the program in five years. During first two years we will build coherent electron cooler in IP2 of RHIC. In parallel we will develop complete package of computer simulation tools for the start-to-end simulation predicting exact performance of a CeC. The later activity will be the core of Tech X involvement into the project. We will use these tools to predict the performance of our CeC device. The experimental demonstration of the CeC will be undertaken in years three to five of …
Date: September 4, 2011
Creator: Litvinenko, V. N.; Belomestnykh, S.; Ben-Zvi, Ilan; Brutus, J. C.; Fedotov, A.; Hao, Y. et al.
Object Type: Article
System: The UNT Digital Library
Recommendation for Mitigations of the Electron Cloud Instability in the ILC (open access)

Recommendation for Mitigations of the Electron Cloud Instability in the ILC

Electron cloud has been identified as one of the highest priority issues for the international Linear Collider (ILC) Damping Rings (DR). An electron cloud Working Group (WG) has evaluated the electron cloud effect and instability, and mitigation solutions for the electron cloud formation. Working group deliverables include recommendations for the baseline and alternate solutions to the electron cloud formation in various regions of the ILC Positron DR, which is presently assumed to be the 3.2 km design. Detailed studies of a range of mitigation options including coatings, clearing electrodes, grooves and novel concepts, were carried out over the previous several years by nearly 50 researchers, and the results of the studies form the basis for the recommendation. The recommendations are the result of the working group discussions held at numerous meetings and during a dedicated workshop. In addition, a number of items requiring further investigation were identified during the discussions at the Cornell meeting and studies will be carried out at CesrTA, a test accelerator dedicated to electron cloud studies, and other institutions.
Date: September 4, 2011
Creator: Pivi, M. T. F.; Wang, L.; Demma, T.; Guiducci, S.; Suetsugu, Y.; Shibata, K. et al.
Object Type: Article
System: The UNT Digital Library
A Non-scaling Fixed Field Alternating Gradient Accelerator for the Final Acceleration Stage of the International Design Study of the Neutrino Factory. (open access)

A Non-scaling Fixed Field Alternating Gradient Accelerator for the Final Acceleration Stage of the International Design Study of the Neutrino Factory.

The International Design Study of the Neutrino Factory (IDS-NF) has recently completed its Interim Design Report (IDR), which presents our current baseline design of the neutrino factory. To increase the efficiency and reduce the cost of acceleration, the IDR design uses a linear non-scaling fixed field alternating gradient accelerator (FFAG) for its final acceleration stage. We present the current lattice design of that FFAG, including the main ring plus its injection and extraction systems. We describe parameters for the main ring magnets, kickers, and septa, as well as the power supplies for the kickers. We present a first pass at an engineering layout for the ring and its subsystems.
Date: September 4, 2011
Creator: Berg, J. S.; Aslaninejad, M.; Pasternak, J.; Witte, H.; Bliss, N.; Cordwell M. et al.
Object Type: Article
System: The UNT Digital Library
The Graham Leader (Graham, Tex.), Vol. 136, No. 6, Ed. 1 Sunday, September 4, 2011 (open access)

The Graham Leader (Graham, Tex.), Vol. 136, No. 6, Ed. 1 Sunday, September 4, 2011

Semiweekly newspaper from Graham, Texas that includes local, state, and national news along with advertising.
Date: September 4, 2011
Creator: Rupkalvis, David
Object Type: Newspaper
System: The Portal to Texas History
Sweetwater Reporter (Sweetwater, Tex.), Vol. 113, No. 249, Ed. 1 Sunday, September 4, 2011 (open access)

Sweetwater Reporter (Sweetwater, Tex.), Vol. 113, No. 249, Ed. 1 Sunday, September 4, 2011

Daily newspaper from Sweetwater, Texas that includes local, state, and national news along with advertising.
Date: September 4, 2011
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Stochastic cooling of a high energy collider (open access)

Stochastic cooling of a high energy collider

Gold beams in RHIC revolve more than a billion times over the course of a data acquisition session or store. During operations with these heavy ions the event rates in the detectors decay as the beams diffuse. A primary cause for this beam diffusion is small angle Coloumb scattering of the particles within the bunches. This intra-beam scattering (IBS) is particularly problematic at high energy because the negative mass effect removes the possibility of even approximate thermal equilibrium. Stochastic cooling can combat IBS. A theory of bunched beam cooling was developed in the early eighties and stochastic cooling systems for the SPS and the Tevatron were explored. Cooling for heavy ions in RHIC was also considered.
Date: September 4, 2011
Creator: Blaskiewicz, M.; Brennan, J. M.; Lee, R. C. & Mernick, K.
Object Type: Article
System: The UNT Digital Library
The EMMA Accelerator, a Diagnostic Systems Overview (open access)

The EMMA Accelerator, a Diagnostic Systems Overview

The 'EMMA' Non-Scaling Fixed Field Alternating Gradient (ns-FFAG) international project is currently being commissioned at Daresbury Laboratory, UK. This accelerator has been equipped with a number of diagnostic systems to facilitate this. These systems include a novel time-domain-multiplexing BPM system, moveable screen systems, a time-of-flight instrument, Faraday cups, and injection/extraction tomography sections to analyze the single bunch beams. An upgrade still to implement includes the installation of wall current monitors. This paper gives an overview of these systems and shows some data and results from the diagnostics that have contributed to the successful demonstration of a serpentine acceleration by this novel accelerator.
Date: September 4, 2011
Creator: Kalinin, A.; Berg, J.; Bliss, N. Cox, G.; Dufau, M.; Gallagher, A.; Hill, C. et al.
Object Type: Article
System: The UNT Digital Library
Status of Studies of Achromat-based 6D Ionization Cooling Rings for Muons (open access)

Status of Studies of Achromat-based 6D Ionization Cooling Rings for Muons

Six dimensional ionization cooling of muons is needed to achieve the necessary luminosity for a muon collider. If that cooling could occur over multiple turns in a closed ring, there would be significant cost savings over a single-pass cooling channel. We report on the status of a cooling ring with achromatic arcs. The achromatic design permits the design to easily switch between a closed ring and a snaking geometry on injection or extraction from the ring. The ring is designed with sufficient space in each superperiod for injection and extraction magnets. We describe the ring's lattice design, performance, and injection/extraction requirements.
Date: September 4, 2011
Creator: Ding, X.; Kirk, H.; Cline, D.; Garren, A. A. & Berg, J. S.
Object Type: Article
System: The UNT Digital Library
RHIC Performance for FY2011 Au+Au Heavy Ion Run (open access)

RHIC Performance for FY2011 Au+Au Heavy Ion Run

Following the Fiscal Year (FY) 2010 (Run-10) Relativistic Heavy Ion Collider (RHIC) Au+Au run, RHIC experiment upgrades sought to improve detector capabilities. In turn, accelerator improvements were made to improve the luminosity available to the experiments for this run (Run-11). These improvements included: a redesign of the stochastic cooling systems for improved reliability; a relocation of 'common' RF cavities to alleviate intensity limits due to beam loading; and an improved usage of feedback systems to control orbit, tune and coupling during energy ramps as well as while colliding at top energy. We present an overview of changes to the Collider and review the performance of the collider with respect to instantaneous and integrated luminosity goals. At the conclusion of the FY 2011 polarized proton run, preparations for heavy ion run proceeded on April 18, with Au+Au collisions continuing through June 28. Our standard operations at 100 GeV/nucleon beam energy was bracketed by two shorter periods of collisions at lower energies (9.8 and 13.5 GeV/nucleon), continuing a previously established program of low and medium energy runs. Table 1 summarizes our history of heavy ion operations at RHIC.
Date: September 4, 2011
Creator: Marr, G.; Ahrens, L.; Bai, M.; Beebe-Wang, J.; Blackler, I.; Blaskiewicz, M. et al.
Object Type: Article
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 112, No. 105, Ed. 1 Sunday, September 4, 2011 (open access)

The Altus Times (Altus, Okla.), Vol. 112, No. 105, Ed. 1 Sunday, September 4, 2011

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: September 4, 2011
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 91, No. 173, Ed. 1 Sunday, September 4, 2011 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 91, No. 173, Ed. 1 Sunday, September 4, 2011

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: September 4, 2011
Creator: Gray, Janie
Object Type: Newspaper
System: The Portal to Texas History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 96, No. 249, Ed. 1 Sunday, September 4, 2011 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 96, No. 249, Ed. 1 Sunday, September 4, 2011

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: September 4, 2011
Creator: Harmon, C. L.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Polk County Enterprise (Livingston, Tex.), Vol. 129, No. 70, Ed. 1 Sunday, September 4, 2011 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 129, No. 70, Ed. 1 Sunday, September 4, 2011

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: September 4, 2011
Creator: Reddell, Valerie
Object Type: Newspaper
System: The Portal to Texas History
The Panola Watchman (Carthage, Tex.), Vol. 139, No. 71, Ed. 1 Sunday, September 4, 2011 (open access)

The Panola Watchman (Carthage, Tex.), Vol. 139, No. 71, Ed. 1 Sunday, September 4, 2011

Semiweekly newspaper from Carthage, Texas that includes local, state, and national news along with advertising.
Date: September 4, 2011
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Enjoy a Blue Ribbon Ride to the Fair (open access)

Enjoy a Blue Ribbon Ride to the Fair

News release about DART transportation services to the State Fair of Texas.
Date: September 4, 2011
Creator: Lyons, Morgan & Ball, Mark
Object Type: Text
System: The Portal to Texas History