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Comment on the Word 'Cooling' as it is Used in Beam Physics

Description: The Institute of Medicine (IOM) of the National Academy of Sciences recently completed a critical review of the scientific literature pertaining to the association of indoor dampness and mold contamination with adverse health effects. In this paper, we report the results of quantitative meta-analysis of the studies reviewed in the IOM report. We developed point estimates and confidence intervals (CIs) to summarize the association of several respiratory and asthma-related health outcomes with the presence of dampness and mold in homes. The odds ratios and confidence intervals from the original studies were transformed to the log scale and random effect models were applied to the log odds ratios and their variance. Models were constructed both accounting for the correlation between multiple results within the studies analyzed and ignoring such potential correlation. Central estimates of ORs for the health outcomes ranged from 1.32 to 2.10, with most central estimates between 1.3 and 1.8. Confidence intervals (95%) excluded unity except in two of 28 instances, and in most cases the lower bound of the CI exceeded 1.2. In general, the two meta-analysis methods produced similar estimates for ORs and CIs. Based on the results of the meta-analyses, building dampness and mold are associated with approximately 30% to 80% increases in a variety of respiratory and asthma-related health outcomes. The results of these meta-analyses reinforce the IOM's recommendation that actions be taken to prevent and reduce building dampness problems.
Date: September 10, 2005
Creator: Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department

Beam cooling: Principles and achievements

Description: After a discussion of Liouville's theorem, and its implications for beam cooling, a brief description is given of each of the various methods of beam cooling: stochastic, electron, radiation, laser, ionization, etc. For each, we present the type of particle for which it is appropriate, its range of applicability, and the currently achieved degree of cooling. For each method we also discuss the present applications and, also, possible future developments and further applications.
Date: May 18, 2003
Creator: Mohl, Dieter & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department

Tevatron electron lens and it's applications

Description: The Tevatron Electron Lens (TEL) is designed for the purpose of the Beam-beam tuneshift compensation. Now it's one of the vital parts of the Tevatron. In this report, its daily operations and beam study results are presented. And its possible future applications are also discussed as well.
Date: August 1, 2009
Creator: Zhang, X.L.; Shiltsev, V.; Valishev, A.; /Fermilab; Kamerdzhiev, V.; /Julich, Forschungszentrum et al.
Partner: UNT Libraries Government Documents Department

Antiproton stacking in the Recycler

Description: Possibilities to accumulate antiprotons in the Recycler are considered for three different cases: with current stochastic cooling, with upgraded stochastic cooling and with electron cooling. With stochastic cooling only, even upgraded, Recycler looks hardly useful. However, with electron cooling at its goal parameters and reasonably good vacuum in the Recycler, this machine would be efficient.
Date: June 23, 2003
Creator: Burov, Alexey
Partner: UNT Libraries Government Documents Department

Stochastic cooling overview

Description: The status of stochastic cooling and developments over the years are reviewed with reference to much of the original work. Both theoretical and technological subjects are considered.
Date: July 1, 2003
Creator: Marriner, John P
Partner: UNT Libraries Government Documents Department

Methods of beam cooling

Description: Diverse methods which are available for particle beam cooling are reviewed. They consist of some highly developed techniques such as radiation damping, electron cooling, stochastic cooling and the more recently developed, laser cooling. Methods which have been theoretically developed, but not yet achieved experimentally, are also reviewed. They consist of ionization cooling, laser cooling in three dimensions and stimulated radiation cooling.
Date: February 1, 1996
Creator: Sessler, A.M.
Partner: UNT Libraries Government Documents Department

Muon Collider: Muon Generation, Capture and Cooling

Description: A {mu}{sup +} -{mu}{sup -} collider requires a high-intensity proton source for {pi}-production, a high-acceptance {pi}-{mu} decay channel, a {mu}-cooling system, a rapid acceleration system, and a high-luminosity collider ring for the collision of short, intense {mu}{sup +} -{mu}{sup -} bunches. Critical problems exist in developing and compressing high-energy proton bunches for producing {pi}�s, in capturing {pi}�s and their decay {mu}�s, and in cooling {mu}�s into a compressed phase-space at which high luminosity collisions are possible. These problems and some possible solutions are discussed; the current {mu}{sup +} -{mu}{sup -} collider research program is described
Date: February 16, 1999
Creator: Neuffer, David
Partner: UNT Libraries Government Documents Department

An insertion to eliminate horizontal temperature of high energy electron beam

Description: High energy electron cooling with a circulated electron bunch could significantly increase the luminosity of hadron colliders. One of the significant obstacles is high horizontal temperature of electron bunches, suppressing dramatically calculated cooling rates. Recently, a transformation of betatron coordinates and angles for elimination of the radial temperature was found. In our paper, we present a simple scheme to make up this transformation by thin quadruples, drifts and a solenoid.
Date: March 16, 1998
Creator: Burov, A.V. & Danilov, V.V.
Partner: UNT Libraries Government Documents Department

An ionization cooling channel for muon beams based on alternating solenoids

Description: The muon collider requires intense, cooled muon bunches to reach the required luminosity. Due to the limited life-time of the muon, the cooling process must take place very rapidly. Ionization cooling seems to be our only option, given the large emittances of the muon beam from pion decay. However, this ionization cooling method has been found quite difficult to implement in practice. We describe a scheme based on the use of liquid hydrogen absorbers fol-lowed by r.f. cavities (�pillbox� or �open iris� type), em-bedded in a transport lattice based on high field solenoids. These solenoidal fields are reversed periodically in order to suppress the growth of the canonical angular momentum. This channel has been simulated in detail with independent codes, featuring conventional tracking in e.m. fields and de-tailed simulation of multiple scattering and straggling in the the absorbers and windows. These calculations show that the 15 Tesla lattice cools in 6-Dphase space by a factor {approx} 2 over a distance of 20 m.
Date: April 16, 1999
Creator: al., Juan C. Gallardo et
Partner: UNT Libraries Government Documents Department

Possible demonstration of ionization cooling using absorbers in a solenoidal field

Description: Ionization cooling may play an important role in reducing the phase space volume of muons for a future muon-muon collider. We describe a possible experiment to demonstrate transverse emittance cooling using a muon beam at the AGS at Brookhaven National Laboratory. The experiment uses device dimensions and parameters and beam conditions similar to what is expected in an actual muon-muon collider.
Date: December 1, 1995
Creator: Fernow, R.C.; Gallardo, J.C. & Kirk, H.G.
Partner: UNT Libraries Government Documents Department

Final Technical Report on STTR Project DE-FG02-02ER86145 Pressurized RF Cavities for Muon Ionization Cooling

Description: This project was to design and build an RF test cell (TC), which could be operated at 800 MHz, filled with high pressure gases including hydrogen, at temperatures down to that of liquid nitrogen, in strong magnetic fields, in a strong radiation environment, and with interchangeable electrodes, in order to examine the use of high-pressure RF cavities for muon beam cooling.
Date: July 13, 2006
Creator: Johnson, Rolland
Partner: UNT Libraries Government Documents Department

RHIC and its upgrade programmes.

Description: As the first hadron accelerator and collider consisting of two independent superconducting rings RHIC has operated with a wide range of beam energies and particle species. After a brief review of the achieved performance the presentation will give an overview of the plans, challenges and status of machine upgrades, that range from a new heavy ion pre-injector and beam cooling at 100 GeV to a high luminosity electron-ion collider.
Date: June 23, 2008
Creator: Roser,T.
Partner: UNT Libraries Government Documents Department


Description: Lattice for a 3-GeV cooler ring with split functions is presented. The ring consists of two half-rings of different properties: in one half-ring, the phase-slip factor is near-zero; in the other half-ring, the phase-slip factor is large. The near-zero phase slip minimizes the 'bad mixing' between the stochastic-cooling pick-ups and kickers, while the high phase slip maximizes the 'good mixing' between the kickers and the next-turn pick-ups.
Date: September 10, 2007
Creator: WEI,J.
Partner: UNT Libraries Government Documents Department


Description: Recent theoretical investigations of beam crystallization using computer modeling based on the method of molecular dynamics (MD) and analytical approach based on the phonon theory are motivated by the study of colliding crystalline beams [4]. Analytical study of crystal stability in an alternating-gradient (AG) focusing ring was previously limited to the smooth approximation. In a typical ring, results obtained under such approximation largely agrees with that obtained with the MD simulation. However, as we explore ring lattices appropriate for beam crystallization at high energies (Lorentz factor y much larger than the transverse tunes v,, vy) [5], this approximation fails. Here, we present a newly developed phonon theory in a time-dependent Hamiltonian system representing the actual AG-focusing ring and predict the stability of 1D crystals at high energies. Luminosity enhancement is illustrated in examples of rare-ion colliders based on ordered 1D strings of ions.
Date: September 10, 2007
Creator: WEI,J.
Partner: UNT Libraries Government Documents Department


Description: With the experimental success of longitudinal, bunched beam stochastic cooling in RHIC it is natural to ask whether the system works as well as it might and whether upgrades or new systems are warranted. A computer code, very similar to those used for multi-particle coherent instability simulations, has been written and is being used to address these questions.
Date: September 10, 2007
Partner: UNT Libraries Government Documents Department


Description: A 0.1-0.5 A, 4.3 MeV DC electron beam provides cooling of 8 GeV antiprotons in Fermilab's Recycler storage ring. The most detailed information about the cooling properties of the electron beam comes from drag rate measurements. We find that the measured drag rate can significantly differ from the cooling force experienced by a single antiproton because the area of effective cooling is significantly smaller than the physical size of the electron beam and is comparable with the size of the antiproton beam used as a probe. Modeling by the BETACOOL code supports the conclusion about a large radial gradient of transverse velocities in the presently used electron beam.
Date: September 10, 2007
Partner: UNT Libraries Government Documents Department

Characteristics of a High Energy {mu sup +}{mu sup -} Collider Based on Electro-Production of Muons

Description: We analyze the design of an high energy {mu}{sup +}{mu}{sup -} collider based on electro-production of muons. We derive an expression for the luminosity in terms of analytic formulae for the electron-to-muon conversion efficiency and the electron beam power on the production target On the basis of studies of self-consistent sets of collider parameters under 'realistic' ('optimistic') assumptions about available technology with beam cooling, we find the luminosity limited to 10{sup 27} m{sup -2}s{sup -1} (10{sup 28} m{sup -2}s{sup -1}). We also identify major technological innovations that will be required before {mu}{sup +}{mu}{sup -} colliders can offer sufficient luminosity (10{sup 30} cm{sup -2}s{sup -1}) for high energy physics research.
Date: January 9, 1993
Creator: Barletta, W.A. & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department

The MuCool Test Area and RF Program

Description: The MuCool RF Program focuses on the study of normal conducting RF structures operating in high magnetic field for applications in muon ionization cooling for Neutrino Factories and Muon Colliders. This paper will give an overview of the program, which will include a description of the test facility and its capabilities, the current test program, and the status of a cavity that can be rotated in the magnetic field which allows for a more detailed study of the maximum stable operating gradient vs. magnetic field strength and angle.
Date: May 1, 2010
Creator: Bross, A. D.; Jansson, A.; Moretti, A.; Yonehara, K.; Huang, D.; Torun, Y. et al.
Partner: UNT Libraries Government Documents Department

RF Integration into Helical Magnet for Muon 6-Dimensional Beam Cooling

Description: The helical cooling channel is proposed to make a quick muon beam phase space cooling in a short channel length. The challenging part of the helical cooling channel magnet design is how to integrate the RF cavity into the compact helical cooling magnet. This report shows the possibility of the integration of the system.
Date: May 1, 2009
Creator: Yonehara, K.; Kashikhin, V.; Lamm, M.; Lee, A.; Lopes, M.; Zlobin, A. et al.
Partner: UNT Libraries Government Documents Department

Performance and upgrades of the Fermilab Accumulator stacktail stochastic cooling

Description: We report on the performance and planned upgrades to the Fermilab Accumulator Stacktail Stochastic Cooling System. The current system has achieved a maximum flux of 16.5e10/hour, limited by the input flux of antiprotons. The upgrades are designed to handle flux in excess of 40e10/hour.
Date: November 1, 2005
Creator: Derwent, P.F.; Cullerton, Ed; McGinnis, David; Pasquinelli, Ralph; Sun, Ding; Tinsley, David et al.
Partner: UNT Libraries Government Documents Department

Debuncher cooling performance

Description: We present measurements of the Fermilab Debuncher momentum and transverse cooling systems. These systems use liquid helium cooled waveguide pickups and slotted waveguide kickers covering the frequency range 4-8 GHz.
Date: November 1, 2005
Creator: Derwent, P.F.; McGinnis, David; Pasquinelli, Ralph; Vander Meulen, David; Werkema, Steven & /Fermilab
Partner: UNT Libraries Government Documents Department

IBS in a CAM-Dominated Electron Beam

Description: We report on the performance and planned upgrades to the Fermilab Accumulator Stacktail Stochastic Cooling System. The current system has achieved a maximum flux of 16.5e10/hour, limited by the input flux of antiprotons. The upgrades are designed to handle flux in excess of 40e10/hour.
Date: December 1, 2005
Creator: Burov, Alexey V.; /Fermilab; Gusachenko, I.; U., /Novosibirsk State; Nagaitsev, S.; /Fermilab et al.
Partner: UNT Libraries Government Documents Department

Cooling in a compound bucket

Description: Electron cooling in the Fermilab Recycler ring is found to create correlation between longitudinal and transverse tails of the antiproton distribution. By separating the core of the beam from the tail and cooling the tail using 'gated' stochastic cooling while applying electron cooling on the entire beam, one may be able to significantly increase the overall cooling rate. In this paper, we describe the procedure and first experimental results.
Date: September 1, 2007
Creator: Shemyakin, A.; Bhat, C.; Broemmelsiek, D.; Burov, A.; Hu, M. & /Fermilab
Partner: UNT Libraries Government Documents Department