Small high cooling power space cooler

Energy Technology Data Exchange (ETDEWEB)

Nguyen, T. V.; Raab, J.; Durand, D.; Tward, E. [Northrop Grumman Aerospace Systems Redondo Beach, Ca, 90278 (United States)

2014-01-29

The small High Efficiency pulse tube Cooler (HEC) cooler, that has been produced and flown on a number of space infrared instruments, was originally designed to provide cooling of 10 W @ 95 K. It achieved its goal with >50% margin when limited by the 180 W output ac power of its flight electronics. It has also been produced in 2 stage configurations, typically for simultaneously cooling of focal planes to temperatures as low as 35 K and optics at higher temperatures. The need for even higher cooling power in such a low mass cryocooler is motivated by the advent of large focal plane arrays. With the current availability at NGAS of much larger power cryocooler flight electronics, reliable long term operation in space with much larger cooling powers is now possible with the flight proven 4 kg HEC mechanical cooler. Even though the single stage cooler design can be re-qualified for those larger input powers without design change, we redesigned both the linear and coaxial version passive pulse tube cold heads to re-optimize them for high power cooling at temperatures above 130 K while rejecting heat to 300 K. Small changes to the regenerator packing, the re-optimization of the tuned inertance and no change to the compressor resulted in the increased performance at 150 K. The cooler operating at 290 W input power achieves 35 W@ 150 K corresponding to a specific cooling power at 150 K of 8.25 W/W and a very high specific power of 72.5 W/Kg. At these powers the cooler still maintains large stroke, thermal and current margins. In this paper we will present the measured data and the changes to this flight proven cooler that were made to achieve this increased performance.

The RHIC general purpose multiplexed analog to digital converter system

International Nuclear Information System (INIS)

Michnoff, R.

1995-01-01

A general purpose multiplexed analog to digital converter system is currently under development to support acquisition of analog signals for the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. The system consists of a custom intelligent VME based controller module (V113) and a 14-bit 64 channel multiplexed A/D converter module (V114). The design features two independent scan groups, where one scan group is capable of acquiring 64 channels at 60 Hz, concurrently with the second scan group acquiring data at an aggregate rate of up to 80 k samples/second. An interface to the RHIC serially encoded event line is used to synchronize acquisition. Data is stored in a circular static RAM buffer on the controller module, then transferred to a commercial VMEbus CPU board and higher level workstations for plotting, report Generation, analysis and storage

Impulse sales cooler. Final report

Energy Technology Data Exchange (ETDEWEB)

Pedersen, Per Henrik (DTI, Taastrup (Denmark))

2010-11-15

In the past years, the use of impulse coolers has increased considerably and it is estimated that at least 30.000 are installed in shops in Denmark. In addition, there are many small barrel-shaped can coolers. Most impulse coolers are open, which results in a large consumption of energy, and the refrigeration systems are often quite inefficient. A typical impulse cooler uses app. 5 - 8 kWh/day corresponding to a consumption of energy in the magnitude of 60 GWh/year. For several years, the Danish company Vestfrost A/S has produced an impulse sales cooler in the high-efficiency end and the energy consumption of the cooler is measured to be 4.15 kWh/day. The POS72 cooler formed the baseline of this project. At the start-up meeting in 2008, several ideas were discussed with the objective to reduce energy consumption and to use natural refrigerants. Among the ideas were better air curtains, removable lids, better condensers, use of R600a refrigeration system and better insulation. Three generations of prototypes were built and tested in a climate chamber at Danish Technological Institute and the third generation showed very good performance: the energy consumption was measured to 2.215 kWh/day, which is a 47% reduction compared to the baseline. That was achieved by: 1) Improving the cold air cycling system including the air curtain. 2) Using the natural refrigerant R600a (isobutane) and the Danfoss NLE9KTK compressor, which has better efficiency compared to the compressor in the baseline product. 3) Using a box type condenser without fins (preventing dust build-up) and with a relatively high surface area. 4) Improving the insulation value of the plastic cabinet by reducing turbulence in the air gap between the plastic walls and improving the insulation value of the EPS moulded insulation surrounding the refrigeration system at the bottom of the cooler. 5) Preventing short-circuit of warm air around the condenser. 6) The improvements are cost efficient and will not add

Opportunities for Drell-Yan Physics at RHIC

Energy Technology Data Exchange (ETDEWEB)

Aschenauer, E.; Bland, L.; Crawford, H.; Goto, Y.; Eyser, O.; Kang, Z.; Vossen, A.

2011-05-24

Drell-Yan (DY) physics gives the unique opportunity to study the parton structure of nucleons in an experimentally and theoretically clean way. With the availability of polarized proton-proton collisions and asymmetric d+Au collisions at the Relativistic Heavy Ion Collider (RHIC), we have the basic (and unique in the world) tools to address several fundamental questions in QCD, including the expected gluon saturation at low partonic momenta and the universality of transverse momentum dependent parton distribution functions. A Drell-Yan program at RHIC is tied closely to the core physics questions of a possible future electron-ion collider, eRHIC. The more than 80 participants of this workshop focused on recent progress in these areas by both theory and experiment, trying to address imminent questions for the near and mid-term future.

RHIC FY15 pp Run RHIC and AGS polarization analysis

Energy Technology Data Exchange (ETDEWEB)

Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Adams, P. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2016-02-20

The polarization information is important for the spin physics program in Relativistic Heavy Ion Collider (RHIC). There are discrepancies between AGS and RHIC polarization measurements. First, the face value of AGS polarization is higher than RHIC ones in general. Second, the measured polarization profile (described by the profile ratio R) is stronger in AGS than in RHIC. This note analyzes the polarization data from FY15 pp run period. The results show that the differences between AGS and RHIC polarization measurements are reasonable, but the R value difference is puzzling. The difference between blue and yellow ring is worth of spin simulation to explain.

Electron Cooling of RHIC

CERN Document Server

Ben-Zvi, Ilan; Barton, Donald; Beavis, Dana; Blaskiewicz, Michael; Bluem, Hans; Brennan, Joseph M; Bruhwiler, David L; Burger, Al; Burov, Alexey; Burrill, Andrew; Calaga, Rama; Cameron, Peter; Chang, Xiangyun; Cole, Michael; Connolly, Roger; Delayen, Jean R; Derbenev, Yaroslav S; Eidelman, Yury I; Favale, Anthony; Fedotov, Alexei V; Fischer, Wolfram; Funk, L W; Gassner, David M; Hahn, Harald; Harrison, Michael; Hershcovitch, Ady; Holmes, Douglas; Hseuh Hsiao Chaun; Johnson, Peter; Kayran, Dmitry; Kewisch, Jorg; Kneisel, Peter; Koop, Ivan; Lambiase, Robert; Litvinenko, Vladimir N; MacKay, William W; Mahler, George; Malitsky, Nikolay; McIntyre, Gary; Meng, Wuzheng; Merminga, Lia; Meshkov, Igor; Mirabella, Kerry; Montag, Christoph; Nagaitsev, Sergei; Nehring, Thomas; Nicoletti, Tony; Oerter, Brian; Parkhomchuk, Vasily; Parzen, George; Pate, David; Phillips, Larry; Preble, Joseph P; Rank, Jim; Rao, Triveni; Rathke, John; Roser, Thomas; Russo, Thomas; Scaduto, Joseph; Schultheiss, Tom; Sekutowicz, Jacek; Shatunov, Yuri; Sidorin, Anatoly O; Skrinsky, Aleksander Nikolayevich; Smirnov, Alexander V; Smith, Kevin T; Todd, Alan M M; Trbojevic, Dejan; Troubnikov, Grigory; Wang, Gang; Wei, Jie; Williams, Neville; Wu, Kuo-Chen; Yakimenko, Vitaly; Zaltsman, Alex; Zhao, Yongxiang; ain, Animesh K

2005-01-01

We report progress on the R&D program for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This electron cooler is designed to cool 100 GeV/nucleon at storage energy using 54 MeV electrons. The electron source will be a superconducting RF photocathode gun. The accelerator will be a superconducting energy recovery linac. The frequency of the accelerator is set at 703.75 MHz. The maximum electron bunch frequency is 9.38 MHz, with bunch charge of 20 nC. The R&D program has the following components: The photoinjector and its photocathode, the superconducting linac cavity, start-to-end beam dynamics with magnetized electrons, electron cooling calculations including benchmarking experiments and development of a large superconducting solenoid. The photoinjector and linac cavity are being incorporated into an energy recovery linac aimed at demonstrating ampere class current at about 20 MeV. A Zeroth Order Design Report is in an advanced draft state, and can be found on the web at http://www.ags...

Linear motor driven Stirling coolers for military and commercial applications

International Nuclear Information System (INIS)

Berry, R.

1992-01-01

This paper discusses the design and performance of a miniature, closed cycle, split stirling, cryogenic cooler that provides 1 watt of cooling at 80 K. The compressor uses two opposed linear motors to drive opposed pistons and the expander uses a pneumatically driven displacer. A single electronics module and compressor has been developed to drive three different expanders that have nominal cold cylinder diameters of 5, 8 and 13 mm

RHIC beam position monitor assemblies

International Nuclear Information System (INIS)

Cameron, P.R.; Grau, M.C.; Ryan, W.A.; Shea, T.J.; Sikora, R.E.

1993-01-01

Design calculations, design details, and fabrication techniques for the RHIC BPM Assemblies are discussed. The 69 mm aperture single plane detectors are 23 cm long short-circuited 50 ohm strip transmission lines subtending 80 degrees. They are mounted on the sextupole end of the Corrector-Quadrupole-Sextupole package and operate at liquid helium temperature. The 69 cm aperture was selected to be the same as that of the beampipe in the CQS package, the 23 cm length is a compromise between mechanical stability and electrical sensitivity to the long low-intensity proton and heavy ion bunches to be found in RHIC during commissioning, and the 80 degree subtended angle maximizes linear aperture. The striplines are aligned after brazing to maintain electrical-to-mechanical centers within 0.1 mm radius, eliminating the need for individual calibration. Because the cryogenic feedthrus isolate the UHV beam vacuum only from the HV insulating vacuum, and do not see liquid helium, a replaceable mini-ConFlat design was chosen to simplify fabrication, calibration, and maintenance

RHIC Beam Position Monitor Assemblies

International Nuclear Information System (INIS)

Cameron, P.R.; Grau, M.C.; Ryan, W.A.; Shea, T.J.; Sikora, R.E.

1993-01-01

Design calculations, design details, and fabrication techniques for the RHIC BPM Assemblies are discussed. The 69 mm aperture single plane detectors are 23 cm long short-circuited 50 ohm strip transmission lines subtending 80 degrees. They are mounted on the sextupole end of the Corrector-Quadrupole-Sextupole package and operate at liquid helium temperature. The 69 cm aperture was selected to be the same as that of the beampipe in the CQS package, dc 23 cm length is a compromise between mechanical stability and electrical sensitivity to the long low-intensity proton and heavy ion bunches to be found in RHIC during commissioning, and the 80 degree subtended angle maximizes linear aperture. The striplines are aligned after brazing to maintain electrical-to-mechanical centers within 0.1 mm radius, eliminating the need for individual calibration. Because the cryogenic feedthrus isolate the UHV beam vacuum only from the HV insulating vacuum, and do not see liquid helium, a replaceable mini-ConFlat design was chosen to simplify fabrication, calibration, and maintenance

Mid Infrared Instrument cooler subsystem test facility overview

Science.gov (United States)

Moore, B.; Zan, J.; Hannah, B.; Chui, T.; Penanen, K.; Weilert, M.

2017-12-01

The Cryocooler for the Mid Infrared Instrument (MIRI) on the James Webb Space Telescope (JWST) provides cooling at 6.2K on the instrument interface. The cooler system design has been incrementally documented in previous publications [1][2][3][4][5]. It has components that traverse three primary thermal regions on JWST: Region 1, approximated by 40K; Region 2, approximated by 100K; and Region 3, which is at the allowable flight temperatures for the spacecraft bus. However, there are several sub-regions that exist in the transition between primary regions and at the heat reject interfaces of the Cooler Compressor Assembly (CCA) and Cooler Control Electronics Assembly (CCEA). The design and performance of the test facility to provide a flight representative thermal environment for acceptance testing and characterization of the complete MIRI cooler subsystem are presented.

Surface tension confined liquid cryogen cooler

Science.gov (United States)

Castles, Stephen H. (Inventor); Schein, Michael E. (Inventor)

1989-01-01

A cryogenic cooler is provided for use in craft such as launch, orbital, and space vehicles subject to substantial vibration, changes in orientation, and weightlessness. The cooler contains a small pore, large free volume, low density material to restrain a cryogen through surface tension effects during launch and zero-g operations and maintains instrumentation within the temperature range of 10 to 140 K. The cooler operation is completely passive, with no inherent vibration or power requirements.

RHIC BEAM ABORT KICKER POWER SUPPLY SYSTEM COMMISSIONING EXPERIENCE AND REMAINING ISSUES

International Nuclear Information System (INIS)

ZHANG, W.; AHRENS, L.A.; MI, J.; OERTER, B.; SANDERS, R.; SANDBERG, J.

2001-01-01

The RHIC Beam Abort Kicker Power Supply Systems commissioning experience and the remaining issues will be reported in this paper. The RHIC Blue Ring Beam Abort Kicker Power Supply System initial commissioning took place in June 1999. Its identical system in Yellow Ring was brought on line during Spring 2000. Each of the RHIC Beam Abort Kicker Power Supply Systems consists of five high voltage modulators and subsystems. These systems are critical devices for RHIC machine protection and environmental protection. They are required to be effective, reliable and operating with sufficient redundancy to safely abort the beam to its beam dump at the end of accumulation or at any time when they are commanded. To deflect 66 GeV ion beam to the beam absorbers, the RHIC Beam Abort Kicker Power Supply Systems were operated at 22 kV level. The RHIC 2000 commissioning run was very successful

BROOKHAVEN: RHIC installation

International Nuclear Information System (INIS)

Anon.

1994-01-01

This summer, the first superconducting magnet was installed in 3.8 kilometre tunnel for Brookhaven's RHIC heavy ion collider (October, page 31). Manufactured by Northrop Grumman's Electronics and System Integration Division, the magnet is the first of RHIC's 373 dipoles. In addition to the dipoles, Northrop Grumman will also provide 432 RHIC quadrupoles. The first quadrupole was delivered on 8 April, a month before the first dipole arrived for onsite testing prior to installation. RHIC will need 1,700 superconducting magnets - dipoles, quadrupoles, sextupoles and correcting magnets, 1,200 of which will be built by industry and the rest built at Brookhaven. The 300 sextupoles are being supplied by Everson Electric

The Liquefaction of Hydrogen and Helium Using Small Coolers

International Nuclear Information System (INIS)

Green, Michael A.

2006-01-01

This report discusses the history of the liquefaction of hydrogen and helium using small coolers. This history dates form the 1960's when two stage GM coolers capable of reaching 7 K were used to liquefy helium and hydrogen by suing an added compressor and J-T circuit. Liquefaction using the added circuit failed to become mainstream because the J-T valve and heat exchanger clogged because of impurities in the gas being liquefied. Liquefaction using a GM cooler without an added J-T circuit proved to be difficult because the first stage was not used to pre-cool the gas coming to the second stage of the cooler. Once the gas being liquefied was pre-cooled using the cooler first stage, improvements in the liquefaction rates were noted. The advent of low temperature pulse tube cooler (down to 2.5 K) permitted one to achieve dramatic improvement is the liquefactions rates for helium. Similar but less dramatic improvements are expected for hydrogen as well. Using the PT-415 cooler, one can expect liquefaction rates of 15 to 20 liters per day for helium or hydrogen provided the heat leak into the cooler and the storage vessel is low. A hydrogen liquefier for MICE is presented at the end of this report

Status of the quadrupoles for RHIC [Relativistic Heavy Ion Collider

International Nuclear Information System (INIS)

Thompson, P.A.; Cottingham, J.G.; Garber, M.

1989-01-01

The proposed Relativistic Heavy Ion Collider (RHIC) will require 408 regular arc quadrupoles. Two full size prototypes have been constructed and tested. The construction uses the single layer, collarless concept which has been successful in the RHIC dipoles. Both the magnets attained short sample current, which is 60% higher than the operating current. This corresponds to a gradient of 113 T/m with clear bore of 80 mm. The preliminary field measurements are in agreement with the calculations, with the exception of an unexpectedly large show sextupole. 2 refs., 5 figs., 1 tab

20 K continuous cycle sorption coolers for the Planck flight mission

Science.gov (United States)

Bhandari, P.; Prina, M.; Bowman, R. C., Jr.; Paine, C.; Pearson, D.; Nash, A.

2003-01-01

In this paper we present the level of maturity of the hydrogen sorption cooler technology at JPL by describing the design and how it has been validated at the subsystem and system levels. In addition, we will describe how such systems could be advantageously used for other space missions with similar needs and cooler attributes.

The RHIC status update

International Nuclear Information System (INIS)

Ozaki, S.

1995-01-01

The construction of the Relativistic Heavy Ion Collider (RHIC) began in 1991, with the completion date originally scheduled for 1997. Significant reduction of the funding levels in FY 1993 and 1994, and the funding level cap for FY 1995 and later years caused a 19-month stretchout of the construction period to the second quarter of FY 1999, and an increase of the total estimated cost (TEC) to $475 M. The Project, therefore, is now at the halfway mark of the construction period with actual cost and schedule performance tracking close to the DOE-approved baseline. Construction funding through FY 1994 reached close to 60% of the TEC. Incidentally, if one adds the current value of preexisting facilities which will be incorporated into RHIC, such as the injection system (Tandem Van de Graaff - the Booster - the AGS), the esixting 3.8 km tunnel, the 24 kW helium refrigerator, etc., the total value of the RHIC facility, when completed, will reach one billion dollars, if not more. The accelerator lattice design was finalized in 1992 after an intensive study was made to optimize the collider design for performance, operational flexibility, and value engineering. The civil construciton, including the collider enclosure, magnet access ports to the ring tunnel, and six service buildings for accelerator power supplies and cryogenic control boxes was completed

Illuminating RHIC matter with the multi-purpose direct photon

International Nuclear Information System (INIS)

Frantz, Justin

2007-01-01

In the RHIC era, the use of direct photon physics to probe heavy ion collisions has developed beyond its original scope. I make evaluations of the current state of several measurements by RHIC experiments and their associated physics implications, with a focus on their current and desired precision. At low p T , thermal photon theory is still not well constrained by the data, but improvements are on the way. At higher p T , we have been able to gain important insights, now with regards to the proposed 'jet-medium' photon sources (Fries, Muller and Srivastava 2003 Phys. Rev. Lett. 90 132301 (Preprint nucl-th/0208001); Zakharov 2004 JETP Lett. 80 617). Such predictions, as they currently exist, seem to be disfavoured by the PHENIX data; however, the idea is probably not ruled out. Finally, direct γ-jet correlations have been measured for the first time at RHIC and already show hints of medium modification

THE RHIC INJECTION SYSTEM.

Energy Technology Data Exchange (ETDEWEB)

FISCHER,W.; GLENN,J.W.; MACKAY,W.W.; PTITSIN,V.; ROBINSON,T.G.; TSOUPAS,N.

1999-03-29

The RHIC injection system has to transport beam from the AGS-to-RHIC transfer line onto the closed orbits of the RHIC Blue and Yellow rings. This task can be divided into three problems. First, the beam has to be injected into either ring. Second, once injected the beam needs to be transported around the ring for one turn. Third, the orbit must be closed and coherent beam oscillations around the closed orbit should be minimized. We describe our solutions for these problems and report on system tests conducted during the RHIC Sextant test performed in 1997. The system will be fully commissioned in 1999.

Iron saturation control in RHIC dipole magnets

International Nuclear Information System (INIS)

Thompson, P.A.; Gupta, R.C.; Kahn, S.A.; Hahn, H.; Morgan, G.H.; Wanderer, P.J.; Willen, E.

1991-01-01

The Relativistic Heavy Ion Collider (RHIC) will require 360 dipoles of 80 mm bore. This paper discusses the field perturbations produced by the saturation of the yoke iron. Changes have been made to the yoke to reduce these perturbations, in particular, decapole -4 . Measurements and calculations for 6 series of dipole magnets are presented. 2 refs., 2 figs., 1 tab

Polarized Proton Collisions at RHIC

CERN Document Server

Bai, Mei; Alekseev, Igor G; Alessi, James; Beebe-Wang, Joanne; Blaskiewicz, Michael; Bravar, Alessandro; Brennan, Joseph M; Bruno, Donald; Bunce, Gerry; Butler, John J; Cameron, Peter; Connolly, Roger; De Long, Joseph; Drees, Angelika; Fischer, Wolfram; Ganetis, George; Gardner, Chris J; Glenn, Joseph; Hayes, Thomas; Hseuh Hsiao Chaun; Huang, Haixin; Ingrassia, Peter; Iriso, Ubaldo; Laster, Jonathan S; Lee, Roger C; Luccio, Alfredo U; Luo, Yun; MacKay, William W; Makdisi, Yousef; Marr, Gregory J; Marusic, Al; McIntyre, Gary; Michnoff, Robert; Montag, Christoph; Morris, John; Nicoletti, Tony; Oddo, Peter; Oerter, Brian; Osamu, Jinnouchi; Pilat, Fulvia Caterina; Ptitsyn, Vadim; Roser, Thomas; Satogata, Todd; Smith, Kevin T; Svirida, Dima; Tepikian, Steven; Tomas, Rogelio; Trbojevic, Dejan; Tsoupas, Nicholaos; Tuozzolo, Joseph; Vetter, Kurt; Wilinski, Michelle; Zaltsman, Alex; Zelenski, Anatoli; Zeno, Keith; Zhang, S Y

2005-01-01

The Relativistic Heavy Ion Collider~(RHIC) provides not only collisions of ions but also collisions of polarized protons. In a circular accelerator, the polarization of polarized proton beam can be partially or fully lost when a spin depolarizing resonance is encountered. To preserve the beam polarization during acceleration, two full Siberian snakes were employed in RHIC to avoid depolarizing resonances. In 2003, polarized proton beams were accelerated to 100~GeV and collided in RHIC. Beams were brought into collisions with longitudinal polarization at the experiments STAR and PHENIX by using spin rotators. RHIC polarized proton run experience demonstrates that optimizing polarization transmission efficiency and improving luminosity performance are significant challenges. Currently, the luminosity lifetime in RHIC is limited by the beam-beam effect. The current state of RHIC polarized proton program, including its dedicated physics run in 2005 and efforts to optimize luminosity production in beam-beam limite...

RHIC Data Correlation Methodology

International Nuclear Information System (INIS)

Michnoff, R.; D'Ottavio, T.; Hoff, L.; MacKay, W.; Satogata, T.

1999-01-01

A requirement for RHIC data plotting software and physics analysis is the correlation of data from all accelerator data gathering systems. Data correlation provides the capability for a user to request a plot of multiple data channels vs. time, and to make meaningful time-correlated data comparisons. The task of data correlation for RHIC requires careful consideration because data acquisition triggers are generated from various asynchronous sources including events from the RHIC Event Link, events from the two Beam Sync Links, and other unrelated clocks. In order to correlate data from asynchronous acquisition systems a common time reference is required. The RHIC data correlation methodology will allow all RHIC data to be converted to a common wall clock time, while still preserving native acquisition trigger information. A data correlation task force team, composed of the authors of this paper, has been formed to develop data correlation design details and provide guidelines for software developers. The overall data correlation methodology will be presented in this paper

Polarized proton collider at RHIC

International Nuclear Information System (INIS)

Alekseev, I.; Allgower, C.; Bai, M.; Batygin, Y.; Bozano, L.; Brown, K.; Bunce, G.; Cameron, P.; Courant, E.; Erin, S.; Escallier, J.; Fischer, W.; Gupta, R.; Hatanaka, K.; Huang, H.; Imai, K.; Ishihara, M.; Jain, A.; Lehrach, A.; Kanavets, V.; Katayama, T.; Kawaguchi, T.; Kelly, E.; Kurita, K.; Lee, S.Y.; Luccio, A.; MacKay, W.W.; Mahler, G.; Makdisi, Y.; Mariam, F.; McGahern, W.; Morgan, G.; Muratore, J.; Okamura, M.; Peggs, S.; Pilat, F.; Ptitsin, V.; Ratner, L.; Roser, T.; Saito, N.; Satoh, H.; Shatunov, Y.; Spinka, H.; Syphers, M.; Tepikian, S.; Tominaka, T.; Tsoupas, N.; Underwood, D.; Vasiliev, A.; Wanderer, P.; Willen, E.; Wu, H.; Yokosawa, A.; Zelenski, A.N.

2003-01-01

In addition to heavy ion collisions (RHIC Design Manual, Brookhaven National Laboratory), RHIC will also collide intense beams of polarized protons (I. Alekseev, et al., Design Manual Polarized Proton Collider at RHIC, Brookhaven National Laboratory, 1998, reaching transverse energies where the protons scatter as beams of polarized quarks and gluons. The study of high energy polarized protons beams has been a long term part of the program at BNL with the development of polarized beams in the Booster and AGS rings for fixed target experiments. We have extended this capability to the RHIC machine. In this paper we describe the design and methods for achieving collisions of both longitudinal and transverse polarized protons in RHIC at energies up to √s=500 GeV

Design of a large heat lift 40 K to 80 K pulse tube cryocooler for space applications

NARCIS (Netherlands)

Trollier, T.; Tanchon, J.; Buquet, J.; Ravex, A.; Charles, I.; Coynel, A.; Duband, L.; Ercolani, E.; Guillemet, L.; Mullié, J.; Dam, J.A.M.; Benschop, T.; Linder, M.; Miller, S.D.; Ross, Jr. R.G.

2007-01-01

A Large heat lift Pulse Tube Cooler (LPTC) is under development in partnership with AL/ DTA, CEA/SBT and THALES Cryogenics. The engineering model is expected to provide 2.3 W at 50 K at a 10 °C rejection temperature and 160 watts of electrical input power to the compressor. The split coaxial design

Thermoluminescence in alkali halides irradiated at 80K; Termoluminiscencia en haluros alcalinos irradiados a 80K

Energy Technology Data Exchange (ETDEWEB)

Jimenez de Castro, M

1978-07-01

The thermoluminescence, the thermally stimulated currents and the thermal stability of the F centres induced in pure NaCl and KC1 crystals by X irradiation at 80K have been studied in detail, In the range between 80 and 300K. The thermoluminescent processes induced by illumination at 80K with F light in samples previously irradiated at room temperature has also been studied. It has been clearly observed the existence of thermoluminescent processes due to electrons and holes thermally released from traps, in which the F centres are not involved. The existence of hole-F centre recombination has not been observed. There are several thermoluminescent processes in both materials which are scribed to the recombination of F centres with mobile interstitial halogen atoms thermally released from traps, which are likely monovalent impurities in this temperature interval. The light emitting stage in these processes is originated by the formation of self trapped excitons. (Author) 66 refs.

The Cooling of a Liquid Absorber using a Small Cooler

International Nuclear Information System (INIS)

Baynham, D.E.; Bradshaw, T.W.; Green, M.A.; Ishimoto, S.; Liggins, N.

2005-01-01

This report discusses the use of small cryogenic coolers for cooling the Muon Ionization Cooling Experiment (MICE) liquid cryogen absorbers. Since the absorber must be able contain liquid helium as well liquid hydrogen, the characteristics of the available 4.2 K coolers are used here. The issues associated with connecting two-stage coolers to liquid absorbers are discussed. The projected heat flows into an absorber and the cool-down of the absorbers using the cooler are presented. The warm-up of the absorber is discussed. Special hydrogen safety issues that may result from the use of a cooler on the absorbers are also discussed

Spin Physics at RHIC

International Nuclear Information System (INIS)

Bland, L.C.

2003-01-01

The physics goals that will be addressed by colliding polarized protons at the Relativistic Heavy Ion Collider (RHIC) are described. The RHIC spin program provides a new generation of experiments that will unfold the quark, anti-quark and gluon contributions to the proton's spin. In addition to these longer term goals, this paper describes what was learned from the first polarized proton collisions at √(s)=200 GeV. These collisions took place in a five-week run during the second year of RHIC operation

Fast Automated Decoupling at RHIC

CERN Document Server

Beebe-Wang, Joanne

2005-01-01

Coupling correction is essential for the operational performance of RHIC. The independence of the transverse degrees of freedom makes diagnostics and tune control easier, and it is advantageous to operate an accelerator close to the coupling resonance to minimize nearby nonlinear sidebands. An automated decoupling application has been developed at RHIC for coupling correction during routine operations. The application decouples RHIC globally by minimizing the tune separation through finding the optimal settings of two orthogonal skew quadrupole families. The program provides options of automatic, semi-automatic and manual decoupling operations. It accesses tune information from all RHIC tune measurement systems: the PLL (Phase Lock Loop), the high frequency Schottky system, and the tune meter. It also supplies tune and skew quadrupole scans, finding the minimum tune separation, display the real time results and interface with the RHIC control system. We summarize the capabilities of the decoupling application...

Helium release rates and ODH calculations from RHIC magnet cooling line failure

Energy Technology Data Exchange (ETDEWEB)

Liaw, C.J.; Than, Y.; Tuozzolo, J.

2011-03-28

A catastrophic failure of the magnet cooling lines, similar to the LHC superconducting bus failure incident, could discharge cold helium into the RHIC tunnel and cause an Oxygen Deficiency Hazard (ODH) problem. A SINDA/FLUINT{reg_sign} model, which simulated the 4.5K/4 atm helium flowing through the magnet cooling system distribution lines, then through a line break into the insulating vacuum volumes and discharging via the reliefs into the RHIC tunnel, had been developed. Arc flash energy deposition and heat load from the ambient temperature cryostat surfaces are included in the simulations. Three typical areas: the sextant arc, the Triplet/DX/D0 magnets, and the injection area, had been analyzed. Results, including helium discharge rates, helium inventory loss, and the resulting oxygen concentration in the RHIC tunnel area, are reported. Good agreement had been achieved when comparing the simulation results, a RHIC sector depressurization test measurement, and some simple analytical calculations.

FAST AUTOMATED DECOUPLING AT RHIC

International Nuclear Information System (INIS)

BEEBE-WANG, J.J.

2005-01-01

Coupling correction is essential for the operational performance of RHIC. The independence of the transverse degrees of freedom makes diagnostics and tune control easier, and it is advantageous to operate an accelerator close to the coupling resonance to minimize nearby nonlinear sidebands. An automated coupling correction application iDQmini has been developed for RHIC routine operations. The application decouples RHIC globally by minimizing the tune separation through finding the optimal settings of two orthogonal skew quadrupole families. The program iDQmini provides options of automatic, semi-automatic and manual decoupling operations. It accesses tune information from all RHIC tune measurement systems: the PLL (phase lock loop), the high frequency Schottky system and the tune meter. It also supplies tune and skew quadrupole scans, finding the minimum tune separation, display the real time results and interface with the RHIC control system. We summarize the capabilities of the coupling correction application iDQmini, and discuss the operational protections incorporated in the program

High luminosity electron-hadron collider eRHIC

Energy Technology Data Exchange (ETDEWEB)

Ptitsyn, V.; Aschenauer, E.; Bai, M.; Beebe-Wang, J.; Belomestnykh, S.; Ben-Zvi, I.; Blaskiewicz, M..; Calaga, R.; Chang, X.; Fedotov, A.; Gassner, D.; Hammons, L.; Hahn, H.; Hammons, L.; He, P.; Hao, Y.; Jackson, W.; Jain, A.; Johnson, E.C.; Kayran, D.; Kewisch, J.; Litvinenko, V.N.; Luo, Y.; Mahler, G.; McIntyre, G.; Meng, W.; Minty, M.; Parker, B.; Pikin, A.; Rao, T.; Roser, T.; Skaritka, J.; Sheehy, B.; Skaritka, J.; Tepikian, S.; Than, Y.; Trbojevic, D.; Tsoupas, N.; Tuozzolo, J.; Wang, G.; Webb, S.; Wu, Q.; Xu, W.; Pozdeyev, E.; Tsentalovich, E.

2011-03-28

We present the design of a future high-energy high-luminosity electron-hadron collider at RHIC called eRHIC. We plan on adding 20 (potentially 30) GeV energy recovery linacs to accelerate and to collide polarized and unpolarized electrons with hadrons in RHIC. The center-of-mass energy of eRHIC will range from 30 to 200 GeV. The luminosity exceeding 10{sup 34} cm{sup -2} s{sup -1} can be achieved in eRHIC using the low-beta interaction region with a 10 mrad crab crossing. We report on the progress of important eRHIC R&D such as the high-current polarized electron source, the coherent electron cooling, ERL test facility and the compact magnets for recirculation passes. A natural staging scenario of step-by-step increases of the electron beam energy by building-up of eRHIC's SRF linacs is presented.

Prospects for polarization at RHIC and SSC

International Nuclear Information System (INIS)

Lee, S.Y.

1991-01-01

In low to medium energy accelerators, betatron tune jumps and vertical orbit harmonic correction methods have been used to overcome the intrinsic and imperfection resonances. At high energy accelerators, snakes are needed to preserve polarization. We analyze the effects of snake resonances, snake imperfections overlapping resonances on the spin depolarization. We discuss also results of recent snake experiments at the IUCF Cooler Ring. The snake can overcome various kinds of spin depolarization resonances. These experiments pointed out further that partial snake can be used to cure the imperfection resonances in low to medium energy accelerators. We also examine various snake designs. A new generalized snake concept allows for two possible configurations. The compact configuration offers the advantages of shorter total snake length and smaller horizontal orbit displacement. The split snake configuration allows for dual functions of a snake and a 90 degree spin rotator at the mid-section of the snake, which provides helicity state collisions. The requirements for obtaining high luminosity polarized protons at high energy colliders, such as RHIC and SSC, are reviewed

Linear beam dynamics and ampere class superconducting RF cavities at RHIC

Science.gov (United States)

Calaga, Rama R.

The Relativistic Heavy Ion Collider (RHIC) is a hadron collider designed to collide a range of ions from protons to gold. RHIC operations began in 2000 and has successfully completed five physics runs with several species including gold, deuteron, copper, and polarized protons. Linear optics and coupling are fundamental issues affecting the collider performance. Measurement and correction of optics and coupling are important to maximize the luminosity and sustain stable operation. A numerical approach, first developed at SLAC, was implemented to measure linear optics from coherent betatron oscillations generated by ac dipoles and recorded at multiple beam position monitors (BPMs) distributed around the collider. The approach is extended to a fully coupled 2D case and equivalence relationships between Hamiltonian and matrix formalisms are derived. Detailed measurements of the transverse coupling terms are carried out at RHIC and correction strategies are applied to compensate coupling both locally and globally. A statistical approach to determine BPM reliability and performance over the past three runs and future improvements also discussed. Aiming at a ten-fold increase in the average heavy-ion luminosity, electron cooling is the enabling technology for the next luminosity upgrade (RHIC II). Cooling gold ion beams at 100 GeV/nucleon requires an electron beam of approximately 54 MeV and a high average current in the range of 50-200 mA. All existing e-Coolers are based on low energy DC accelerators. The only viable option to generate high current, high energy, low emittance CW electron beam is through a superconducting energy-recovery linac (SC-ERL). In this option, an electron beam from a superconducting injector gun is accelerated using a high gradient (˜ 20 MV/m) superconducting RF (SRF) cavity. The electrons are returned back to the cavity with a 180° phase shift to recover the energy back into the cavity before being dumped. A design and development of a half

Brookhaven: RHIC magnets

International Nuclear Information System (INIS)

Heppelman, Steve

1990-01-01

Last year, Brookhaven's proposal for a Relativistic Heavy Ion Collider - RHIC - was scrutinized by the US Department of Energy and deemed to be ready for construction funding. The hope is that the money will be voted soon so that construction can get underway at the start of the new US financial year in October. The 3.8 kilometre RHIC tunnel was completed ten years ago for the doomed Isabelle/CBA proton collider project

Re-Condensation and Liquefaction of Helium and Hydrogen Using Coolers

International Nuclear Information System (INIS)

Green, Michael A.

2009-01-01

Coolers are used to cool cryogen free devices at temperatures from 5 to 30 K. Cryogen free cooling involves a temperature drop within the device being cooled and between the device and the cooler cold heads. Liquid cooling with a liquid cryogen distributed over the surface of a device combined with re-condensation can result in a much lower temperature drop between the cooler and the device being cooled. The next logical step beyond simple re-condensation is using a cooler to liquefy the liquid cryogen in the device. A number of tests of helium liquefaction and re-condensation of helium have been run using a pulse tube cooler in the drop-in mode. This report discusses the parameter space over which re-condensation and liquefaction for helium and hydrogen can occur.

DESIGN ISSUES FOR THE RHIC EBIS

International Nuclear Information System (INIS)

Beebe, E.; Alessi, J.; Kponou, A.; Pikin, A.; Prelec, K.; Kuznetzov, G.; Tiunov, M.

2000-01-01

Promising results are currently being obtained on the BNL Electron Beam Test Stand (EBTS), which is a prototype for the Relativistic Heavy Ion Collider (RHIC) EBIS. Based on the present-results, a proposal has been made regarding the general design of the RHIC EBIS. During the next year experiments will be made to investigate physics issues and beam properties important to the detailed design of the RHIC EBIS. Below we have outlined some of the physics issues to be explored experimentally, beam diagnostics that will be employed, and hardware modifications that are desired to go from the prototype stage to the RHIC EBIS

Consideration of Relativistic Dynamics in High-Energy Electron Coolers

CERN Document Server

Bruhwiler, David L

2005-01-01

A proposed electron cooler for RHIC would use ~55 MeV electrons to cool fully-ionized 100 GeV/nucleon gold ions.* At two locations in the collider ring, the electrons and ions will co-propagate for ~13 m, with velocities close to c and gamma>100. To lowest-order, one can Lorentz transform all physical quantities into the beam frame and calculate the dynamical friction forces assuming a nonrelativisitc, electrostatic plasma. However, we show that nonlinear space charge forces of the bunched electron beam on the ions must be calculated relativistically, because an electrostatic beam-frame calculation is not valid for such short interaction times. The validity of nonrelativistic friction force calculations must also be considered. Further, the transverse thermal velocities of the high-charge (~20 nC) electron bunch are large enough that some electrons have marginally relativistic velocities, even in the beam frame. Hence, we consider relativistic binary collisions – treating the model problem of ...

40 CFR 61.134 - Standard: Naphthalene processing, final coolers, and final-cooler cooling towers.

Science.gov (United States)

2010-07-01

... coolers, and final-cooler cooling towers. 61.134 Section 61.134 Protection of Environment ENVIRONMENTAL... Standard: Naphthalene processing, final coolers, and final-cooler cooling towers. (a) No (“zero”) emissions are allowed from naphthalene processing, final coolers and final-cooler cooling towers at coke by...

The RHIC injection fast kicker

International Nuclear Information System (INIS)

Forsyth, E.B.; Pappas, G.C.; Tuozzolo, J.E.; Zhang, W.

1995-01-01

The purpose of the injection kicker is to provide the ultimate deflection to the incoming beam from the Alternating Gradient Synchrotron (AGS) into the Relativistic Heavy Ion Collider (RHIC). The beam is kicked in the vertical direction to place it on the equilibrium orbit of RHIC. Each bunch in the AGS is transferred separately, and stacked box-car fashion in the appropriate RHIC rf bucket. In order to achieve the required deflection angle four magnets powered by four pulsers will be used for each ring of RHIC. When the bunches are stacked in RHIC the last few rf buckets are left unfilled in order to provide a gap in the beam to facilitate the ejection or beam abort process. This also means there is not a severe constraint on the fall-time of the injection kicker. One prototype pulser has been built and tested. Much of the development effort has gone into the magnet design. Although lumped ferrite magnets are simpler to build and require less power to reach full field, a transmission line magnet was developed because of the very fast rise-time requirement and the tolerances imposed on the field variation and ripple

RHIC STATUS AND PLANS.

Energy Technology Data Exchange (ETDEWEB)

PILAT,R.

2002-06-02

RHIC ended successfully its second year of operation in January 2002 after a six month run with gold ions and two months of polarized proton collisions. I will review the machine performance and accomplishments, that include reaching design energy (100 GeV/u) and design luminosity during the gold run, and the first high energy (100 GeV) polarized proton collisions. I will also discuss the machine development strategy and the main performance milestones. The goals and plans for the shutdown and the nest run, scheduled to start in November 2002 have been the focus of a RHIC Retreat in March 2002. I will summarize findings and plans for the upcoming run and outline a vision for the nest few years of RHIC operation and upgrades.

Oxide-cathode activation and surface temperature calculation of electron cooler

International Nuclear Information System (INIS)

Li Jie; Yang Xiaodong; Mao Lijun; Li Guohong; Yuan Youjin; Liu Zhanwen; Zhang Junhui; Yang Xiaotian; Ma Xiaoming; Yan Tailai

2011-01-01

The pollution on electron gun ceramic insulation of electron cooler restricted the operation of electron cooler at HIRFL-CSR main ring. To cool and accumulate ion beam well, the pollution was cleared and a new oxide-coated cathode was assembled. The processes of cathode replacement,vacuum chamber baking-out, and thermal decomposition of coating binders and alkaline earth metal carbonates, and cathode activation are presented. The electron gun perveance of 10.6 μA/V 1.5 was attained under the heating power of 60 W. The typical surface temperature of oxide-coated cathode that is calculated through grey-body radiation is 1 108 K which shows a comparable result to the experimental measurement 1 078 K. The perveance growth of electron gun during the electron cooler operation is also explained by partial activation of the cathode. (authors)

Comparison of image quality between 70 kVp and 80 kVp: application to paediatric cardiac CT

Energy Technology Data Exchange (ETDEWEB)

Durand, Sebastien [Centre Chirurgical Marie Lannelongue, Radiology Department, Le Plessis-Robinson (France); Paul, Jean-Francois [Institut Mutualiste Montsouris, Radiology Department, Paris (France)

2014-12-15

To evaluate noise level and contrast-to-noise ratio (CNR) with various kVp-mAs pairs producing the same computed tomography dose index (CTDI) value. The 80 kVp and new 70-kVp settings were compared. The noise was measured in 10 ovoid water phantoms with different diameters from 10 cm to 28 cm. Contrast was obtained from CTs of iodine-filled tubes. Spiral acquisition protocols at 70 kVp and 80 kVp, with the same CTDI, were applied. In the clinical study, two matched groups, each of 21 paediatric patients, underwent 70-kVp or 80-kVp ECG-gated iodinated-enhanced sequential CT. Noise was significantly higher with 70 kVp than 80-kVp settings for all phantom sizes. Estimated CNR with phantoms was higher at 70 kVp than 80 kVp, and the difference decreased from 17 % to 3 % as phantom size increased. The mean CNR in paediatric patients was 15.2 at 70 kVp and 14.3 at 80 kVp (ns). The CNR difference was significantly larger in the small-child subgroup. Noise level is slightly higher at the 70-kVp than the 80-kVp setting, but the CNR is higher, particularly for small children. Therefore, 70 kVp may be appropriate for contrast-enhanced CT examinations and 80 kVp for non-enhanced CT in small children. (orig.)

High-energy high-luminosity electron-ion collider eRHIC

International Nuclear Information System (INIS)

Litvinenko, V.N.; Ben-Zvi, I.; Hammons, L.; Hao, Y.; Webb, S.

2011-01-01

In this paper, we describe a future electron-ion collider (EIC), based on the existing Relativistic Heavy Ion Collider (RHIC) hadron facility, with two intersecting superconducting rings, each 3.8 km in circumference. The replacement cost of the RHIC facility is about two billion US dollars, and the eRHIC will fully take advantage and utilize this investment. We plan adding a polarized 5-30 GeV electron beam to collide with variety of species in the existing RHIC accelerator complex, from polarized protons with a top energy of 325 GeV, to heavy fully-striped ions with energies up to 130 GeV/u. Brookhaven's innovative design, is based on one of the RHIC's hadron rings and a multi-pass energy-recovery linac (ERL). Using the ERL as the electron accelerator assures high luminosity in the 10 33 -10 34 cm -2 sec -1 range, and for the natural staging of eRHIC, with the ERL located inside the RHIC tunnel. The eRHIC will provide electron-hadron collisions in up to three interaction regions. We detail the eRHIC's performance in Section 2. Since first paper on eRHIC paper in 2000, its design underwent several iterations. Initially, the main eRHIC option (the so-called ring-ring, RR, design) was based on an electron ring, with the linac-ring (LR) option as a backup. In 2004, we published the detailed 'eRHIC 0th Order Design Report' including a cost-estimate for the RR design. After detailed studies, we found that an LR eRHIC has about a 10-fold higher luminosity than the RR. Since 2007, the LR, with its natural staging strategy and full transparency for polarized electrons, became the main choice for eRHIC. In 2009, we completed technical studies of the design and dynamics for MeRHIC with 3-pass 4 GeV ERL. We learned much from this evaluation, completed a bottom-up cost estimate for this $350M machine, but then shelved the design. In the same year, we turned again to considering the cost-effective, all-in-tunnel six-pass ERL for our design of the high-luminosity eRHIC. In it

RESEARCH PLAN FOR SPIN PHYSICS AT RHIC.

Energy Technology Data Exchange (ETDEWEB)

AIDALA, C.; BUNCE, G.; ET AL.

2005-02-01

In this report we present the research plan for the RHIC spin program. The report covers (1) the science of the RHIC spin program in a world-wide context; (2) the collider performance requirements for the RHIC spin program; (3) the detector upgrades required, including timelines; (4) time evolution of the spin program.

Thermal performance of various multilayer insulation systems below 80K

International Nuclear Information System (INIS)

Boroski, W.N.; Nicol, T.H.; Schoo, C.J.

1992-04-01

The SSC collider dipole cryostat consists of a vacuum shell operating at room temperature, two thermal shields operating near 80K and 20K respectively, and the superconducting magnet assembly operating near 4K. The cryostat design incorporates multilayer insulation (MLI) blankets to limit radiant heat transfer into the 80K and 20K thermal shields. Also, an MLI blanket is used to impede heat transfer through residual gas conduction into the 4K superconducting magnet assembly. A measurement facility at Fermilab has been used to experimentally optimize the thermal insulation system for the dipole cryostat. Previous thermal measurements have been used to define the 80K MLI system configuration and verify system performance. With the 80K MLI system defined, the current effort has focused on experimentally defining the optimum insulation scheme for the 20K thermal shield. The SSC design specification requires that radiant heat transfer be limited to 0.093 W/m 2 at an insulating vacuum of 10 -6 torr

The heavy ion injection scheme for RHIC [Relativistic Heavy Ion Collider

International Nuclear Information System (INIS)

Rhoades-Brown, M.J.

1989-01-01

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven has a multi-component injection system. The Collider requires very heavy ions such as 79 197 Au to be injected fully stripped of atomic electrons, at a kinetic energy of approximately 10 GeV/nucleon. However, the heavy ions are produced initially at a negative ion source and accelerated first in a 15 MV Tandem. These partially stripped ions have a kinetic energy of approximately 1 MeV/nucleon on leaving the Tandem. In order to achieve the injection requirements for RHIC, the partially stripped ions are accelerated in the Booster (currently under construction) and pass through a stripping foil on their way to the Alternating Gradient Synchrotron (AGS), where they are further accelerated before injection into RHIC. Recent theoretical calculations have shown quite convincingly that very heavy ions with 2 electrons in the filled K-shell may be accelerated with negligible loss in the AGS. 13 refs., 3 figs., 3 tabs

Prospects for spin physics at RHIC

International Nuclear Information System (INIS)

Robinett, R.W.; Pennsylvania State Univ., University Park, PA

1995-06-01

The proposal to perform polarized proton-proton collisions at collider energies at RHIC is reviewed. After a brief reminder of the desirability of high energy spin physics measurements, we discuss the machine parameters and detector features which are taken to define a program of spin physics at RHIC. Some of the many physics processes which can provide information on polarized parton distributions and the spin-dependence of QCD and the electroweak model at RHIC energies are discussed

RHIC Sextant Test -- Physics and performance

International Nuclear Information System (INIS)

Wei, J.; Fischer, W.; Ahrens, L.

1997-01-01

This paper presents beam physics and machine performance results of the Relativistic Heavy Ion Collider (RHIC) Sextant and AGS-to-RHIC (AtR) transfer line during the Sextant Test in early 1997. Techniques used to measure both machine properties (difference orbits, dispersion, and beamline optics) and beam parameters (energy, intensity, transverse and longitudinal emittances) are described. Good agreement was achieved between measured and design lattice optics. The gold ion beam quality was shown to approach RHIC design requirements

Brookhaven: Ready for RHIC

International Nuclear Information System (INIS)

Ludlam, Tom

1990-01-01

With its RHIC - Relativistic Heavy Ion Collider - project now part of the budget proposed by US President Bush for fiscal year 1991, Brookhaven is about to start construction of a unique kind of high energy collider. At a time when accelerators handling particles - electrons, protons and their antimatter counterparts - are boosting beam energies for microscopes to probe evershorter distances, RHIC is envisioned as a great pressure-cooker for strongly interacting matter

Brookhaven: Ready for RHIC

Energy Technology Data Exchange (ETDEWEB)

Ludlam, Tom

1990-04-15

With its RHIC - Relativistic Heavy Ion Collider - project now part of the budget proposed by US President Bush for fiscal year 1991, Brookhaven is about to start construction of a unique kind of high energy collider. At a time when accelerators handling particles - electrons, protons and their antimatter counterparts - are boosting beam energies for microscopes to probe evershorter distances, RHIC is envisioned as a great pressure-cooker for strongly interacting matter.

Joining the RHIC Online and Offline Models

CERN Document Server

Malitsky, Nikolay; Fedotov, Alexei V; Kewisch, Jorg; Luccio, Alfredo U; Pilat, Fulvia Caterina; Ptitsyn, Vadim; Satogata, Todd; Talman, Richard M; Tepikian, Steven; Wei, Jie

2005-01-01

The paper presents an interface encompassing the RHIC online ramp model and the UAL offline simulation framework. The resulting consolidated facility aims to minimize the gap between design and operational data, and to facilitate analysis of RHIC performance and future upgrades in an operational context. The interface is based on the Accelerator Description Exchange Format (ADXF), and represents a snapshot of the RHIC online model which is in turn driven by machine setpoints. This approach is also considered as an intermediate step towards integrating the AGS and RHIC modeling environments to produce a unified online and offline AGS model for operations.

RHIC spin program

International Nuclear Information System (INIS)

Bunce, G.

1995-01-01

Colliding beams of high energy polarized protons at RHIC is an excellent way to probe the polarization of gluons, u and d quarks in a polarized proton. RHIC is the Relativistic Heavy Ion Collider being built now at Brookhaven in the ISABELLE tunnel. It is designed to collide gold ions on gold ions at 100 GeV/nucleon. Its goal is to discover the quark-gluon plasma, and the first collisions are expected in March, 1999. RHIC will also make an ideal polarized proton collider with high luminosity and 250 GeV x 250 GeV collisions. The RHIC spin physics program is: (1) Use well-understood perturbative QCD probes to study non-perturbative confining dynamics in QCD. We will measure - gluon and sea quark polarization in a polarized proton, polarization of quarks in a transversely polarized proton. (2) Look for additional surprises using the first high energy polarized proton collider. We will - look for the expected maximal parity violation in W and Z boson production, - search for parity violation in other processes, - test parton models with spin. This lecture is organized around a few of the key ideas: Siberian Snakes--What are they? High energy proton-proton collisions are scatters of quarks and leptons, at high x, a polarized proton beam is a beam of polarized u quarks, quark and gluon collisions are very sensitive to spin. We will discuss two reactions: how direct photon production measures gluon polarization, and how W + boson production measures u and d quark polarization

RHIC spin program

Energy Technology Data Exchange (ETDEWEB)

Bunce, G.

1995-12-31

Colliding beams of high energy polarized protons at RHIC is an excellent way to probe the polarization of gluons, u and d quarks in a polarized proton. RHIC is the Relativistic Heavy Ion Collider being built now at Brookhaven in the ISABELLE tunnel. It is designed to collide gold ions on gold ions at 100 GeV/nucleon. Its goal is to discover the quark-gluon plasma, and the first collisions are expected in March, 1999. RHIC will also make an ideal polarized proton collider with high luminosity and 250 GeV x 250 GeV collisions. The RHIC spin physics program is: (1) Use well-understood perturbative QCD probes to study non-perturbative confining dynamics in QCD. We will measure - gluon and sea quark polarization in a polarized proton, polarization of quarks in a transversely polarized proton. (2) Look for additional surprises using the first high energy polarized proton collider. We will - look for the expected maximal parity violation in W and Z boson production, - search for parity violation in other processes, - test parton models with spin. This lecture is organized around a few of the key ideas: Siberian Snakes--What are they? High energy proton-proton collisions are scatters of quarks and leptons, at high x, a polarized proton beam is a beam of polarized u quarks, quark and gluon collisions are very sensitive to spin. We will discuss two reactions: how direct photon production measures gluon polarization, and how W{sup +} boson production measures u and d quark polarization.

Analysis of RHIC beam dump pre-fires

International Nuclear Information System (INIS)

Zhang, W.; Ahrens, L.; Fischer, W.; Hahn, H.; Mi, J.; Sandberg, J.; Tan, Y.

2011-01-01

It has been speculated that the beam may cause instability of the RHIC Beam Abort Kickers. In this study, we explore the available data of past beam operations, the device history of key modulator components, and the radiation patterns to examine the correlations. The RHIC beam abort kicker system was designed and built in the 90's. Over last decade, we have made many improvements to bring the RHIC beam abort kicker system to a stable operational state. However, the challenge continues. We present the analysis of the pre-fire, an unrequested discharge of kicker, issues which relates to the RHIC machine safety and operational stability.

Physics with tagged forward protons at RHIC

Energy Technology Data Exchange (ETDEWEB)

Yip,K.

2009-08-30

The physics reach of the STAR detector at RHIC has been extended to include elastic and inelastic diffraction measurements with tagged forward protons. This program has started at RHIC in p+p collisions with a special optics run of {beta}* {approx} 21 m at STAR, at the center-of-mass energy {radical}s = 200 GeV during the last week of the RHIC 2009 run.

Nitrosyl hemoglobins: EPR above 80 K

Energy Technology Data Exchange (ETDEWEB)

Wajnberg, E.; Bemski, G.; El-Jaick, L.J.; Alves, O.C.

1995-03-01

The EPR spectra of nitrosyl hemoglobin and myoglobin in different conditions (native, denatured and lyophilized), as well as of hematin-NO were obtained in the temperature range of 80 K-280 K. There is a substantial and reversible.decrease of the areas of the EPR spectra of all the hemoglobin samples above 150 K. The interpretation of the results implies the existence of two conformational states in thermal equilibrium only one of which is EPR detectable. Thermodynamical parameters are determined for the hexa and penta-coordinated cases. (author). 25 refs, 3 figs.

Nitrosyl hemoglobins: EPR above 80 K

International Nuclear Information System (INIS)

Wajnberg, E.; Bemski, G.; El-Jaick, L.J.; Alves, O.C.

1995-03-01

The EPR spectra of nitrosyl hemoglobin and myoglobin in different conditions (native, denatured and lyophilized), as well as of hematin-NO were obtained in the temperature range of 80 K-280 K. There is a substantial and reversible.decrease of the areas of the EPR spectra of all the hemoglobin samples above 150 K. The interpretation of the results implies the existence of two conformational states in thermal equilibrium only one of which is EPR detectable. Thermodynamical parameters are determined for the hexa and penta-coordinated cases. (author). 25 refs, 3 figs

Theoretical Status of the RHIC Program

International Nuclear Information System (INIS)

Jalilian-Marian, Jamal

2006-01-01

Since the beginning of its operation, the Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Lab has produced a wealth of exciting and interesting results. I give a brief overview of the theoretical aspects of the main results from the RHIC program

A Model of RHIC Using the Unified Accelerator Libraries

Energy Technology Data Exchange (ETDEWEB)

Pilat, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trahern, C. G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Malitsky, N. [Cornell Univ., Ithaca, NY (United States)

1998-01-01

The Unified Accelerator Library (UAL) is an object oriented and modular software environment for accelerator physics which comprises an accelerator object model for the description of the machine (SMF, for Standard Machine Format), a collection of Physics Libraries, and a Perl inte,face that provides a homo­geneous shell for integrating and managing these components. Currently available physics libraries include TEAPOT++, a collection of C++ physics modules conceptually derived from TEAPOT, and DNZLIB, a differential algebra package for map generation. This software environment has been used to build a flat model of RHIC which retains the hierarchical lat­tice description while assigning specific characteristics to individual elements, such as measured field har­monics. A first application of the model and of the simulation capabilities of UAL has been the study of RHIC stability in the presence of siberian snakes and spin rotators. The building blocks of RHIC snakes and rotators are helical dipoles, unconventional devices that can not be modeled by traditional accelerator phys­ics codes and have been implemented in UAL as Taylor maps. Section 2 describes the RHIC data stores, Section 3 the RHIC SMF format and Section 4 the RHIC spe­cific Perl interface (RHIC Shell). Section 5 explains how the RHIC SMF and UAL have been used to study the RHIC dynamic behavior and presents detuning and dynamic aperture results. If the reader is not familiar with the motivation and characteristics of UAL, we include in the Appendix an useful overview paper. An example of a complete set of Perl Scripts for RHIC simulation can also be found in the Appendix.

Polarized proton beam for eRHIC

Energy Technology Data Exchange (ETDEWEB)

Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-05-03

RHIC has provided polarized proton collisions from 31 GeV to 255 GeV in the past decade. To preserve polarization through numerous depolarizing resonances through the whole accelerator chain, harmonic orbit correction, partial snakes, horizontal tune jump system and full snakes have been used. In addition, close attentions have been paid to betatron tune control, orbit control and beam line alignment. The polarization of 60% at 255 GeV has been delivered to experiments with 1.8×10¹¹ bunch intensity. For the eRHIC era, the beam brightness has to be maintained to reach the desired luminosity. Since we only have one hadron ring in the eRHIC era, existing spin rotator and snakes can be converted to six snake configuration for one hadron ring. With properly arranged six snakes, the polarization can be maintained at 70% at 250 GeV. This paper summarizes the effort and plan to reach high polarization with small emittance for eRHIC.

EVENT GENERATOR FOR RHIC SPIN PHYSICS

International Nuclear Information System (INIS)

SAITO, N.; SCHAEFER, A.

1999-01-01

This volume archives the reports from the RIKEN BNL Research Center workshop on ''Event Generator for RHIC Spin Physics II'' held during the week March 15, 1999 at Brookhaven National Laboratory. It was the second meeting on the subject following a first one in last September. This workshop has been initiated to establish a firm collaboration between theorists and experimentalists involved in RHIC spin physics with the aim of developing a reliable, high-precision event generator for RHIC spin physics. Needless to say, adequate event generators are indispensable tools for high energy physics programs in general, especially in the process of: planning the experimental programs; developing algorithms to extract the physics signals of interest; estimating the background in the extracted results, and connecting the final particle kinematics to the fundamental i.e. partonic level processes. Since RHIC is the first polarized collider, dedicated efforts are required to obtain a full-fledged event generator which describes spin dependent reactions in great detail

ANALYSIS OF AVAILABILITY AND RELIABILITY IN RHIC OPERATIONS

International Nuclear Information System (INIS)

PILAT, F.; INGRASSIA, P.; MICHNOFF, R.

2006-01-01

RHIC has been successfully operated for 5 years as a collider for different species, ranging from heavy ions including gold and copper, to polarized protons. We present a critical analysis of reliability data for RHIC that not only identifies the principal factors limiting availability but also evaluates critical choices at design times and assess their impact on present machine performance. RHIC availability data are typical when compared to similar high-energy colliders. The critical analysis of operations data is the basis for studies and plans to improve RHIC machine availability beyond the 50-60% typical of high-energy colliders

Thermoluminescence in alkali halides irradiated at 80K

International Nuclear Information System (INIS)

Jimenez de Castro, M.

1978-01-01

The thermoluminescence, the thermally stimulated currents and the thermal stability of the F centres induced in pure NaCl and KC1 crystals by X irradiation at 80K have been studied in detail, in the range between 80 and 300K. The thermoluminescent processes induced by illumination at 80K with F light in samples previously irradiated at room temperature has also been studied. It has been clearly observed the existence of thermoluminescent processes due to electrons and holes thermally released from traps, in which the F centres are not involved. The existence of hole-F centre recombination has not been observed. There are several thermoluminescent processes in both materials which are scribed to the recombination of F centres with mobile interstitial halogen atoms thermally released from traps, which are likely monovalent impurities in this temperature interval. The light emitting stage in these processes is originated by the formation of self trapped excitons. (Author) 66 refs

Experience with IBS-suppression lattice in RHIC

International Nuclear Information System (INIS)

Litvinenko, V.N.; Luo, Y.; Ptitsyn, V.; Satogata, T.; Tepikian, S.; Bai, M.; Bruno, D.; Cameron, P.; Connolly, R.; Della Penna, A.; Drees, A.; Fedotov, A.; Ganetis, G.; Hoff, L.; Louie, W.; Malitsky, N.; Marr, G.; Marusic, A.; Montag, C.; Pilat, F.; Roser, T.; Trbojevic, D.; Tsoupas, N.

2008-01-01

An intra-beam scattering (IBS) is the limiting factor of the luminosity lifetime for RHIC operating with heavy ions. In order to suppress the IBS we designed and implemented new lattice with higher betatron tunes. This lattice had been developed during last three years and had been used for gold ions in yellow ring of the RHIC during d-Au part of the RHIC Run-8. The use of this lattice allowed both significant increases in the luminosity lifetime and the luminosity levels via reduction of beta-stars in the IPS. In this paper we report on the development, the tests and the performance of IBS-suppression lattice in RHIC, including the resulting increases in the peak and the average luminosity. We also report on our plans for future steps with the IBS suppression

RHIC off-line computing

International Nuclear Information System (INIS)

Featherly, J.; Gibbard, B.; Gould, J.

1993-01-01

A report was prepared in Sept 1992, RHIC/DET Note 8, also known as ROCOCO, which estimated the various computing resources which will be required by the RHIC experimental program. A study has now been undertaken to review technical issues associated with supplying these resources. This study, organized by the HEP/NP Computing Group but including other appropriate participants, addresses questions of technologies, manpower, cost and schedule. The following document is an interim summary of this study both in terms of discussions which have occurred and initial conclusions reached

Results from STAR experiment at RHIC

Indian Academy of Sciences (India)

We present some of the important experimental results from nucleus–nucleus collision studies carried out by the STAR experiment at Relativistic Heavy Ion Collider (RHIC). The results suggests that central Au+Au collisions at RHIC has produced a dense and rapidly thermalizing matter with initial energy densities above the ...

USE OF PELTIER COOLERS AS SOIL HEAT FLUX TRANSDUCERS.

Science.gov (United States)

Weaver, H.L.; Campbell, G.S.

1985-01-01

Peltier coolers were modified and calibrated to serve as soil heat flux transducers. The modification was to fill their interiors with epoxy. The average calibration constant on 21 units was 13. 6 plus or minus 0. 8 kW m** minus **2 V** minus **1 at 20 degree C. This sensitivity is about eight times that of the two thermopile transducers with which comparisons were made. The thermal conductivity of the Peltier cooler transducers was 0. 4 W m** minus **1 degree C** minus **1, which is comparable to that of dry soil.

Ion optics of RHIC EBIS

Energy Technology Data Exchange (ETDEWEB)

Pikin, A.; Alessi, J.; Beebe, E.; Kponou, A.; Okamura, M.; Raparia, D.; Ritter, J.; Tan, Y.; Kuznetsov, G.

2011-09-10

RHIC EBIS has been commissioned to operate as a versatile ion source on RHIC injection facility supplying ion species from He to Au for Booster. Except for light gaseous elements RHIC EBIS employs ion injection from several external primary ion sources. With electrostatic optics fast switching from one ion species to another can be done on a pulse to pulse mode. The design of an ion optical structure and the results of simulations for different ion species are presented. In the choice of optical elements special attention was paid to spherical aberrations for high-current space charge dominated ion beams. The combination of a gridded lens and a magnet lens in LEBT provides flexibility of optical control for a wide range of ion species to satisfy acceptance parameters of RFQ. The results of ion transmission measurements are presented.

A study of RHIC crystal collimation

International Nuclear Information System (INIS)

Trbojevic, D.; Harrison, M.; Parker, B.; Thompson, P.; Stevens, A.; Biryukov, V.; Mokhov, N.; Drozhdin, A.

1998-01-01

The Relativistic Heavy Ion Collider (RHIC) will experience increasing longitudinal and transverse heavy ion emittances, mostly due to intra-beam scattering (IBS). The experiments in RHIC are expected to not only have reduced luminosities due to IBS but also background caused by beam halo. Primary betatron collimators will be used to remove the large amplitude particles. The efficiency of the primary collimator in RHIC strongly depends on the alignment of the jaws which needs to be within about ten micro-radians for the optimum conditions. As proposed by V. biryukov bent crystals could be used to improve the efficiency of an existing collimation system by installing them upstream of the collimator jaws. Bent crystals have been successfully used in SPS, Protvino and Fermilab for extraction of the beam particles channeled through them. This study examines possible improvements of the primary collimator system for heavy ions at RHIC by use of bent crystals. Bent crystals will reduce the collimator jaws alignment requirement and will increase collimator efficiency thereby reducing detector background

RHIC Proton Luminosity and Polarization Improvement

International Nuclear Information System (INIS)

Zhang, S. Y.

2014-01-01

The RHIC proton beam polarization can be improved by raising the Booster scraping, which also helps to reduce the RHIC transverse emittance, and therefore to improve the luminosity. By doing this, the beam-beam effect would be enhanced. Currently, the RHIC working point is constrained between 2/3 and 7/10, the 2/3 resonance would affect intensity and luminosity lifetime, and the working point close to 7/10 would enhance polarization decay in store. Run 2013 shows that average polarization decay is merely 1.8% in 8 hours, and most fills have the luminosity lifetime better than 14 hours, which is not a problem. Therefore, even without beam-beam correction, there is room to improve for RHIC polarization and luminosity. The key to push the Booster scraping is to raise the Booster input intensity; for that, two approaches can be used. The first is to extend the LINAC tank 9 pulse width, which has been successfully applied in run 2006. The second is to raise the source temperature, which has been successfully applied in run 2006 and run 2012.

RHIC BPM System Modifications and Performance

CERN Document Server

Satogata, Todd; Cameron, Peter; Cerniglia, Phil; Cupolo, John; Curcio, Anthony J; Dawson, William C; Degen, Christopher; Gullotta, Justin; Mead, Joe; Michnoff, Robert; Russo, Thomas; Sikora, Robert

2005-01-01

The RHIC beam position monitor (BPM) system provides independent average orbit and turn-by-turn (TBT) position measurements. In each ring, there are 162 measurement locations per plane (horizontal and vertical) for a total of 648 BPM planes in the RHIC machine. During 2003 and 2004 shutdowns, BPM processing electronics were moved from the RHIC tunnel to controls alcoves to reduce radiation impact, and the analog signal paths of several dozen modules were modified to eliminate gain-switching relays and improve signal stability. This paper presents results of improved system performance, including stability for interaction region and sextupole beam-based alignment efforts. We also summarize performance of improved million-turn TBT acquisition channels for nonlinear dynamics and echo studies.

Elastic proton-proton scattering at RHIC

Energy Technology Data Exchange (ETDEWEB)

Yip, K.

2011-09-03

Here we describe elastic proton+proton (p+p) scattering measurements at RHIC in p+p collisions with a special optics run of {beta}* {approx} 21 m at STAR, at the center-of-mass energy {radical}s = 200 GeV during the last week of the RHIC 2009 run. We present preliminary results of single and double spin asymmetries.

Proceedings of the symposium on RHIC detector R ampersand D

International Nuclear Information System (INIS)

Makdisi, Y.; Stevens, A.J.

1991-01-01

This report contains papers on the following topics: Development of Analog Memories for RHIC Detector Front-end Electronic Systems; Monolithic Circuit Development for RHIC at Oak Ridge National Laboratory; Highly Integrated Electronics for the STAR TPC; Monolithic Readout Circuits for RHIC; New Methods for Trigger Electronics Development; Neurocomputing methods for Pattern Recognition in Nuclear Physics; The Development of a Silicon Multiplicity Detector System; A Transition Radiation Detector for RHIC Featuring Accurate

Investigation of the vibration and EMC characteristics of miniature Stirling electric coolers for space applications

Science.gov (United States)

Kondratjev, V.; Gostilo, V.; Owens, anb A.

2017-08-01

We present the results of an investigation into the detrimental effects that electromechanical coolers can have on the spectral performance of compact, large volume HPGe spectrometers for space applications. Both mechanical vibration and electromagnetic pickup effects were considered, as well as a comparative assessment between three miniature Stirling cycle coolers—two Ricor model K508 coolers and one Thales model RM3 cooler. In spite of the limited number of coolers tested, the following conclusions can be made. There are significant differences in the vibration characteristics not only between the various types of cooler but also between coolers of the same type. It was also found that compared to the noise induced by mechanical vibrations, electromagnetic interference emanating from the embedded controllers does not significantly impact the energy resolution of detectors.

Physics and experiments at RHIC

International Nuclear Information System (INIS)

Young, G.R.

1995-01-01

The Relativistic Heavy Ion Collider (RHIC), under construction at Brookhaven National Laboratory, will be the site of a series of experiments seeking to discover the quark-gluon plasma and elucidate its properties. Several observables should exhibit characteristic behaviors if a quark-gluon plasma is indeed created in the laboratory. Four experiments are now under construction for RHIC to measure certain of these observables over kinematic ranges where effects due to quark-gluon plasma formation should be manifest

Analysis of ER string test thermally instrumented interconnect 80-K MLI blanket

International Nuclear Information System (INIS)

Daly, E.; Pletzer, R.

1992-04-01

An 80-K Multi Layer Insulation (MLI) blanket in the interconnect region between magnets DD0019 and DD0027 in the Fermi National Accelerator Laboratory (FNAL) ER string was instrumented with temperature sensors to obtain the steady-state temperature gradient through the blanket after string cooldown. A thermal model of the 80-K blanket assembly was constructed to analyze the steady-state temperature gradient data. Estimates of the heat flux through the 80-K MLI blanket assembly and predicted temperature gradients were calculated. The thermal behavior of the heavy polyethylene terapthalate (PET) cover layers separating the shield and inner blanket and inner and outer blankets was derived empirically from the data. The results of the analysis predict a heat flux of 0.363--0.453 W/m 2 based on the 11 sets of data. These flux values are 33--46% below the 80-K MLI blanket heat leak budget of 0.676 W/m 2 . The effective thermal resistance of the two heavy PET cover layers between the shield and inner blanket was found to be 2.1 times that of a single PET spacer layer, and the effective resistance of the two heavy PET cover layers between the inner blanket and outer blanket was found to be 7 times that of a single PET spacer layer. Based on these results, the 80-K MLI blanket assembly appears to be performing more than adequately to meet the 80-K static IR heat leak budget. However, these results should not be construed as a verification of the 80-K static IR heat leak, since no actual heat leak was measured. The results have been used to improve the empirically based model data in the 80-K MLI blanket thermal model, which has previously not included the effects of heavy PET cover layers on 80-K MLI blanket thermal performance

Proceedings of the symposium on RHIC detector R&D

Energy Technology Data Exchange (ETDEWEB)

Makdisi, Y.; Stevens, A.J. [eds.

1991-12-31

This report contains papers on the following topics: Development of Analog Memories for RHIC Detector Front-end Electronic Systems; Monolithic Circuit Development for RHIC at Oak Ridge National Laboratory; Highly Integrated Electronics for the STAR TPC; Monolithic Readout Circuits for RHIC; New Methods for Trigger Electronics Development; Neurocomputing methods for Pattern Recognition in Nuclear Physics; The Development of a Silicon Multiplicity Detector System; The Vertex Detector for the Lepton/Photon Collaboration; Simulations of Silicon Vertex Tracker for STAR Experiment at RHIC; Calorimeter/Absorber Optimization for a RHIC Dimuon Experiment (RD-10 Project); Applications of the LAHET simulation Code to Relativistic Heavy Ion Detectors; Highly Segmented, High Resolution Time-of-Flight System; Research and Development on a Sub 100 Picosecond Time-of-Flight System Based on Silicon Avalance Diodes; Behavior of TPC`s in a High Particle Flux Environment; Generic R&D on Undoped Cesium Iodide and Lead Fluoride; and A Transition Radiation Detector for RHIC Featuring Accurate Tracking and dE/dx Particle Identification. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

MEMS based shock pulse detection sensor for improved rotary Stirling cooler end of life prediction

Science.gov (United States)

Hübner, M.; Münzberg, M.

2018-05-01

The widespread use of rotary Stirling coolers in high performance thermal imagers used for critical 24/7 surveillance tasks justifies any effort to significantly enhance the reliability and predictable uptime of those coolers. Typically the lifetime of the whole imaging device is limited due to continuous wear and finally failure of the rotary compressor of the Stirling cooler, especially due to failure of the comprised bearings. MTTF based lifetime predictions, even based on refined MTTF models taking operational scenario dependent scaling factors into account, still lack in precision to forecast accurately the end of life (EOL) of individual coolers. Consequently preventive maintenance of individual coolers to avoid failures of the main sensor in critical operational scenarios are very costly or even useless. We have developed an integrated test method based on `Micro Electromechanical Systems', so called MEMS sensors, which significantly improves the cooler EOL prediction. The recently commercially available MEMS acceleration sensors have mechanical resonance frequencies up to 50 kHz. They are able to detect solid borne shock pulses in the cooler structure, originating from e.g. metal on metal impacts driven by periodical forces acting on moving inner parts of the rotary compressor within wear dependent slack and play. The impact driven transient shock pulse analyses uses only the high frequency signal <10kHz and differs therefore from the commonly used broadband low frequencies vibrational analysis of reciprocating machines. It offers a direct indicator of the individual state of wear. The predictive cooler lifetime model based on the shock pulse analysis is presented and results are discussed.

Phenomenology of the squeezed hadronic correlations at RHIC energies

International Nuclear Information System (INIS)

Padula, Sandra S.; Dudek, Danuce M.; Socolowski, Otavio Jr.

2012-01-01

We briefly review the basic theoretical results on bosonic back-to-back correlations (bBBC) and compare our predictions with the first experimental search for squeezed correlations of K + K - pairs, performed by PHENIX. The hadronic squeezed correlations are very sensitive to the functional form of the time emission distribution. The comparison is made for three different kaon time distributions. From such comparison we show that the outcome of the experimental search may still be inconclusive but it does not exclude the existence of squeezing effects on hadrons with in-medium modified masses already at RHIC energies. (author)

RHIC spin physics

International Nuclear Information System (INIS)

Bunce, G.

1994-01-01

The physics potential of colliding beams of protons, polarized either longitudinally or transversely, at RHIC is remarkable. A luminosity of L = 2 x 10 32 cm -2 with 70% polarized beams will be available with up to 250 GeV energy in each beam. The proposal to collide polarized protons in RHIC was submitted in August 1992 and approved in October 1993. We have funding for R ampersand D on Siberian Snakes, so that RHIC will be able to accelerate polarized protons early in its program. The expected date of the first heavy ion collisions is 1999. The spin physics program includes measurement of gluon and sea quark polarization in the longitudinally polarized proton, measurement and then application of parity violation in W and Z production, measurement of hard scattering parton-parton asymmetries, and quark polarization or transversity in transversely polarized protons. Single spin asymmetries allow sensitive searches for parity violation (longitudinal polarization), and correlations between quark spin and gluons (transverse). Probes include direct photons (to P T = 20 GeV/c), jets (to P T > 50 GeV/c), Drell-Yan pairs to M ell ell = 9 GeV, W ± , Z. This program is described in our Particle World paper. Here we will emphasize the new information included in our Update, given to the Brookhaven PAC this September

RHIC spin physics

International Nuclear Information System (INIS)

Bunce, G.

1993-01-01

The physics potential of colliding beams of protons, polarized either longitudinally or transversely, at RHIC is remarkable. A luminosity of L = 2 x 10 32 cm -2 sec -1 with 70% polarized beams will be available with up to 250 GeV energy in each beam. The proposal to collide polarized protons in RHIC was submitted in August 1992 and approved in October 1993, just after this workshop. The collaboration has been encouraged to complete R ampersand D on Siberian Snakes, so that RHIC will be able to accelerate polarized protons early in its program. The expected date of the first heavy ion collisions is 1999. The spin physics program includes measurement of gluon and sea quark polarization in the longitudinally polarized proton, measurement and then application of parity violation in W and Z production, measurement of hard scattering parton-parton asymmetries, and quark polarization or transversity in transversely polarized protons. Single spin asymmetries allow sensitive searches for parity violation (longitudinal polarization), and correlations between quark spin and gluons (transverse). Probes include direct photons (to p T = 20 GeV/c), jets (to p T > 50 GeV/c), Drell-Yan pairs (to m ll = 9 GeV), W +/- , Z. Here, the collaboration emphasizes the new information included in the Update, given to the Brookhaven PAC this September

The Recycler Electron Cooler

Energy Technology Data Exchange (ETDEWEB)

Shemyakin, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Prost, L. R. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

2013-03-19

The Recycler Electron cooler was the first (and so far, the only) cooler working at a relativistic energy (γ = 9.5). It was successfully developed in 1995-2004 and was in operation at Fermilab in 2005-2011, providing cooling of antiprotons in the Recycler ring. This paper describes the cooler, difficulties in achieving the required electron beam parameters and the ways to overcome them, cooling measurements, and details of operation.

Conceptual design of a quadrupole magnet for eRHIC

Energy Technology Data Exchange (ETDEWEB)

Witte, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-05-03

eRHIC is a proposed upgrade to the existing Relativistic Heavy Ion Collider (RHIC) hadron facility at Brookhaven National Laboratory, which would allow collisions of up to 21 GeV polarized electrons with a variety of species from the existing RHIC accelerator. eRHIC employs an Energy Recovery Linac (ERL) and an FFAG lattice for the arcs. The arcs require open-midplane quadrupole magnets of up to 30 T/m gradient of good field quality. In this paper we explore initial quadrupole magnet design concepts based on permanent magnetic material which allow to modify the gradient during operation.

High luminosity polarized proton collisions at RHIC

International Nuclear Information System (INIS)

Roser, T.

2001-01-01

The Brookhaven Relativistic Heavy Ion Collider (RHIC) provides the unique opportunity to collide polarized proton beams at a center-of-mass energy of up to 500 GeV and luminosities of up to 2 x 10 32 cm -2 s -1 . Such high luminosity and high energy polarized proton collisions will open up the possibility of studying spin effects in hard processes. However, the acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. After successful operation of RHIC with gold beams polarized protons from the AGS have been successfully injected into RHIC and accelerated using a full Siberian snakes built from four superconducting helical dipoles. A new high energy proton polarimeter was also successfully commissioned. Operation with two snakes per RHIC ring is planned for next year

RHIC prefire protection masks

International Nuclear Information System (INIS)

Drees, A.; Biscardi, C.; Curcio, T.; Gassner, D.; DeSanto, L.; Fu, W.; Liaw, C. J.; Montag, C.; Thieberger, P.; Yip, K.

2015-01-01

The protection of the RHIC experimental detectors from damage due to beam hitting close upstream elements in cases of abort kicker prefires requires some dedicated precautionary measures with two general options: to bring the beam close to a limiting aperture (i.e. the beam pipe wall), as far upstream of the detector components as possible or, alternatively, to bring a limiting aperture close to the circulating beam. Spontaneous and random prefires of abort kicker modules (Pulse Forming Network, PFN) have a history as long as RHIC is being operated. The abort system consist of 5 kickers in per ring, each of them equipped with its own dedicated PFN.

Advantages of polarization experiments at RHIC

International Nuclear Information System (INIS)

Underwood, D.G.

1991-01-01

We point out various spin experiments that could be done if the polarized beam option is pursued at RHIC. The advantages of RHIC for investigating several current and future physics problems are discussed. In particular, the gluon spin dependent structure function of the nucleon could be measured cleanly and systematically. Relevant experience developed in conjunction with the Fermilab Polarized Beam program is also presented

COMMISSIONING CNI PROTON POLARIMETERS IN RHIC

International Nuclear Information System (INIS)

HUANG, H.; BRAVAR, A.; LI, Z.; MACKAY, W.W.; MAKDISI, Y.; RESCIA, S.; ROSER, T.; SURROW, B.; BUNCE, G.; DESHPANDE, A.; GOTO, Y.; ET AL

2002-01-01

Two polarimeters based on proton carbon elastic scattering in the Coulomb Nuclear Interference (CNI) region have been installed and commissioned in the Blue and Yellow rings of RHIC during the first RHIC polarized proton collider run. Each polarimeter consists of ultra-thin carbon targets and six silicon detectors. With newly developed wave form digitizers, they provide fast and reliable polarization information for both rings

Parity violation experiments at RHIC

International Nuclear Information System (INIS)

Tannenbaum, M.J.

1993-01-01

With longitudinally polarized protons at RHIC, even a 1 month dedicated run utilizing both approved major detectors could produce a significant search for new physics in hadron collisions via parity violation. Additionally, in the energy range of RHIC, large ''conventional'' parity violating effects are predicted due to the direct production of the weak bosons W ± and Z 0 . One can even envision measurements of the spin dependent sea-quark structure functions of nucleons using the single-spin parity violating asymmetry of W ± and Z 0

100 kV, 80 kJ low-induction capacitor module

International Nuclear Information System (INIS)

Andrezen, A.B.; Burtsev, V.A.; Vodovozov, V.M.; Drozdov, A.A.; Makeev, G.M.

1980-01-01

A low induction capacitor module has been developed to investigate THETA- and Z-pinch plasma. Energy output time of the module lays in the microsecond range. The 100 kV, 80 kJ module is based on low-induction castor capasitors. The module is equipped with two solid dielectric dischargers, the system of discharger ignition protection system and automatic system for charging of capacitors. The module discharge period T 0 =5.6 μs. The capacitor module has been used in investigations of electric explosions of Al plane foils in the pulverized quartz. The overvoltage Usub(max)/Usub(o) approximately equal to 10 has been received at the maximum intensity of the electric field Esub(max) approximately equal to 12 kV/sm [ru

Advantages of polarization experiments at RHIC

International Nuclear Information System (INIS)

Underwood, D.G.

1990-01-01

We point out various spin experiments that could be done if the polarized beam option is pursued at RHIC. The advantages of RHIC for investigating several current and future physics problems are discussed. In particular, the gluon spin dependent structure function of the nucleon could be measured cleanly and systematically. Relevant experience developed in conjunction with the Fermilab Polarized Beam program is also presented. 8 refs., 2 tabs

Performance Analysis of Joule-Thomson Cooler Supplied with Gas Mixtures

Science.gov (United States)

Piotrowska, A.; Chorowski, M.; Dorosz, P.

2017-02-01

Joule-Thomson (J-T) cryo-coolers working in closed cycles and supplied with gas mixtures are the subject of intensive research in different laboratories. The replacement of pure nitrogen by nitrogen-hydrocarbon mixtures allows to improve both thermodynamic parameters and economy of the refrigerators. It is possible to avoid high pressures in the heat exchanger and to use standard refrigeration compressor instead of gas bottles or high-pressure oil free compressor. Closed cycle and mixture filled Joule-Thomson cryogenic refrigerator providing 10-20 W of cooling power at temperature range 90-100 K has been designed and manufactured. Thermodynamic analysis including the optimization of the cryo-cooler mixture has been performed with ASPEN HYSYS software. The paper describes the design of the cryo-cooler and provides thermodynamic analysis of the system. The test results are presented and discussed.

Development of a small Stirling-cycle cooler for spaceflight applications

Energy Technology Data Exchange (ETDEWEB)

Werrett, S.T.; Peskett, G.D.; Davey, G.; Bradshaw, T.W.; Delderfield, J.

1985-01-01

The paper describes the development, from a previously proven design approach, of a robust and simple Stirling-cycle cooler with long-life potential. The need for a closed-cycle refrigerator for use in a spacecraft borne infrared radiometer is explained. The refrigerator is to supply 1 watt of cooling at 80 K for less than 80 watts of input power, be able to survive the launch environment and subsequently run for 26000 hours. Clearance seals achieved with a spring suspension developed from earlier space-proven mechanisms have led to the production of a linear split Stirling-cycle machine with no apparent life limiting features. A servo-control system, in conjunction with moving coil motors and LVDT position sensors, permits running of balanced pairs of mechanisms. The working fluid, helium at a pressure of 1.2 MPa, is contained within titanium bodies having gold O-ring seals. A vacuum-bakeout procedure, based upon experience and outgassing trials, reduces residual contaminant release to acceptable levels. A prototype refrigerator was subjected to a vibration test and has subsequently run for 6000 hours with no detectable change in performance.

Development of a small Stirling cycle cooler for spaceflight applications

International Nuclear Information System (INIS)

Werrett, S.T.; Bradshaw, T.W.; Davey, G.; Delderfield, T.W.; Peskett, G.D.

1986-01-01

This paper describes the development, from a previously proven design approach, of a robust and simple Stirling cycle cooler with long life potential. The need for a closed cycle refrigerator for use in a spacecraft borne infra-red radiometer is explained. The refrigerator is to supply 1 watt of cooling at 80 K for less than 80 watts of input power, be able to survive the launch environment and subsequently run for 26000 hours. Clearance seals achieved with a spring suspension developed from earlier space proven mechanisms have led to the production of a linear split Stirling cycle machine with no apparent life limiting features. A servo control system, in conjunction with moving coil motors and LVDT position sensors, permits running of balanced pairs of mechanisms. The working fluid, helium at a pressure of 1.2 MPa, is contained within titanium bodies having gold O-ring seals. A vacuum bakeout procedure, based upon experience and outgassing trials, reduces residual contaminant release to acceptable levels. A prototype refrigerator has been subjected to a vibration test and has subsequently run for 6000 hours with no detectable change in performance

ATHENA X-IFU 300 K-50 mK cryochain demonstrator cryostat

Science.gov (United States)

Prouvé, T.; Duval, J. M.; Charles, I.; Yamasaki, N. Y.; Mitsuda, K.; Nakagawa, T.; Shinozaki, K.; Tokoku, C.; Yamamoto, R.; Minami, Y.; Le Du, M.; Andre, J.; Daniel, C.; Linder, M.

2018-01-01

In the framework of the ESA X-ray mission ATHENA, scheduled for launch in 2028, an ESA Core Technology Program (CTP) was started in 2016 to build a flight like cryostat demonstrator in parallel with the phase A studies of the ATHENA/X-IFU instrument [1,2]. As part of this CTP, called the Detector Cooling System (DCS), design, manufacturing and test of a cryostat including existing space coolers will be done. In addition to the validation of thermal performance, a Focal Plan Assembly (FPA) demonstrator using Transition Edge Sensors (TES) detector technology will be also integrated and its performance characterized versus the environment provided by the cryostat. This is a unique opportunity to validate many crucial issues of the cryogenic part of such a sensitive instrument. A dedicated activity within this CTP-DCS is the demonstration of the 300 K-50 mK cooling chain in a Ground System Equipment (GSE) cryostat. The studies are focused on the operation of the space coolers, which is made possible by the use of a ground cooler for cooling cryogenic shields and mechanical supports. Thanks to the modularity of the cryostat, several cooling chains could be tested. In the base line configuration described here, the low temperature stage is the CEA hybrid sorption/ADR 50 mK cooler with thermal interfaces at 4 K and 2 K. 4 K cooling is accomplished by a 4 K Joule-Thomson (JT) cryocooler and its Stirling precooler provided by JAXA. Regarding the 2 K stage, at first a 2 K JT from JAXA will be used. Alternatively, a 2 K JT cooler from RAL could replace the JAXA 2 K JT. In both cases new prototype(s) of a 2 K JT will be implemented, precooled by the EM 15 K pule tube cooler from Air Liquide. This test program is also the opportunity to validate the operation of the cryochain with respect to various requirements, such as time constant and temperature stabilities. This would bring us valuable inputs to integrate the cryochain in DCS cryostat or for the X-IFU phase A studies

Hypernucleus Production at RHIC and HIRFL-CSR Energy

International Nuclear Information System (INIS)

Zhang, S.; Xu, Z.; Chen, J.H.; Ma, Y.G.; Tang, Z.B.

2010-01-01

We calculated the hypertriton production at RHIC-STAR and HIRFL-CSR acceptance, with a multi-phase transport model (AMPT) and a relativistic transport model (ART), respectively. In specific, we calculated the Strangeness Population Factor S 3 = Λ 3 H/( 3 H e x Λ/p) at different beam energy. Our results from AGS to RHIC energy indicated that the collision system may change from hadronic phase at AGS energies to partonic phase at RHIC energies. Our calculation at HIRFL-CSR energy supports the proposal to measure hypertriton at HIRFL-CSR.

Estimation of collective instabilities in RHIC

International Nuclear Information System (INIS)

MacKay, W.W.; Blaskiewicz, M.; Deng, D.; Mane, V.; Peggs, S.; Ratti, A.; Rose, J.; Shea, T.J.; Wei, J.

1995-01-01

The authors have estimated the broadband impedance in RHIC to be |Z/n| +79 ions at transition with an estimated 10% growth in emittance for Z/n = 1.5 Ω. They summarize the sources of broad and narrow band impedances in RHIC and investigate the multibunch instability limits throughout the machine cycle. The largest contribution to the broadband impedance comes from the abort and injection kickers. Since RHIC is designed to accelerate fully stripped ions from H + up to Au +79 they give results for both protons and gold ions; other ions should give results somewhere between these two extremes. All ion species are expected to be stable during storage. At lower energies damping systems and chromaticity corrections will limit any growth to acceptable levels during the short time it takes to inject and accelerate the beams

The RHIC real time data link system

International Nuclear Information System (INIS)

Hartmann, H.

1997-01-01

The RHIC Real Time Data Link (RTDL) System distributes to all locations around the RHIC ring machine parameters of general interest to accelerator systems and users. The system, along with supporting host interface, is centrally located. The RTDL System is comprised of two module types: the Encoder Module (V105) and the Input Module (V106). There is only one V105 module, but many (up to 128) Input Modules. Multiple buffered outputs are provided for use locally or for retransmission to other RHIC equipment locations. Machine parameters are generated from the V115 Waveform Generator Module (WFG) or from machine hardware and coupled directly through a fiber optic serial link to one of the V106 input channels

Hadron spectroscopy and B physics at RHIC

International Nuclear Information System (INIS)

Chung, S.U.; Weygand, D.P.; Willutzki, H.J.

1991-11-01

A description is given of the physics opportunities at RHIC regarding quark-gluon spectroscopy. The basic idea is to isolate with appropriate triggers the sub-processes pomeron + pomeron → hadrons and γ * + γ * → hadrons with the net effective mass of hadrons in the range of 1.0 to 10.0 GeV, in order to study the hadronic states composed of quarks and gluons. The double-pomeron interactions are expected to produce glueballs and hybrids preferentially, while the two-offshell-photon initial states should couple predominantly to quarkonia and multiquark states. Of particular interest is the possibility of carrying out a CP-violation study in the self-tagging B decays, B d 0 → K + π - and bar B d 0 → K - π + . 20 refs., 4 figs

The color class condensate RHIC and HERA

CERN Document Server

McLerran, L

2002-01-01

In this talk, I discuss a universal form of matter, the color glass condensate. It is this matter which composes the low x part of all hadronic wavefunctions. The experimental programs at RHIC and HERA, and future programs at LHC and RHIC may allow us to probe and study the properties of this matter. (8 refs).

Studies and conception of a radiofrequency cooler for high intensity beams

International Nuclear Information System (INIS)

Duval, Florian

2009-01-01

The topic of this thesis is the study and the conception of a RFQ Cooler with buffer gas for high intensity radioactive beams. This project is in the frame of the next extension of GANIL, Spiral2, and the future low-energy facility DESIR ('Decay, Excitation and Storage of Radioactive ions'). The goal is to reduce the beams emittance of Spiral2 beams to allow their purification (ideally at isobaric level) with a high resolution separator. This cooler consists on a quadrupolar structure on which ions are confined by RF potential in opposite phase at an energy of 100 eV. A light buffer-gas, typically helium, is injected in the quadrupole and, after each collision, the ion lose a part of its energy and is finally cooled. The main problem on our project concerns the space charge. The existing devices are able to cool currents of few 10 nA whereas we have to treat beam intensities around 1 μA which induce an increase of the Coulomb repulsion between ions. That needs to produce strong RF fields which induce high RF potentials (≅ 10 kV_p_p) and a low inner radius (r_0 ≅ 3 a 5 mm). We have worked on a first prototype, SHIRaC-Phase1 ('Spiral2 High Intensity Radiofrequency Cooler'), with a 3 mm-inner radius, built at CSNSM-Orsay and moved at LPC-Caen at the end of 2007. The main R and D effort concerns the electronic part. A first RF system, based on a LC resonant circuit, has been developed and has provided up to 2500 V_p_p between 4.5 and 6.3 MHz. In these conditions, we have checked that we didn't have strong limitations from electrical breakdown between our electrodes. With this device, we have reduced the beam emittance to a value around 2 π.mm.mrad at 60 keV and the longitudinal energy spread to 146 meV. The maximum transmission of Sodium "2"3Na"+ and Rubidium "8"7Rb"+ is 25% with an ionization source for which the beam quality is better than Spiral2. For this reason, we have conceived a new cooler with an acceptance of 80 π.mm.mrad at 60 keV. This second

Beam Induced Pressure Rise at RHIC

CERN Document Server

Zhang, S Y; Bai, Mei; Blaskiewicz, Michael; Cameron, Peter; Drees, Angelika; Fischer, Wolfram; Gullotta, Justin; He, Ping; Hseuh Hsiao Chaun; Huang, Haixin; Iriso, Ubaldo; Lee, Roger C; Litvinenko, Vladimir N; MacKay, William W; Nicoletti, Tony; Oerter, Brian; Peggs, Steve; Pilat, Fulvia Caterina; Ptitsyn, Vadim; Roser, Thomas; Satogata, Todd; Smart, Loralie; Snydstrup, Louis; Thieberger, Peter; Trbojevic, Dejan; Wang, Lanfa; Wei, Jie; Zeno, Keith

2005-01-01

Beam induced pressure rise in RHIC warm sections is currently one of the machine intensity and luminosity limits. This pressure rise is mainly due to electron cloud effects. The RHIC warm section electron cloud is associated with longer bunch spacings compared with other machines, and is distributed non-uniformly around the ring. In addition to the countermeasures for normal electron cloud, such as the NEG coated pipe, solenoids, beam scrubbing, bunch gaps, and larger bunch spacing, other studies and beam tests toward the understanding and counteracting RHIC warm electron cloud are of interest. These include the ion desorption studies and the test of anti-grazing ridges. For high bunch intensities and the shortest bunch spacings, pressure rises at certain locations in the cryogenic region have been observed during the past two runs. Beam studies are planned for the current 2005 run and the results will be reported.

RHIC sextant test: Accelerator systems and performance

Energy Technology Data Exchange (ETDEWEB)

Pilat, F.; Trbojevic, D.; Ahrens, L. [and others

1997-08-01

One sextant of the RHIC Collider was commissioned in early 1997 with beam. We describe here the performance of the accelerator systems, instrumentation subsystems and application software. We also describe a ramping test without beam that took place after the commissioning with beam. Finally, we analyze the implications of accelerator systems performance and their impact on the planning for RHIC installation and commissioning.

RHIC sextant test: Accelerator systems and performance

International Nuclear Information System (INIS)

Pilat, F.; Trbojevic, D.; Ahrens, L.

1997-01-01

One sextant of the RHIC Collider was commissioned in early 1997 with beam. We describe here the performance of the accelerator systems, instrumentation subsystems and application software. We also describe a ramping test without beam that took place after the commissioning with beam. Finally, we analyze the implications of accelerator systems performance and their impact on the planning for RHIC installation and commissioning

RHIC Beam Loss Monitor System Initial Operation

International Nuclear Information System (INIS)

Witkover, R. L.; Michnoff, R. J.; Geller, J. M.

1999-01-01

The RHIC Beam Loss Monitor (BLM) System is designed to prevent beam loss quenching of the superconducting magnets, and acquire loss data. Four hundred ion chambers are located around the rings to detect losses. The required 8-decade range in signal current is compressed using an RC pre-integrator ahead of a low current amplifier. A beam abort may be triggered if fast or slow losses exceed programmable threshold levels. A micro-controller based VME module sets references and gains and reads trip status for up to 64 channels. Results obtained with the detectors in the RHIC Sextant Test and the prototype electronics in the AGS-to-RHIC (AtR) transfer line are presented along with the present status of the system

Independent criticality safety evaluation of deposits in cooler equipment in Building K-31 at the Oak Ridge K-25 Site, Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1996-10-01

This report provides an independent assessment of nuclear criticality issues associated with uranium deposits in the West and East Coolers for the 6A Booster Station in Building K-31 at the Oak Ridge K-25 Site. This assessment investigates the applicability of the initial assumptions used by Lockheed Martin Energy Systems (Energy Systems) and evaluates criticality calculations previously completed by Energy Systems. The calculations were independently verified. Each component was evaluated for its ability to satisfy requirements for subcriticality and meet the double contingency principle. Facility walk downs, detailed neutronics analysis, and fault tree analysis (FTA) were performed. The facility walk downs provided a better understanding of the building condition and status, equipment configuration, and uranium deposit locations. The detailed neutronics analysis focused on system geometry and moderation levels applicable to the individual components. The FTA considered the annual rate of occurrence for the events identified as potential causes of criticality issues. This report also examines the advantages of using this type of evaluation to assess the removal process for additional components and equipment

Implementation of Ramp Control in RHIC

International Nuclear Information System (INIS)

Kewisch, J.

1999-01-01

After the injection of beam into RHIC the beam energy is ramped from 10.8 GeV/u to 108 GeV/u and the beta function of the interaction points is reduced from 10 meters to 1 meter. The set points for magnet power supplies and RF cavities is changed during such ramps in concert. A system of Wave Form Generators (WFGs), interconnected by a Real Time Data Link (RTDL) and Event Link is used to control these devices. RHIC ramps use a two level system of WFGs: one transmits the beam energy and a ''pseudo time'' variable as functions of time via RTDL; the other calculates the device set points as functions of these RTDL variables. Energy scaling, saturation correction and the wiring of interaction region quadruples is performed on the second level. This report describes the configuration and implementation of the software, firmware and hardware of the RHIC ramp system

The STAR experiment at RHIC

International Nuclear Information System (INIS)

Marx, J.N.

1994-01-01

STAR (Solenoidal Tracker at RHIC) will be one of two large, sophisticated experiments ready to take data when the Relativistic Heavy Ion Collider (RHIC) comes on-line in 1999. The design of STAR, its construction and commissioning and the physics program using the detector are the responsibility of a collaboration of over 250 members from 30 institutions, world-wide. The overall approach of the STAR Collaboration to the physics challenge of studying collisions of highly relativistic nuclei is to focus on measurements of the properties of the many hadrons produced in the collisions. The STAR detector is optimized to detect and identify hadrons over a large solid angle so that individual events can be characterized, in detail, based on their hadronic content. The broad capabilities of the STAR detector will permit an examination of a wide variety of proposed signatures for the Quark Gluon Plasma (QGP), using the sample of events which, on an event-by-event basis, appear to come from collisions resulting in a large energy density over a nuclear volume. In order to achieve this goal, the STAR experiment is based on a solenoid geometry with tracking detectors using the time projection chamber approach and covering a large range of pseudo-rapidity so that individual tracks can be seen within the very high track density expected in central collisions at RHIC. STAR also uses particle identification by the dE/dx technique and by time-of-flight. Electromagnetic energy is detected in a large, solid-angle calorimeter. The construction of STAR, which will be located in the Wide Angle Hall at the 6 o'clock position at RHIC, formally began in early 1993

OVERVIEW OF THE RHIC INSERTION REGION, SEXTUPOLE, AND SNAKE POWER SUPPLY SYSTEMS

International Nuclear Information System (INIS)

BRUNO, D.; ENG, W.; GANETIS, G.; LAMBIASE, R.F.; SANDBERG, J.

2001-01-01

The Relativistic Heavy Ion Collider (RHIC) was commissioned in 1999 and 2000. RHIC requires power supplies to supply currents to highly inductive superconducting magnets. The RHIC Insertion Region (IR) contains many shunt power supplies to trim the current of different magnet elements in a large superconducting magnet circuit. There are a total of 237 Insertion Region power supplies in both RHIC rings. RHIC also requires sextupole power supplies. One sextupole power supply is connected across 12 sextupole magnets. There are a total of 24 sextupole power supplies in both rings. Snake magnets are also a part of the RHIC ring, and these snake magnets also require power supplies. There shall be a total of 24 snake power supplies in both rings. Power supply technology, connections, control systems and interfacing with the Quench Protection System will be presented

Dilepton Production at Fermilab and RHIC

International Nuclear Information System (INIS)

Peng, J.C.; McGaughey, P.L.; Moss, J.M.

1999-01-01

Some recent results from several fixed-target dimuon production experiments at Fermilab are presented. In particular, we discuss the use of Drell-Yan data to determine the flavor structure of the nucleon sea, as well as to deduce the energy-loss of partons traversing nuclear medium. Future dilepton experiments at RHIC could shed more light on the flavor asymmetry and possible charge-symmetry-violation of the nucleon sea. Clear evidence for scaling violation in the Drell-Yan process could also be revealed at RHIC

Modeling RHIC using the standard machine formal accelerator description

International Nuclear Information System (INIS)

Pilat, F.; Trahern, C.G.; Wei, J.

1997-01-01

The Standard Machine Format (SMF) is a structured description of accelerator lattices which supports both the hierarchy of beam lines and generic lattice objects as well as those deviations (field errors, alignment efforts, etc.) associated with each component of the as-installed machine. In this paper we discuss the use of SMF to describe the Relativistic Heavy Ion Collider (RHIC) as well as the ancillary data structures (such as field quality measurements) that are necessarily incorporated into the RHIC SMF model. Future applications of SMF are outlined, including its use in the RHIC operational environment

A NEW RELATIVE PROTON POLARIMETER FOR RHIC

International Nuclear Information System (INIS)

HUANG, H.; ALEKSEEV, I.; BUNCE, G.; BRUNER, N.; DESHPANDE, A.; GOTO, Y.; FIELDS, D.; IMAI, K.

2001-01-01

An innovative polarimeter based on proton carbon elastic scattering in the Coulomb Nuclear Interference (CNI) region has been installed and commissioned in the Blue ring of RHIC during the first RHIC polarized proton commissioning in September, 2000. The polarimeter consists of ultra-thin carbon targets and four silicon detectors. All elements are in a 1.6 meter vacuum chamber. This paper summarizes the polarimeter design issues and recent commissioning results

Global Decoupling on the RHIC Ramp

CERN Document Server

Luo, Yun; Della Penna, Al; Fischer, Wolfram; Laster, Jonathan S; Marusic, Al; Pilat, Fulvia Caterina; Roser, Thomas; Trbojevic, Dejan

2005-01-01

The global betatron decoupling on the ramp is an important issue for the operation of the Relativistic Heavy Ion Collider (RHIC). In the polarized proton run, the betatron tunes are required to keep almost constant on the ramp to avoid spin resonance line crossing and the beam polarization loss. Some possible correction schemes on the ramp, like three-ramp correction, the coupling amplitude modulation and the coupling phase modulaxtion, have been found. The principles of these schemes are shortly reviewed and compared. Operational results of their applications on the RHIC ramps are given.

ACCELERATION OF POLARIZED PROTONS AT RHIC

International Nuclear Information System (INIS)

HUANG, H.

2002-01-01

Relativistic Heavy Ion Collider (RHIC) ended its second year of operation in January 2002 with five weeks of polarized proton collisions. Polarized protons were successfully injected in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. This is the first time that polarized protons have been accelerated to 100 GeV. The machine performance and accomplishments during the polarized proton run will be reviewed. The plans for the next polarized proton run will be outlined

BROOKHAVEN: Major detectors for RHIC under construction

International Nuclear Information System (INIS)

Ludlam, Thomas W.

1994-01-01

On March 9-10, a cost and schedule review at Brookhaven verified construction readiness for the PHENIX detector (May 1993, page 10). PHENIX thus joins STAR (Solenoidal Tracking at RHIC - November 1991, page 17), whose construction plan was ratified in January 1993, as a major detector to take data when the RHIC heavy ion collider is completed in mid-1999. The goal of both detectors is to search for the transition from ordinary nuclear matter to a new state of matter consisting of (momentarily) unconfined quarks and gluons. This transition to a ''quark-gluon plasma'' (QGP) is predicted to occur under extreme conditions of temperature and energy density, as is likely to be the case in the collision of heavy ions of sufficient energy. RHIC is expected to produce the highest energy densities ever observed on the nuclear scale

The COOLER Code

DEFF Research Database (Denmark)

Siragusa, Mattia; Baiocco, Giorgio; Fredericia, Nina Pil Møntegaard

2017-01-01

COmputation of Local Electron Release (COOLER), a software program designed for dosimetry assessment at the cellular/subcellular scale, with a given distribution of administered low-energy electron-emitting radionuclides in cellular compartments, which remains a critical step in risk/benefit...... calculations with PARTRAC. Results from PARTRAC calculations on electron range, stopping power and residual energy versus traveled distance curves are presented and, when useful for implementation in COOLER, analytical fit functions are given. Example configurations for cells in different culture conditions (V...

Critical examination of RHIC paradigms - mostly high pT

International Nuclear Information System (INIS)

Tannenbaum, M.I.

2009-01-01

A critical examination of RHIC paradigms is presented. Topics include: search for a critical point with a low energy scan; the lack of understanding of radiative processes in a medium in QCD compared in detail to examples from QED; the reason why some physicists started to measure particles at large p T in the 1960's; a review of the discovery of hard-scattering in p-p collisions in the 1970's via single-inclusive and two-particle correlations and application of these techniques at RHIC. Several paradigms in both soft and hard physics which are popular at RHIC are discussed and challenged.

QCD and Heavy Ions RHIC Overview

CERN Document Server

Granier de Cassagnac, Raphael

2010-01-01

Nowadays, the most violent heavy ion collisions available to experimental study occur at the Relativistic Heavy Ion Collider (RHIC) of the Brookhaven National Laboratory. There, gold ions collide at psNN = 200 GeV. The early and most striking RHIC results were summarised in 2005 by its four experiments, BRAHMS, PHENIX, PHOBOS and STAR, in their so-called white papers [1, 2, 3, 4] that will be largely referenced thereafter. Beyond and after this, a wealth of data has been collected and analysed, providing additional information about the properties of the matter created at RHIC. It is categorically impossible to give a comprehensive review of these results in a 20 minutes talk or a 7 pages report. Here, I have made a selection of some of the most striking or intriguing signatures: jet quenching in Section 2, quarkonia suppressions in Section 3 and thermal photons in Section 4. A slightly longer and older version of this review can be found in [5]. Some updates are given here, as well as emphasis on new probes ...

RHIC beam loss monitor system design

International Nuclear Information System (INIS)

Witkover, R.; Zitvogel, E.; Michnoff, R.

1997-01-01

The Beam Loss Monitor (BLM) System is designed to prevent the quenching of RHIC magnets due to beam loss, provide quantitative loss data, and the loss history in the event of a beam abort. The system uses 400 ion chambers of a modified Tevatron design. To satisfy fast (single turn) and slow (100 msec) loss beam criteria and provide sensitivity for studies measurements, a range of over 8 decades is needed. An RC pre-integrator reduces the dynamic range for a low current amplifier. This is digitized for data logging. The output is also applied to an analog multiplier which compensates the energy dependence, extending the range of the abort comparators. High and low pass filters separate the signal to dual comparators with independent programmable trip levels. Up to 64 channels, on 8 VME boards, are controlled by a micro-controller based VME module, decoupling it from the front-end computer (FEC) for real-time operation. Results with the detectors in the RHIC Sextant Test and the electronics in the AGS-to-RHIC (AtR) transfer line will be presented

Proceedings of the third workshop on experiments and detectors for a relativistic heavy ion collider (RHIC)

International Nuclear Information System (INIS)

Shivakumar, B.; Vincent, P.

1988-01-01

This report contains papers on the following topics: the RHIC Project; summary of the working group on calorimetry; J//Psi/ measurements in heavy ion collisions at CERN; QCD jets at RHIC; tracking and particle identification; a 4π tracking spectrometer for RHIC; Bose-Einstein measurements at RHIC in light of new data; summary of working group on read-out electronics; data acquisition for RHIC; summary of the working group on detector simulation; B-physics at RHIC; and CP violation revisited at BNL, B-physics at RHIC

Preparing accelerator systems for the RHIC sextant commissioning

International Nuclear Information System (INIS)

Trbojevic, D.; Pilat, F.; Ahrens, L.

1997-01-01

The Relativistic Heavy Ion Collider (RHIC) construction is progressing steadily towards completion in 1999 when beams will circulate in both collider rings. One of the major tests of the RHIC project was the commissioning of the first sextant with gold ion beams in early 1997. This is a report on preparation of the RHIC accelerator systems for the first sextant test. It includes beam position monitors, timing, injection correction through the magnetic septum and kickers, current transformers, flags and the ionization beam profile monitors, beam loss monitors, beam and quench permit link system, power supply controls, and the configuration database system. The software and hardware development and coordination of the different systems before commissioning were regularly checked during bi-weekly, and (later) weekly, progress report meetings

Statistical analysis of RHIC beam position monitors performance

Science.gov (United States)

Calaga, R.; Tomás, R.

2004-04-01

A detailed statistical analysis of beam position monitors (BPM) performance at RHIC is a critical factor in improving regular operations and future runs. Robust identification of malfunctioning BPMs plays an important role in any orbit or turn-by-turn analysis. Singular value decomposition and Fourier transform methods, which have evolved as powerful numerical techniques in signal processing, will aid in such identification from BPM data. This is the first attempt at RHIC to use a large set of data to statistically enhance the capability of these two techniques and determine BPM performance. A comparison from run 2003 data shows striking agreement between the two methods and hence can be used to improve BPM functioning at RHIC and possibly other accelerators.

Statistical analysis of RHIC beam position monitors performance

Directory of Open Access Journals (Sweden)

R. Calaga

2004-04-01

Full Text Available A detailed statistical analysis of beam position monitors (BPM performance at RHIC is a critical factor in improving regular operations and future runs. Robust identification of malfunctioning BPMs plays an important role in any orbit or turn-by-turn analysis. Singular value decomposition and Fourier transform methods, which have evolved as powerful numerical techniques in signal processing, will aid in such identification from BPM data. This is the first attempt at RHIC to use a large set of data to statistically enhance the capability of these two techniques and determine BPM performance. A comparison from run 2003 data shows striking agreement between the two methods and hence can be used to improve BPM functioning at RHIC and possibly other accelerators.

Chasing the unicorn: RHIC and the QGP

International Nuclear Information System (INIS)

Pisarski, Robert D.; Niels Bohr Institute, Copenhagen; J. W. Goethe Univ., Frankfurt

2006-01-01

At nonzero temperature, it is expected that QCD undergoes a phase transition to a deconfined, chirally symmetric phase, the Quark-Gluon Plasma (QGP). I review what we expect theoretically about this possible transition, and what we have learned from heavy ion experiments at RHIC. I argue that while there are unambiguous signals for qualitatively new behavior at RHIC, versus experiments at lower energies, that in detail, no simple theoretical model can explain all salient features of the data. (author)

Chasing the unicorn: RHIC and the QGP

Energy Technology Data Exchange (ETDEWEB)

Pisarski, Robert D. [Brookhaven National Lab., Upton, NY (United States). Nuclear Theory and High Energy Theory Nuclear Theory Groups; Niels Bohr Institute, Copenhagen (Denmark); J. W. Goethe Univ., Frankfurt (Germany). Frankfurt Institute for Advanced Study

2006-03-15

At nonzero temperature, it is expected that QCD undergoes a phase transition to a deconfined, chirally symmetric phase, the Quark-Gluon Plasma (QGP). I review what we expect theoretically about this possible transition, and what we have learned from heavy ion experiments at RHIC. I argue that while there are unambiguous signals for qualitatively new behavior at RHIC, versus experiments at lower energies, that in detail, no simple theoretical model can explain all salient features of the data. (author)

Machine Protection System for Concurrent Operation of RHIC and BLIP

CERN Document Server

Wilinski, Michelle; Glenn, Joseph; Mausner, Leonard; Unger, Kerry

2005-01-01

The Brookhaven 200 MeV linac is a multipurpose machine used to inject low intensity polarized protons ultimately ending up in RHIC as well as to inject high intensity protons to BLIP, a medical isotope production facility. If high intensity protons were injected to RHIC by mistake, administrative radiation limits could be exceeded or sensitive electronics could be damaged. In the past, the changeover from polarized proton to high intensity proton operation has been a lengthy process, thereby never allowing the two programs to run simultaneously. To remedy this situation and allow for concurrent operation of RHIC and BLIP, an active interlock system has been designed to monitor current levels in the AGS using two current transformers with fail safe circuitry and associated electronics to inhibit beam to RHIC if high intensity is detected.

How the Performance of a Superconducting Magnet is affected by the Connection between a small cooler and the Magnet

International Nuclear Information System (INIS)

Green, Michael A.

2005-01-01

As low temperature cryocoolers become more frequently used to cool superconducting magnets, it becomes increasingly apparent that the connection between the cooler and the magnet has an effect on the design and performance of the magnet. In general, the use of small coolers can be considered in two different temperature ranges; (1) from 3.8 to 4.8 K for magnet fabricated with LTS conductor and (2) from 18 to 35 K for magnets fabricated using HTS conductor. In general, both temperature ranges call for the use of a two-stage cooler. The best method for connecting a cooler to the magnet depends on a number of factors. The factors include: (1) whether the cooler must be used to cool down the magnet from room temperature, (2) whether the magnet must have one or more reservoirs of liquid cryogen to keep the magnet cold during a loss of cooling, and (3) constraints on the distance from the cooler cold heads and the magnet and its shield. Two methods for connecting low temperature coolers to superconducting magnets have been studied. The first method uses a cold strap to connect the cold heads directly to the loads. This method is commonly used for cryogen-free magnets. The second method uses a thermal siphon and liquid cryogens to make the connection between the load being cooled and the cold head. The two methods of transferring heat from the magnet to the cooler low temperature cold head are compared for the two temperature ranges given above

Summary of the RHIC Retreat 2008

International Nuclear Information System (INIS)

Pilat, F.; Brennan, M.; Brown, K.; Fischer, W.; Montag, C.

2008-01-01

The main goal of the RHIC Retreat is to review last run's performance and prepare for the next. As always though we also discussed the longer term goals and plans for the facility to put the work in perspective and in the right priority. A straw-man plan for the facility was prepared for the DOE that assumes 30 cryoweek and running 2 species per year. The plan outlines RHIC operations for 2008-2012 and integrates well accelerator and detector upgrades to optimize the physics output with high luminosities. The plans includes guidance from the PAC and has been reviewed by DOE

SIMULATION OF PARTICLE SPECTRA AT RHIC

International Nuclear Information System (INIS)

KAHANA, D.E.; KAHANA, S.H.

2001-01-01

A purely hadronic simulation is performed of the recently reported data from PHOBOS at energies of √s = 56, 130 GeV using the relativistic heavy ion cascade LUCIFER which had previously given a good description of the NA49 inclusive spectra at √s = 17.2 GeV/A. The results compare well with these early measurements at RHIC and indeed successfully predict the increase in multiplicity now seen by PHOBOS and the other RHIC detectors at the nominal maximum energy of √s = 200 GeV/A, suggesting that evidence for quark-gluon matter remains elusive

THE RHIC SEQUENCER

International Nuclear Information System (INIS)

VAN ZEIJTS, J.; DOTTAVIO, T.; FRAK, B.; MICHNOFF, R.

2001-01-01

The Relativistic Heavy Ion Collider (RHIC) has a high level asynchronous time-line driven by a controlling program called the ''Sequencer''. Most high-level magnet and beam related issues are orchestrated by this system. The system also plays an important task in coordinated data acquisition and saving. We present the program, operator interface, operational impact and experience

Micromachined Joule-Thomson coolers for cooling low-temperature detectors and electronics

Science.gov (United States)

ter Brake, Marcel; Lerou, P. P. P. M.; Burger, J. F.; Holland, H. J.; Derking, J. H.; Rogalla, H.

2017-11-01

The performance of electronic devices can often be improved by lowering the operating temperature resulting in lower noise and larger speed. Also, new phenomena can be applied at low temperatures, as for instance superconductivity. In order to fully exploit lowtemperature electronic devices, the cryogenic system (cooler plus interface) should be `invisible' to the user. It should be small, low-cost, low-interference, and above all very reliable (long-life). The realization of cryogenic systems fulfilling these requirements is the topic of research of the Cooling and Instrumentation group at the University of Twente. A MEMS-based cold stage was designed and prototypes were realized and tested. The cooler operates on basis of the Joule-Thomson effect. Here, a high-pressure gas expands adiabatically over a flow restriction and thus cools and liquefies. Heat from the environment (e.g., an optical detector) can be absorbed in the evaporation of the liquid. The evaporated working fluid returns to the low-pressure side of the system via a counter-flow heat exchanger. In passing this heat exchanger, it takes up heat from the incoming high-pressure gas that thus is precooled on its way to the restriction. The cold stage consists of a stack of three glass wafers. In the top wafer, a high-pressure channel is etched that ends in a flow restriction with a height of typically 300 nm. An evaporator volume crosses the center wafer into the bottom wafer. This bottom wafer contains the lowpressure channel thus forming a counter-flow heat exchanger. A design aiming at a net cooling power of 10 mW at 96 K and operating with nitrogen as the working fluid was optimized based on the minimization of entropy production. The optimum cold finger measures 28 mm x 2.2 mm x 0.8 mm operating with a nitrogen flow of 1 mg/s at a high pressure of 80 bar and a low pressure of 6 bar. The design and fabrication of the coolers will be discussed along with experimental results.

Beam profile measurements on RHIC

International Nuclear Information System (INIS)

Connolly, R.; Michnoff, R.; Moore, T.; Shea, T.; Tepikian, S.

2000-01-01

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Lab was commissioned during the summer of 1999. Transverse beam profiles on RHIC are measured with ionization profile monitors (IPMs). An IPM measures beam profiles by collecting the electrons liberated by residual gas ionization by the beam. The detector is placed in the gap of a dipole magnet to force the electrons to travel in straight lines from the beamline center to the collector. One IPM was tested and it measured the profiles of a single gold bunch containing 10 8 ions on consecutive turns. We show an example of one of these profiles giving transverse emittance. Also several profiles are combined into a mountain-range plot which shows betatron oscillations at injection

MACHINE PROTECTION SYSTEM FOR CONCURRENT OPERATION OF RHIC AND BLIP

International Nuclear Information System (INIS)

WILINSKI, M.; BELLAVIA, S.; GLENN, J.W.; MAUSNER, L.F.; UNGER, K.L.

2005-01-01

The Brookhaven 200MeV linac is a multipurpose machine used to inject low intensity polarized protons for RHIC (Relativistic Heavy Ion Collider), as well as to inject high intensity protons to BLIP (Brookhaven Linac Isotope Producer), a medical isotope production facility. If high intensity protons were injected to RHIC by mistake, administrative radiation limits could be exceeded or sensitive electronics could be damaged. In the past, the changeover from polarized proton to high intensity proton operation has been a lengthy process, thereby never allowing the two programs to run simultaneously. To remedy this situation and allow concurrent operation of RHIC and BLIP, an active interlock system has been designed to monitor current levels in the AGS using two current transformers with fail safe circuitry and associated electronics to inhibit beam to RHIC if high intensity currents are detected

Synchrotron Radiation in eRHIC Interaction Region

CERN Document Server

Beebe-Wang, Joanne; Montag, Christoph; Rondeau, Daniel J; Surrow, Bernd

2005-01-01

The eRHIC currently under study at BNL consists of an electron storage ring added to the existing RHIC complex. The interaction region of this facility has to provide the required low-beta focusing while accommodating the synchrotron radiation generated by beam separation close to the interaction point. In the current design, the synchrotron radiation caused by 10GeV electrons bent by low-beta triplet magnets will be guided through the interaction region and dumped 5m downstream. However, it is unavoidable to stop a fraction of the photons at the septum where the electron and ion vacuum system are separated. In order to protect the septum and minimize the backward scattering of the synchrotron radiation, an absorber and collimation system will be employed. In this paper, we first present the overview of the current design of the eRHIC interaction region with special emphasis on the synchrotron radiation. Then the initial design of the absorber and collimation system, including their geometrical and physical p...

Recent RHIC in-situ coating technology developments

CERN Document Server

Hershcovitch, A.; Brennan, J.M.; Chawla, A.; Fischer, W.; Liaw, C-J; Meng, W.; Todd, R.; Custer, A.; Erickson, M.; Jamshidi, N.; Kobrin, P.; Laping, R.; Poole, H.J.; Jimenez, J.M.; Neupert, H.; Taborelli, M.; Yin-Vallgren, C.; Sochugov, N.

2013-04-22

To rectify the problems of electron clouds observed in RHIC and unacceptable ohmic heating for superconducting magnets that can limit future machine upgrades, we started developing a robotic plasma deposition technique for $in-situ$ coating of the RHIC 316LN stainless steel cold bore tubes based on staged magnetrons mounted on a mobile mole for deposition of Cu followed by amorphous carbon (a-C) coating. The Cu coating reduces wall resistivity, while a-C has low SEY that suppresses electron cloud formation. Recent RF resistivity computations indicate that 10 {\\mu}m of Cu coating thickness is needed. But, Cu coatings thicker than 2 {\\mu}m can have grain structures that might have lower SEY like gold black. A 15-cm Cu cathode magnetron was designed and fabricated, after which, 30 cm long samples of RHIC cold bore tubes were coated with various OFHC copper thicknesses; room temperature RF resistivity measured. Rectangular stainless steel and SS discs were Cu coated. SEY of rectangular samples were measured at ro...

RHIC beam permit and quench detection communications system

International Nuclear Information System (INIS)

Conkling, C.R. Jr.

1997-01-01

A beam permit module has been developed to concentrate RHIC, subsystem sensor outputs, permit beam, and initiate emergency shutdowns. The modules accept inputs from the vacuum, cryogenic, power supply, beam loss, and superconducting magnet quench detection systems. Modules are located at equipment locations around the RHIC ring. The modules are connected by three fiberoptic communications links; a beam permit link, and two magnet power supply interlock links. During operation, carrier presence allows beam. If a RHIC subsystem detects a fault, the beam permit carrier terminates - initiating a beam dump. If the fault was a superconducting magnet quench, a power supply interlock carrier terminates - initiating an emergency magnet power dump. In addition, the master module triggers an event to cause remote sensors to log and hold data at the time-of-failure

Transverse impedance measurement in RHIC and the AGS

Energy Technology Data Exchange (ETDEWEB)

Biancacci, Nicolo [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Dutheil, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Mernick, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; White, S. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

2014-05-12

The RHIC luminosity upgrade program aims for an increase of the polarized proton luminosity by a factor 2. To achieve this goal a significant increase in the beam intensity is foreseen. The beam coupling impedance could therefore represent a source of detrimental effects for beam quality and stability at high bunch intensities. For this reason it is essential to quantify the accelerator impedance budget and the major impedance sources, and possibly cure them. In this MD note we summarize the results of the 2013 transverse impedance measurements in the AGS and RHIC. The studies have been performed measuring the tune shift as a function of bunch intensity and deriving the total accelerator machine transverse impedance. For RHIC, we could obtain first promising results of impedance localization measurements as well.

Comparison of the Window-Frame RHIC-abort kicker with C-type Kicker

International Nuclear Information System (INIS)

Tsoupas, N.; McMahan, Brandon

2014-01-01

The high intensity proton bunches (~2.5x10 11 p/bunch ) circulating in RHIC increase the temperature of the ferrite-made RHIC-abort-kickers above the Curie point; as a result, the kickers cannot provide the required field to abort the beam at the beam dump. A team of experts in the CAD department worked on modifying the design of the window-frame RHIC-abort kicker to minimize the hysteresis losses responsible for the increase of the ferrite's temperature. In this technical note we report some results from the study of two possible modifications of the window-frame RHIC-abort kicker, and we compare these results with those of a propose C-type RHIC-abort kicker. We also include an Appendix where we describe a method which may further reduce the hysteresis losses of the window-frame kicker.

Flow in Au+Au collisions at RHIC

Science.gov (United States)

Belt Tonjes, Marguerite; the PHOBOS Collaboration; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Decowski, M. P.; García, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tang, J.-L.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wolfs, F. L. H.; Wosiek, B.; Wozniak, K.; Wuosmaa, A. H.; Wysłouch, B.

2004-08-01

The study of flow can provide information on the initial state dynamics and the degree of equilibration attained in heavy-ion collisions. This contribution presents results for both elliptic and directed flow as determined from data recorded by the PHOBOS experiment in Au+Au runs at RHIC at \\sqrt{sNN} = 19.6, 130 and 200 GeV. The PHOBOS detector provides a unique coverage in pseudorapidity for measuring flow at RHIC. The systematic dependence of flow on pseudorapidity, transverse momentum, centrality and energy is discussed.

Polarization simulations in the RHIC run 15 lattice

Energy Technology Data Exchange (ETDEWEB)

Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Luo, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; White, S. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

2015-05-03

RHIC polarized proton Run 15 uses a new acceleration ramp optics, compared to RHIC Run 13 and earlier runs, in relation with electron-lens beam-beam compensation developments. The new optics induces different strengths in the depolarizing snake resonance sequence, from injection to top energy. As a consequence, polarization transport along the new ramp has been investigated, based on spin tracking simulations. Sample results are reported and discussed.

Proceedings of RIKEN BNL Research Center workwhop on RHIC spin

Energy Technology Data Exchange (ETDEWEB)

SOFFER,J.

1999-10-06

This RHIC Spin Workshop is the 1999 annual meeting of the RHIC Spin Collaboration, and the second to be hosted at Brookhaven and sponsored by the RIKEN BNL Research Center. The previous meetings were at Brookhaven (1998), Marseille (1996), MIT in 1995, Argonne 1994, Tucson in 1991, and the Polarized Collider Workshop at Penn State in 1990. As noted last year, the Center provides a home for combined work on spin by theorists, experimenters, and accelerator physicists. This proceedings, as last year, is a compilation of 1 page summaries and 5 selected transparencies for each speaker. It is designed to be available soon after the workshop is completed. Speakers are welcome to include web or other references for additional material. The RHIC spin program and RHIC are rapidly becoming reality. RHIC has completed its first commissioning run, as described here by Steve Peggs. The first Siberian Snake for spin has been completed and is being installed in RHIC. A new polarized source from KEK and Triumf with over 1 milliampere of polarized H{sup minus} is being installed, described by Anatoli Zelenski. They have had a successful test of a new polarimeter for RHIC, described by Kazu Kurita and Haixin Huang. Spin commissioning is expected next spring (2000), and the first physics run for spin is anticipated for spring 2001. The purpose of the workshop is to get everyone together about once per year and discuss goals of the spin program, progress, problems, and new ideas. They also have many separate regular forums on spin. There are spin discussion sessions every Tuesday, now organized by Naohito Saito and Werner Vogelsang. The spin discussion schedule and copies of presentations are posted on http://riksg01.rhic.bnl.gov/rsc. Speakers and other spinners are encouraged to come to BNL and to lead a discussion on your favorite idea. They also have regular polarimeter and snake meetings on alternate Thursdays, led by Bill McGahern, the lead engineer for the accelerator spin

Proceedings of RIKEN BNL Research Center workshop on RHIC spin

International Nuclear Information System (INIS)

Soffer, J.

1999-01-01

This RHIC Spin Workshop is the 1999 annual meeting of the RHIC Spin Collaboration, and the second to be hosted at Brookhaven and sponsored by the RIKEN BNL Research Center. The previous meetings were at Brookhaven (1998), Marseille (1996), MIT in 1995, Argonne 1994, Tucson in 1991, and the Polarized Collider Workshop at Penn State in 1990. As noted last year, the Center provides a home for combined work on spin by theorists, experimenters, and accelerator physicists. This proceedings, as last year, is a compilation of 1 page summaries and 5 selected transparencies for each speaker. It is designed to be available soon after the workshop is completed. Speakers are welcome to include web or other references for additional material. The RHIC spin program and RHIC are rapidly becoming reality. RHIC has completed its first commissioning run, as described here by Steve Peggs. The first Siberian Snake for spin has been completed and is being installed in RHIC. A new polarized source from KEK and Triumf with over 1 milliampere of polarized H minus is being installed, described by Anatoli Zelenski. They have had a successful test of a new polarimeter for RHIC, described by Kazu Kurita and Haixin Huang. Spin commissioning is expected next spring (2000), and the first physics run for spin is anticipated for spring 2001. The purpose of the workshop is to get everyone together about once per year and discuss goals of the spin program, progress, problems, and new ideas. They also have many separate regular forums on spin. There are spin discussion sessions every Tuesday, now organized by Naohito Saito and Werner Vogelsang. The spin discussion schedule and copies of presentations are posted on http://riksg01.rhic.bnl.gov/rsc. Speakers and other spinners are encouraged to come to BNL and to lead a discussion on your favorite idea. They also have regular polarimeter and snake meetings on alternate Thursdays, led by Bill McGahern, the lead engineer for the accelerator spin effort

Heat Exchange and Fouling Analysis on a Set of Hydrogen Sulphide Gas Coolers

Directory of Open Access Journals (Sweden)

Andrés Adrian Sánchez-Escalona

2017-07-01

Full Text Available The sulphide acid coolers are tube and shell jacketed heat exchangers designed to cool down the produced gas from 416,15 K to 310,15 K in addition to separate the sulphur carried over by the outlet gas from the reactor tower. The investigation was carried out by applying the passive experimentation process in an online cooler set in order to determine the heat transfer rates and fouling based on heat resistance. It was corroborated that the operation of this equipment outside design parameters increases outlet gas temperature and liquid sulphur carryovers. Efficiency loss is caused by fouling elements in the fluid, which results in changes in the overall heat transfer rate. The linear tendency of the fouling heat resistance based on time for three gas flowrates.

The RHIC transfer line cable database

International Nuclear Information System (INIS)

Scholl, E.H.; Satogata, T.

1995-01-01

A cable database was created to facilitate and document installation of cables and wiring in the RHIC project, as well as to provide a data source to track possible wiring and signal problems. The eight tables of this relational database, currently implemented in Sybase, contain information ranging from cable routing to attenuation of individual wires. This database was created in a hierarchical scheme under the assumption that cables contain wires -- each instance of a cable has one to many wires associated with it. This scheme allows entry of information pertinent to individual wires while only requiring single entries for each cable. Relationships to other RHIC databases are also discussed

Summary of the RHIC Retreat 2008

Energy Technology Data Exchange (ETDEWEB)

Pilat,F.; Brennan, M.; Brown, K.; Fischer, W.; Montag, C.

2008-08-01

The main goal of the RHIC Retreat is to review last run's performance and prepare for the next. As always though we also discussed the longer term goals and plans for the facility to put the work in perspective and in the right priority. A straw-man plan for the facility was prepared for the DOE that assumes 30 cryoweek and running 2 species per year. The plan outlines RHIC operations for 2008-2012 and integrates well accelerator and detector upgrades to optimize the physics output with high luminosities. The plans includes guidance from the PAC and has been reviewed by DOE.

Mechanical design of 56 MHz superconducting RF cavity for RHIC collider

Energy Technology Data Exchange (ETDEWEB)

Pai, C.; Ben-Zvi, I.; Burrill, A.; Chang, X.; McIntyre, G.; Than, Y.; Tuozzolo, J.; Wu, Q.

2011-03-28

A 56 MHz Superconducting RF Cavity operating at 4.4K is being constructed for the RHIC collider. This cavity is a quarter wave resonator with beam transmission along the centerline. This cavity will increase collision luminosity by providing a large longitudinal bucket for stored bunches of RHIC ion beam. The major components of this assembly are the niobium cavity with the mechanical tuner, its titanium helium vessel and vacuum cryostat, the support system, and the ports for HOM and fundamental dampers. The cavity and its helium vessel must meet equivalent safety with the ASME pressure vessel code and it must not be sensitive to frequency shift due to pressure fluctuations from the helium supply system. Frequency tuning achieved by a two stage mechanical tuner is required to meet performance parameters. This tuner mechanism pushes and pulls the tuning plate in the gap of niobium cavity. The tuner mechanism has two separate drive systems to provide both coarse and fine tuning capabilities. This paper discusses the design detail and how the design requirements are met.

ERL-BASED LEPTON-HADRON COLLIDERS: eRHIC AND LHeC

CERN Document Server

Zimmermann, F

2013-01-01

Two hadron-ERL colliders are being proposed. The Large Hadron electron Collider (LHeC) plans to collide the high-energy protons and heavy ions in the Large Hadron Collider (LHC) at CERN with 60-GeV polarized electrons or positrons. The baseline scheme for this facility adds to the LHC a separate recirculating superconducting (SC) lepton linac with energy recovery, delivering a lepton current of 6.4mA. The electron-hadron collider project eRHIC aims to collide polarized (and unpolarized) electrons with a current of 50 (220) mA and energies in the range 5–30 GeV with a variety of hadron beams— heavy ions as well as polarized light ions— stored in the existing Relativistic Heavy Ion Collider (RHIC) at BNL. The eRHIC electron beam will be generated in an energy recovery linac (ERL) installed inside the RHIC tunnel.

Numerical spin tracking in a synchrotron computer code Spink: Examples (RHIC)

International Nuclear Information System (INIS)

Luccio, A.

1995-01-01

In the course of acceleration of polarized protons in a synchrotron, many depolarizing resonances are encountered. They are classified in two categories: Intrinsic resonances that depend on the lattice structure of the ring and arise from the coupling of betatron oscillations with horizontal magnetic fields, and imperfection resonances caused by orbit distortions due to field errors. In general, the spectrum of resonances vs spin tune Gγ(G = 1.7928, the proton gyromagnetic anomaly, and y the proton relativistic energy ratio) for a given lattice tune ν, or vs ν for a given Gγ, contains a multitude of lines with various amplitudes or resonance strengths. The depolarization due to the resonance lines can be studied by numerically tracking protons with spin in a model accelerator. Tracking will allow one to check the strength of resonances, to study the effects of devices like Siberian Snakes, to find safe lattice tune regions where to operate, and finally to study in detail the operation of special devices such as Spin Flippers. A few computer codes exist that calculate resonance strengths E k and perform tracking, for proton and electron machines. Most relevant to our work for the AGS and RHIC machines are the programs Depol and Snake. Depol, calculates the E k 's by Fourier analysis. The input to Depol is the output of a machine model code, such as Synch or Mad, containing all details of the lattice. Snake, does the tracking, starting from a synthetic machine, that contains a certain number of periods, of FODO cells, of Siberian snakes, etc. We believed the complexities of machines like the AGS or RHIC could not be adequately represented by Snake. Then, we decided to write a new code, Spink, that combines some of the features of Depol and Snake. I.E., Spink reads a Mad output like Depol and tracks as Snake does. The structure of the code and examples for RHIC are described in the following

PHOBOS at RHIC 2000

International Nuclear Information System (INIS)

Garcia, E.; Baum, R.; Bindel, R.; Mignerey, A.; Shea, J.; Back, B.B.; Betts, R.R.; George, N.; Wuosmaa, A.H.; Baker, M.D.; Barton, D.S.; Carroll, A.; Ceglia, M.; Gushue, S.; Heintzelman, G.A.; Kraner, H.; Olszewski, A.; Pak, R.; Remsberg, L.P.; Scaduto, J.; Sinacore, J.; Steinberg, P.; Sukhanov, A.; Bogucki, W.; Budzanowski, A.; Coghen, T.; Dabrowski, B.; Despet, M.; Galuszka, K.; Godlewski, J.; Halik, J.; Holynski, R.; Kita, W.; Kotula, J.; Lemler, M.; Ligocki, J.; Michalowski, J.; Sawicki, P.; Straczek, A.; Stodulski, M.; Strek, M.; Stopa, Z.; Trzupek, A.; Wosiek, B.; Wozniak, K.; Zychowski, P.; Bialas, A.; Czyz, W.; Zalewski, K.; Basilev, S.; Bates, B.D.; Busza, W.; Decowski, M.P.; Fita, P.; Fitch, J.; Friedl, M.; Gomes, C.; Griesmayer, E.; Gulbrandsen, K.; Haridas, P.; Henderson, C.; Kane, J.; Katzy, J.; Kulinich, P.; Law, C.; Mulmenstadt, J.; Neal, M.; Patel, M.; Pernegger, H.; Plesko, M.; Reed, C.; Roland, C.; Roland, G.; Ross, D.; Rosenberg, L.; Ryan, J.; Sarin, P.; Steadman, S.G.; Stephans, G.S.F.; Surowiecka, K.; Vale, C.M.; Van Nieuwenhuizen, G.J.; Verdier, R.; Wadsworth, B.; Wyslouch, B.; Chang, Y.H.; Chen, A.E.; Lin, W.T.; Tang, J.L.; Conner, C.; Ganz, R.; Halliwell, C.; Hollis, R.; Holzman, B.; Kucewicz, W.; McLeod, D.; Nouicer, R.; Reuter, M.; Hayes, A.; Johnson, E.; Manly, S.; Park, I.C.; Skulski, W.; Teng, R.; Wolfs, F.L.H.; Sanzgiri, A.

2001-01-01

The relativistic heavy ion collider (RHIC) at Brookhaven national laboratory delivered in June 2000 the first collisions between Au nuclei at the highest center-of-mass energies achieved in a controlled environment to date. PHOBOS is one of the four experiments installed during this phase of RHIC running. This paper will describe the PHOBOS experiment, and discuss the results of the first physics measurement, thc pseudo rapidity densities of primary charged particles near mid rapidity in central Au + Au collisions at two different energies, √ S NN = 56 and 130 GeV. The observed densities are higher than those previously observed in any collisions, and the rate of increase between the two energies is larger than that for nucleon-nucleon collisions at comparable beam energies. This talk will describe the PHOBOS experiment, discuss the first physics measurement, and conclude with the present status of the experiment, the physics analysis and the perspectives fi the future. (Author)

A hardware overview of the RHIC LLRF platform

International Nuclear Information System (INIS)

Hayes, T.; Smith, K.S.

2011-01-01

The RHIC Low Level RF (LLRF) platform is a flexible, modular system designed around a carrier board with six XMC daughter sites. The carrier board features a Xilinx FPGA with an embedded, hard core Power PC that is remotely reconfigurable. It serves as a front end computer (FEC) that interfaces with the RHIC control system. The carrier provides high speed serial data paths to each daughter site and between daughter sites as well as four generic external fiber optic links. It also distributes low noise clocks and serial data links to all daughter sites and monitors temperature, voltage and current. To date, two XMC cards have been designed: a four channel high speed ADC and a four channel high speed DAC. The new LLRF hardware was used to replace the old RHIC LLRF system for the 2009 run. For the 2010 run, the RHIC RF system operation was dramatically changed with the introduction of accelerating both beams in a new, common cavity instead of each ring having independent cavities. The flexibility of the new system was beneficial in allowing the low level system to be adapted to support this new configuration. This hardware was also used in 2009 to provide LLRF for the newly commissioned Electron Beam Ion Source.

Spin tune dependence on closed orbit in RHIC

International Nuclear Information System (INIS)

Ptitsyn, V.; Bai, M.; Roser, T.

2010-01-01

Polarized proton beams are accelerated in RHIC to 250 GeV energy with the help of Siberian Snakes. The pair of Siberian Snakes in each RHIC ring holds the design spin tune at 1/2 to avoid polarization loss during acceleration. However, in the presence of closed orbit errors, the actual spin tune can be shifted away from the exact 1/2 value. It leads to a corresponding shift of locations of higher-order ('snake') resonances and limits the available betatron tune space. The largest closed orbit effect on the spin tune comes from the horizontal orbit angle between the two snakes. During RHIC Run in 2009 dedicated measurements with polarized proton beams were taken to verify the dependence of the spin tune on the local orbits at the Snakes. The experimental results are presented along with the comparison with analytical predictions.

Heavy nuclei, from RHIC to the cosmos

International Nuclear Information System (INIS)

Klein, Spencer R.

2003-01-01

Ultra-relativistic heavy ion collisions produce a high-temperature, thermalized system that may mimic the conditions present shortly after the big bang. This writeup will given an overview of early results from the Relativistic Heavy Ion Collider (RHIC), and discuss what we have learned about hot, strongly interacting nuclear systems. The thermal and chemical composition of the system will be discussed, along with observables that are sensitive to the early evolution of the system. I will also discuss the implications of the RHIC results for cosmic ray air showers

OVERVIEW AND STATUS OF THE STAR DETECTOR AT RHIC

International Nuclear Information System (INIS)

CHRISTIE, W.B.

1999-01-01

Presented here is the current status of the STAR Detector. STAR is one of the four detectors being constructed at the RHIC collider facility. The STAR detector is scheduled to have its first engineering run with the RHIC beams about six months from the date of this conference. The STAR project is on schedule and expects to recomplete on time

Tracking studies in eRHIC energy-recovery recirculator

Energy Technology Data Exchange (ETDEWEB)

Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brooks, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trbojevic, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-07-13

Beam and polarization tracking studies in eRHIC energy recovery electron recirculator are presented, based on a very preliminary design of the FFAG lattice. These simulations provide examples of some of the beam and spin optics aspects of the linear FFAG lattice concept and its application in eRHIC, they provide code benchmarking for synchrotron radiation and spin diffusion in addition, and pave the way towards end-to-end 6-D(phasespace)+3D(spin) tracking simulations.

Energy versus centrality dependence of the jet quenching parameter q at RHIC and LHC: a new puzzle?

Energy Technology Data Exchange (ETDEWEB)

Andres, Carlota; Armesto, Nestor; Salgado, Carlos A.; Zurita, Pia [Universidade de Santiago de Compostela, Instituto Galego de Fisica de Altas Enerxias IGFAE, Galicia (Spain); Luzum, Matthew [Universidade de Santiago de Compostela, Instituto Galego de Fisica de Altas Enerxias IGFAE, Galicia (Spain); Instituto de Fisica-Universidade de Sao Paulo, Sao Paulo (Brazil)

2016-09-15

The central goal of jet quenching studies in high-energy nuclear collisions is the characterization of those QCD medium properties that are accessible by these probes. Most of the discussion in the last years has been focused on the determination of the jet quenching parameter, q. We present here an extraction of this parameter using data of inclusive particle suppression at RHIC and LHC energies for different centralities. Our approach consists in fitting a K factor that quantifies the departure of this parameter from an ideal estimate, K ≡ q/(2ε{sup 3/4}), where q is determined by the local medium quantities as provided by hydrodynamical calculations. We find that this K factor is larger at RHIC than at the LHC, as obtained already in previous analyses, but, surprisingly, it is almost independent of the centrality of the collision. Taken at face value, the K factor would not depend on the local properties of the medium as energy density or temperature, but on global collision quantities such as the center of mass energy. This is a very intriguing, unexpected possibility for which we cannot yet provide a clear interpretation. We also comment on the limitations of the formalism that may affect this conclusion. (orig.)

RHIC spin flipper AC dipole controller

Energy Technology Data Exchange (ETDEWEB)

Oddo, P.; Bai, M.; Dawson, C.; Gassner, D.; Harvey, M.; Hayes, T.; Mernick, K.; Minty, M.; Roser, T.; Severino, F.; Smith, K.

2011-03-28

The RHIC Spin Flipper's five high-Q AC dipoles which are driven by a swept frequency waveform require precise control of phase and amplitude during the sweep. This control is achieved using FPGA based feedback controllers. Multiple feedback loops are used to and dynamically tune the magnets. The current implementation and results will be presented. Work on a new spin flipper for RHIC (Relativistic Heavy Ion Collider) incorporating multiple dynamically tuned high-Q AC-dipoles has been developed for RHIC spin-physics experiments. A spin flipper is needed to cancel systematic errors by reversing the spin direction of the two colliding beams multiple times during a store. The spin flipper system consists of four DC-dipole magnets (spin rotators) and five AC-dipole magnets. Multiple AC-dipoles are needed to localize the driven coherent betatron oscillation inside the spin flipper. Operationally the AC-dipoles form two swept frequency bumps that minimize the effect of the AC-dipole dipoles outside of the spin flipper. Both AC bumps operate at the same frequency, but are phase shifted from each other. The AC-dipoles therefore require precise control over amplitude and phase making the implementation of the AC-dipole controller the central challenge.

Experimental study of a high intensity radio-frequency cooler

Directory of Open Access Journals (Sweden)

Ramzi Boussaid

2015-07-01

Full Text Available Within the framework of the DESIR/SPIRAL-2 project, a radio-frequency quadrupole cooler named SHIRaC has been studied. SHIRaC is a key device of SPIRAL-2, designed to enhance the beam quality required by DESIR. The preliminary study and development of this device has been carried out at Laboratoire de Physique Corpusculaire de CAEN (LPC Caen, France. The goal of this paper is to present the experimental studies conducted on a SHIRaC prototype. The main peculiarity of this cooler is its efficient handling and cooling of ion beams with currents going up as high as 1  μA which has never before been achieved in any of the previous coolers. Much effort has been made lately into these studies for development of appropriate optics, vacuum and rf systems which allow cooling of beams of large emittance (∼80π  mm mrad and high current. The dependencies of SHIRaC’s transmission and the cooled beam parameters in terms of geometrical transverse emittance and the longitudinal energy spread have also been discussed. Investigation of beam purity at optimum cooling condition has also been done. Results from the experiments indicate that an emittance reduction of less than 2.5π  mm mrad and a longitudinal energy spread reduction of less than 4 eV are obtained with more than 70% of ion transmission. The emittance is at expected values whereas the energy spread is not.

Mitigation of Syngas Cooler Plugging and Fouling

Energy Technology Data Exchange (ETDEWEB)

Bockelie, Michael J. [Reaction Engineering International, Salt Lake City, UT (United States)

2015-06-29

This Final Report summarizes research performed to develop a technology to mitigate the plugging and fouling that occurs in the syngas cooler used in many Integrated Gasification Combined Cycle (IGCC) plants. The syngas cooler is a firetube heat exchanger located downstream of the gasifier. It offers high thermal efficiency, but its’ reliability has generally been lower than other process equipment in the gasification island. The buildup of ash deposits that form on the fireside surfaces in the syngas cooler (i.e., fouling) lead to reduced equipment life and increased maintenance costs. Our approach to address this problem is that fouling of the syngas cooler cannot be eliminated, but it can be better managed. The research program was funded by DOE using two budget periods: Budget Period 1 (BP1) and Budget Period 2 (BP2). The project used a combination of laboratory scale experiments, analysis of syngas cooler deposits, modeling and guidance from industry to develop a better understanding of fouling mechanisms and to develop and evaluate strategies to mitigate syngas cooler fouling and thereby improve syngas cooler performance. The work effort in BP 1 and BP 2 focused on developing a better understanding of the mechanisms that lead to syngas cooler plugging and fouling and investigating promising concepts to mitigate syngas cooler plugging and fouling. The work effort focused on the following: • analysis of syngas cooler deposits and fuels provided by an IGCC plant collaborating with this project; • performing Jet cleaning tests in the University of Utah Laminar Entrained Flow Reactor to determine the bond strength between an ash deposit to a metal plate, as well as implementing planned equipment modifications to the University of Utah Laminar Entrained Flow Reactor and the one ton per day, pressurized Pilot Scale Gasifier; • performing Computational Fluid Dynamic modeling of industrially relevant syngas cooler configurations to develop a better

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP, VOLUME 65, RHIC SPIN COLLABORATION MEETINGS XXVII, XXVIII, and XXX

International Nuclear Information System (INIS)

OGAWA, A.

2004-01-01

operational. A 10 teraflops QCDOC computer iis under construction and expected to be completed this year. This volume, 65, consists of papers from three RHIC Spin Collaboration meetings. Meeting XXVII held July 22, 2004 had 7 presentations: RHIC pp FY05 Run Preparation; AGS Cold Snake Status; PHENIX Spin Run-5 Beam Use Proposal; STAR FY05 Beam Use Request and Beyond; Update on the H-Jet; H-Jet Problems and Plans; and RHIC Polarimetry. Meeting XXVIII held September 2, 2004 had 6 presentations: Magnetic Measurement Results in the AGS Cold Snake HSD601 (a.k.a. DSM101); AGS Cold Snake Update; Preliminary Results and Interpretation of A N Measurement with pp2pp; Update on the H-Jet; Update on RHIC pC CNI Analysis; and A Few Polarimeter Studies. Meeting XXX held December 6, 2004 had 5 presentations: Polarized Proton Operations in AGS and RHIC; RHIC Status and Plan; Status and Commissioning Plans of AGS Cold Snake; Radial Polarization from RHIC CNI; and Relative Luminosity Measurement at PHENIX

RHIC: What We Have Learned So Far (434th Brookhaven Lecture)

International Nuclear Information System (INIS)

O'Brien, Edward

2008-01-01

One of the world's premiere nuclear research facilities, the Relativistic Heavy Ion Collider (RHIC) at Brookhaven Lab is just completing its eighth year of physics operation. During the past eight years, RHIC's primary physics program has emphasized the creation, observation and explanation of nuclear matter created at temperatures and densities that last existed in the universe some 13.7 billion years ago. RHIC was built to study the strong force, which holds quarks and gluons together within the nucleus of an atom, with the goal of observing a plasma of quarks and gluons freed from the atomic nucleus. The new state of matter that was created, however, was quite different. Dr. O'Brien will discuss what RHIC scientists expected versus what they discovered, and how this finding both challenges existing theory and provides an opportunity to understand the strong force better.

QCD and RHIC

International Nuclear Information System (INIS)

Kharzeev, D.

2004-01-01

In this talk I discuss recent advances in Quantum Chromo-Dynamics, in particular the progress in understanding the collective dynamics of the theory. I emphasise the significance of the RHIC program for establishing the properties of hot and dense QCD matter and for understanding the dynamics of the theory at the high parton density, strong color field frontier. Hopes and expectations for the future are discussed as well

SYNTHESIZER CONTROLLED BEAM TRANSFER FROM THE AGS TO RHIC

International Nuclear Information System (INIS)

DELONG, J.; BRENNAN, J.M.; FISCHER, W.; HAYES, T.; SMITH, K.; VALENTINO, S.

2001-01-01

To ensure minimal losses and to preserve longitudinal emittance, beam is transferred from the AGS to the RHIC bunch to bucket. This requires precision frequency and phase control for synchronization and kicker timing. The required precision is realized with a set of Direct Digital Synthesizers. Each synthesizer can be frequency and phase modulated to align the AGS bunch to the target bucket in the RHIC phase

Experience with split transition lattices at RHIC

International Nuclear Information System (INIS)

Montag, C.; Tepikian, S.; Blaskiewicz, M.; Brennan, J.M.

2010-01-01

During the acceleration process, heavy ion beams in RHIC cross the transition energy. When RHIC was colliding deuterons and gold ions during Run-8, lattices with different integer tunes were used for the two rings. This resulted in the two rings crossing transition at different times, which proved beneficial for the 'Yellow' ring, the RF system of which is slaved to the 'Blue' ring. For the symmetric gold-gold run in FY2010, lattices with different transition energies but equal tunes were implemented. We report the optics design concept as well as operational experience with this configuration.

A prototype ionization profile monitor for RHIC

International Nuclear Information System (INIS)

Connolly, R.; Cameron, P.; Ryan, W.

1997-01-01

Transverse beam profiles in the Relativistic Heavy-Ion Collider (RHIC) will be measured with ionization profile monitors (IPM's). Each IPM collects and measures the distribution of electrons in the beamline resulting from residual gas ionization during bunch passage. The electrons are swept transversely from the beamline and collected on strip anodes oriented parallel to the beam axis. At each bunch passage the charge pulses are amplified, integrated, and digitized for display as a profile histogram. A prototype detector was tested in the injection line during the RHIC Sextant Test. This paper describes the detector and gives results from the beam tests

A prototype ionization profile monitor for RHIC

Energy Technology Data Exchange (ETDEWEB)

Connolly, R.; Cameron, P.; Ryan, W. [and others

1997-07-01

Transverse beam profiles in the Relativistic Heavy-Ion Collider (RHIC) will be measured with ionization profile monitors (IPM`s). Each IPM collects and measures the distribution of electrons in the beamline resulting from residual gas ionization during bunch passage. The electrons are swept transversely from the beamline and collected on strip anodes oriented parallel to the beam axis. At each bunch passage the charge pulses are amplified, integrated, and digitized for display as a profile histogram. A prototype detector was tested in the injection line during the RHIC Sextant Test. This paper describes the detector and gives results from the beam tests.

PHOBOS at RHIC 2000

Energy Technology Data Exchange (ETDEWEB)

Back, B. B [Argonne National Laboratory (United States)] (and others)

2001-12-01

The relativistic heavy ion collider (RHIC) at Brookhaven national laboratory delivered in June 2000 the first collisions between Au nuclei at the highest center-of-mass energies achieved in a controlled environment to date. PHOBOS is one of the four experiments installed during this phase of RHIC running. This paper will describe the PHOBOS experiment, and discuss the results of the first physics measurement, the pseudo rapidity densities of primary charged particles near mid rapidity in central Au+Au collisions at two different energies, S{sub N}N{sup .}5=56 and 130 GeV. The observed densities are higher than those previously observed in any collisions, and the rate of increase between the two energies is larger than that for nucleon-nucleon collisions at comparable beam energies. This talk will describe the PHOBOS experiment, discuss the first physics measurement, and conclude with the present status of the experiment, the physics analysis and the perspectives for the future. [Spanish] El elativistic heavy ion collider (RHIC) en Brookhaven national laboratory produjo por primera vez colisiones de nucleos de oro (Au) a las energias mas altas alcanzadas en un medio ambiente controlado. PHOBOS es uno de los cuatro experimentos presentes en DIC durante su fase inicial. Este articulo describe en detalle a PHOBOS y discute los primeros resultados publicados acerca de la fisica de DIC, esto es la densidad de particulas primarias a id rapidity en colisiones centrales de Au+Au a dos diferentes energias S{sub N}N{sup .}5 =56 y 130 GeV. Las densidades observadas son mas altas que en cualquier otra experimento anterior, las densidades obtenidas son tambien mas altas que las encontradas en colisiones proton-proton a energias comparables. Este articulo tambien discute el estado actual del experimento asi como los planes para el futuro.

Design and calibration of a test facility for MLI thermal performance measurements below 80K

International Nuclear Information System (INIS)

Boroski, W.; Kunzelman, R.; Ruschman, M.; Schoo, C.

1992-04-01

The design geometry of the SSC dipole cryostat includes active thermal radiation shields operating at 80K and 20K respectively. Extensive measurements conducted in a Heat Leak Test Facility (HLTF) have been used to evaluate the thermal performance of candidate multilayer insulation (MLI) systems for the 80K thermal shield, with the present system design based upon those measurement results. With the 80K MLI geometry established, efforts have focused on measuring the performance of MLI systems near 20K. A redesign of the HLTF has produced a measurement facility capable of conducting measurements with the warm boundary fixed at 80K and the cold boundary variable from 10K to 50K. Removing the 80K shield permits measurements with a warm boundary at 300K. The 80K boundary consists of a copper shield thermally anchored to a liquid nitrogen reservoir. The cold boundary consists of a copper anchor plate whose temperature is varied through boil-off gas from a 500 liter helium supply dewar. A transfer line heat exchanger supplies the boil-off gas to the anchor plate at a constant and controlled rate. The gas, which serves as cooling gas, is routed through a copper cooling tube soldered into the anchor plate. Varying the cooling gas flow rate varies the amount of refrigeration supplied to the anchor plate, thereby determining the plate temperature. A resistance heater installed on the anchor plate is regulated by a cryogenic temperature controller to provide final temperature control. Heat leak values are measured using a heatmeter which senses heat flow as a temperature gradient across a fixed thermal impedance. Since the thermal conductivity of the thermal impedance changes with temperature, the heatmeter is calibrated at key cold boundary temperatures. Thus, the system is capable of obtaining measurement data under a variety of system conditions. 7 refs

The RHIC polarized H{sup −} ion source

Energy Technology Data Exchange (ETDEWEB)

Zelenski, A., E-mail: zelenski@bnl.gov; Atoian, G.; Raparia, D.; Ritter, J.; Steski, D. [Brookhaven National Laboratory, Upton, New York 11973 (United States)

2016-02-15

A novel polarization technique had been successfully implemented for the Relativistic Heavy Ion Collider (RHIC) polarized H{sup −} ion source upgrade to higher intensity and polarization. In this technique, a proton beam inside the high magnetic field solenoid is produced by ionization of the atomic hydrogen beam (from external source) in the He-gaseous ionizer cell. Further proton polarization is produced in the process of polarized electron capture from the optically pumped Rb vapor. The use of high-brightness primary beam and large cross sections of charge-exchange cross sections resulted in production of high intensity H{sup −} ion beam of 85% polarization. The source very reliably delivered polarized beam in the RHIC Run-2013 and Run-2015. High beam current, brightness, and polarization resulted in 75% polarization at 23 GeV out of Alternating Gradient Synchrotron (AGS) and 60%-65% beam polarization at 100-250 GeV colliding beams in RHIC.

Development of NEG Coating for RHIC Experimental Beamtubes

CERN Document Server

Weiss, Daniel; Hseuh Hsiao Chaun; Todd, Robert J

2005-01-01

As RHIC beam intensity increases beyond original scope, pressure rises in some regions have been observed. The luminosity limiting pressure rises are associated with electron multi-pacting, electron stimulated desorption and beam induced desorption. Non-Evaporable Getter (NEG) coated beampipes have been proven effective to suppress pressure rise in synchrotron radiation facilities. Standard beampipes have been NEG coated by a vendor and added to many RHIC UHV regions. BNL is developing a cylindrical magnetron sputtering system to NEG coat special beryllium beampipes installed in RHIC experimental regions. It features a hollow, liquid cooled cathode producing power density of 500W/m and deposition rate of 5000 Angstrom/hr on 7.5cm OD beampipe. The cathode, a titanium tube partially covered with zirconium and vanadium ribbons, is oriented for horizontal coating of 4m long chambers. Ribbons and magnets are arranged to provide uniform sputtering distribution and deposited NEG composition. Vacuum performance of NE...

Beam Energy Dependence of the Third Harmonic of Azimuthal Correlations in Au plus Au Collisions at RHIC

Czech Academy of Sciences Publication Activity Database

Adamczyk, L.; Bielčík, J.; Bielčíková, Jana; Chaloupka, P.; Federič, Pavol; Rusňák, Jan; Rusňáková, O.; Šimko, Miroslav; Šumbera, Michal; Vértési, Robert

2016-01-01

Roč. 116, č. 11 (2016), s. 112302 ISSN 0031-9007 R&D Projects: GA ČR GA13-20841S; GA MŠk LG15001 Institutional support: RVO:61389005 Keywords : STAR collaboration * RHIC * heavy ion collisions Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 8.462, year: 2016

Observations of Snake Resonance in RHIC

CERN Document Server

Bai, Mei; Lee, Shyh-Yuan; Lin, Fanglei; MacKay, William; Ptitsyn, Vadim; Roser, Thomas; Tepikian, Steven

2005-01-01

Siberian snakes now become essential in the polarized proton acceleration. With proper configuration of Siberian snakes, the spin precession tune of the beam becomes $\\frac{1}{2}$ which avoids all the spin depolarizing resonance. However, the enhancement of the perturbations on the spin motion can still occur when the betatron tune is near some low order fractional numbers, called snake resonances, and the beam can be depolarized when passing through the resonance. The snake resonances have been confirmed in the spin tracking calculations, and observed in RHIC with polarized proton beam. Equipped with two full Siberian snakes in each ring, RHIC provides us a perfect facility for snake resonance studies. This paper presents latest experimental results. New insights are also discussed.

Image quality and radiation dose of brain computed tomography in children: effects of decreasing tube voltage from 120 kVp to 80 kVp

International Nuclear Information System (INIS)

Park, Ji Eun; Choi, Young Hun; Cheon, Jung-Eun; Kim, Woo Sun; Kim, In-One; Cho, Hyun Suk; Ryu, Young Jin; Kim, Yu Jin

2017-01-01

Computed tomography (CT) has generated public concern associated with radiation exposure, especially for children. Lowering the tube voltage is one strategy to reduce radiation dose. To assess the image quality and radiation dose of non-enhanced brain CT scans acquired at 80 kilo-voltage peak (kVp) compared to those at 120 kVp in children. Thirty children who had undergone both 80- and 120-kVp non-enhanced brain CT were enrolled. For quantitative analysis, the mean attenuation of white and gray matter, attenuation difference, noise, signal-to-noise ratio, contrast-to-noise ratio and posterior fossa artifact index were measured. For qualitative analysis, noise, gray-white matter differentiation, artifact and overall image quality were scored. Radiation doses were evaluated by CT dose index, dose-length product and effective dose. The mean attenuations of gray and white matter and contrast-to-noise ratio were significantly increased at 80 kVp, while parameters related to image noise, i.e. noise, signal-to-noise ratio and posterior fossa artifact index were higher at 80 kVp than at 120 kVp. In qualitative analysis, 80-kVp images showed improved gray-white differentiation but more artifacts compared to 120-kVp images. Subjective image noise and overall image quality scores were similar between the two scans. Radiation dose parameters were significantly lower at 80 kVp than at 120 kVp. In pediatric non-enhanced brain CT scans, a decrease in tube voltage from 120 kVp to 80 kVp resulted in improved gray-white matter contrast, comparable image quality and decreased radiation dose. (orig.)

Image quality and radiation dose of brain computed tomography in children: effects of decreasing tube voltage from 120 kVp to 80 kVp.

Science.gov (United States)

Park, Ji Eun; Choi, Young Hun; Cheon, Jung-Eun; Kim, Woo Sun; Kim, In-One; Cho, Hyun Suk; Ryu, Young Jin; Kim, Yu Jin

2017-05-01

Computed tomography (CT) has generated public concern associated with radiation exposure, especially for children. Lowering the tube voltage is one strategy to reduce radiation dose. To assess the image quality and radiation dose of non-enhanced brain CT scans acquired at 80 kilo-voltage peak (kVp) compared to those at 120 kVp in children. Thirty children who had undergone both 80- and 120-kVp non-enhanced brain CT were enrolled. For quantitative analysis, the mean attenuation of white and gray matter, attenuation difference, noise, signal-to-noise ratio, contrast-to-noise ratio and posterior fossa artifact index were measured. For qualitative analysis, noise, gray-white matter differentiation, artifact and overall image quality were scored. Radiation doses were evaluated by CT dose index, dose-length product and effective dose. The mean attenuations of gray and white matter and contrast-to-noise ratio were significantly increased at 80 kVp, while parameters related to image noise, i.e. noise, signal-to-noise ratio and posterior fossa artifact index were higher at 80 kVp than at 120 kVp. In qualitative analysis, 80-kVp images showed improved gray-white differentiation but more artifacts compared to 120-kVp images. Subjective image noise and overall image quality scores were similar between the two scans. Radiation dose parameters were significantly lower at 80 kVp than at 120 kVp. In pediatric non-enhanced brain CT scans, a decrease in tube voltage from 120 kVp to 80 kVp resulted in improved gray-white matter contrast, comparable image quality and decreased radiation dose.

Image quality and radiation dose of brain computed tomography in children: effects of decreasing tube voltage from 120 kVp to 80 kVp

Energy Technology Data Exchange (ETDEWEB)

Park, Ji Eun [Kyung Hee University Hospital, Department of Radiology, Graduate School, Seoul (Korea, Republic of); Choi, Young Hun [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Cheon, Jung-Eun; Kim, Woo Sun; Kim, In-One [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Cho, Hyun Suk; Ryu, Young Jin; Kim, Yu Jin [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of)

2017-05-15

Computed tomography (CT) has generated public concern associated with radiation exposure, especially for children. Lowering the tube voltage is one strategy to reduce radiation dose. To assess the image quality and radiation dose of non-enhanced brain CT scans acquired at 80 kilo-voltage peak (kVp) compared to those at 120 kVp in children. Thirty children who had undergone both 80- and 120-kVp non-enhanced brain CT were enrolled. For quantitative analysis, the mean attenuation of white and gray matter, attenuation difference, noise, signal-to-noise ratio, contrast-to-noise ratio and posterior fossa artifact index were measured. For qualitative analysis, noise, gray-white matter differentiation, artifact and overall image quality were scored. Radiation doses were evaluated by CT dose index, dose-length product and effective dose. The mean attenuations of gray and white matter and contrast-to-noise ratio were significantly increased at 80 kVp, while parameters related to image noise, i.e. noise, signal-to-noise ratio and posterior fossa artifact index were higher at 80 kVp than at 120 kVp. In qualitative analysis, 80-kVp images showed improved gray-white differentiation but more artifacts compared to 120-kVp images. Subjective image noise and overall image quality scores were similar between the two scans. Radiation dose parameters were significantly lower at 80 kVp than at 120 kVp. In pediatric non-enhanced brain CT scans, a decrease in tube voltage from 120 kVp to 80 kVp resulted in improved gray-white matter contrast, comparable image quality and decreased radiation dose. (orig.)

Dynamic displacements of the RHIC dipole cold mass with injection molded composite posts during quench conditions

International Nuclear Information System (INIS)

Sondericker, J.; Wolf, L.J.

1991-02-01

The new design of the RHIC dipole magnets incorporate helium containment bellows having a convolution diameter of only 7.63 inches. The present bellows are 12.80 inches in diameter. The smaller bellows present a substantially reduced pressure area which can be expected to reduce proportionately the end force on the cold mass during a quench. But, the objection was raised that the smaller bellows would present greater obstruction to the helium flow during a quench thereby producing higher pressure differentials. This analysis was undertaken to address these assertions by predicting the dynamic displacements of the cold mass using the latest test data on the stiffness of the IMC posts, pressure-time histories acquired from the recent full cell tests of RHIC magnets, and the dimensions of the new expansion joints. The analysis treated the cold mass as an elastic body having a saggittal curvature. The technique of normal mode expansion of a lumped-parameter system was used to obtain the results and conclusions reported herein

RHIC injection kicker impedance

International Nuclear Information System (INIS)

Mane, V.; Peggs, S.; Trbojevic, D.; Zhang, W.

1995-01-01

The longitudinal impedance of the RHIC injection kicker is measured using the wire method up to a frequency of 3 GHz. The mismatch between the 50 ohm cable and the wire and pipe system is calibrated using the TRL calibration algorithm. Various methods of reducing the impedance, such as coated ceramic pipe and copper strips are investigated

Thermoelectric coolers as power generators

International Nuclear Information System (INIS)

Burke, E.J.; Buist, R.J.

1984-01-01

There are many applications where thermoelectric (TE) coolers can be used effectively as power generators. The literature available on this subject is scarce and very limited in scope. This paper describes the configuration, capability, limitations and performance of TE coolers to be used as power generators. Also presented are performance curves enabling the user to design the optimum TE module for any given power generation application

Polarized proton parameters for the 2015 PP-on-Au setup in RHIC

Energy Technology Data Exchange (ETDEWEB)

Gardner, C. J. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-08-25

Values are given for RHIC circumference shifts due to snakes for various situations. Relevant parameters are tabulated for polarized protons (PP) in the booster and in AGS and RHIC for PP-on-Au stores.

Polarized proton parameters for the 2015 PP-on-Aluminum setup in RHIC

Energy Technology Data Exchange (ETDEWEB)

Gardner, C. J. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-10-02

Values are given for RHIC circumference shifts due to snakes for various situations. Relevant parameters are tabulated for polarized protons (PP) in the booster and in AGS and RHIC for PP-on-Aluminum stores.

Heat driven thermoacoustic cooler based on traveling-standing wave

International Nuclear Information System (INIS)

Kang Huifang; Zhou Gang; Li Qing

2010-01-01

This paper presents a heat driven thermoacoustic cooler system without any moving part. It consists of a thermoacoustic engine and a thermoacoustic cooler, and the former is the driving source of the latter. Both the engine and the cooler are located in one loop tube coupled with a resonator tube, and the acoustic power produced by the engine is used to drive the cooler directly. Both regenerators of the engine and the cooler are located in the near region of the pressure antinode, and operate in traveling-standing wave phase region. In the engine's regenerator, both components of the standing wave and the traveling wave realize the conversion from heat to acoustic energy. This improves the efficiency of the engine. In the cooler's regenerator, both components of the traveling wave and the standing wave pump heat from the cold end. This improves the efficiency of the cooler. At the operating point with a mean pressure of 22 bar, helium as working gas, a frequency of 234 Hz, and a heating power of 300 W, the experimental cooler provides a no-load temperature of -30 deg. C and a cooling power of 40 W at the cooling temperature of 0 deg. C. The total length of this cooler system is less than 1 m, which shows a good prospect for the domestic cooler system in room-temperature cooling such as food refrigeration and air-conditioning.

Experts dismiss doomsday scenarios for RHIC

CERN Multimedia

Levi, B G

2000-01-01

A panel of particle physicists examining the possibility that operation of RHIC could generate blackholes or 'strangelets' which would consume ordinary matter, have declared that such scenarios are 'firmly excluded' (1 p).

Conceptual design of the Relativistic Heavy Ion Collider [RHIC

International Nuclear Information System (INIS)

1989-05-01

In August 1984 Brookhaven National Laboratory submitted a proposal for the construction of a Relativistic Heavy Ion Collider (RHIC) to the US Department of Energy. A Conceptual Design Report for the RHIC facility was completed in May 1986 after detailed reviews of the machine design, and of the requirements of the physics research program. Since that time an extensive R ampersand D program has been initiated and considerable work has been carried out to refine the design and specification of the major accelerator components, as well as the needs for research detectors, and to prepare the project for construction. This document is an update of the Conceptual Design Report, incorporating the results of work carried out since the beginning of Fiscal Year 1987 when a formal R ampersand D program for the RHIC project funded by DOE was initiated

The RHIC/AGS Online Model Environment: Design and Overview

International Nuclear Information System (INIS)

Satogata, T.; Brown, K.; Pilat, F.; Tafti Alai, A.; Tepikian, S.; Vanzeijtz

1999-01-01

An integrated online modeling environment is currently under development for use by AGS and RHIC physicists and commissioners. This environment combines the modeling efforts of both groups in a CDEV[1] client-server design, providing access to expected machine optics and physics parameters based on live and design machine settings. An abstract modeling interface has been designed as a set of adapters[2] around core computational modeling engines such as MAD and UAL/Teapot++[3]. This approach allows us to leverage existing survey, lattice, and magnet infrastructure, as well as easily incorporate new model engine developments. This paper describes the architecture of the RHIC/AGS modeling environment, including the application interface through CDEV and general tools for graphical interaction with the model using Tcl/Tk. Separate papers at this conference address the specifics of implementation and modeling experience for AGS and RHIC

Opportunities for Polarized He-3 in RHIC and EIC

Energy Technology Data Exchange (ETDEWEB)

Aschenauer E.; Deshpande, A.; Fischer, W.; Derbenev, S.; Milner, R.; Roser, T.; Zelenski, A.

2011-10-01

The workshop on opportunities for polarized He-3 in RHIC and EIC was targeted at finding practical ways of implementing and using polarized He-3 beams. Polarized He-3 beams will provide the unique opportunity for first measurements, i.e, to a full quark flavor separation measuring single spin asymmetries for p{sup +}, p{sup -} and p{sup 0} in hadron-hadron collisions. In electron ion collisions the combination of data recorded with polarized electron proton/He-3 beams allows to determine the quark flavor separated helicity and transverse momentum distributions. The workshop had sessions on polarized He-3 sources, the physics of colliding polarized He-3 beams, polarimetry, and beam acceleration in the AGS Booster, AGS, RHIC, and ELIC. The material presented at the workshop will allow making plans for the implementation of polarized He-3 beams in RHIC.

PROPOSAL FOR AN EBIS BASED RHIC PREINJECTOR.

Energy Technology Data Exchange (ETDEWEB)

ALESSI,J.G.; BEEBE,E.; KPONOU,A.; PIKIN,A.; PRELEC,K.; RAPARIA,D.; RITTER,J.; ZHANG,S.Y.

2000-11-06

A proposed new heavy ion preinjector for RHIC is described. The progress made at BNL on the development of an Electron Beam Ion Source (EBIS) has increased our confidence that one can build a preinjector meeting RHIC requirements using an EBIS producing intermediate charge state heavy ions. A new RFQ and Linac will be required to accelerate beams from this source to an energy sufficient for injection into the AGS Booster. These are both straightforward devices, very similar to ones already in operation at other laboratories. Injection into the Booster will occur at the same location as the existing heavy ion injection from the Tandem Van de Graaff.

PROPOSAL FOR AN EBIS-BASED RHIC PREINJECTOR

International Nuclear Information System (INIS)

ALESSI, J.G.; BEEBE, E.; KPONOU, A.; PIKIN, A.; PRELEC, K.; RAPARIA, D.; RITTER, J.; ZHANG, S.Y.

2000-01-01

A proposed new heavy ion preinjector for RHIC is described. The progress made at BNL on the development of an Electron Beam Ion Source (EBIS) has increased our confidence that one can build a preinjector meeting RHIC requirements using an EBIS producing intermediate charge state heavy ions. A new RFQ and Linac will be required to accelerate beams from this source to an energy sufficient for injection into the AGS Booster. These are both straightforward devices, very similar to ones already in operation at other laboratories. Injection into the Booster will occur at the same location as the existing heavy ion injection from the Tandem Van de Graaff

Results from the Cooler and Lead Tests

International Nuclear Information System (INIS)

Green, Michael A.

2010-01-01

The report presents the results of testing MICE spectrometer magnet current leads on a test apparatus that combines both the copper leads and the high temperature superconducting (HTS) leads with a single Cryomech PT415 cooler and liquid helium tank. The current is carried through the copper leads from 300 K to the top of the HTS leads. The current is then carried through the HTS leads to a feed-through from the vacuum space to the inside of a liquid helium tank. The experiment allows one to measure the performance of both cooler stages along with the performance of the leads. While the leads were powered we measured the voltage drops through the copper leads, through the HTS leads, through spliced to the feed-through, through the feed-through and through the low-temperature superconducting loop that connects one lead to the other. Measurements were made using the leads that were used in spectrometer magnet 1A and spectrometer magnet 2A. These are the same leads that were used for Superbend and Venus magnets at LBNL. The IL/A for these leads was 5.2 x 10 6 m -1 . The leads turned out to be too long. The same measurements were made using the leads that were installed in magnet 2B. The magnet 2B leads had an IL/A of 3.3 x 10 6 A m -1 . This report discusses the cooler performance and the measured electrical performance of the lead circuit that contains the copper leads and the superconducting leads. All of the HTS leads that were installed in magnet 2B were current tested using this apparatus.

RFQ Cooler and Buncher (and beam line section associated)

CERN Document Server

Podadera-Aliseda, I

2003-01-01

Developing a new RFQ cooler and buncher for ISOLDE. Such a device combines an energy loss in buffer gas atom-ion collisions with confinement provided by RF-field in transverse plane. Optional confinement in longitudinal direction is provided by static potential dwell. Then, an improvement of the beam line is achieved for all the experiments at ISOLDE. The RFQ operates inside a high voltage cage of 60 kV, and with a system of turbomulecular pumps both to keep the high vacuum before/after the RFQ and to keep a low pressure (around 0,1 mbar) inside the RFQ. The project is to be thought not only as a mechanical design and construction project, unless as a project of research and development, since it is about improving (operationally and technically) the existing RFQ cooler and buncher placed around the world. Due to ion optical reasons whole beam line section has to be redesigned and constructed as a part of this project.

Thermal and prompt photons at RHIC and the LHC

Energy Technology Data Exchange (ETDEWEB)

Paquet, Jean-François [Department of Physics & Astronomy, Stony Brook University, Stony Brook, NY 11794 (United States); Department of Physics, McGill University, 3600 University Street, Montreal, Quebec, H3A2T8 (Canada); Shen, Chun [Department of Physics, McGill University, 3600 University Street, Montreal, Quebec, H3A2T8 (Canada); Denicol, Gabriel [Department of Physics, McGill University, 3600 University Street, Montreal, Quebec, H3A2T8 (Canada); Physics Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Luzum, Matthew [Universidade de Santiago de Compostela, E-15706 Santiago de Compostela, Galicia-Spain (Spain); Universidade de São Paulo, Rua do Matão Travessa R, no. 187, 05508-090, Cidade Universitária, São Paulo (Brazil); Schenke, Björn [Physics Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Jeon, Sangyong; Gale, Charles [Department of Physics, McGill University, 3600 University Street, Montreal, Quebec, H3A2T8 (Canada)

2016-12-15

Thermal and prompt photon production in heavy ion collisions is evaluated and compared with measurements from both RHIC and the LHC. An event-by-event hydrodynamical model of heavy ion collisions that includes shear and bulk viscosities is used, along with up-to-date photon emission rates. Larger tension with measurements is observed at RHIC than at the LHC. The center-of-mass energy and centrality dependence of thermal and prompt photons is investigated.

Beam-beam collisions and crossing angles in RHIC

International Nuclear Information System (INIS)

Peggs, S.

1999-01-01

This paper evaluates the strength of head on and parasitic beam-beam collisions in RHIC when the crossing angle is zero. A non-zero crossing angle is not required in normal operation with 120 bunches, thanks to the early separation of the two beams. The RHIC lattice is shown to easily accommodate even conservatively large crossing angles, for example in beam dynamics studies, or in future operational upgrades to as many as 360 bunches per ring. A modest loss in luminosity is incurred when gold ions collide at an angle after 10 hours of storage

Exploring new frontiers in nuclear and particle physics with the STAR detector at RHIC

International Nuclear Information System (INIS)

Hallman, T.J.

1996-01-01

The Solenoidal Tracker At RHIC (STAR) is a large acceptance collider detector scheduled to begin operation at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory in the fall of 1999. In the sections which follow, details of the STAR detector and physics program, as well as the status of the RHIC construction project will be presented

Cryogenic systems for proof of the principle experiment of coherent electron cooling at RHIC

Energy Technology Data Exchange (ETDEWEB)

Huang, Yuenian; Belomestnykh, Sergey; Brutus, Jean Clifford; Lederle, Dewey; Orfin, Paul; Skaritka, John; Soria, Victor; Tallerico, Thomas; Than, Roberto [Collider Accelerator Department, Brookhaven National Laboratory, Upton, NY 11973 (United States)

2014-01-29

The Coherent electron Cooling (CeC) Proof of Principle (PoP) experiment is proposed to be installed in the Relativistic Heavy Ion Collider (RHIC) to demonstrate proton and ion beam cooling with this new technique that may increase the beam luminosity in certain cases, by as much as tenfold. Within the scope of this project, a 112 MHz, 2MeV Superconducting Radio Frequency (SRF) electron gun and a 704 MHz 20MeV 5-cell SRF cavity will be installed at IP2 in the RHIC ring. The superconducting RF electron gun will be cooled in a liquid helium bath at 4.4 K. The 704 MHz 5-cell SRF cavity will be cooled in a super-fluid helium bath at 2.0 K. This paper discusses the cryogenic systems designed for both cavities. For the 112 MHz cavity cryogenic system, a condenser/boiler heat exchanger is used to isolate the cavity helium bath from pressure pulses and microphonics noise sources. For the 704 MHz 5-cell SRF cavity, a heat exchanger is also used to isolate the SRF cavity helium bath from noise sources in the sub-atmospheric pumping system operating at room temperature. Detailed designs, thermal analyses and discussions for both systems will be presented in this paper.

Report of the stochastic cooling subgroup of the RHIC workshop

International Nuclear Information System (INIS)

Boussard, D.; Claus, J.; DiMassa, G.; Marriner, J.; Milutinovic, J.; Shafer, R.

1988-01-01

We have considered the possibility of stochastic cooling of beams for the RHIC collider. Similar studies have been carried out previously for RHIC and other bunched beam proton machines. The major motivation for cooling at RHIC is to stabilize the growth from intrabeam scattering. We find that cooling rates of the order of 500 sec are theoretically possible for beams of gold ions with γ = 100 if a cooling bandwidth of 10 GHz is used. However, the amount of microwave power which is required is large for momentum cooling and probably not practical. Considerably less power is required for slower rates. We believe that cooling times of 5000 sec for momentum cooling and 1000 sec for betatron cooling might be possible. 5 refs

Development of a hybrid cooler; Udvikling af hybridkoeler

Energy Technology Data Exchange (ETDEWEB)

Schneider, P.; Toftegaard, R.; Weinkauff Kristoffersen, J. [Teknologisk Institut, Aarhus (Denmark); Juel Skovrup, M. [IPU, Kgs. Lyngby (Denmark); Ibsen, C. [VP Industries, Lem (Denmark)

2013-04-15

The project aims to develop a hybrid cooler which acts as a dry cooler in the winter and as cooling tower in summer. Energy consumption for cooling systems with a dry cooler and a cooling tower, respectively, is comparable in the winter months. This phase 1 of the project shows that improvements of 50-100% on the performance of a hybrid cooler can be achieved as compared to a dry cooler. The improvement is achieved by humidifying the air with recirculated water through nozzles so that the air temperature decreases from the dry temperature to the wet temperature, and that the dry cooler surface is humidified with a film of water, which increases the heat transfer coefficient considerably compared to a dry surface. The experiments showed that a humidifier system cannot be used without further action. At face velocities less than 5 m/s the humidification does not yield any improvement, and in some cases the heat transfer in a standard dry cooler is decreased. This is due to entrainment of not fully vaporized droplets which are deposited between the dry cooler fins and form bridges that block parts of the cooler. By modifying the surface characteristics with a coating, it will be possible to drain the water away so that no bridges are formed. The company Accoat, which makes special surfaces, will therefore be associated to phase 2 of the project. Another aspect that was evident in the tests, is the formation of biofilm on the heat exchanger surface, which can reduce performance by up to 25%. Biofilm can be prevented by treating the feed water, and therefore Danish Clean Water A/S associated to phase 2 of the project, as they produce water purification systems for biofouling decomposition. (LN)

First turn around strategy for RHIC

International Nuclear Information System (INIS)

Milutinovic, J.; Ruggiero, A.G.

1991-01-01

The authors present a strategy for achieving the so-called first turn around in RHIC. The strategy is based on the same method proposed to correct a distorted closed orbit in RHIC, i.e. on a generalization of the local three-bump method. They found out that the method is very effective in passing the beam through a non-ideal, insufficiently known, machine. The perturbed lattice was generated by the code PATRIS, which was also adapted to control the newly developed software. In ten distributions of errors the software was capable of passing the beam through in 2-3 injection attempts, at full sextupole strength. It was also determined that once the beam makes the first turn around and all the correctors are energized, it stays in the machine for at least several hundred turns

Update to the RHIC Letter of Intent for an experiment on particle and jet production at midrapidity

International Nuclear Information System (INIS)

1991-07-01

This document is an Update to the Letter of Intent (LOI) submitted by this collaboration in September 1990 proposing a large acceptance solenoidal tracking experiment. Since that time the collaboration has chosen the name STAR, representing Solenoidal Tracker At RHIC. The physics interests of the STAR collaboration and the goals of the experiment are described in the original LOI. Since submission of the LOI, several changes have been made in the design of the experiment motivated by the desire to expand pseudorapidity coverage for complete event characterization and by the necessity to achieve cost reduction. The major changes are: Expansion of pseudorapidity coverage to |η| < 4.5 by the addition of tracking chambers external to the magnet; reduction in the number of time-of-flight channels from 100K to 10K; staging implementation of hadronic calorimetry while using tracking and electromagnetic calorimetry to extract parton physics in the initial configuration; reduction in the cost per channel of Time Projection Chamber (TPC) electronics through continued TPC electronics R ampersand D supported from RHIC funds; and a change in the Silicon Vertex Tracker (SVT) technique to the use of silicon drift chambers. These changes and the status of ongoing R ampersand D programs to optimize the design and performance of the STAR experiment will be presented. In terms of detector performance it will be demonstrated that the space charge loading of the TPC is negligible and that the STAR experiment can operate at the highest RHIC luminosities. A summary of the detector systems is presented in this paper

ERL with non-scaling fixed field alternating gradient lattice for eRHIC

Energy Technology Data Exchange (ETDEWEB)

Trbojevic, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brooks, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hao, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Litvinenko, V. N. [Brookhaven National Lab. (BNL), Upton, NY (United States); Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Thieberger, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-05-03

The proposed eRHIC electron-hadron collider uses a "non-scaling FFAG" (NS-FFAG) lattice to recirculate 16 turns of different energy through just two beam lines located in the RHIC tunnel. This paper presents lattices for these two FFAGs that are optimized for low magnet field and to minimize total synchrotron radiation across the energy range. The higher number of recirculations in the FFAG allows a shorter linac (1.322GeV) to be used, drastically reducing cost, while still achieving a 21.2 GeV maximum energy to collide with one of the existing RHIC hadron rings at up to 250GeV. eRHIC uses many cost-saving measures in addition to the FFAG: the linac operates in energy recovery mode, so the beams also decelerate via the same FFAG loops and energy is recovered from the interacted beam. All magnets will be constructed from NdFeB permanent magnet material, meaning chillers and large magnet power supplies are not needed. This paper also describes a small prototype ERL-FFAG accelerator that will test all of these technologies in combination to reduce technical risk for eRHIC.

Workshop on the RHIC performance

Energy Technology Data Exchange (ETDEWEB)

Khiari, F.; Milutinovic, J.; Ratti, A.; Rhoades-Brown, M.J. (eds.)

1988-07-01

The most recent conceptual design manual for the Relativistic Heavy Ion Collider (RHIC) at Brookhaven was published in May 1986 (BNL 51932). The purpose of this workshop was to review the design specifications in this RHIC reference manual, and to discuss in detail possible improvements in machine performance by addressing four main areas. These areas are beam-beam interactions, stochastic cooling, rf and bunch instabilities. The contents of this proceedings are as follows. Following an overview of the workshop, in which the motivation and goals are discussed in detail, transcripts of the first day talks are given. Many of these transcripts are copies of the original transparencies presented at the meeting. The following four sections contain contributed papers, that resulted from discussions at the workshop within each of the four working groups. In addition, there is a group summary for each of the four working groups at the beginning of each section. Finally, a list of participants is given.

Tau electron atoms at RHIC

International Nuclear Information System (INIS)

Weiss, M.S.

1985-01-01

An amusement ancillary to the proposed quark-gluon plasma production hypothesized from a relativistic heavy ion collider (RHIC is a sufficient quantity of tau electrons to potentially admit the study of its exotic atoms. In this paper the given wealth of nuclear phenomena is derived from muonic atoms assume a tau atom is more forthcoming of information due to the lower orbits entirely contained within the nucleus. It is the purpose of this brief note to discuss the production mechanism at a RHIC and to delineate some of the more obvious properties of the tau atom. As in the case of the mu, more exotic phenomena derived from resonance ''accidents'' with nuclear transitions takes place, but it would be presumptions to discuss them at this time. Given the complete containment in nuclear matter of the tau lepton in its innermost atomic orbits. An experiment performed with such an exotic species results in the measurement of its lifetime

First results from RHIC-PHENIX

CERN Document Server

Ghosh, T K; Adler, S S; Ajitanand, N N; Akiba, Y; Alexander, J; Aphecetche, L; Arai, Y; Aronson, S H; Averbeck, R; Awes, T C; Barish, K N; Barnes, P D; Barrette, J; Bassalleck, B; Bathe, S; Baublis, V; Bazilevsky, A; Belikov, S V; Bellaiche, F G; Belyaev, S T; Bennett, M J; Berdnikov, Yu A; Botelho, S S; Brooks, M L; Brown, D S; Bruner, N L; Bucher, D; Büsching, H; Bunce, G M; Burward-Hoy, J M; Butsyk, S; Carey, T A; Chand, P; Chang, J; Chang, W C; Chavez, L L; Chernichenko, S K; Chi, C Y; Chiba, J; Chiu, M; Choudhury, R K; Christ, T; Chujo, T; Chung, M S; Chung, P; Cianciolo, V; Cole, B A; D'Enterria, D G; Dávid, G; Delagrange, H; Denisov, A; Deshpande, A A; Desmond, E J; Dietzsch, O; Dinesh, B V; Drees, A; Durum, A A; Dutta, D; Ebisu, K; Efremenko, Yu V; Chenawi, K E; En-Yo, H; Esumi, S C; Ewell, L A; Ferdousi, T; Fields, D E; Fokin, S L; Fraenkel, Zeev; Franz, A; Frawley, A D; Fung, S Y; Garpman, S; Ghosh, T K; Glenn, A; Godoi, A L; Goto, Y; Greene, S V; Grosse-Perdekamp, M; Gupta, S K; Guryn, W; Gustafsson, Hans Åke; Haggerty, J S; Hamagaki, H; Hansen, A G; Hara, H; Hartouni, E P; Havano, R; Hayashi, N; He, X; Hemmick, T K; Heuser, J M; Hill, J C; Ho, D S; Homma, K; Hong, B; Hoover, A; Ichihara, T; Imai, K; Ippolitov, M S; Ishihara, M; Jacak, B V; Jang, W Y; Jia, J; Johnson, B M; Johnson, S C; Joo, K S; Kametani, S; Kang, J H; Kann, M; Kapoor, S S; Kelly, S; Khachaturov, B A; Khanzadeev, A V; Kikuchi, J; Kim, D J; Kim, H J; Kim, S Y; Kim, Y G; Kinnison, W W; Kistenev, E P; Kiyomichi, A; Klein-Bösing, C; Klinksiek, S A; Kochenda, L M; Kochetkov, D; Kochetkov, V; Köhler, D; Kohama, T; Kozlov, A; Kroon, P J; Kurita, K; Kweon, M J; Kwon, Y; Kyle, G S; Lacey, R A; Lajoie, J G; Lauret, J; Lebedev, A; Lee, D M; Leitch, M J; Li, X H; Li, Z; Lim, D J; Liu, M X; Liu, X; Liu, Z; Maguire, C F; Mahon, J; Makdisi, Y I; Man'ko, V I; Mao, Y; Mark, S K; Markacs, S; Martínez, G; Marx, M D; Massaike, A; Matathias, F; Matsumoto, T; McGaughey, P L; Melnikov, E A; Merschmeyer, M; Messer, F; Messer, M; Miake, Y; Miller, T E; Milov, A; Mioduszewski, S; Mischke, R E; Mishra, G C; Mitchell, J T; Mohanty, A K; Morrison, D P; Moss, J M; Muhlbacher, F; Muniruzzaman, M; Murata, J; Nagamiya, S; Nagasaka, Y; Nagle, J L; Nakada, Y; Nandi, B K; Newby, J; Nikkinen, L; Nilsson, P O; Nishimura, S; Nyanin, A S; Nystrand, J; O'Brien, E; Ogilvie, C A; Ohnishi, H; Ojha, I D; Ono, M; Onuchin, V A; Oskarsson, A; Österman, L; Otterlund, I; Oyama, K; Paffrath, L; Palounek, A P T; Pantuev, V S; Papavassiliou, V; Pate, S F; Peitzmann, Thomas; Petridis, A N; Pinkenburg, C H; Pisani, R P; Pitukhin, P; Plasil, F; Pollack, M E; Pope, K; Purschke, M L; Ravinovich, I; Read, K F; Reygers, K; Riabov, V; Riabov, Y; Rosati, M; Rose, A A; Ryu, S S; Saitô, N; Sakaguchi, A; Sakaguchi, T; Sako, H; Sakuma, T; Samsonov, V; Sangster, T C; Santo, R; Sato, H D; Sato, S; Sawada, S; Schlei, B R; Schutz, Y; Semenov, V; Seto, R; Shea, T K; Shein, I; Shibata, T A; Shigaki, K; Shiina, T; Shin, Y H; Sibiryak, Yu; Silvermyr, D; Sim, K S; Simon-Gillo, J; Singh, C P; Singh, V; Sivertz, M; Soldatov, A; Soltz, R A; Sørensen, S; Stankus, P W; Starinsky, N; Steinberg, P; Stenlund, E; Ster, A; Stoll, S P; Sugioka, M; Sugitate, T; Sullivan, J P; Sumi, Y; Sun, Z; Suzuki, M; Takagui, E M; Taketani, A; Tamai, M; Tanaka, Y; Taniguchi, E; Tannenbaum, M J; Thomas, J; Thomas, J H; Thomas, T L; Tian, W; Tojo, J; Torii, H A; Towell, R S; Tserruya, Itzhak; Tsuruoke, H; Tsvetkov, A A; Tuli, S K; Tydesjo, H; Tyurin, N; Ushiroda, T; van Hecke, H; Velissaris, C; Velkovska, J; Velkovsky, M; Vingradov, A A; Volkov, M A; Vorobyov, A A; Vznuzdaev, E A; Wang, H; Watanabe, Y; White, S N; Witzig, C; Wohn, F K; Woody, C L; Xie, W; Yagi, K; Yokkaichi, S; Young, G R; Yushmanov, I E; Zajc, W A; Zhang, Z; Zhou, S

2001-01-01

The PHENIX experiment consists of a large detector system located at the newly commissioned Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Laboratory. The primary goal of the PHENIX experiment is to look for signatures of the QCD prediction of a deconfined high-energy-density phase of nuclear matter and the quark gluon plasma. PHENIX started taking data for Au+Au collisions at square root (s/sub NN/)=130 GeV in June 2000. The signals from the beam-beam counter (BBC) and zero degree calorimeter (ZDC) are used to determine the centrality of the collision. A Glauber model reproduces the ZDC spectrum reasonably well to determine the participants in a collision. The charged particle multiplicity distribution from the first PHENIX paper is compared with the other RHIC experiment and the CERN and SPS results. Transverse momentum of photons are measured in the electro-magnetic calorimeter (EMCal) and preliminary results an presented. Particle identification is made by a time-of-flight (TOF) detecto...

Polarized proton acceleration program at the AGS and RHIC

International Nuclear Information System (INIS)

Lee, Y.Y.

1995-01-01

Presented is an overview of the program for acceleration of polarized protons in the AGS and their injection into the RHIC collider. The problem of depolarizing resonances in strong focusing circulator accelerators is discussed. The intrinsic resonances are jumped over by the fast tune jump, and a partial Siberian Snake is used to compensate for over forty imperfection resonances in the AGS. Two sets of full Siberian Snake and spin rotators will be employed in RHIC

Laser ion source with long pulse width for RHIC-EBIS

International Nuclear Information System (INIS)

Kondo, K.; Kanesue, T.; Okamura, M.

2011-01-01

The Electron Beam Ion Source (EBIS) at Brookhaven National Laboratory is a new heavy ion-projector for RHIC and NASA Space Radiation Laboratory. Laser Ion Source (LIS) with solenoid can supply many kinds of ion from solid targets and is suitable for long pulse length with low current as ion provider for RHIC-EBIS. In order to understand a plasma behavior for fringe field of solenoid, we measure current, pulse width and total ion charges by a new ion probe. The experimental result indicates that the solenoid confines the laser ablation plasma transversely. Laser ion source needs long pulse length with limited current as primary ion provider for RHIC-EBIS. New ion probe can measure current distribution for the radial positions along z axis. The beam pulse length is not effected by magnetic field strength. However, the currents and charges decay with the distance from the end of solenoid. These results indicate that solenoid field has important role for plasma confinement not longitudinally but transversely and solenoid is able to have long pulse length with sufficient total ion charges. Moreover, the results are useful for a design of the extraction system for RHIC-EBIS.

Criticality safety study of shutdown diffusion cascade coolers

International Nuclear Information System (INIS)

Paschal, L.S.; Basoglu, B.; Bentley, C.L.; Dunn, M.E.

1996-01-01

Gaseous diffusion plants use cascade coolers in the production of highly enriched uranium (HEU) to remove heat from the enriched stream of UF 6 . The cascade coolers operate like shell and tube heat exchangers with the UF 6 on the shell side and Freon on the tube side. Recirculating cooling water (RCW) in condensers is used to cool the Freon. A criticality safety analysis was previously performed for cascade coolers during normal operation. The purpose of this paper is to evaluate several different hypothetical accidents regarding RCW ingress into the cooler to determine whether criticality safety concerns exist

RHIC ABORT KICKER WITH REDUCED COUPLING IMPEDANCE

International Nuclear Information System (INIS)

HAHN, H.; DAVINO, D.

2002-01-01

Kicker magnets typically represent the most important contributors to the transverse impedance budget of accelerators and storage rings. Methods of reducing the impedance value of the SNS extraction kicker presently under construction and, in view of a future performance upgrade, that of the RHIC abort kicker have been thoroughly studied at this laboratory. In this paper, the investigation of a potential improvement from using ferrite different from the BNL standard CMD5005 is reported. Permeability measurements of several ferrite types have been performed. Measurements on two kicker magnets using CMD5005 and C2050 suggest that the impedance of a magnet without external resistive damping, such as the RHIC abort kicker, would benefit

Helium pressures in RHIC vacuum cryostats and relief valve requirements from magnet cooling line failure

Energy Technology Data Exchange (ETDEWEB)

Liaw, C.J.; Than, Y.; Tuozzolo, J.

2011-03-28

A catastrophic failure of the RHIC magnet cooling lines, similar to the LHC superconducting bus failure incident, would pressurize the insulating vacuum in the magnet and transfer line cryostats. Insufficient relief valves on the cryostats could cause a structural failure. A SINDA/FLUINT{reg_sign} model, which simulated the 4.5K/4 atm helium flowing through the magnet cooling system distribution lines, then through a line break into the vacuum cryostat and discharging via the reliefs into the RHIC tunnel, had been developed to calculate the helium pressure inside the cryostat. Arc flash energy deposition and heat load from the ambient temperature cryostat surfaces were included in the simulations. Three typical areas: the sextant arc, the Triplet/DX/D0 magnets, and the injection area, had been analyzed. Existing relief valve sizes were reviewed to make sure that the maximum stresses, caused by the calculated maximum pressures inside the cryostats, did not exceed the allowable stresses, based on the ASME Code B31.3 and ANSYS results. The conclusions are as follows: (1) The S/F simulation results show that the highest internal pressure in the cryostats, due to the magnet line failure, is {approx}37 psig (255115 Pa); (2) Based on the simulation, the temperature on the cryostat chamber, INJ Q8-Q9, could drop to 228 K, which is lower than the material minimum design temperature allowed by the Code; (3) Based on the ASME Code and ANSYS results, the reliefs on all the cryostats inside the RHIC tunnel are adequate to protect the vacuum chambers when the magnet cooling lines fail; and (4) In addition to the pressure loading, the thermal deformations, due to the temperature decrease on the cryostat chambers, could also cause a high stress on the chamber, if not properly supported.

Helium pressures in RHIC vacuum cryostats and relief valve requirements from magnet cooling line failure

International Nuclear Information System (INIS)

Liaw, C.J.; Than, Y.; Tuozzolo, J.

2011-01-01

A catastrophic failure of the RHIC magnet cooling lines, similar to the LHC superconducting bus failure incident, would pressurize the insulating vacuum in the magnet and transfer line cryostats. Insufficient relief valves on the cryostats could cause a structural failure. A SINDA/FLUINT(reg s ign) model, which simulated the 4.5K/4 atm helium flowing through the magnet cooling system distribution lines, then through a line break into the vacuum cryostat and discharging via the reliefs into the RHIC tunnel, had been developed to calculate the helium pressure inside the cryostat. Arc flash energy deposition and heat load from the ambient temperature cryostat surfaces were included in the simulations. Three typical areas: the sextant arc, the Triplet/DX/D0 magnets, and the injection area, had been analyzed. Existing relief valve sizes were reviewed to make sure that the maximum stresses, caused by the calculated maximum pressures inside the cryostats, did not exceed the allowable stresses, based on the ASME Code B31.3 and ANSYS results. The conclusions are as follows: (1) The S/F simulation results show that the highest internal pressure in the cryostats, due to the magnet line failure, is ∼37 psig (255115 Pa); (2) Based on the simulation, the temperature on the cryostat chamber, INJ Q8-Q9, could drop to 228 K, which is lower than the material minimum design temperature allowed by the Code; (3) Based on the ASME Code and ANSYS results, the reliefs on all the cryostats inside the RHIC tunnel are adequate to protect the vacuum chambers when the magnet cooling lines fail; and (4) In addition to the pressure loading, the thermal deformations, due to the temperature decrease on the cryostat chambers, could also cause a high stress on the chamber, if not properly supported.

Measurement of the Transverse Single-Spin Asymmetry in p up arrow plus p -> W-+/-/Z(0) at RHIC

Czech Academy of Sciences Publication Activity Database

Adamczyk, L.; Bielčík, J.; Bielčíková, Jana; Chaloupka, P.; Federič, Pavol; Rusňák, Jan; Rusňáková, O.; Šimko, Miroslav; Šumbera, Michal; Vértési, Robert

2016-01-01

Roč. 116, č. 13 (2016), s. 132301 ISSN 0031-9007 R&D Projects: GA ČR GA13-20841S; GA MŠk LG15001 Institutional support: RVO:61389005 Keywords : STAR collaboration * RHIC * deep inelastic lepton-proton scattering Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 8.462, year: 2016

TORE-SUPRA: design of thermal radiation shield at 80 K

International Nuclear Information System (INIS)

Aymar, R.; Cordier, J.J.; Deschamps, P.; Gauthier, A.; Perin, J.P.

1982-09-01

The TORE-SUPRA superconducting toroidal magnet operating at liquid helium temperature, must be protected against thermal radiation from the vessels. For this purpose, stainless steel heat shields, cooled at 80 K, are positioned between coil casings at 4.5 K and the vessels, and constitute a double stiff toroid which completely surrounds the magnet. Mockups have been manufactured to study their design and operating problems. Calculations have also been made to analyse the mechanical behaviour of these shields

Report on EBIS studies for a RHIC preinjector

International Nuclear Information System (INIS)

Beebe, E.; Hershcovitch, A.; Kponou, A.; Prelec, K.; Alessi, J.

1995-01-01

Bookhaven, an Electron Beam Ion Source (EBIS) is now operational. This source is being used as a test bed to answer questions relevant to the eventual design of an EBIS-based heavy ion injector for RHIC. Such a source can easily produce ions such as Au 43+ but the challenge lies in reaching intensities of interest for RHIC (3 x 10 9 particles/pulse). The source studies are planned to address issues such as scaling of the electron beam to 10 A, possible onset (and control) of instabilities, ion injection, and parametric studies of output emittance

The Influence of Heat Treatment and Quencing Media at Bronze 80% Cu–20% Sn toward Fatique Life

Directory of Open Access Journals (Sweden)

Anak Agung Istri Agung Sri Komaladewi

2012-11-01

Full Text Available Production of the Balinese gamelan product rest on molding process which then continued with forging process, adjustment,and finally the finishing process. But still often to make the failure from this material like. The material become brokebecause heavy thing with the user processing (playing gambelan with continuity in the long time. The broke that happenfrom the heavy thing by the continuety that is called fatigue. At this examination the things that will be up is how much theheat treatment influence and the cooler thing with the fatigue life through the Reversed Bending process. By to variated theheat treatment and cooler thing to Bronze mixture 80%Cu and 20%Sn. This examination to aim at knowing the heattreatment influence and cooler thing at the composition of Bronze 80%Cu and 20%Sn about the fatigue life.The makingprocess of this things made by copper solution and the white Tin with the composition are 80%Cu and 20%Sn by variatedheat treatment and cooler media. The produce of this solution will print with the Reversed Bending speciment. Then thespeciment gift the heat treatment about 6500 C, 7000 C till 7500 C, and then the speciment keep cold by the water, oil and theair. The thing will be analize from the breach counture, Macro Structure and Micro Structure.The examination produceshowing the growing up at the fatigue life in the Bronze mixture 80%Cu - 20%Sn, From the heat treatment 6500 C, 7000 Cand 7500 C and become the drop age fatigue with the water cooler media with the age fatigue abaut 36621 cycle, and thefatigue by oil about 44975 cycle and the air cooler age fatigue about 55191 cycle. The inspection makro structure thebreach face colouring litle bit dark and the inspection mikro structure, the metal structure lool more bright.

High density matter at RHIC

Indian Academy of Sciences (India)

QCD predicts a phase transition between hadronic matter and a quark-gluon plasma at high energy density. The relativistic heavy ion collider (RHIC) at Brookhaven National Laboratory is a new facility dedicated to the experimental study of matter under extreme conditions. Already the first round of experimental results at ...

SCHOTTKY MEASUREMENTS DURING RHIC 2000

International Nuclear Information System (INIS)

CAMERON, P.; CUPOLO, J.; DEGEN, C.; HAMMONS, L.; KESSELMAN, M.; LEE, R.; MEYER, A.; SIKORA, R.

2001-01-01

The 2GHz Schottky system was a powerful diagnostic during RHIC 2000 commissioning. A continuous monitor without beam excitation, it provided betatron tune, chromaticity, momentum spread relative emittance, and synchrotron tune. It was particularly useful during transition studies. In addition, a BPM was resonated at 230MHz for Schottky measurements

Review of RHIC [Relativistic Heavy Ion Collider] as a B factory

International Nuclear Information System (INIS)

Morse, W.M.

1988-01-01

A dedicated B physics experiment which was considered at the 1988 RHIC Summer Workshop was discussed. The machine may operate in a p-p mode with a luminosity in excess of 10 32 cm/sup /minus/2/ sec/sup /minus/1/ at 250 /times/ 250 GeV. The most ambitious physics objective of such an experiment would be the study of CP nonconservation. Particular emphasis at the workshop was given to the self tagging mode B → K + ο/sup minus/. Experimental techniques developed during this experiment would be extremely useful for more ambitious projects anticipated at the SSC. 4 figs

Pulse tube coolers for Meteosat third generation

International Nuclear Information System (INIS)

Butterworth, James; Aigouy, Gérald; Chassaing, Clement; Debray, Benoît; Huguet, Alexandre

2014-01-01

Air Liquide's Large Pulse Tube Coolers (LPTC) will be used to cool the focal planes of the Infrared Sounder (IRS) and Flexible Combined Imager (FCI) instruments aboard the ESA/Eumetsat satellites Meteosat Third Generation (MTG). This cooler consists of an opposed piston linear compressor driving a pulse tube cold head and the associated drive electronics including temperature regulation and vibration cancellation algorithms. Preparations for flight qualification of the cooler are now underway. In this paper we present results of the optimization and qualification activities as well as an update on endurance testing

MEASURING LOCAL GRADIENT AND SKEW QUADRUPOLE ERRORS IN RHIC IRS

International Nuclear Information System (INIS)

CARDONA, J.; PEGGS, S.; PILAT, R.; PTITSYN, V.

2004-01-01

The measurement of local linear errors at RHIC interaction regions using an ''action and phase'' analysis of difference orbits has already been presented [2]. This paper evaluates the accuracy of this technique using difference orbits that were taken when known gradient errors and skew quadrupole errors were intentionally introduced. It also presents action and phase analysis of simulated orbits when controlled errors are intentionally placed in a RHIC simulation model

Phonon Anharmonicity of Germanium in the Temperature Range 80-880 K

Energy Technology Data Exchange (ETDEWEB)

Nelin, G; Nilsson, G

1974-06-15

Phonon frequency shifts and line widths in germanium have been studied in the temperature range 80 - 880 K by means of thermal neutron spectrometry. The results cannot be described in terms of the quasiharmonic approximation in which phonon frequencies are solely volume dependent. Theoretical calculations are found to be more satisfactory for the Raman frequency than for most other modes. A good account of the observed shifts is given by a proposal due to Barron according to which the relative frequency renormalization of a crystal is proportional to the total harmonic vibrational energy. An analysis of the gradients of measured dispersion relations in the principal symmetry directions at 80 K is presented. It is shown that accidental degeneracies may influence the dispersion

Helical spin rotators and snakes for RHIC

International Nuclear Information System (INIS)

Ptitsin, V.I.; Shatunov, Yu.M.; Peggs, S.

1995-01-01

The RHIC collider, now under construction at BNL, will have the possibility of polarized proton-proton collisions up to a beam energy of 250 Gev. Polarized proton beams of such high energy can be only obtained with the use of siberian snakes, a special kind of spin rotator that rotates the particle spin by 180 degree around an axis lying in the horizontal plane. Siberian snakes help to preserve the beam polarization while numerous spin depolarizing resonances are crossed, during acceleration. In order to collide longitudinally polarized beams, it is also planned to install spin rotators around two interaction regions. This paper discusses snake and spin rotator designs based on sequences of four helical magnets. The schemes that were chosen to be applied at RHIC are presented

Verification of the high temperature phase by the electron pair measurement at RHIC

International Nuclear Information System (INIS)

Akiba, Yasuyuki

2013-01-01

At the high energy nuclear collisions of the RHIC accelerator, the high density parton materials are created. If the matter is the quark gluon plasma (QGP) in the high temperature phase of the QCD, thermal photons are expected to be to be radiated there. The direct photon production from the gold + gold collision reactions at RHIC has been measured by using the 'virtual photon method'. In the gold + gold collisions, very many photons are produced compared with the p + p collisions. The production of the excess direct photons approximately agrees with the theoretical prediction of the thermal photon production from the initial temperature from 300 to 600 MeV QGP. In the present explanatory text, the direct photon measurements at the RHENIX experiments of RHIC are described starting from the discovery of high density matter by RHIC. The photon measurements which give direct evidence of the high temperature state and the virtual photon measurement method are reported briefly. The measurements of the direct photons and the estimation of the initial temperature at RHIC are described in detail with illustrations. Finally, some recent results are added and the ALICE experiments of LHC are referred. (S. Funahashi)

Re-visiting RHIC snakes: OPERA fields, n₀ dance

Energy Technology Data Exchange (ETDEWEB)

Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gupta, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2017-09-22

In this Tech. Note RHIC snakes and stable spin direction $\\vector{n}$₀(s) are re-visited, based on OPERA-computed field maps of the former. The numerical simulations so undertaken provide various outcomes regarding RHIC optics and spin dynamics, in relation with orbital and focusing effects resulting from the use of this realistic 3-D representation of the snakes.

UP-GRADED RHIC INJECTION SYSTEM.

Energy Technology Data Exchange (ETDEWEB)

HAHN,H.FISCHER,W.SEMERTZIDIS,Y.K.WARBURTON,D.S.

2003-05-12

The design of the RHIC injection systems anticipated the possibility of filling and operating the rings with a 120 bunch pattern, corresponding to 110 bunches after allowing for the abort gap. Beam measurements during the 2002 run confirmed the possibility, although at the expense of severe transverse emittance growth and thus not on an operational basis. An improvement program was initiated with the goal of reducing the kicker rise time from 110 to {approx}95 ns and of minimizing pulse timing jitter and drift. The major components of the injection system are 4 kicker magnets and Blmlein pulsers using thyratron switches. The kicker terminating resistor and operating voltage was increased to reduce the rise time. Timing has been stabilized by using commercial trigger units and extremely stable dc supplies for the thyratron reservoir. A fiber optical connection between control room and the thyratron trigger unit has been provided, thereby allowing the operator to adjust timing individually for each kicker unit. The changes were successfully implemented for use in the RHIC operation.

Experimental overview on small colliding systems at RHIC

Energy Technology Data Exchange (ETDEWEB)

Stankus, Paul

2016-12-15

Beginning with the observation of ridge/flow-like features in pair correlations measurements in p+Pb, d+Au and high-density p+p events at RHIC and LHC, the last few years have seen a great surge of interest in the question of whether anything like a hot, locally-equilibrated QCD medium is formed in the small systems at collider energies. Many intriguing and suggestive results have been presented, but conclusions about medium formation must be approached with care. This presentation will attempt to summarize the experimental results from small colliding systems measured at RHIC, as part of a careful and objective evaluation of this question.

Overview of magnetic nonlinear beam dynamics in the RHIC

International Nuclear Information System (INIS)

Luo, Y.; Bai, M.; Beebe-Wang, J.; Bengtsson, J.; Calaga, R.; Fischer, W.; Jain, A.; Pilat, F.; Ptitsyn, V.; Malitsky, N.; Robert-Demolaize, G.; Satogata, T.; Tepikian, S.; Tomas, R.; Trbojevic, D.

2009-01-01

In this article we review our studies of nonlinear beam dynamics due to the nonlinear magnetic field errors in the Relativistic Heavy Ion Collider (RHIC). Nonlinear magnetic field errors, including magnetic field errors in interaction regions (IRs), chromatic sextupoles, and sextupole components from arc main dipoles are discussed. Their effects on beam dynamics and beam dynamic aperture are evaluated. The online methods to measure and correct the IR nonlinear field errors, second order chromaticities, and horizontal third order resonance are presented. The overall strategy for nonlinear corrections in RHIC is discussed

Radiant coolers - Theory, flight histories, design comparisons and future applications

Science.gov (United States)

Donohoe, M. J.; Sherman, A.; Hickman, D. E.

1975-01-01

Radiant coolers have been developed for application to the cooling of infrared detectors aboard NASA earth observation systems and as part of the Defense Meteorological Satellite Program. The prime design constraints for these coolers are the location of the cooler aboard the satellite and the satellite orbit. Flight data from several coolers indicates that, in general, design temperatures are achieved. However, potential problems relative to the contamination of cold surfaces are also revealed by the data. A comparison among the various cooler designs and flight performances indicates design improvements that can minimize the contamination problem in the future.

Production of quarkonia at RHIC

Czech Academy of Sciences Publication Activity Database

Vértési, Robert

2016-01-01

Roč. 31, 28-29 (2016), č. článku 1645036. ISSN 0217-751X R&D Projects: GA ČR GA13-20841S Institutional support: RVO:61389005 Keywords : Brookhaven RHIC Coll * quark onium: heavy * quark onium: production * quark gluon: plasma Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.597, year: 2016

Thermal and flow considerations for the 80 K shield of the SSC magnet cryostats

International Nuclear Information System (INIS)

Abramovich, S.; Yuecel, A.; Demko, J.; Thirumaleshwar, M.

1994-01-01

The nominal temperatures in the SSC magnets range between 4.2 K in the superconducting coils and 300 K on the cryostat outer wall. To minimize the 4 K heat load, one thermal shield cooled by liquid and vapor nitrogen flows at 84 K, and another cooled by helium flow at 20 K are incorporated in the cryostat. Tubes attached to the shields serve as conduits for the cryogens. The liquid nitrogen tube in the cryostat is used for shield refrigeration and also for liquid distribution around the SSC rings. The second nitrogen line is used to return the vapor to the helium refrigerators for helium precooling. The nominal LN2 flow from a 4.3 km long cryogenic string (4 sections) to the surface is 64 g/s. The total liquid nitrogen consumption of approximately 5000 g/s will be supplied at one, two or more locations on the surface. The total heat load of the 80 K shield is estimated as 3.2 W/m: about 50% is composed of infrared radiation; the remaining 50% is by heat conduction through supports, vacuum barriers and other thermal connections between the shield and the 300 K outer wall. The required LN2 flow rate depends on the distribution and circulation schemes. The LN2 temperature will in turn vary depending on the flow rate and on the recooling method used. For example, with a massflow of 400 g/s of LN2 the temperature rises from 82 K to 86 K between two compact recoolers 1 km apart. This temperature is higher than desired. The temperature can be reduced by increasing the flow rate of the liquid or by using the continuous recooling scheme. This paper discusses some thermal problems caused by certain mechanical designs of the 80 K shield and the possible improvement by using continuous recooling. The authors present results of the 80 K shield temperature distribution analysis, the 20 K shield heat load augmentation resulting from the increased 80 K shield temperatures, the continuous nitrogen recooling scheme and some flow timing related analysis

Ferrite HOM Absorber for the RHIC ERL

Energy Technology Data Exchange (ETDEWEB)

Hahn,H.; Choi, E.M.; Hammons, L.

2008-10-01

A superconducting Energy Recovery Linac is under construction at Brookhaven National Laboratory to serve as test bed for RHIC upgrades. The damping of higher-order modes in the superconducting five-cell cavity for the Energy-Recovery linac at RHIC is performed exclusively by two ferrite absorbers. The ferrite properties have been measured in ferrite-loaded pill box cavities resulting in the permeability values given by a first-order Debye model for the tiled absorber structure and an equivalent permeability value for computer simulations with solid ring dampers. Measured and simulated results for the higher-order modes in the prototype copper cavity are discussed. First room-temperature measurements of the finished niobium cavity are presented which confirm the effective damping of higher-order modes in the ERL. by the ferrite absorbers.

Elliptic flow and incomplete equilibration at RHIC

CERN Document Server

Bhalerao, R S; Borghini, N; Ollitrault, Jean Yves

2005-01-01

We argue that RHIC data, in particular those on the anisotropic flow coefficients v_2 and v_4, suggest that the matter produced in the early stages of nucleus-nucleus collisions is incompletely thermalized. We interpret the parameter (1/S)(dN/dy), where S is the transverse area of the collision zone and dN/dy the multiplicity density, as an indicator of the number of collisions per particle at the time when elliptic flow is established, and hence as a measure of the degree of equilibration. This number serves as a control parameter which can be varied experimentally by changing the system size, the centrality or the beam energy. We provide predictions for Cu-Cu collisions at RHIC as well as for Pb-Pb collisions at the LHC.

80 kV electrostatic wire septum for AmPS

International Nuclear Information System (INIS)

Linden, A. van der; Bijleveld, J.H.M.; Rookhuizen, H.B.; Bruinsma, P.J.T.; Heine, E.; Lassing, P.; Prins, E.

1992-01-01

The Amsterdam Pulse Stretcher (AmPS) ring aims at a 100% duty cycle operation by means of slow extraction of injected electron beam pulses of 2.1 μs. In the extraction process of the AmPS, the extracted beam is intercepted from the circulating beam by the 1 m long electrostatic wire septum. For a bending angle of 4.4 mrad the maximum anode voltage is 80 kV. Care has been given to the electric field distribution at the entrance and exit of the septum and to the insulators, required to support the anode. Prototype tests have been successful up to an anode voltage of 120 kV. (R.P.) 9 refs.; 5 figs

Fuel cell cooler-humidifier plate

Science.gov (United States)

Vitale, Nicholas G.; Jones, Daniel O.

2000-01-01

A cooler-humidifier plate for use in a proton exchange membrane (PEM) fuel cell stack assembly is provided. The cooler-humidifier plate combines functions of cooling and humidification within the fuel cell stack assembly, thereby providing a more compact structure, simpler manifolding, and reduced reject heat from the fuel cell. Coolant on the cooler side of the plate removes heat generated within the fuel cell assembly. Heat is also removed by the humidifier side of the plate for use in evaporating the humidification water. On the humidifier side of the plate, evaporating water humidifies reactant gas flowing over a moistened wick. After exiting the humidifier side of the plate, humidified reactant gas provides needed moisture to the proton exchange membranes used in the fuel cell stack assembly. The invention also provides a fuel cell plate that maximizes structural support within the fuel cell by ensuring that the ribs that form the boundaries of channels on one side of the plate have ends at locations that substantially correspond to the locations of ribs on the opposite side of the plate.

Open Heavy Flavor and Quarkonia Results at RHIC

Science.gov (United States)

Nouicer, Rachid

2017-12-01

RHIC experiments carry out a comprehensive physics program which studies open heavy flavor and quarkonium production in relativistic heavy-ion collisions. The discovery at RHIC of large high-pT suppression and flow of electrons from heavy quarks flavors have altered our view of the hot and dense matter formed in central Au + Au collisions at GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. In recent years, the RHIC experiments upgraded the detectors; (1) PHENIX Collaboration installed silicon vertex tracker (VTX) at mid-rapidity region and forward silicon vertex tracker (FVTX) at the forward rapidity region, and (2) STAR Collaboration installed the heavy flavor tracker (HFT) and the muon telescope detector (MTD) both at the mid-rapidity region. With these new upgrades, both experiments have collected large data samples. These new detectors enhance the capability of heavy flavor measurements via precision tracking. The PHENIX experiments established measurements of ψ(1S) and ψ(2S) production as a function of system size, p + p, p + Al, p + Au, and 3He + Au collisions at GeV. In p/3He + A collisions at forward rapidity, we observe no difference in the ψ(2S)/ψ(1S) ratio relative to p + p collisions. At backward rapidity, where the comoving particle density is higher, we find that the ψ(2S) is preferentially suppressed by a factor of two. STAR Collaboration presents the first J/ψ and ϒ measurements in the di-muon decay channel in Au + Au collisions at GeV at mid-rapidity at RHIC. We observe clear J/ψ RAA suppression and qualitatively well described by transport models simultaneously accounting for dissociation and regeneration processes.

Open Heavy Flavor and Quarkonia Results at RHIC

Directory of Open Access Journals (Sweden)

Nouicer Rachid

2017-01-01

Full Text Available RHIC experiments carry out a comprehensive physics program which studies open heavy flavor and quarkonium production in relativistic heavy-ion collisions. The discovery at RHIC of large high-pT suppression and flow of electrons from heavy quarks flavors have altered our view of the hot and dense matter formed in central Au + Au collisions at SNN=200 GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. In recent years, the RHIC experiments upgraded the detectors; (1 PHENIX Collaboration installed silicon vertex tracker (VTX at mid-rapidity region and forward silicon vertex tracker (FVTX at the forward rapidity region, and (2 STAR Collaboration installed the heavy flavor tracker (HFT and the muon telescope detector (MTD both at the mid-rapidity region. With these new upgrades, both experiments have collected large data samples. These new detectors enhance the capability of heavy flavor measurements via precision tracking. The PHENIX experiments established measurements of ψ(1S and ψ(2S production as a function of system size, p + p, p + Al, p + Au, and 3He + Au collisions at SNN=200 GeV. In p/3He + A collisions at forward rapidity, we observe no difference in the ψ(2S/ψ(1S ratio relative to p + p collisions. At backward rapidity, where the comoving particle density is higher, we find that the ψ(2S is preferentially suppressed by a factor of two. STAR Collaboration presents the first J/ψ and ϒ measurements in the di-muon decay channel in Au + Au collisions at SNN=200 GeV at mid-rapidity at RHIC. We observe clear J/ψ RAA suppression and qualitatively well described by transport models simultaneously accounting for dissociation and regeneration processes.

Relativistic nucleus-nucleus collisions: from the BEVALAC to RHIC

International Nuclear Information System (INIS)

Stock, Reinhard

2004-01-01

I briefly describe the initial goals of relativistic nuclear collision research, focusing on the LBL Bevatron/Bevalac facility in the 1970s. An early concept of high hadronic density fireball formation, and subsequent isentropic decay (preserving information of the high-density stage), led to an outline of physics observables that could determine the nuclear matter equation of state at several times the nuclear ground state matter density. With the advent of QCD the goal of locating and characterizing the hadron-parton deconfinement phase transformation suggested the need for higher √s, the research thus shifting to the BNL AGS and CERN SPS, and finally to RHIC at BNL. A set of physics observables is discussed where present data span the entire √s domain, from Bevalac and SIS at GSI, to high RHIC energy. Referring, selectively, to data concerning bulk hadron production, the overall √s evolution of directed and radial flow observables, and of pion pair Bose-Einstein correlation is discussed. The hadronization process is studied in the grand canonical statistical model. The resulting hadronization points in the plane T versus μ B converge onto the parton-hadron phase boundary predicted by finite μ B lattice QCD, from high SPS to RHIC energy. At lower SPS and high AGS energy a steep strangeness maximum occurs at which the Wroblewski parameter λ s ∼ 0.6; a possible connection to the QCD critical point is discussed. Finally the unique new RHIC physics is addressed: high-p T hadron suppression and jet 'tomography'

Electromagnetic radiation from nuclear collisions at RHIC energies

CERN Document Server

Turbide, Simon; Frodermann, Evan; Heinz, Ulrich

2008-01-01

The hot and dense strongly interacting matter created in collisions of heavy nuclei at RHIC energies is modeled with relativistic hydrodynamics, and the spectra of real and virtual photons produced at mid-rapidity in these events are calculated. Several different sources are considered, and their relative importance is compared. Specifically, we include jet fragmentation, jet-plasma interactions, the emission of radiation from the thermal medium and from primordial hard collisions. Our calculations consistently take into account jet energy loss, as evaluated in the AMY formalism. We obtain results for the spectra, the nuclear modification factor (R_AA), and the azimuthal anisotropy (v_2) that agree with the photon measurements performed by the PHENIX collaboration at RHIC.

Chromatic analysis and possible local chromatic correction in RHIC

International Nuclear Information System (INIS)

Luo, Y.; Fischer, W.; Gu, X.; Trbojevic, D.

2011-01-01

In this article we will answer the following questions for the RHIC polarized proton (p-p) and Au-Au run lattices: (1) what are the sources of second order chromaticities? (2) what is the dependence of second order chromaticity on the on-momentum β-beat? (3) what is the dependence of second order chromaticity on β* at IP6 and IP8? To answer these questions, we use the perturbation theory to numerically calculate the contributions of each quadrupole and sextupole to the first, second, and third order chromaticities. Possible local methods to reduce chromatic effects in RHIC ring are shortly discussed.

Silicon drift-chamber studies for possible use at RHIC

International Nuclear Information System (INIS)

Humanic, T.J.

1990-01-01

It is proposed to continue the program now underway at the University of Pittsburgh to study the feasibility of using silicon drift-chambers as particle tracking devices at RHIC. We are currently testing a UA6-type detector obtained from BNL and plan to also study a new device that will become available this year: a cylindrical geometry detector designed for NA45 (CERN). In addition we propose to fabricate and study a detector to be used in vertex determination for the RHIC OASIS experiment. The two-year budget for this proposal is $246.962. 5 refs., 12 figs

Experimental investigation of a super performance dew point air cooler

International Nuclear Information System (INIS)

Xu, Peng; Ma, Xiaoli; Zhao, Xudong; Fancey, Kevin

2017-01-01

Highlights: •The cooler had a complex heat & mass exchanger with an advanced wet material layer. •Intermittent water supply scheme was implemented. •The cooler achieved 100–160% higher COP compared to the existing dew point coolers. •Electricity use of the cooler was reduced by 50–70% compared to existing dew coolers. •This optimal working air ratio was 0.364 that enabled maximised cooling effectiveness. -- Abstract: This paper presents an experimental investigation of a super performance dew point air cooler which, by employing a super performance wet material layer, innovative heat and mass exchanger and intermittent water supply scheme, has achieved a significantly higher energy efficiency (i.e. Coefficient of Performance, COP) and a much lower electrical energy use compared to the existing air coolers of the same type. This involves the dedicated system design & construction, fully planned experimental testing under various simulated climatic conditions representing the climate of hot & dry, warm & dry, moderate, warm & humid and standard lab testing condition, testing results analysis and discussion, as well as the parallel comparison against the commercial dew point air cooler. Under the standard test condition, i.e. dry bulb temperature of 37.8 °C and coincident wet bulb temperature of 21.1 °C, the prototype cooler achieved the wet-bulb cooling effectiveness of 114% and dew-point cooling effectiveness of 75%, yielding a significantly high COP value of 52.5 at the optimal working air ratio of 0.364. The testing also indicated that the lower inlet air relative humidity led to a higher cooling efficiency, while the lower cooling output helped increase COP and cooling effectiveness (including the wet-bulb effectiveness and dew-point effectiveness) of the cooler.

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER, VOLUME 37, RHIC SPIN COLLABORATION MEETING VI (PART 2)

International Nuclear Information System (INIS)

Bland, L.; Saito, N.

2001-01-01

The second part of the sixth RHIC Spin Collaboration (RSC) meeting was held on November 15, 2001 at Brookhaven National Laboratory. Previous meetings have elaborated on the new generation of proton spin-structure studies (e.g. gluon polarization and flavor separation of q and bar q polarizations via real W ± production) enabled by studying polarized proton collisions at energies and momentum transfers where perturbative QCD models are expected to be applicable. The focus of this meeting was on many of the experimental issues that must be resolved to achieve these physics goals. This summary is written with the benefit of hindsight following the completion of the first-ever run of a polarized proton collider. This first run can be considered as a successfully completed milestone of the RHIC Spin Collaboration. Other milestones remain important. Long term machine items were identified in Waldo Mackay's talk, the most important being the completion of the spin rotator magnets that will be installed in 2002 to allow the flexible orientation of the proton beam polarization at the PHENM and STAR experiments. At the meeting Waldo discussed a stronger partial snake magnet for the AGS as a means of producing highly polarized proton beams to inject into RHIC. Developments subsequent to this meeting suggest that a superconducting helical dipole magnet may be feasible for the AGS, and is likely to be needed to achieve the 70% beam polarization in RHIC. Longer term items were also presented, including potential increases in luminosity by the addition of electron cooling to RHIC and the possibility of increasing the collision energy by ∼20% by replacement of the DX magnets. These items could be considered for a second generation of RHIC spin experiments. The other topics covered at the meeting were related to polarimetry and to the absolute calibration of the proton beam polarization in RHIC. These topics were divided into short- and long-term solutions to polarimetry issues

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER, VOLUME 37, RHIC SPIN COLLABORATION MEETING VI (PART 2).

Energy Technology Data Exchange (ETDEWEB)

BLAND, L.; SAITO, N.

2001-11-15

The second part of the sixth RHIC Spin Collaboration (RSC) meeting was held on November 15, 2001 at Brookhaven National Laboratory. Previous meetings have elaborated on the new generation of proton spin-structure studies (e.g. gluon polarization and flavor separation of q and {bar q} polarizations via real W{sup {+-}} production) enabled by studying polarized proton collisions at energies and momentum transfers where perturbative QCD models are expected to be applicable. The focus of this meeting was on many of the experimental issues that must be resolved to achieve these physics goals. This summary is written with the benefit of hindsight following the completion of the first-ever run of a polarized proton collider. This first run can be considered as a successfully completed milestone of the RHIC Spin Collaboration. Other milestones remain important. Long term machine items were identified in Waldo Mackay's talk, the most important being the completion of the spin rotator magnets that will be installed in 2002 to allow the flexible orientation of the proton beam polarization at the PHENM and STAR experiments. At the meeting Waldo discussed a stronger partial snake magnet for the AGS as a means of producing highly polarized proton beams to inject into RHIC. Developments subsequent to this meeting suggest that a superconducting helical dipole magnet may be feasible for the AGS, and is likely to be needed to achieve the 70% beam polarization in RHIC. Longer term items were also presented, including potential increases in luminosity by the addition of electron cooling to RHIC and the possibility of increasing the collision energy by {approx}20% by replacement of the DX magnets. These items could be considered for a second generation of RHIC spin experiments. The other topics covered at the meeting were related to polarimetry and to the absolute calibration of the proton beam polarization in RHIC. These topics were divided into short- and long-term solutions to

Power systems for the RHIC first sextant test

International Nuclear Information System (INIS)

Schultheiss, C.; Bruno, D.; Feng, P.K.

1997-01-01

The first sextant test of the RHIC project is an opportunity to evaluate the many systems that must work together for the accelerator to operate. For the main dipole string, the actual main quadrupole power supply with its DSP regulator and output circuit compartment will be used. Temporary supplies will be used for the main quadrupole string, quadrupole offset, and quadrupole shunt supplies. This will let the authors both measure the performance of the main supply as well as determine the interaction among other power elements in the circuit. Correction elements will also be powered. The actual gamma-T power supplies will be used, as well as temporary supplies for the dipole correctors and sextupole supplies. Some of these units are required for beam to be transported, others are to be operated without beam to measure their performance, and how they interact with their superconducting loads. The power supply equipment, and that of other systems, required an infrastucture of AC power and output cable distribution in the RHIC tunnel, outlying service buildings, and interconnecting the tunnel to the service buildings. This note will describe the performance of the RHIC power supply systems during the sextant test, and the experience gained from this exercise

Micro-cooler enhancements by barrier interface analysis

International Nuclear Information System (INIS)

Stephen, A.; Dunn, G. M.; Glover, J.; Oxley, C. H.; Bajo, M. Montes; Kuball, M.; Cumming, D. R. S.; Khalid, A.

2014-01-01

A novel gallium arsenide (GaAs) based micro-cooler design, previously analysed both experimentally and by an analytical Heat Transfer (HT) model, has been simulated using a self-consistent Ensemble Monte Carlo (EMC) model for a more in depth analysis of the thermionic cooling in the device. The best fit to the experimental data was found and was used in conjunction with the HT model to estimate the cooler-contact resistance. The cooling results from EMC indicated that the cooling power of the device is highly dependent on the charge distribution across the leading interface. Alteration of this charge distribution via interface extensions on the nanometre scale has shown to produce significant changes in cooler performance

Quench observation using quench antennas on RHIC IR quadrupole magnets

International Nuclear Information System (INIS)

Ogitsu, T.; Terashima, A.; Tsuchiya, K.; Ganetis, G.; Muratore, J.; Wanderer, P.

1995-01-01

Quench observation using quench antennas is now being performed routinely on RHIC dipole and quadrupole magnets. Recently, a quench antenna was used on a RHIC IR magnet which is heavily instrumented with voltage taps. It was confirmed that the signals detected in the antenna coils do not contradict the voltage tap signals. The antenna also detects a sign of mechanical disturbance which could be related to a training quench. This paper summarizes signals detected in the antenna and discusses possible causes of these signals

Quench observation using quench antennas on RHIC IR quadrupole magnets

International Nuclear Information System (INIS)

Ogitsu, T.; Terashima, A.; Tsuchiya, K.; Ganetis, G.; Muratore, J.; Wanderer, P.

1996-01-01

Quench observation using quench antennas is now being performed routinely on RHIC dipole and quadrupole magnets. Recently, a quench antenna was used on a RHIC IR magnet which is heavily instrumented with voltage taps. It was confirmed that the signals detected in the antenna coils do not contradict the voltage tap signals. The antenna also detects a sign of mechanical disturbance which could be related to a training quench. This paper summarizes signals detected in the antenna and discusses possible causes of these signals

Simulations of silicon vertex tracker for star experiment at RHIC

Energy Technology Data Exchange (ETDEWEB)

Odyniec, G.; Cebra, D.; Christie, W.; Naudet, C.; Schroeder, L.; Wilson, W. [Lawrence Berkeley Lab., CA (United States); Liko, D. [Institut fur Hochenenergiephysik, Vienna, (Austria); Cramer, J.; Prindle, D.; Trainor, T. [Univ. of Washington, Seattle (United States); Braithwaite, W. [Univ. of Arkansas, Little Rock (United States)

1991-12-31

The first computer simulations to optimize the Silicon Vertex Tracker (SVT) designed for the STAR experiment at RHIC are presented. The physics goals and the expected complexity of the events at RHIC dictate the design of a tracking system for the STAR experiment. The proposed tracking system will consist of a silicon vertex tracker (SVT) to locate the primary interaction and secondary decay vertices and to improve the momentum resolution, and a time projection chamber (TPC), positioned inside a solenoidal magnet, for continuous tracking.

Strangeness by Thermal Model Simulation at RHIC

Institute of Scientific and Technical Information of China (English)

SHI Xing-Hua; MA Yu-Gang; CAI Xiang-Zhou; CHEN Jin-Hui; MA Guo-Liang; ZHONG Chen

2009-01-01

The local temperature effect on strangeness enhancement in relativistic heavy ion collisions is discussed in the framework of the thermal model in which the K+ /h+ ratio becomes smaller with increasing freeze-out temperature.Considering that most strangeness particles of final-state particles are from the kaon meson,the temperature effect may play a role in strangeness production in hot dense matter where a slightly different temperature distribution in different areas could be produced by jet energy loss.This phenomenon is predicted by thermal model calculation at RHIC energy.The Ε-/φ ratio in central Au+Au collisions at 200 GeV from the thermal model depends on the freeze-out temperature obviously when γs is different.It should be one of the reasons why strangeness enhancements of Ε and φ are different though they include two strange quarks.These results indicate that thermodynamics is an important factor for strangeness production and the strangeness enhancement phenomenon.

Intra-beam Scattering Theory and RHIC Experiments

International Nuclear Information System (INIS)

Wei, J.; Fedotov, A.; Fischer, W.; Malitsky, N.; Parzen, G.; Qiang, J.

2005-01-01

Intra-beam scattering is the leading mechanism limiting the luminosity in heavy-ion storage rings like the Relativistic Heavy Ion Collider (RHIC). The multiple Coulomb scattering among the charged particles causes transverse emittance growth and longitudinal beam de-bunching and beam loss, compromising machine performance during collision. Theoretically, the original theories developed by Piwinski, Bjorken, and Mtingwa only describe the rms beam size growth of an unbounded Gaussian distribution. Equations based on the Fokker-Planck approach are developed to further describe the beam density profile evolution and beam loss. During the 2004 RHIC heavy-ion operation, dedicated IBS experiments were performed to bench-mark the rms beam size growth, beam loss, and profile evolution both for a Gaussian-like and a longitudinal hollow beam. This paper summarizes the IBS theory and discusses the experimental bench-marking results

The resistivity of Y1Ba2Cu3O7 between 80 K and 1240 K

International Nuclear Information System (INIS)

Fisher, B.; Polturak, E.; Koren, G.; Kessel, A.; Fischer, R.; Harel, L.

1987-01-01

Resistivity measurements between 80-1240 K and dilatometric measurements between 300-1200 K in YBa 2 Cu 3 O 7 are reported. We found that the resistivity increases exponentially with temperature, with different exponents below and above the tetragonal-orthorhombic transition. The thermal expansion coefficient also changes at this transition. We suggest that conduction occurs by tunneling of electrons through potential barriers in the lattice, the width of which increases with temperature. (author)

GLOBAL AND LOCAL COUPLING COMPENSATION EXPERIMENTS IN RHIC USING AC DIPOLES

International Nuclear Information System (INIS)

CALAGA, R.; FRANCHI, A., TOMAS, R.; CERN)

2006-01-01

Compensation of transverse coupling during the RHIC energy ramp has been proven to be non-trivial and tedious. The lack of accurate knowledge of the coupling sources has initiated several efforts to develop fast techniques using turn-by-turn BPM data to identify and compensate these sources. This paper aims to summarize the beam experiments performed to measure the coupling, matrix and resonance driving terms with the aid of RHIC ac dipoles at injection energy

The low fault HTSL-SQUID cooling system. Final report; Stoerarmes HTSL-SQUID-Kuehlsystem. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Binneberg, A.; Spoerl, G.; Buschmann, H.

1997-03-01

In the context of the research project, work was done for HTSL-SQUID on (1) the development of a thermo-siphon cooler (low fault and continuously working) and (2) the development of a latent storage cooler (low fault and discontinuously working). Two development versions of the latent storage cooler were followed up, the development of a spherical latent storage cooler and the development of an annular vessel latent storage cooler. A further precondition for the construction of the cooler was the use of split Stirling refrigerators as units producing the cold. The experimental sample was built up with refrigerators which could produce a nominal cooling output of 1.2 W at 80 K. Two samples of the thermo-siphon cooler were built, tested and improved. The second sample was developed further as a demonstration model, introduced at meetings and prepared for testing the cooling of HTSL-SQUIDs. The thermo-siphon cooler can be designed for cooling output up to about 2 W at 80 K and can be used controlled for a temperature range of 90 K to 66 K. (orig./MM) [Deutsch] Im Rahmen des Forschungsvorhabens wurde fuer HTSL-SQUID`s an der (1) Entwicklung eines Thermosiphon-Kuehlers (stoerarm und kontinuierlich arbeitend) und (2) Entwicklung eines Latentspeicher-Kuehlers (stoerfrei und diskontinuierlich arbeitend) gearbeitet. Bei dem Latentspeicher-Kuehler wurden zwei Entwicklungsversionen verfolgt, und zwar Entwicklung eines Kugel-Latentspeicher-Kuehlers und Entwicklung eines Ringgefaess-Latentspeicher-Kuehlers. Eine weitere Praemisse zum Aufbau der Kuehler war der Einsatz von Split-Stirling-Kaeltemaschinen als kaelteerzeugende Baugruppe. Die Versuchsmuster wurden mit Kaeltemaschinen aufgebaut, die eine Nennkuehlleistung von 1,2 W bei 80 K erzeugen konnten. Der Thermosiphon-Kuehler wurde in zwei Musterexemplaren aufgebaut, erprobt und verbessert. Das Zweitmuster wurde als Demonstrator weiterentwickelt, zu Fachtagungen vorgestellt und zur Testung der Kuehlung von HTSL

Transverse energy production at RHIC

International Nuclear Information System (INIS)

Sahoo, Raghunath

2006-01-01

The quest for understanding of the possible formation and existence of the quark-gluon plasma (Qp), the deconfined phase of quarks and gluons, has been a major area of research in high energy nuclear physics. High energy nuclear collisions at the Relativistic Heavy Ion Collider (RHIC) has opened a new domain for the exploration of strongly interacting matter at very high energy density and temperature

The methane absorption spectrum near 1.73 μm (5695-5850 cm-1): Empirical line lists at 80 K and 296 K and rovibrational assignments

Science.gov (United States)

Ghysels, M.; Mondelain, D.; Kassi, S.; Nikitin, A. V.; Rey, M.; Campargue, A.

2018-07-01

The methane absorption spectrum is studied at 297 K and 80 K in the center of the Tetradecad between 5695 and 5850 cm-1. The spectra are recorded by differential absorption spectroscopy (DAS) with a noise equivalent absorption of about αmin≈ 1.5 × 10-7 cm-1. Two empirical line lists are constructed including about 4000 and 2300 lines at 297 K and 80 K, respectively. Lines due to 13CH4 present in natural abundance were identified by comparison with a spectrum of pure 13CH4 recorded in the same temperature conditions. About 1700 empirical values of the lower state energy level, Eemp, were derived from the ratios of the line intensities at 80 K and 296 K. They provide accurate temperature dependence for most of the absorption in the region (93% and 82% at 80 K and 296 K, respectively). The quality of the derived empirical values is illustrated by the clear propensity of the corresponding lower state rotational quantum number, Jemp, to be close to integer values. Using an effective Hamiltonian model derived from a previously published ab initio potential energy surface, about 2060 lines are rovibrationnally assigned, adding about 1660 new assignments to those provided in the HITRAN database for 12CH4 in the region.

Nuclear Effects on Heavy Boson Production at RHIC and LHC

CERN Document Server

Zhang, X; Zhang, Xiaofei; Fai, George

2002-01-01

We predict W and Z transverse momentum distributions from proton-proton and nuclear collisions at RHIC and LHC. A resummation formalism with power corrections to the renormalization group equations is used. The dependence of the resummed QCD results on the non-perturbative input is very weak for the systems considered. Shadowing effects are discussed and found to be unimportant at RHIC, but important for LHC. We study the enhancement of power corrections due to multiple scattering in nuclear collisions and numerically illustrate the weak effects of the dependence on the nuclear mass.

Cold matter effects and quarkonium production at RHIC and LHC

Energy Technology Data Exchange (ETDEWEB)

Dos Santos, G. S.; Mariotto, C. B. [Instituto de Matematica, Estatistica e Fisica, Universidade Federal do Rio Grande, Caixa Postal 474, CEP 96203-900, Rio Grande, RS (Brazil); Goncalves, V. P. [Instituto de Fisica e Matematica, Universidade Federal de Pelotas, Caixa Postal 354, CEP 96010-090, Pelotas, RS (Brazil)

2013-03-25

In this work we investigate two cold matter effects in J/{Psi} and {Upsilon} production in nuclear collisions at RHIC and LHC, namely the shadowing effect and nuclear absorption. We characterize these effects by estimating the rapidity dependence of some nuclear ratios in pA and AA collisions at RHIC and LHC, R{sub pA} = d{sigma}{sub pA}(J/{Psi},{Upsilon})/Ad{sigma}{sub pp}(J/{Psi},{Upsilon}) and R{sub AA} = d{sigma}{sub AA}(J/{Psi},{Upsilon})/A{sup 2}d{sigma}{sub pp}(J/{Psi},{Upsilon}).

Variable-speed air-forced cooler technology

OpenAIRE

Siffring, Wolfgang

2016-01-01

Advanced air coolers are able to cool transformer oil more efficiently than older systems. Replacement or expansion of cooling plants by a new solution can lead to reduction of oil temperatures by several degrees and have a positive influence on the service lifetimes of oil and therefore transformers. Or, conversely, better coolers can – at the same oil temperatures – enhance the maximum performance of a transformer or allow it to operate at a higher average load. The upgrade or expansion of ...

The characterization and selection of superconductor wire and cable for RHIC

International Nuclear Information System (INIS)

Greene, A.F.; Garber, M.; Ghosh, A.K.; McChesney, D.; Morgillo, A.

1992-01-01

This report describes the procedures used to select a single vendor for superconductor cable for the RHIC 80 mm dipole and quadrupole magnets, and some insertion dipoles with 110 mm aperture. Experience gained at BNL through involvement with the HERA and SSC Projects provided valuable Teaming experiences for this work. A performance specification was prepared and three qualified vendors were selected to complete a preproduction lot of 63,000 ft. of cable (approximately five multifilament billets). Samples were sent to BNL from every wire spool and from every continuous cable length. Mechanical, electrical and magnetization measurements were made to characterize the material. A data base was used to collect information, to compare BNL and vendor measurements and to study uniformity. Results are presented without specific identification of the vendors involved

Azimuthal anisotropy at RHIC: The first and fourth harmonics

International Nuclear Information System (INIS)

Adams, J.; Adler, C.; Aggarwal, M.M.; Ahammed, Z.; Amonett, J.; Anderson, B.D.; Anderson, M.; Arkhipkin, D.; Averichev, G.S.; Badyal, S.K.; Balewski, J.; Barannikova, O.; Barnby, L.S.; Baudot, J.; Bekele, S.; Belaga, V.V.; Bellwied, R.; Berger, J.; Bezverkhny, B.I.; Bhardwaj, S.; Bhaskar, P.; Bhati, A.K.; Bichsel, H.; Billmeier, A.; Bland, L.C.; Blyth, C.O.; Bonner, B.E.; Botje, M.; Boucham, A.; Brandin, A.; Bravar, A.; Cadman, R.V.; Cai, X.Z.; Caines, H.; Calderon de la Barca Sanchez, M.; Carroll, J.; Castillo, J.; Castro, M.; Cebra, D.; Chaloupka, P.; Chattopadhyay, S.; Chen, H.F.; Chen, Y.; Chernenko, S.P.; Cherney, M.; Chikanian, A.; Choi, B.; Christie, W.; Coffin, J.P.; Cormier, T.M.; Cramer, J.G.; Crawford, H.J.; Das, D.; Das, S.; Derevschikov, A.A.; Didenko, L.; Dietel, T.; Dong, W.J.; Dong, X.; Draper, J.E.; Du, F.; Dubey, A.K.; Dunin, V.B.; Dunlop, J.C.; Dutta Majumdar, M.R.; Eckardt, V.; Efimov, L.G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Faine, V.; Faivre, J.; Fatemi, R.; Filimonov, K.; Filip, P.; Finch, E.; Fisyak, Y.; Flierl, D.; Foley, K.J.; Fu, J.; Gagliardi, C.A.; Gagunashvili, N.; Gans, J.; Ganti, M.S.; Gaudichet, L.; Germain, M.; Geurts, F.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, J.E.; Grachov, O.; Grigoriev, V.; Gronstal, S.; Drosnick, D.; Guedon, M.; Guertin, S.M.; Gupta, A.; Gushin, E.; Hallman, T.J.; Hardtke, D.; Harris, J.W.; Heinz, M.; Henry, T.W.; Heppelmann, S.; Herston, T.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffmann, G.W.; Horsley, M.; Huang, H.Z.; Huang, S.L.; Humanic, T.J.; Igo, G.; Ishihara, A.; Jacobs, P.; Jacobs, W.W.; Janik, M.; Jiang, H.; Johnson, I.; Jones, P.G.; Judd, E.G.; Kabana, S.; Kaneta, M.; Kaplan, M.; Keane, D.; Khodyrev, V.Yu.; Kiryluk, J.; Kisiel, A.; Klay, J.; Klein, S.R.; Klyachko, A.; Koetke, D.D.; Kollegger, T.; Kopytine, S.M.; Kotchenda, L.; Kovalenko, A.D.; Kramer, M.; Kravtsov, P.; Krueger, K.; Kuhn, C.; Kulikov, A.I.; Kumar, A.; et al.

2004-01-01

We report the first observations of the first harmonic (directed flow, v 1 ), and the fourth harmonic (v 4 ), in the azimuthal distribution of particles with respect to the reaction plane in Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). Both measurements were done taking advantage of the large elliptic flow (v 2 ) generated at RHIC. From the correlation of v 2 with v 1 it is determined that v 2 is positive, or in-plane. The integrated v 4 is about a factor of 10 smaller than v 2 . For the sixth (v 6 ) and eighth (v 8 ) harmonics upper limits on the magnitudes are reported

High-pT hadron spectra at RHIC: an overview

International Nuclear Information System (INIS)

Klay, Jennifer L

2005-01-01

Recent results on high transverse momentum (p T ) hadron production in p+p, d+Au and Au+Au collisions at the relativistic heavy-ion collider (RHIC) are reviewed. Comparison of the nuclear modification factors, R dAu (p T ) and R AA (p T ), demonstrates that the large suppression in central Au+Au collisions is due to strong final-state effects. Theoretical models which incorporate jet quenching via gluon bremsstrahlung in the dense partonic medium that is expected in central Au+Au collisions at ultra-relativistic energies are shown to reproduce the shape and magnitude of the observed suppression over the range of collision energies so far studied at RHIC

A high performance DAC/DDS daughter module for the RHIC LLRF platform

International Nuclear Information System (INIS)

Hayes, T.; Harvey, M.; Narayan, G.; Severino, F.; Smith, K.S.; Yuan, S.

2011-01-01

The RHIC LLRF upgrade is a flexible, modular system. Output signals are generated by a custom designed XMC card with 4 high speed digital to analog (DAC) converters interfaced to a high performance field programmable gate array (FPGA). This paper discusses the hardware details of the XMC DAC board as well as the implementation of a low noise rf synthesizer with digital IQ modulation. This synthesizer also provides injection phase cogging and frequency hop rebucketing capabilities. A new modular RHIC LLRF system was recently designed and commissioned based on custom designed XMC cards. As part of that effort a high speed, four channel DAC board was designed. The board uses Maxim MAX5891 16 bit DACs with a maximum update rate of 600 Msps. Since this module is intended to be used for many different systems throughout the Collider Accelerator complex, it was designed to be as generic as possible. One major application of this DAC card is to implement digital synthesizers to provide drive signals to the various cavities at RHIC. Since RHIC is a storage ring with stores that typically last many hours, extremely low RF noise is a critical requirement. Synchrotron frequencies at RHIC range from a few hertz to several hundred hertz depending on the species and point in the acceleration cycle so close in phase noise is a major concern. The RHIC LLRF system uses the Update Link, a deterministic, high speed data link that broadcasts the revolution frequency and the synchronous phase angle. The digital synthesizers use this data to generate a properly phased analog drive signal. The synthesizers must also provide smooth phase shifts for cogging and support frequency shift rebucketing. One additional feature implemented in the FPGA is a digital waveform generator (WFG) that generates I and Q data pairs based on a user selected amplitude and phase profile as a function of time.

Improvement In The COP Of Thermoelectric Cooler

Directory of Open Access Journals (Sweden)

Jatin Patel

2015-08-01

Full Text Available This paper described the study for heat transfer through thermoelectric cooler TEC by use of multistage thermoelectric module. To satisfy the heat dissipation of modern electronic element thermal designers have to increase fin area and fan speed to improve its cooling capacity. However the increase of fin area is restricted by the space. Besides the increase of fan speed would induce noise which damages human health. So air cooling by fan is hardly to meet the requirement of modern electronic component. Recently thermoelectric cooler TEC is applied to electronic cooling with the advantages of small size quietness and reliability. A typical thermoelectric cooler consists of p-type and n-type semiconductor pellets connected electrically in series and sandwiched between two ceramic substrates. Whenever direct current passes through the circuit it causes temperature differential between TEC sides. As a result one face of TEC which is called cold side will be cooled while its opposite face which is called hot side is simultaneously heated. The main problem over the use of TEC is the limited COP and its thermal performance. But these can be eliminated by use of multistage thermoelectric cooler.

The effects of betatron phase advances on beam-beam and its compensation in RHIC

Energy Technology Data Exchange (ETDEWEB)

Luo, Y.; Fischer, W.; Gu, X.; Tepikian, S.; Trbojevic, D.

2011-03-28

In this article we perform simulation studies to investigate the effects of betatron phase advances between the beam-beam interaction points on half-integer resonance driving term, second order chromaticty and dynamic aperture in RHIC. The betatron phase advances are adjusted with artificial matrices inserted in the middle of arcs. The lattices for the 2011 RHIC polarized proton (p-p) run and 2010 RHIC Au-Au runs are used in this study. We also scan the betatron phase advances between IP8 and the electron lens for the proposed Blue ring lattice with head-on beam-beam compensation.

PROGRESS IN TUNE, COUPLING, AND CHROMATICITY MEASUREMENT AND FEEDBACK DURING RHIC RUN 7

Energy Technology Data Exchange (ETDEWEB)

CAMERON,P.; DELLAPENNA, A.; HOFF, L.; LUO, Y.; MARUSIC, A.; SCHULTHEISS, C.; TEPIKIAN, S.; ET AL.

2007-06-25

Tune feedback was first implemented in RHIC in 2002, as a specialist activity. The transition of the tune feedback system to full operational status was impeded by dynamic range problems, as well as by overall loop instabilities driven by large coupling. The dynamic range problem was solved by the CERN development of the Direct Diode Detection Analog Front End. Continuous measurement of all projections of the betatron eigenmodes made possible the world's first implementation of coupling feedback during beam acceleration, resolving the problem of overall loop instabilities. Simultaneous tune and coupling feedbacks were utilized as specialist activities for ramp development during the 2006 RHIC run. At the beginning of the 2007 RHIC run there remained two obstacles to making these feedbacks fully operational in RHIC - chromaticity measurement and control, and the presence of strong harmonics of the power line frequency in the betatron spectrum. We report on progress in tune, coupling, and chromaticity measurement and feedback, and discuss the relevance of our results to LHC commissioning.

A techno-economic analysis of cost savings for retrofitting industrial aerial coolers with variable frequency drives

International Nuclear Information System (INIS)

Miller, Patrick; Olateju, Babatunde; Kumar, Amit

2012-01-01

Highlights: ► Techno-economic models were developed to assess the retrofitting of aerial coolers. ► The IRR for retrofitting with VFDs exceeds 10% for motor sizes above 20 hp. ► The IRR reaches a maximum of 220% for a cooler with fifty, 250 hp motors. ► The simple payback becomes less than 1 year for motors larger than 120 hp. ► Ambient temperature and location affects the profitability of VFD investment. - Abstract: A techno-economic model was created in order to develop curves that show the typical annual energy savings, rate of return, and payback for retrofitting aerial coolers with variable frequency drives (VFDs) for up to 50 motors, motor sizes from 4 to 186 kW (5–250 hp), and varying climate conditions. The cost savings due to installing a VFD depends on the reduction in energy used, as well as the reduction in power demand, the capital cost of the VFD, installation cost of the VFD, change in operating cost, and cost of electricity. The geographic locations examined in this report were Fort McMurray, Calgary, Vancouver, and Thunder Bay. This study found that the IRR increases rapidly with motor size, becomes greater than 10% at a motor size of approximately 15 kW, and may be as high as 220% (for the case of fifty, 186 kW motors). The IRR is sensitive to the number of fan motors retrofitted with VFDs, however the sensitivity rapidly declines as the number of motors is increased beyond five. The simple payback period becomes less than 1 year and nearly independent of number of motors and motor size for motors larger than 90 kW. Ambient temperature and geographic location affect the profitability of the investment, although the IRR only changes by approximately 4%.

Thermodynamic analysis and economical evaluation of two 310-80 K pre-cooling stage configurations for helium refrigeration and liquefaction cycle

Science.gov (United States)

Zhu, Z. G.; Zhuang, M.; Jiang, Q. F.; Y Zhang, Q.; Feng, H. S.

2017-12-01

In 310-80 K pre-cooling stage, the temperature of the HP helium stream reduces to about 80 K where nearly 73% of the enthalpy drop from room temperature to 4.5 K occurs. Apart from the most common liquid nitrogen pre-cooling, another 310-80 K pre-cooling configuration with turbine is employed in some helium cryoplants. In this paper, thermodynamic and economical performance of these two kinds of 310-80 K pre-cooling stage configurations has been studied at different operating conditions taking discharge pressure, isentropic efficiency of turbines and liquefaction rate as independent parameters. The exergy efficiency, total UA of heat exchangers and operating cost of two configurations are computed. This work will provide a reference for choosing 310-80 K pre-cooling stage configuration during design.

Monolithic readout circuits for RHIC

Energy Technology Data Exchange (ETDEWEB)

O`Connor, P.; Harder, J. [Brookhaven National Laboratory, Upton, NY (United States)

1991-12-31

Several CMOS ASICs have been developed for a proposed RHIC experiment. This paper discusses why ASIC implementation was chosen for certain functions, circuit specifications and the design techniques used to meet them, and results of simulations and early prototypes. By working closely together from an early stage in the planning process, in-house ASIC designers and detector and data acquisition experimenters can achieve optimal use of this important technology.

Monolithic readout circuits for RHIC

International Nuclear Information System (INIS)

O'Connor, P.; Harder, J.; Sippach, W.

1991-10-01

Several CMOS ASICs have been developed for a proposed RHIC experiment. This paper discusses why ASIC implementation was chosen for certain functions, circuit specifications and the design techniques used to meet them, and results of simulations and early prototypes. By working closely together from an early stage in the planning process, in-house ASIC designers and detector and data acquisition experimenters can achieve optimal use of this important technology

Conversion of St. Marys conventional grate cooler at the Bowmanville plant

Energy Technology Data Exchange (ETDEWEB)

Keefe, B.P. (Fuller Co., Bethlehem, PA (United States))

1993-11-01

Fuller Company has recently retrofitted the largest operating clinker cooler in North America with its CFG (Controlled Flow Grate) system. The cooler conversion was made to the St. Mary's Cement's 5000 mtpd Folax grate cooler at the Bowmanville plant. The project included conversion of the entire first drive section to Fuller's new cooler design featuring its increased flow resistance grate plates, a maintenance-friendly air distribution system, and a new hydraulic drive unit. As a result of the cooler conversion, significant power and fuel savings were made possible for an already efficient and modern cement producing facility. (author)

RHIC control system

Energy Technology Data Exchange (ETDEWEB)

Barton, D.S. E-mail: dsbarton@bnl.gov; Binello, S.; Buxton, W.; Clifford, T.; D' Ottavio, T.; Hartmann, H.; Hoff, L.T.; Katz, R.; Kennell, S.; Kerner, T.; Laster, J.; Lee, R.C.; Marusic, A.; Michnoff, R.; Morris, J.; Oerter, B.R.; Olsen, R.; Piacentino, J.; Skelly, J.F

2003-03-01

The RHIC control system architecture is hierarchical and consists of two physical layers with a fiber-optic network connection. The Front-End Level systems consist of VME chassis with processors running a real-time operating system and both VME I/O modules and remote bus interfaces. Accelerator device software interfaces are implemented as objects in C++. The network implementation uses high speed, switched Ethernet technology. Specialized hardware modules were built for waveform control of power supplies, multiplexed signal acquisition, and timing services. The Console Level systems are Unix workstations. A strong emphasis has been given to developing highly reusable, standard software tools for use in building physics and diagnostic application software.

RHIC control system

International Nuclear Information System (INIS)

Barton, D.S.; Binello, S.; Buxton, W.; Clifford, T.; D'Ottavio, T.; Hartmann, H.; Hoff, L.T.; Katz, R.; Kennell, S.; Kerner, T.; Laster, J.; Lee, R.C.; Marusic, A.; Michnoff, R.; Morris, J.; Oerter, B.R.; Olsen, R.; Piacentino, J.; Skelly, J.F.

2003-01-01

The RHIC control system architecture is hierarchical and consists of two physical layers with a fiber-optic network connection. The Front-End Level systems consist of VME chassis with processors running a real-time operating system and both VME I/O modules and remote bus interfaces. Accelerator device software interfaces are implemented as objects in C++. The network implementation uses high speed, switched Ethernet technology. Specialized hardware modules were built for waveform control of power supplies, multiplexed signal acquisition, and timing services. The Console Level systems are Unix workstations. A strong emphasis has been given to developing highly reusable, standard software tools for use in building physics and diagnostic application software

Heavy ion physics at BNL, the AGS and RHIC

International Nuclear Information System (INIS)

Lowenstein, D.I.

1985-01-01

The advent of heavy ion acceleration with the AGS at Brookhaven National Laboratory in 1986 and the proposed Relativistic Heavy Ion Collider (RHIC) for 1990 brings us into a temperature and density regime well above anything yet produced and into a time domain of the early universe of 10 -13 -10 -6 seconds. The physics of high energy heavy ions range from the more traditional nuclear physics to the formation of new forms of matter. Quantum Chromodynamics (QCD) is the latest, and as of yet, the most successful theory to describe the interaction of quarks and gluons. The nature of the confinement of the quarks and gluons under extremes of temperature and density is one of the compelling reasons for this new physics program at BNL. There are reasons to believe that with collisions of heavy nuclei at energies in the 10 to 100 GeV/amu range a very large volume of approx. 10 fm 3 would be heated to 200-300 MeV and/or acquire a sufficient quark density (5-10 times normal baryon density) so that the entire contents of the volume would be deconfined and the quarks and gluons would form a plasma. The kinematic region for the extant machines and the proposed RHIC are shown. At AGS energies the baryons in colliding nuclei bring each other to rest, yielding fragmentation regions of high baryon density. These are the regions in which supernorvae and neutrons stars exist. For energies much higher, such as in RHIC, nuclei are transparent to each other and one can form a central region of almost zero baryon density, mostly pions, and very high temperature. This is the region of the early universe and the quark-gluon plasma. Design parameters and cost of the RHIC are discussed

PROCEEDINGS FROM RIKEN-BNL RESEARCH CENTER WORKSHOP: PARITY-VIOLATING SPIN ASYMMETRIES AT RHIC

International Nuclear Information System (INIS)

VOGELSANG, W.; PERDEKAMP, M.; SURROW, B.

2007-01-01

The RHIC spin program is now fully underway. Several runs have been successfully completed and are producing exciting first results. Luminosity and polarization have improved remarkably and promising advances toward the higher RHIC energy of √s = 500 GeV have been made. At this energy in particular, it will become possible to perform measurements of parity-violating spin asymmetries. Parity violation occurs in weak interactions, and in combination with the unique polarization capabilities at RHIC fascinating new opportunities arise. In particular, parity-violating single- and double-spin asymmetries give new insights into nucleon structure by allowing probes of up and down sea and anti-quark polarizations. Such measurements at RHIC are a DOE performance milestone for the year 2013 and are also supported by a very large effort from RIKEN. With transverse polarization, charged-current interactions may be sensitive to the Sivers effect. Parity-violating effects at RHIC have been proposed even as probes of physics beyond the Standard Model. With the era of measurements of parity-violating spin asymmetries at RHIC now rapidly approaching, we had proposed a small workshop that would bring together the main experts in both theory and experiment. We are very happy that this worked out. The whole workshop contained 17 formal talks, both experiment (10) and theory (7), and many fruitful discussions. The physics motivations for, the planned measurements were reviewed first. The RHIC machine prospects regarding polarized 500 GeV running were discussed, as well as the plans by the RHIC experiments for the vital upgrades of their detectors needed for the W physics program. We also had several talks on the topic of ''semi-inclusive deep-inelastic scattering'', which provides different access to related physics observables. On the theory side, new calculations were presented, for example in terms of QCD all-order resummations of perturbation theory. Also, new observables, such

Development of the Sandia Cooler

Energy Technology Data Exchange (ETDEWEB)

Johnson, Terry Alan [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Koplow, Jeffrey P. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Staats, Wayne Lawrence [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Curgus, Dita Brigitte [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Leick, Michael Thomas. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Matthew, Ned Daniel [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Zimmerman, Mark D. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Arienti, Marco [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Gharagozloo, Patricia E. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Hecht, Ethan S. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Spencer, Nathan A. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Vanness, Justin William. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Gorman, Ryan [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

2013-12-01

This report describes an FY13 effort to develop the latest version of the Sandia Cooler, a breakthrough technology for air-cooled heat exchangers that was developed at Sandia National Laboratories. The project was focused on fabrication, assembly and demonstration of ten prototype systems for the cooling of high power density electronics, specifically high performance desktop computers (CPUs). In addition, computational simulation and experimentation was carried out to fully understand the performance characteristics of each of the key design aspects. This work culminated in a parameter and scaling study that now provides a design framework, including a number of design and analysis tools, for Sandia Cooler development for applications beyond CPU cooling.

Status of the R and D Towards Electron Cooling of RHIC

International Nuclear Information System (INIS)

A. Favale; D. Holmes; J.J. Sredniawski; Hans Bluem; M.D. Cole; J. Rathke; T. Schultheiss; A.M.M. Todd; V.V. Parkhomchuk; V.B. Reva; J. Alduino; D.S. Barton; Dana Richard Beavis; I. Ben-Zvi; Michael Blaskiewicz; J.M. Brennan; Andrew Burrill; Rama Calaga; P. Cameron; X. Chang; K.A. Drees; A.V. Fedotov; W. Fischer; G. Ganetis; D.M. Gassner; J.G. Grimes; Hartmut Hahn; L.R. Hammons; A. Hershcovitch; H.C. Hseuh; D. Kayran; J. Kewisch; R.F. Lambiase; D.L. Lederle; Vladimir Litvinenko; C. Longo; W.W. MacKay; G.J. Mahler; G.T. McIntyre; W. Meng; B. Oerter; C. Pai; George Parzen; D. Pate; D. Phillips; S.R. Plate; Eduard Pozdeyev; Triveni Rao; J. Reich; Thomas Roser; A.G. Ruggiero; T. Russo; C. Schultheiss; Z. Segalov; J. Smedley; K. Smith; T. Tallerico; S. Tepikian; R. Than; R.J. Todd; Dejan Trbojevic; J.E. Tuozzolo; P. Wanderer; G. WANG; D. Weiss; Q. Wu; Kin Yip; A. Zaltsman; A. Burov; S. Nagaitsev; L.R. Prost; A.O. Sidorin; A.V. Smirnov; Yaroslav Derbenev; Peter Kneisel; John Mammosser; H. Phillips; Joseph Preble; Charles Reece; Robert Rimmer; Jeffrey Saunders; Mircea Stirbet; Haipeng Wang; A.V. Aleksandrov; D.L. Douglas; Y.W. Kang; D.T. Abell; G.I. Bell; David L. Bruhwiler; R. Busby; John R. Cary; D.A. Dimitrov; P. Messmer; Vahid Houston Ranjbar; D.S. Smithe; A.V. Sobol; P. Stoltz

2007-01-01

The physics interest in a luminosity upgrade of RHIC requires the development of a cooling-frontier facility. Detailed cooling calculations have been made to determine the efficacy of electron cooling of the stored RHIC beams. This has been followed by beam dynamics simulations to establish the feasibility of creating the necessary electron beam. Electron cooling of RHIC at collisions requires electron beam energy up to about 54 MeV at an average current of between 50 to 100 mA and a particularly bright electron beam. The accelerator chosen to generate this electron beam is a superconducting Energy Recovery Linac (ERL) with a superconducting RF gun with a laser-photocathode. An intensive experimental R and D program engages the various elements of the accelerator: Photocathodes of novel design, superconducting RF electron gun of a particularly high current and low emittance, a very high-current ERL cavity and a demonstration ERL using these components

Optimization of the Phase Advance Between RHIC Interaction Points

CERN Document Server

Tomas, Rogelio

2005-01-01

We consider the scenario of having two identical Interaction Points (IPs) in the Relativistic Heavy Ion Collider (RHIC). The strengths of beam-beam resonances strongly depend on the phase advance between these two IPs and therefore certain phase advances could improve beam lifetime and luminosity. We compute the dynamic aperture as function of the phase advance between these IPs to find the optimum settings. The beam-beam interaction is treated in the weak-strong approximation and a complete non-linear model of the lattice is used. For the current RHIC proton working point (0.69,0.685) the design lattice is found to have the optimum phase advance. However this is not the case for other working points.

The effect and correction of coupling generated by the RHIC triplet quadrupoles

International Nuclear Information System (INIS)

Pilat, F.; Peggs, S.; Tepikian, S.; Trbojevic, D.; Wei, J.

1995-01-01

This study explores the possibility of operating the nominal RHIC coupling correction system in local decoupling mode, where a subset of skew quadrupoles are independently set by minimizing the coupling as locally measured by beam position monitors. The goal is to establish a correction procedure for the skew quadrupole errors in the interaction region triplets that does not rely on a priori knowledge of the individual errors. After a description of the present coupling correction scheme envisioned for RHIC, the basics of the local decoupling method will be briefly recalled in the context of its implementation in the TEAPOT simulation code as well as operationally. The method is then applied to the RHIC lattice: a series of simple tests establish that single triplet skew quadrupole errors can be corrected by local decoupling. More realistic correction schemes are then studied in order to correct distributed sources of skew quadrupole errors: the machine can be decoupled either by pure local decoupling or by a combination of global (minimum tune separation) and local decoupling. The different correction schemes are successively validated and evaluated by standard RHIC simulation runs with the complete set of errors and corrections. The different solutions and results are finally discussed together with their implications for the hardware

Performance of an irreversible quantum Ericsson cooler at low temperature limit

International Nuclear Information System (INIS)

Wu Feng; Chen Lingen; Wu Shuang; Sun Fengrui

2006-01-01

The purpose of this paper is to investigate the effect of quantum properties of the working medium on the performance of an irreversible quantum Ericsson cooler with spin-1/2. The cooler is studied with the losses of heat resistance, heat leakage and internal irreversibility. The optimal relationship between the dimensionless cooling load R * versus the coefficient of performance ε for the irreversible quantum Ericsson cooler is derived. In particular, the performance characteristics of the cooler at the low temperature limit are discussed

Adjusting the IP $\\beta$ Functions in RHIC

CERN Document Server

Wittmer, W; Pilat, F; Ptitsyn, V; Van Zeijts, J

2004-01-01

The beta functions at the IP can be adjusted without perturbation of other optics functions via several approaches. In this paper we describe a scheme based on a vector knob, which assigns fixed values to the different tuning quadrupoles and scales them by a common multiplier. The values for the knob vector were calculated for a lattice without any errors using MADX. Previous studies for the LHC [1] have shown that this approach can meet the design goals. A specific feature of the RHIC lattice is the nested power supply system. To cope with the resulting problems a detailed response matrix analysis has been carried out and different sets of knobs were calculated and compared. The knobs were tested at RHIC during the 2004 run and preliminary results are discussed. Simultaneously a new approach to measure the beam sizes of both colliding beams at the IP, based on the tunability provided by the knobs, was developed and tested.

Design of the commissioning software for the AGS to RHIC transfer line

International Nuclear Information System (INIS)

Trahern, C.G.; Saltmarsh, C.; Satogata, T.; Kewisch, J.; Sathe, S.; D'ottavio, T.; Tepikian, S.; Shea, D.

1995-01-01

RHIC accelerator physicists and engineers have collaboratively specified the control system software for the commissioning of the AGS to RHIC transfer line (ATR) to occur in the fall of 1995. This paper summarizes the design and progress to date. The authors discuss the basic physics/engineering device model that they use to understand process and data flows, and describe the architecture and tools they will use to build the application level software

Isolation and characterization of cDNA encoding the 80-kDa subunit protein of the human autoantigen Ku (p70/p80) recognized by autoantibodies from patients with scleroderma-polymyositis overlap syndrome

International Nuclear Information System (INIS)

Mimori, Tsuneyo; Ohosone, Yasuo; Hama, Nobuaki; Suwa, Akira; Akizuki, Masashi; Homma, Mitsuo; Griffith, A.J.; Hardin, J.A.

1990-01-01

Anti-Ku (p70/p80) autoantibodies in patients with scleroderma-polymyositis overlap syndrome recognize a 70-kDa/80-kDa protein heterodimer which binds to terminal regions of double-stranded DNA. In the present study, the authors isolated full-length cDNAs that encode the 80-kDa Ku subunit. Initial screening of a human spleen cDNA library with anti-Ku antibodies yielded a cDNA of 1.0 kilobase (kb) (termed K71) encoding a portion of the 80-kDa Ku polypeptide (identification based on immunological criteria). In RNA blots, this cDNA hybridized with two mRNAs of 3.4 and 2.6 kb. In vitro transcription and translation experiments produced an immunoprecipitable polypeptide which comigrated with the 80-kDa Ku subunit. The Ku80-6 cDNA proved to be 3304 nucleotides in length, with an additional poly(A) tail, closely approximating the size of the larger mRNA. It contains a single long open reading frame encoding 732 amino acids. The putative polypeptide has a high content of acidic amino acids and a region with periodic repeat of leucine in every seventh position which may form the leucine zipper structure. In genomic DNA blots, probes derived from the opposite ends of cDNA Ku80-6 hybridized with several nonoverlapping restriction fragments from human leukocyte DNA, indicating that the gene encoding the 80-kDa Ku polypeptide is divided into several exons by intervening sequences

FIRST POLARIZED PROTON COLLISIONS AT RHIC

International Nuclear Information System (INIS)

ROSER, T.; AHRENS, L.; ALESSI, J.; BAI, M.; BEEBE-WANG, J.; BRENNAN, J.M.; BROWN, K.A.; BUNCE, G.; CAMERON, P.; COURANT, E.D.; DREES, A.; FISCHER, W.; FLILLER, R. III; GLENN, W.; HUANG, H.; LUCCIO, A.U.; MACKAY, W.W.; MAKDISI, Y.; MONTAG, C.; PILAT, F.; PTITSYN, V.; SATOGATA, T.

2002-01-01

We successfully injected polarized protons in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. Each snake consists of four helical superconducting dipoles which rotate the polarization by 180 o about a horizontal axis. This is the first time that polarized protons have been accelerated to 100 GeV

B factory at RHIC [Relativistic Heavy Ion Collider]?

International Nuclear Information System (INIS)

Lockyer, N.S.; Van Berg, R.; Newcomer, F.M.

1988-01-01

A dedicated B physics experiment located in the proposed Relativistic Heavy Ion Collider at Brookhaven (RHIC) is considered. The machine may operate in a p-p mode with a luminosity in excess of 10 32 cm/sup /minus/2/ sec/sup /minus/1/ at 250 /times/ 250 GeV. The estimated B/bar B/ cross section at these energies is about 10 μbarns and a run of 10 7 sec would produce roughly 10 10 B/bar B/ pairs. A comparison to similar ideas proposed for the Fermilab Tevatron Upgrade and the SSC are discussed. The most ambitious physics objective of such an experiment would be the study of CP nonconservation. Particular emphasis at this workshop was given to the self tagging mode B → K + π/sup /minus//. Experimental techniques developed during this experiment would be extremely useful for more ambitious projects anticipated at the SSC. 36 refs., 10 figs

Cryogenic laboratory (80 K - 4 K)

International Nuclear Information System (INIS)

Brad, Sebastian; Steflea, Dumitru

2002-01-01

The technology of low temperature at the beginning of this century, developed for the production of oxygen, nitrogen and rare gases, was the basis for setting up the cryogenic technology in all the companies with these activity fields. The cryogenics section of today comprises engineering and construction of cryogenic plants for science, research and development, space technology, nuclear power techniques. Linde has designed and built a reliable small scale Helium liquefier. This fully automatic cryoliquefier operates for purification, liquefaction as well as re-liquefaction of Helium-gas, evaporated in cryostat systems. The basic equipment of the Linde L5 are the liquefier apparatus, transfer line, medium pressure buffer vessel, automatic purifier, compressor with mechanical oil separation unit, oil adsorber, electrical control unit. The accessories of the Linde L5 are the liquid helium storage tank, high-pressure gas supply, helium recovery unit, and cryocomponents. The cycle compressor C 101 designed as a single stage screw compressor supplies the liquefaction process with approx. 10 g/s of helium at a pressure of 10 to 12 bar and a temperature of approx. 300 K. In the first plate heat exchanger E 201 the gas is cooled down to approx. 70 K. Then the He high-pressure flow is divided: about 7 g/s reach the turbine X 201 via valve 203 (turbine entry) and are expanded there to approx. 4.6 bar, the gas cooling down to 64 K. After further cooling in the heat exchanger E 203 to about 16 K, another power-consuming expansion to 1.2 bar takes place. The implied cooling of the gas results in a temperature of 12 K at the outlet of the turbine X 202. This gas is then transferred to the low-pressure side of the heat exchanger E 204. The smaller part of the He high-pressure gas flow (approx. 3 g/s) is cooled down in the heat exchanger E 202 - E 205 to about 7 K. One part of the cold helium gas (approx. 0.17 g/s) is used in the purifier to cool down the feed gas to air

Generalized z-scaling and pp collisions at RHIC

International Nuclear Information System (INIS)

Tokarev, Mikhail; Zborovsky, Imrich

2007-01-01

New generalization of the z-scaling in inclusive particle production is proposed. The scaling variable z is expressed in terms of the momentum fractions x 1 and x 2 of the incoming protons. Explicit dependence of z on the momentum fractions y a and y b of the scattered and recoil constituents carried by the inclusive particle and recoil object is included. The scaling function Ψ (z) for charged and identified hadrons produced in proton-proton collisions is constructed. The scheme allows unique description of data on inclusive cross sections of charged hadrons, pions, kaons, antiprotons and lambdas produced at RHIC energies. The obtained results suggest that the z-scaling may be used as a tool for searching for new physics phenomena of particle production in high transverse momentum and high multiplicity region at proton-proton colliders RHIC and LHC. (author)

ADVANCEMENT OF THE RHIC BEAM ABORT KICKER SYSTEM

International Nuclear Information System (INIS)

ZHANG, W.; AHRENS, L.; MI, J.; OERTER, B.; SANDBERG, J.; WARBURTON, D.

2003-01-01

As one of the most critical system for RHIC operation, the beam abort kicker system has to be highly available, reliable, and stable for the entire operating range. Along with the RHIC commission and operation, consistent efforts have been spend to cope with immediate issues as well as inherited design issues. Major design changes have been implemented to achieve the higher operating voltage, longer high voltage hold-off time, fast retriggering and redundant triggering, and improved system protection, etc. Recent system test has demonstrated for the first time that both blue ring and yellow ring beam abort systems have achieved more than 24 hours hold off time at desired operating voltage. In this paper, we report break down, thyratron reverse arcing, and to build a fast re-trigger system to reduce beam spreading in event of premature discharge

Status of superconducting magnet development (SSC, RHIC, LHC)

International Nuclear Information System (INIS)

Wanderer, P.

1993-01-01

This paper summarizes recent superconducting accelerator magnet construction and test activities at the Superconducting Super Collider Laboratory (SSC), the Large Hardon Collider at CERN (LHC), and the Relativistic Heavy Ion Collider at Brookhaven (RHIC). Future plans are also presented

Status of superconducting magnet development (SSC, RHIC, LHC)

International Nuclear Information System (INIS)

Wanderer, P.

1993-01-01

This paper summarize recent superconducting accelerator magnet construction and test activities at the Superconducting Super Collider Laboratory (SSC), the Large Hadron Collider at CERN (LHC), and the Relativistic Heavy Ion Collider at Brookhaven (RHIC). Future plan are also presented

Surface emission of quark gluon plasma at RHIC and LHC

International Nuclear Information System (INIS)

Xiang Wenchang; Wan Renzhou; Zhou Daicui

2008-01-01

Within the framework of a factorization model, we study the behaviour of nuclear modification factor in Au-Au collisions at RHIC and Pb-Pb collisions at LHC. We find that the nuclear modification factor is inversely proportional to the radius of the quark-gluon plasma and is dominated by the surface emission of hard jets. We predict the nuclear modification factor P AALHS ∼0.15 in central Pb-Pb collisions at LHC. The study shows that the factorization model can be used to describe the centrality dependence of nuclear modification factor of the high transverse momentum particles produced in heavy ion collisions at both RHIC and LHC. (authors)

MEASURED TRANSVERSE COUPLING IMPEDANCE OF RHIC INJECTION AND ABORT KICKERS

International Nuclear Information System (INIS)

HAHN, H.; DAVINO, D.

2001-01-01

Concerns regarding possible transverse instabilities in RHIC and the SNS pointed to the need for measurements of the transverse coupling impedance of ring components. The impedance of the RHIC injection and abort kicker was measured using the conventional method based on the S 21 forward transmission coefficient. A commercial 450 Ω twin-wire Lecher line were used and the data was interpreted via the log-formula. All measurements, were performed in test stands fully representing operational conditions including pulsed power supplies and connecting cables. The measured values for the transverse coupling impedance in kick direction and perpendicular to it are comparable in magnitude, but differ from Handbook predictions

PHENIX EXPERIMENT AT RHIC: DECADAL PLAN 2004-2013

International Nuclear Information System (INIS)

ZAJC, W.

2003-01-01

achievable using the present capabilities of PHENIX experimental apparatus, but the physics reach is considerably extended and the program made even more compelling by a proposed set of upgrades which include: (1) An aerogel and time-of-flight system to provide complete π/K/p separation for momenta up to 10 GeV/c. (2) A vertex detector to detect displaced vertices from the decay of mesons containing charm or bottom quarks. (3) A hadron-blind detector to detect and track electrons near the vertex. (4) A micro-TPC to extend the range of PHENIX tracking in azimuth and pseudo-rapidity. (5) A forward detector upgrade for an improved muon trigger to preserve sensitivity at the highest projected RHIC luminosities. (6) A forward calorimeter to provide photon+jet studies over a wide kinematic range. The success of the proposed program is contingent upon several factors external to PHENIX. Implementation of the upgrades is predicated on the availability of R and D funds to develop the required detector technologies on a timely, and in some cases urgent, basis. The necessity for such funding, and the physics merit of the proposed PHENIX program, has been endorsed in the first meeting of BNL's Detector Advisory Committee in December, 2002. Progress towards the physics goals depends in an essential way on the development of the design values for RHIC luminosity, polarization and availability. An analysis based on the guidance from the Collider Accelerator Department indicates that moderate increases in the yearly running time lead to very considerable increases in progress toward the enunciated goals. Efficient access to the rarest probes in the proposed program is achieved via the order-of-magnitude increase in luminosity provided by RHIC-II

PHENIX EXPERIMENT AT RHIC: DECADAL PLAN 2004-2013

Energy Technology Data Exchange (ETDEWEB)

ZAJC,W.ET. AL.

2003-11-30

program is achievable using the present capabilities of PHENIX experimental apparatus, but the physics reach is considerably extended and the program made even more compelling by a proposed set of upgrades which include: (1) An aerogel and time-of-flight system to provide complete {pi}/K/p separation for momenta up to 10 GeV/c. (2) A vertex detector to detect displaced vertices from the decay of mesons containing charm or bottom quarks. (3) A hadron-blind detector to detect and track electrons near the vertex. (4) A micro-TPC to extend the range of PHENIX tracking in azimuth and pseudo-rapidity. (5) A forward detector upgrade for an improved muon trigger to preserve sensitivity at the highest projected RHIC luminosities. (6) A forward calorimeter to provide photon+jet studies over a wide kinematic range. The success of the proposed program is contingent upon several factors external to PHENIX. Implementation of the upgrades is predicated on the availability of R&D funds to develop the required detector technologies on a timely, and in some cases urgent, basis. The necessity for such funding, and the physics merit of the proposed PHENIX program, has been endorsed in the first meeting of BNL's Detector Advisory Committee in December, 2002. Progress towards the physics goals depends in an essential way on the development of the design values for RHIC luminosity, polarization and availability. An analysis based on the guidance from the Collider Accelerator Department indicates that moderate increases in the yearly running time lead to very considerable increases in progress toward the enunciated goals. Efficient access to the rarest probes in the proposed program is achieved via the order-of-magnitude increase in luminosity provided by RHIC-II.

Scientific articles of the RBRC/CCAST Symposium on Spin Physics Lattice QCD and RHIC Physics

International Nuclear Information System (INIS)

2003-01-01

This volume comprises scientific articles of the symposium on spin physics, lattice QCD and RHIC physics organized by RIKEN BNL research center (RBRC) and China center of advanced science and technology (CCAST). The talks were discussing the spin structure of nucleons and other problems of RHIC physics

CONTINUOUS ABORT GAP CLEANING AT RHIC

International Nuclear Information System (INIS)

DREES, A.; FLILLER, R.III.; FU, W.; MICHNOFF, R.

2004-01-01

Since the RHIC Au-Au run in the year 2001 the 200 MHz cavity system was used at storage and a 28 MHz system during injection and acceleration. The rebucketing procedure potentially causes a higher debunching rate of heavy ion beams in addition to amplifying debunching due to other mechanisms. At the end of a four hour store, debunched beam can easily account for more than 50% of the total beam intensity. This effect is even stronger with the achieved high intensities of the RHIC Au-Au run in 2004. A beam abort at the presence of a lot of debunched beam bears the risk of magnet quenching and experimental detector damage due to uncontrolled beam losses. Thus it is desirable to avoid any accumulation of debunched beam from the beginning of each store, in particular to anticipate cases of unscheduled beam aborts due to a system failure. A combination of a fast transverse kickers and the new 2-stage copper collimator system are used to clean the abort gap continuously throughout the store with a repetition rate of 1 Hz. This report gives. an overview of the new gap cleaning procedure and the achieved performance

Doubling-resolution analog-to-digital conversion based on PIC18F45K80

Directory of Open Access Journals (Sweden)

Yueyang Yuan

2014-08-01

Full Text Available Aiming at the analog signal being converted into the digital with a higher precision, a method to improve the analog-to-digital converter (ADC resolution is proposed and described. Based on the microcomputer PIC18F45K80 in which the internal ADC modules are embedded, a circuit is designed for doubling the resolution of ADC. According to the circuit diagram, the mathematical formula for calculating this resolution is derived. The corresponding software and print circuit board assembly is also prepared. With the experiment, a 13 bit ADC is achieved based on the 12 bit ADC module predesigned in the PIC18F45K80.

ENERGY STAR Certified Water Coolers

Data.gov (United States)

U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 2.0 ENERGY STAR Program Requirements for Water Coolers that are effective as of February...

Consideration of heat transfer performance of helium-gas/water coolers in HENDEL

International Nuclear Information System (INIS)

Inagaki, Yoshiyuki; Miyamoto, Yoshiaki

1986-10-01

The helium engineering loop (HENDEL) has four helium-gas/water coolers, where the cooling water flows in the tubes and the helium gas flows on the shell side. Their cooling performance depends on mainly the heat transfer of helium gas on the shell side. This report describes the operational data of the coolers and the consideration of the heat transfer performance which is important for the design of coolers. It becomes clear that Donohue's equation is close to the operational data and conservative for the segmental baffle type cooler and preduction by Fishenden-Saunders or Zukauskas' equation is conservation for the step-up baffle type cooler. (author)

HOM Consideration of 704 MHz and 2.1 GHz Cavities for LEReC Linac

Energy Technology Data Exchange (ETDEWEB)

Xiao, Binping [RIKEN BNL; Belomestnykh, Sergey [SUNY, Stony Brook; Ben-Zvi, Ilan [RIKEN BNL; Blaskiewicz, Michael [RIKEN BNL; Brennan, Joseph [RIKEN BNL; Brutus, Jean Clifford [RIKEN BNL; Fedotov, Alexei [RIKEN BNL; Hahn, Harald [RIKEN BNL; McIntyre, Gary [RIKEN BNL; Pai, Chien [RIKEN BNL; Smith, Kevin [RIKEN BNL; Tuozzolo, Joseph [RIKEN BNL; Veshcherevich, Vadim [Cornell U., CLASSE; Wu, Qiong [RIKEN BNL; Xin, Tianmu [RIKEN BNL; Xu, Wencan [RIKEN BNL; Zaltsman, Alex [RIKEN BNL

2016-06-01

To improve RHIC luminosity for heavy ion beam energies below 10 GeV/nucleon, the Low Energy RHIC electron Cooler (LEReC) is currently under development at BNL. The Linac of LEReC is designed to deliver 2 MV to 5 MV electron beam, with rms dp/p less than 5·10⁻⁴. The HOM in this Linac is carefully studied to ensure this specification.

Low Energy Electron Cooler for NICA Booster

CERN Document Server

Denisov, A P

2017-01-01

BINP has developed an electron cooler to increase the ion accumulation efficiency in the NICA (Nuclotron-based Ion Collider fAcility) heavy ion booster (JINR, Dubna). Adjustment of the cooler magnetic system provides highly homogeneous magnetic field in the cooling section B trans/B long ≤ 4∙10-5 which is vital for efficient electron cooling. First experiments with an electron beam performed at BINP demonstrated the target DC current of 500 mA and electron energy 6 keV.

Microsystem Cooler Concept Developed and Being Fabricated

Science.gov (United States)

Moran, Matthew E.

2005-01-01

A patented microsystem cooler concept has been developed by the NASA Glenn Research Center. It incorporates diaphragm actuators to produce the Stirling refrigeration cycle within a planar configuration compatible with the thermal management of electronics, sensors, optical and radiofrequency systems, microarrays, and other microsystems. The microsystem cooler is most suited to volume-limited applications that require cooling below the ambient or sink temperature. Johns Hopkins University Applied Physics Laboratory is conducting development testing and fabrication of a prototype under a grant from Glenn.

Trypanosoma cruzi 80 kDa prolyl oligopeptidase (Tc80 as a novel immunogen for Chagas disease vaccine.

Directory of Open Access Journals (Sweden)

Augusto E Bivona

2018-03-01

Full Text Available Chagas disease, also known as American Trypanosomiasis, is a chronic parasitic disease caused by the flagellated protozoan Trypanosoma cruzi that affects about 8 million people around the world where more than 25 million are at risk of contracting the infection. Despite of being endemic on 21 Latin-American countries, Chagas disease has become a global concern due to migratory movements. Unfortunately, available drugs for the treatment have several limitations and they are generally administered during the chronic phase of the infection, when its efficacy is considered controversial. Thus, prophylactic and/or therapeutic vaccines are emerging as interesting control alternatives. In this work, we proposed Trypanosoma cruzi 80 kDa prolyl oligopeptidase (Tc80 as a new antigen for vaccine development against Chagas disease.In a murine model, we analyzed the immune response triggered by different immunization protocols based on Tc80 and evaluated their ability to confer protection against a challenge with the parasite. Immunized mice developed Tc80-specific antibodies which were able to carry out different functions such as: enzymatic inhibition, neutralization of parasite infection and complement-mediated lysis of trypomastigotes. Furthermore, vaccinated mice elicited strong cell-mediated immunity. Spleen cells from immunized mice proliferated and secreted Th1 cytokines (IL-2, IFN-γ and TNF-α upon re-stimulation with rTc80. Moreover, we found Tc80-specific polyfunctional CD4 T cells, and cytotoxic T lymphocyte activity against one Tc80 MHC-I peptide. Immunization protocols conferred protection against a T. cruzi lethal challenge. Immunized groups showed a decreased parasitemia and higher survival rate compared with non-immunized control mice. Moreover, during the chronic phase of the infection, immunized mice presented: lower levels of myopathy-linked enzymes, parasite burden, electrocardiographic disorders and inflammatory cells.Considering that

Brahms Experiment at RHIC Day-1 Physics

International Nuclear Information System (INIS)

Videbaek, Flemming

1999-01-01

The BRAHMS experiment is designed to measure semi-inclusive spectra of charged hadron over a wide range of rapidity. It will yield information on particle production, both at central rapidity and in the baryon rich fragmentation region. The physics plans for measurements in the first year of running at RHIC are discussed

First turn around strategy for RHIC

International Nuclear Information System (INIS)

Milutinovic, J.; Ruggiero, A.G.

1991-06-01

We present a strategy for achieving the so-called first turn around in RHIC. The strategy is based on the same method we had proposed to correct a distorted closed orbit in RHIC, i.e., on a generalization of the local three-bump method. We found out that the method is very effective in passing the beam through a non-ideal, insufficiently known, machine. We tested that software on ten different Gaussian distributions of dominant orbit distorting lattice imperfections. The perturbed lattice was generated by the code PATRIS, which was also adapted to control the newly developed software. In all of the ten distributions the software was capable of passing the beam through in 2--3 injection attempts, at full sextupole strength. It was also determined that once the beam makes the first turn around and all the correctors are energized, it stays in the machine for at least several hundred turns that we had checked. The quality of the orbit, that was established in this way, was also found to be very good, i.e., the residual distortions at the places of large beta function were much less than one millimeter. With one or two monitors/correctors broken, the software established a first turn around without any extra difficulties. The quality of such orbit was, of course, somewhat degraded, especially around the broken devices. It was also observed that, in the process of actual closing, the beam develops free betatron oscillations in the amplitude range of 1--5 mm, which can be reduced either by changing the injection conditions to better match the actual closed orbit or by an appropriate damping device. The hardware proposed for RHIC is more than sufficient to meet the demands of the first turn controlling software. The maximum kick angle to be applied to the beam would require less than 2/3 of the corrector's top strength even at the top magnetic rigidity Bρ = 850 T·m, which means that the correctors will be performing an easy task at injection

Quadrupole beam-based alignment in the RHIC interaction regions

International Nuclear Information System (INIS)

Ziegler, J.; Satogata, T.

2011-01-01

Continued beam-based alignment (BBA) efforts have provided significant benefit to both heavy ion and polarized proton operations at RHIC. Recent studies demonstrated previously unknown systematic beam position monitor (BPM) offset errors and produced accurate measurements of individual BPM offsets in the experiment interaction regions. Here we describe the algorithm used to collect and analyze data during the 2010 and early 2011 RHIC runs and the results of these measurements. BBA data has been collected over the past two runs for all three of the active experimental IRs at RHIC, updating results from the 2005 run which were taken with incorrectly installed offsets. The technique was successfully applied to expose a systematic misuse of the BPM survey offsets in the control system. This is likely to benefit polarized proton operations as polarization transmission through acceleration ramps depends on RMS orbit control in the arcs, but a quantitative understanding of its impact is still under active investigation. Data taking is ongoing as are refinements to the BBA technique aimed at reducing systematic errors and properly accounting for dispersive effects. Further development may focus on non-triplet BPMs such as those located near snakes, or arc quadrupoles that do not have individually shunted power supplies (a prerequisite for the current method) and as such, will require a modified procedure.

SDRC I-DEAS and RHIC (Relativistic Heavy Ion Collider)

International Nuclear Information System (INIS)

Goggin, C.M.

1989-01-01

In August 1984, Brookhaven National Laboratory submitted a proposal to the Department of Energy (DOE) for the construction of a Relativistic Heavy Ion Collider (RHIC). Since then funding has continued for the detailed design of RHIC. The hardware for RHIC consists of two concentric rings of superconducting magnets in a 2.4 mile circumference with six intersections. Bunches of ions will travel in opposite directions in each of the two rings and eventually collide head on at one of the six intersections. The hardware design involves complicated facilities for liquid helium cryogens, cryostat design, and pipe systems. The greatest challenge however is the ion beam position relative to the geometric center of the rings. There are three hundred and seventy-two dipole magnets that are ten meters long and weigh 4300 Kg (4.5 tons) each. Each dipole must be positioned in the ring to ± 0.5 mm. In addition, there are four hundred and ninety-two quadrupole magnets that must be positioned to ± 0.1 mm which is a total position error. This total position error includes all the surveying and part tolerance. To accomplish this task requires detailed planning and design of the cryostats which contain each magnet and the tunnel assembly throughout the 2.4 mile circumference. The IDEAS' software package provides a way to analyze this large scale problem. 11 figs

THE COUPLING CORRECTION SYSTEM AT RHIC: RESULTS FOR THE RUN 2000 AND PLANS FOR 2001

International Nuclear Information System (INIS)

Pilat, F.; Fischer, W.; Peggs, S.; Ptitsyn, V.; Tepikian, S.

2001-01-01

The RHIC coupling correction system has been commissioned during the Year 2000 run, which marked the successful first year of operation of the machine. The RHIC coupling correction system is described with particular emphasis on its flexibility, which allows using both global and local coupling compensation techniques. Coupling measurements and correction data are presented for the RHIC Blue and Yellow rings, together with the procedure used to reduce the minimum tune separation to 0.001, the typical resolution for tune measurements during run 2000. They further demonstrate how local coupling compensation in the interaction region substantially reduces the strength of the skew quadrupole families used for global coupling compensation

Matter in extremis: Ultrarelativistic nuclear collisions at RHIC

Energy Technology Data Exchange (ETDEWEB)

Jacobs, Peter; Wang, Xin-Nian

2004-08-20

We review the physics of nuclear matter at high energy density and the experimental search for the Quark-Gluon Plasma at the Relativistic Heavy Ion Collider (RHIC). The data obtained in the first three years of the RHIC physics program provide several lines of evidence that a novel state of matter has been created in the most violent, head-on collisions of Au nuclei at {radical}s = 200 GeV. Jet quenching and global measurements show that the initial energy density of the strongly interacting medium generated in the collision is about two orders of magnitude larger than that of cold nuclear matter, well above the critical density for the deconfinement phase transition predicted by lattice QCD. The observed collective flow patterns imply that the system thermalizes early in its evolution, with the dynamics of its expansion consistent with ideal hydrodynamic flow based on a Quark-Gluon Plasma equation of state.

Matter in extremis: Ultrarelativistic nuclear collisions at RHIC

International Nuclear Information System (INIS)

Jacobs, Peter; Wang, Xin-Nian

2004-01-01

We review the physics of nuclear matter at high energy density and the experimental search for the Quark-Gluon Plasma at the Relativistic Heavy Ion Collider (RHIC). The data obtained in the first three years of the RHIC physics program provide several lines of evidence that a novel state of matter has been created in the most violent, head-on collisions of Au nuclei at √s = 200 GeV. Jet quenching and global measurements show that the initial energy density of the strongly interacting medium generated in the collision is about two orders of magnitude larger than that of cold nuclear matter, well above the critical density for the deconfinement phase transition predicted by lattice QCD. The observed collective flow patterns imply that the system thermalizes early in its evolution, with the dynamics of its expansion consistent with ideal hydrodynamic flow based on a Quark-Gluon Plasma equation of state

Overview of results from PHOBOS experiment at RHIC

Science.gov (United States)

Olszewski, Andrzej; PHOBOS Collaboration; Back, B. B.; Baker, M. D.; Barton, D. S.; Betts, R. R.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Corbo, J.; Decowski, M. P.; Garcia, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Henderson, C.; Hicks, D.; Hofman, D. J.; Holzman, B.; Hollis, R. S.; Hoyński, R.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Michaowski, J.; Mignerey, A. C.; Mülmenstädt, J.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Rafelski, M.; Rbeiz, M.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steadman, S. G.; Steinberg, P.; Stephans, G. S. F.; Stodulski, M.; Sukhanov, A.; Tang, J. L.; Teng, R.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wadsworth, B.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysouch, B.

2002-07-01

An overview of results for interactions of Au+Au ions at centre-of-mass energies of √sNN = 56, 130 and 200 GeV obtained by the PHOBOS collaboration at RHIC is given. Measurements of primary charged particle density near mid-rapidity indicate that particle production grows logarithmically with collision energy and faster than linearly with the number of interacting nucleons. Elliptic flow is found to be much stronger at RHIC than at SPS energy. The effect is strongest in peripheral events and decreases for more central collisions and emission angles |η| > 1. The measured anti-particle to particle ratios of production rates for pions, kaons and protons in central Au+Au interactions at √sNN = 130 GeV are compatible with the statistical model of particle production, showing an increasingly baryon-free region in mid-rapidity with the increase of collision energy.

Event generator for RHIC spin physics. Proceedings of RIKEN BNL Research Center workshop: Volume 11

International Nuclear Information System (INIS)

1998-01-01

A major objective of the workshop was to establish a firm collaboration to develop suitable event generators for the spin physics program at RHIC. With the completion of the Relativistic Heavy Ion Collider (RHIC) as a polarized collider a completely new domain of high-energy spin physics will be opened. The planned studies address the spin structure of the nucleon, tests of the standard model, and transverse spin effects in initial and final states. RHIC offers the unique opportunity to pursue these studies because of its high and variable energy, 50 ≤ √s ≤ 500 GeV, high polarization, 70%, and high luminosity, 2 x 10 32 cm -2 sec -1 or more at 500 GeV. To maximize the output from the spin program at RHIC, the understanding of both experimental and theoretical systematic errors is crucial. It will require full-fledged event generators, to simulate the processes of interest in great detail. The history of event generators shows that their development and improvement are ongoing processes taking place in parallel to the physics analysis by various experimental groups. The number of processes included in the generators has been increasing and the precision of their predictions is being improved continuously. This workshop aims at getting this process well under way for the spin physics program at RHIC, based on the first development in this direction, SPHINX

Measuring two-particle Bose-Einstein correlations with PHOBOS at sign RHIC

International Nuclear Information System (INIS)

Betts, R.; Barton, D.; Carroll, A.

1995-01-01

We present results of a simulation of the measurement of two-particle Bose-Einstein correlations in central Au-Au collisions with the PHOBOS detector at RHIC. This measurement is expected to yield information on the relevant time and distance scales in these collisions. As the space-time scale is directly connected with the equation of state governing the evolution of the particle source, this information will be essential in understanding the physics of nucleus-nucleus collisions at RHIC energies. We demonstrate that the PHOBOS detector has sufficient resolution and acceptance to distinguish a variety of physics scenarios

Detecting the anti-hypertriton and anti-helium-4 from the RHIC

Directory of Open Access Journals (Sweden)

Ma Yu-Gang

2014-03-01

Full Text Available Recent progress on the dectection of antimatter particles at RHIC is briefly reviewed. The observations of the anti-hypertriton (H¯⊼3${}_ \\mathbin{\\buildrel\\relbar \\over{\\smash{\\scriptstyle\\wedge}\\vphantom{_x}}} ^3\\overline {\\rm{H}} $and anti-helium-4 nuclei ( (4He¯, or α¯$\\left( {^4\\overline {{\\rm{He}}} ,\\,{\\rm{or}}\\,\\overline {\\rm{\\alpha }} } \\right$, or ᾱ from the RHIC-STAR Collaboration are highlighted. In addition, preliminary lifetime measurement of H¯Λ3${}_\\Lambda ^3\\overline {\\rm{H}} $ and energy dependence of strangeness population factor are presented. The mechanism of light antinuclei production is also discussed.

A Prototype Ionization Profile Monitor for RHIC

Energy Technology Data Exchange (ETDEWEB)

Connolly, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Cameron, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ryan, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Shea, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Sikora, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

1997-03-17

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Lab will accelerate and store beams of ions ranging from protons to gold nuclei. Transverse beam profiles will be obtained by measuring the distribution of free electrons formed by beam ionization of the residual gas. The electrons are swept from the beamline by a transverse electric field, amplified by a microchannel plate (MCP), and collected on a circuit board with strip anodes oriented parallel to the beam axis. A uniform magnetic field,parallel to the sweep electric field, counters the defocusing effects of space charge and recoil momentum. A single-plane prototype ionization profile montor (IPM) was installed near the end of the AGS-to-RHIC transfer line (ATR) and tested during the sextant commissioning rung. It measured vertical profiles of single bunches of Au nuclei with intensities of 0.6-1.0 x 10⁸ particles. These profiles are compared to profiles on a fluorescent screen (WF3) located 2m downstream from the IPM. This paper describes the detector and gives results from the beam test.

Microsystem Cooler Development

Science.gov (United States)

Moran, Matthew E.; Wesolek, Danielle M.; Berhane, Bruk T.; Rebello, Keith J.

2004-01-01

A patented microsystem Stirling cooler is under development with potential application to electronics, sensors, optical and radio frequency (RF) systems, microarrays, and other microsystems. The microsystem Stirling cooler is most suited to volume-limited applications that require cooling below the ambient or sink temperature. Primary components of the planar device include: two diaphragm actuators that replace the pistons found in traditional-scale Stirling machines; and a micro-regenerator that stores and releases thermal energy to the working gas during the Stirling cycle. The use of diaphragms eliminates frictional losses and bypass leakage concerns associated with pistons, while permitting reversal of the hot and cold sides of the device during operation to allow precise temperature control. Three candidate microregenerators were custom fabricated for initial evaluation: two constructed of porous ceramic, and one made of multiple layers of nickel and photoresist in an offset grating pattern. An additional regenerator was prepared with a random stainless steel fiber matrix commonly used in existing Stirling machines for comparison to the custom fabricated regenerators. The candidate regenerators were tested in a piezoelectric-actuated test apparatus designed to simulate the Stirling refrigeration cycle. In parallel with the regenerator testing, electrostatically-driven comb-drive diaphragm actuators for the prototype device have been designed for deep reactive ion etching (DRIE) fabrication.

High-pt and jet physics from RHIC to LHC

International Nuclear Information System (INIS)

Estienne, M.

2008-01-01

The observation of the strong suppression of high-pt hadrons in heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC) at BNL has motivated a large experimental program using hard probes to characterize the deconfined medium created. However, what can be denoted as 'leading particle' physics accessible at RHIC presents some limitations which motivate at higher energy the study of much more penetrating objects: jets. The gain in center-of-mass energy expected at the Large Hadron Collider (LHC) at CERN will definitively improve our understanding on how the energy is lost in the system, opening a major new window of study: the physics of jets on an event-by-event basis. We will concentrate on the expected performance for jet reconstruction in ALICE using the EMCal calorimeter.

Cooling performance of helium-gas/water coolers in HENDEL

International Nuclear Information System (INIS)

Inagaki, Yoshiyuki; Takada, Shoji; Hayashi, Haruyoshi; Kobayashi, Toshiaki; Ohta, Yukimaru; Shimomura, Hiroaki; Miyamoto, Yoshiaki

1994-01-01

The helium engineering demonstration loop (HENDEL) has four helium-gas/water coolers where the cooling water flows in the tubes and helium gas on the shell side. Their cooling performance was studied using the operational data from 1982 to 1991. The heat transfer of helium gas on the shell was obtained for segmental and step-up baffle type coolers. Also, the change with operation time was investigated. The cooling performance was lowered by the graphite powder released from the graphite components for several thousand hours and thereafter recovered because the graphite powder from the components was reduced and the powder in the cooler shell was blown off during the operation. (orig.)

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP, RHIC SPIN COLLABORATION MEETING VI, VOLUME 36

International Nuclear Information System (INIS)

BLAND, L.; SAITO, N.

2001-01-01

The sixth meeting of the RHIC Spin Collaboration (RSC) took place on October 1, 2001 at Brookhaven National Laboratory. RHIC is now in its second year of operation for physics production and the first polarized proton collision run at √s=200 GeV is expected to start in eight weeks. The RSC has developed a plan for this coming run through two previous meetings, RHIC Spin Physics III (August 3, 2000) and IV (October 13-14, 2000). We requested the following: two weeks of polarized proton studies in AGS, three weeks of polarized collider commissioning, and five weeks of polarized proton physics run. As a result, we have obtained all we asked and the above plans are implemented in the current operation schedule. The focus of the present meeting was to bring all involved in the RHIC Spin activities up-to-date on the progress of machine development, theory issues, and experimental issues. This meeting was right after the Program Advisory Committee (PAC) meeting and it started with the comments on the PAC discussion by Gerry Bunce, who was informed about the PAC deliberations by Tom Kirk. The PAC was fully supportive to complete the proposed spin program within the currently available budget for RHIC run 2 operations. Gerry further explained the expected luminosity to be ∫ Ldt = 0.5 pb -1 per week, reflecting the current machine status. The introductory session also had a talk from Werner Vogelsang that reviewed the progress in perturbative QCD theory focused on spin effects

Air liquide's space pulse tube cryocooler systems

Science.gov (United States)

Trollier, T.; Tanchon, J.; Buquet, J.; Ravex, A.

2017-11-01

Thanks to important development efforts completed with ESA funding, Air Liquide Advanced Technology Division (AL/DTA), is now in position to propose two Pulse Tube cooler systems in the 40-80K temperature range for coming Earth Observation missions such as Meteosat Third Generation (MTG), SIFTI, etc… The Miniature Pulse Tube Cooler (MPTC) is lifting up to 2.47W@80K with 50W compressor input power and 10°C rejection temperature. The weight is 2.8 kg. The Large Pulse Tube Cooler (LPTC) is providing 2.3W@50K for 160W input power and 10°C rejection temperature. This product is weighing 5.1 kg. The two pulse tube coolers thermo-mechanical units are qualified against environmental constraints as per ECSS-E-30. They are both using dual opposed pistons flexure bearing compressor with moving magnet linear motors in order to ensure very high lifetime. The associated Cooler Drive Electronics is also an important aspect specifically regarding the active control of the cooler thermo-mechanical unit during the launch phase and the active reduction of the vibrations induced by the compressor (partly supported by the French Agency CNES). This paper details the presentation of the two Pulse Tube Coolers together with the Cooler Drive Electronics aspects.

A simulation study of linear coupling effects and their correction in RHIC

International Nuclear Information System (INIS)

Parzen, G.

1992-11-01

This paper describes a possible skew quadrupole correction system for linear coupling for the RHIC92 lattice. A simulation study has been done for the correction system. Results are given for the performance of the correction system, and the required strength of the skew quadruple correctors. An important effect of linear coupling in RHIC is to shift the tune ν x ν y , sometimes called tune splitting. Most of this tune splitting can be corrected with a two family skew quadrupole correction system. For RHIC92, the same 2 family correction system will work for all likely choices of β*. This was not the case for the RHIC91 lattice where different families of correctors were needed for different β*. The tune splitting described above which is corrected with a 2 family correction system is driven primarily by the ν x - ν y harmonic of the skew quadrupole field given by the field multipole αl. There are several other effects of linear coupling present which are driven primarily by the ν x + ν y harmonics of the skew quadrupole field, αl. These include the following: (1) A higher order residual tune shift that remains after correction with the 2 family correction system. This tune shift is roughly quadratic in αl; (2) Possible large changes in the beta functions; (3) Possible increase in the beam size at injection due to the beta function distortion and the emittance distortion at injection

The PHENIX experiment at RHIC

Energy Technology Data Exchange (ETDEWEB)

Tonse, S.R.; Thomas, J.H.

1993-12-15

Later this decade the Relativistic Heavy Ion Collider (RHIC) will be built at Brookhaven National Laboratory. Its goal will be to accelerate and collide Au beams at 100 GeV/c in an attempt to create a Quark Gluon Plasma (QGP). The PHENIX detector aims to detect the QGP through its leptonic and hadronic signatures. We describe here its physics capabilities and the details of the apparatus designed to pick out rare leptonic signatures from among hadronic multiplicities of up to 1500 particles per unit of rapidity.

Differences in high $p_{t}$ meson production between CERN SPS and RHIC heavy ion collisions

CERN Document Server

Papp, G; Barnafoldi, G G; Yi Zhang; Fái, G; Papp, Gabor; Levai, Peter; Barnafoldi, Gergely G.; Zhang, Yi; Fai, George

2001-01-01

In this talk we present a perturbative QCD improved parton model calculation for light meson production in high energy heavy ion collisions. In order to describe the experimental data properly, one needs to augment the standard pQCD model by the transverse momentum distribution of partons ("intrinsic k/sub T/"). Proton-nucleus data indicate the presence of nuclear shadowing and multi-scattering effects. Further corrections are needed in nucleus-nucleus collisions to explain the observed reduction of the cross section. We introduce the idea of proton dissociation and compare our calculations with the SPS and RHIC experimental data. (18 refs).

Hydrodynamic analysis of anisotropic transverse flow at RHIC

International Nuclear Information System (INIS)

Hirano, Tetsufumi; Tsuda, Keiichi; Kajimoto, Kohei

2001-01-01

By using a (3+1)-dimensional relativistic hydrodynamic model, we estimate the magnitude of (differential) elliptic flow parameter υ 2 at the BNL-RHIC energy. We compare the centrality and the transverse momentum dependence of υ 2 with the experimental data observed by the STAR Collaboration. (author)

Overview of results from PHOBOS experiment at RHIC

CERN Document Server

Olszewski, A; Baker, M D; Barton, D S; Betts, R R; Bindel, R; Budzanowski, A; Busza, W; Carroll, A; Corbo, J; Decowski, M P; García, E; George, N; Gulbrandsen, K H; Gushue, S; Halliwell, C; Hamblen, J; Henderson, C; Hicks, D; Hofman, D J; Holzman, B; Hollis, R S; Holynski, R; Iordanova, A; Johnson, E; Kane, J L; Katzy, J; Khan, N; Kucewicz, W; Kulinich, P A; Kuo, C M; Lin, W T; Manly, S L; McLeod, D; Michalowski, J; Mignerey, A C; Mülmenstädt, J; Nouicer, R; Olszewski, A; Pak, R; Park, I C; Pernegger, H; Rafelski, M; Rbeiz, M; Reed, C; Remsberg, L P; Reuter, M; Roland, C; Roland, G; Rosenberg, L J; Sagerer, J; Sarin, P; Sawicki, P; Skulski, W; Steadman, S G; Steinberg, P; Stephans, G S F; Stodulski, M; Sukhanov, A; Tang, J L; Teng, R; Trzupek, A; Vale, C; van Nieuwenhuizen, G J; Verdier, R; Wadsworth, B; Wolfs, F L H; Wosiek, B; Wozniak, K; Wuosmaa, A H; Wyslouch, B

2002-01-01

An overview of results for interactions of Au+Au ions at centre-of- mass energies of square root s/sub NN/=56, 130 and 200 GeV obtained by the PHOBOS collaboration at RHIC is given. Measurements of the primary charged particle density near mid-rapidity indicate that particle production grows logarithmically with collision energy and faster than linearly with the number of interacting nucleons. Elliptic flow is found to be much stronger at RHIC than at SPS energy. The effect is strongest in peripheral events and decreases for more central collisions and emission angles $\\beta >1$. The measured anti-particle to particle ratios of production rates for pions, kaons and protons in central Au+Au interactions at square root s/sub NN/=130 GeV are compatible with the statistical model of particle production, showing an increasingly baryon-free region in mid-rapidity with the increase of collision energy. (16 refs).

Kaon interferometry as signal for the QCD phase transition at RHIC

International Nuclear Information System (INIS)

Bernard, S.; Maruhn, J.A.; Greiner, W.; Rischke, D.H.

1997-01-01

Pion and kaon correlations in relativistic nuclear collisions are studied in the framework of boost-invariant, cylindrically symmetric hydrodynamics. It is investigated how the inverse widths, R out , R side , of the two-particle correlation functions in out- and side-direction depend on the average transverse momentum K perpendicular to of the particle pair, the initial energy density ε 0 , and the equation of state of the system. The QCD transition leads to a time delay in the expansion of the system and consequently to an enhancement of the ratio R out /R side . This time-delay signal is found to be particularly strong for large average transverse momenta K perpendicular to ∝1 GeV and initial energy densities accessible at RHIC, ε 0 ∝10-20 GeV fm -3 . Neutral kaon pair correlation functions, which are not influenced by final state Coulomb effects and less contaminated by resonance decays than pion correlation functions, seem to be the ideal tool to detect this collective time-delay signature of the QCD transition. (orig.)

Technical assistance for the evaluation of fluid loop components (Peltier cooler)

Science.gov (United States)

Best, R.; Biemann, W.; Bosch, R.; Hingst, U.; Kreeb, H.; Mueller, W.

1980-07-01

The application of Peltier elements for refrigeration with source temperature control and heat rejection to a fluid loop was investigated using commercially available Peltier cooling elements. Peltier element performance with Peltier elements integrated into a cooler unit, investigation of possible temperature stabilization of the source side of the Peltier cooler arrangement, investigation of the necessary power supply and the power consumption for certain requirements for temperature range and heat load at the source, and investigation of mounting and integration aspects are discussed. Analytical calculations for the performance of Peltier elements in a cooler unit are relevant for a power supply, a temperature regulation system, and the design of bread board cooler unit.

Sodium flow distribution test of the air cooler tubes

International Nuclear Information System (INIS)

Uchida, Hiroyuki; Ohta, Hidehisa; Shimazu, Hisashi

1980-01-01

In the heat transfer tubes of the air cooler which is installed in the auxiliary core cooling system of the fast breeder prototype plant reactor ''Monju'', sodium freezing may be caused by undercooling the sodium induced by an extremely unbalanced sodium flow in the tubes. Thus, the sodium flow distribution test of the air cooler tubes was performed to examine the flow distribution of the tubes and to estimate the possibility of sodium freezing in the tubes. This test was performed by using a one fourth air cooler model installed in the water flow test facility. As the test results show, the flow distribution from the inlet header to each tube is almost equal at any operating condition, that is, the velocity deviation from normalized mean velocity is less than 6% and sodium freezing does not occur up to 250% air velocity deviation at stand-by condition. It was clear that the proposed air cooler design for the ''Monju'' will have a good sodium flow distribution at any operating condition. (author)

Ramp Management in RHIC

International Nuclear Information System (INIS)

Kewisch, J.; Van Zeijts, J.; Peggs, S.; Satogata, T.

1999-01-01

In RHIC, magnets and RF cavities are controlled by Wave Form Generators (WFGs), simple real time computers which generate the set points. The WFGs are programmed to change set points from one state to another in a synchrotronized way. Such transition is called a ''Ramp'' and consists of a sequence of ''stepping stones'' which contain the set point of every WFG controlled device at a point in time. An appropriate interpolation defines the set points between these stepping stones. This report describes the implementation of the ramp system. The user interface, tools to create and modify ramps, interaction with modeling tools and measurements and correction programs are discussed

RHIC electron lenses upgrades

Energy Technology Data Exchange (ETDEWEB)

Gu, X. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Altinbas, Z. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Bruno, D. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Binello, S. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Costanzo, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Drees, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Gassner, D. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Hock, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Hock, K. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Harvey, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Luo, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Marusic, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Mi, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Mernick, K. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Michnoff, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Miller, T. A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Pikin, A. I. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Samms, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Shrey, T. C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Schoefer, V. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Tan, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Than, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Thieberger, P. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; White, S. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

2015-05-03

In the Relativistic Heavy Ion Collider (RHIC) 100 GeV polarized proton run in 2015, two electron lenses were used to partially compensate for the head-on beam-beam effect for the first time. Here, we describe the design of the current electron lens, detailing the hardware modifications made after the 2014 commissioning run with heavy ions. A new electron gun with 15-mm diameter cathode is characterized. The electron beam transverse profile was measured using a YAG screen and fitted with a Gaussian distribution. During operation, the overlap of the electron and proton beams was achieved using the electron backscattering detector in conjunction with an automated orbit control program.

Theoretical perspective on RHIC [relativistic heavy ion collider] physics

International Nuclear Information System (INIS)

Dover, C.B.

1990-10-01

We discuss the status of the relativistic heavy ion collider (RHIC) project at Brookhaven, and assess some key experiments which propose to detect the signatures of a transient quark-gluon plasma (QGP) phase in such collisions. 24 refs

Proceedings of RIKEN BNL Research Center Workshop: Progress in High-pT Physics at RHIC

Energy Technology Data Exchange (ETDEWEB)

Bazilevsky, A.; Bland, L.; Vogelsang, W.

2010-03-17

This volume archives the presentations at the RIKEN BNL Research Center workshop 'Progress in High-PT Physics at RHIC', held at BNL in March 2010. Much has been learned from high-p{sub T} physics after 10 years of RHIC operations for heavy-ion collisions, polarized proton collisions and d+Au collisions. The workshop focused on recent progress in these areas by both theory and experiment. The first morning saw review talks on the theory of RHIC high-p{sub T} physics by G. Sterman and J. Soffer, and on the experimental results by M. Tannenbaum. One of the most exciting recent results from the RHIC spin program is the first observation of W bosons and their associated single-spin asymmetry. The new preliminary data were reported on the first day of our workshop, along with a theoretical perspective. There also were detailed discussions on the global analysis of polarized parton distributions, including the knowledge on gluon polarization and the impact of the W-data. The main topic of the second workshop day were single-transverse spin asymmetries and their analysis in terms of transverse-momentum dependent parton distributions. There is currently much interest in a future Drell-Yan program at RHIC, thanks to the exciting physics opportunities this would offer. This was addressed in some of the talks. There also were presentations on the latest results on transverse-spin physics from HERMES and BELLE. On the final day of the workshop, the focus shifted toward forward and small-x physics at RHIC, which has become a cornerstone of the whole RHIC program. Exciting new data were presented and discussed in terms of their possible implications for our understanding of strong color-field phenomena in QCD. In the afternoon, there were discussions of nuclear parton distributions and jet observables, among them fragmentation. The workshop was concluded with outlooks toward the near-term (LHC, JLab) and longer-term (EIC) future. The workshop has been a great success

Minimizing Contrast Medium Doses to Diagnose Pulmonary Embolism with 80-kVp Multidetector Computed Tomography in Azotemic Patients

Energy Technology Data Exchange (ETDEWEB)

Holmquist, F. (Dept. of Diagnostic Radiology, Malmoe Univ. Hospital, Univ. of Lund, Malmoe (Sweden)); Hansson, K.; Pasquariello, F. (Dept. of Internal Medicine, Lasarettet Trelleborg, Univ. of Lund, Trelleborg (Sweden)); Bjoerk, J. (Competence Center for Clinical Research, Univ. Hospital, Univ. of Lund, Lund (Sweden)); Nyman, U. (Dept. of Radiology, Lasarettet Trelleborg, Univ. of Lund, Trelleborg (Sweden))

2009-02-15

Background: In diagnosing acute pulmonary embolism (PE) in azotemic patients, scintigraphy and magnetic resonance imaging are frequently inconclusive or not available in many hospitals. Computed tomography is readily available, but relatively high doses (30-50 g I) of potentially nephrotoxic iodine contrast media (CM) are used. Purpose: To report on the diagnostic quality and possible contrast-induced nephropathy (CIN) after substantially reduced CM doses to diagnose PE in azotemic patients using 80-peak kilovoltage (kVp) 16-row multidetector computed tomography (MDCT) combined with CM doses tailored to body weight, fixed injection duration adapted to scan time, automatic bolus tracking, and saline chaser. Material and Methods: Patients with estimated glomerular filtration rate (eGFR) <50 ml/min were scheduled to undergo 80-kVp MDCT using 200 mg I/kg, and those with eGFR =50 ml/min, 120-kVp MDCT with 320 mg I/kg. Both protocols used an 80-kg maximum dose weight and a fixed 15-s injection time. Pulmonary artery density and contrast-to-noise ratio were measured assuming 70 Hounsfield units (HU) for a fresh clot. CIN was defined as a plasma creatinine rise >44.2 mumol/l from baseline. Results: 89/148 patients (63/68 females) underwent 80-/120-kVp protocols, respectively, with 95% of the examinations being subjectively excellent or adequate. Mean values in the 80-/120-kVp cohorts regarding age were 82/65 years, body weight 66/78 kg, effective mAs 277/117, CM dose 13/23 g I, pulmonary artery density 359/345 HU, image noise (1 standard deviation) 24/21 HU, contrast-to-noise ratio 13/13, and dose-length product 173/258 mGycm. Only 1/65 and 2/119 patients in the 80- and 120-kVp cohorts, respectively, with negative CT and no anticoagulation suffered non-fatal thromboembolism during 3-month follow-up. No patient developed CIN. Conclusion: 80-kVp 16-row MDCT with optimization of injection parameters may be performed with preserved diagnostic quality, using markedly reduced CM

DESCRIPTION OF THE RHIC SEQUENCER SYSTEM

International Nuclear Information System (INIS)

DOTTAVIO, T.; FRAK, B.; MORRIS, J.; SATOGATA, T.; VAN ZEIJTS, J.

2001-01-01

The movement of the Relativistic Heavy Ion Collider (RHIC) through its various states (eg. injection, acceleration, storage, collisions) is controlled by an application called the Sequencer. This program orchestrates most magnet and instrumentation systems and is responsible for the coordinated acquisition and saving of data from various systems. The Sequencer system, its software infrastructure, support programs, and the language used to drive it are discussed in this paper. Initial operational experience is also described

eRHIC ERL modeling in Zgoubi

International Nuclear Information System (INIS)

Meot, F.; Brooks, S.; Hao, Y.; Jing, Y.; Ptitsyn, V.; Trbojevic, D.; Tsoupas, N.

2016-01-01

This Note discusses on-going work regarding the modeling of eRHIC ERL in the ray-tracing code Zgoubi. The various pieces of the recirculator puzzle, their optical properties and their assemblage into an operational input data file in are addressed. The Note reports in particular on preparatory stages toward extensive end-to-end 6D polarized electron bunch transport simulations, which yield methods, as well a series of preliminary qualitative outcomes, discussed as well.

Study of containment air cooler capacity in steam air environment during accident conditions

International Nuclear Information System (INIS)

Kansal, M.; Mohan, N.; Bhawal, R.N.; Bajaj, S.S.

2002-01-01

Full text: The air coolers are provided for controlling the temperature in the reactor building during normal operation. These air coolers also serve as the main heat sink for the removal of energy from high enthalpy air-steam mixture expected in reactor building under accident conditions. A subroutine COOLER has been developed to estimate the heat removal rate of the air coolers at high temperature and steam conditions. The subroutine COOLER has been attached with the code PACSR (post accident containment system response) used for containment pressure temperature calculation. The subroutine was validated using design parameters at normal operating condition. A study was done to estimate the heat removal rate for some postulated accident conditions. The study reveals that, under accident conditions, the heat removal rate of air coolers increases several times compared with normal operating conditions

Experimental and Mathematical Analysis of Multilayer Insulation below 80 K

CERN Document Server

Chorowski, M; Parente, C; Riddone, G

2000-01-01

The Large Hadron Collider [1], presently under construction at CERN, will make an extensive use of multilayer insulation system (MLI). The total surface to be insulated will be of about 80000 m2. A mathematical model has been developed to describe the heat flux through MLI from 80 K to 4.2 K. The total heat flux between the layers is the result of three distinct heat transfer modes: radiation, residual gas conduction and solid conduction. The mathematical model enables prediction of MLI behavior with regard to different MLI parameters, such as gas insulation pressure, number of layers and boundary temperatures. The calculated values have been compared to the experimental measurements carried out at CERN. Theoretical and experimental results revealed to be in good agreement, especially for insulation vacuum between 10-5 Pa and 10-3 Pa.

Technology transfer for industrial production of superconducting magnets for the RHIC project at BNL

International Nuclear Information System (INIS)

Wanderer, P.; Anerella, M.D.; Greene, A.F.; Kelly, E.; Willen, E.

1994-01-01

Industrial production of superconducting magnets for the Relativistic Heavy Ion Collider (RHIC) has begun. The R ampersand D for the magnets was carried out at BNL. Following the award of built-to-print contracts, staff from the laboratory and the vendors worked toward transferring both design principles and practical details to an industrial framework for cost effective production. All magnets made thus far have been acceptable for use in RHIC

Operations and Performance of RHIC as a Cu-Cu Collider

CERN Document Server

Pilat, Fulvia Caterina; Bai, Mei; Barton, Donald; Beebe-Wang, Joanne; Blaskiewicz, Michael; Brennan, Joseph M; Bruno, Donald; Cameron, Peter; Connolly, Roger; De Long, Joseph; Drees, Angelika; Fischer, Wolfram; Ganetis, George; Gardner, Chris J; Glenn, Joseph; Harvey, Margaret; Hayes, Thomas; Hseuh Hsiao Chaun; Huang, Haixin; Ingrassia, Peter; Iriso, Ubaldo; Lee, Roger C; Litvinenko, Vladimir N; Luo, Yun; MacKay, William W; Marr, Gregory J; Marusic, Al; Michnoff, Robert; Montag, Christoph; Morris, John; Nicoletti, Tony; Oerter, Brian; Ptitsyn, Vadim; Roser, Thomas; Russo, Thomas; Sandberg, Jon; Satogata, Todd; Schultheiss, Carl; Tepikian, Steven; Tomas, Rogelio; Trbojevic, Dejan; Tsoupas, Nicholaos; Tuozzolo, Joseph; Vetter, Kurt; Zaltsman, Alex; Zeno, Keith; Zhang, S Y; Zhang, Wu

2005-01-01

The 5th year of RHIC operations, started in November 2004 and expected to last till June 2005, consists of a physics run with Cu-Cu collisions at 100 GeV/u followed by one with polarized protons at 100 GeV. We will address here overall performance of the RHIC complex used for the first time as a Cu-Cu collider, and compare it with previous operational experience with Au, PP and asymmetric d-Au collisions. We will also discuss operational improvements, such as a ?* squeeze to 85cm in the high luminosity interaction regions from the design value of 1m, system improvements and machine performance limitations, such as vacuum pressure rise, intra-beam scattering, and beam beam interaction.

RHIC Workshop: experiments for a relativistic heavy ion collider

International Nuclear Information System (INIS)

Haustein, P.E.; Woody, C.L.

1985-01-01

Separate abstracts were prepared for individual papers in this workshop proceedings, covering such topics as: calorimeter-based experiments, dimuon detection, large magnetic spectrometers, experiments in the fragmentation region, two-photon physics, and theoretical questions relevant to experimental work at the RHIC

Thermal analysis for steering cooler and hose to reduce product design cost

International Nuclear Information System (INIS)

Wang, L.

2002-01-01

This paper describes the procedures to conduct a thermal analysis to determine the right sizing of a typical steering cooler and hose system. A commercial CFD (Computational Fluid Dynamics) package, Star-CD, was used to solve the heat transfer problem. Instead of modelling the actual finned cooler, a porous media box cooler was simulated in the analysis and the effective conductivity for the box cooler was obtained through the simulation of a submodel, which was consisted of one layer of the aluminium fin and two layers of air around it. A user-defined subroutine was used in the simulation to correctly represent the contact area in the box cooler. In addition, a comparison between the numerical results and the experimental testing was provided. The good agreement between them validates the methodology used in this analysis. (author)

LEPTON AND PHOTON PHYSICS AT RHIC

International Nuclear Information System (INIS)

TANNENBAUM, M.J.

2003-01-01

Results on physics at RHIC using outgoing leptons and photons will be presented from Au+Au collisions at nucleon-nucleon c.m. energies √(sNN) = 130 GeV and 200 GeV, and from p-p collisions at √(sNN) = 200 GeV. Introduction and motivation will be presented both from the theoretical and experimental perspectives. Topics include open charm production via single e ± , J/Ψ → e + + e - , μ + + μ - and inclusive photon production

Calculations of air cooler for new subsonic wind tunnel

Science.gov (United States)

Rtishcheva, A. S.

2017-10-01

As part of the component development of TsAGI’s new subsonic wind tunnel where the air flow velocity in the closed test section is up to 160 m/sec hydraulic and thermal characteristics of air cooler are calculated. The air cooler is one of the most important components due to its highest hydraulic resistance in the whole wind tunnel design. It is important to minimize its hydraulic resistance to ensure the energy efficiency of wind tunnel fans and the cost-cutting of tests. On the other hand the air cooler is to assure the efficient cooling of air flow in such a manner as to maintain the temperature below 40 °C for seamless operation of measuring equipment. Therefore the relevance of this project is driven by the need to develop the air cooler that would demonstrate low hydraulic resistance of air and high thermal effectiveness of heat exchanging surfaces; insofar as the cooling section must be given up per unit time with the amount of heat Q=30 MW according to preliminary evaluations. On basis of calculation research some variants of air cooler designs are proposed including elliptical tubes, round tubes, and lateral plate-like fins. These designs differ by the number of tubes and plates, geometrical characteristics and the material of finned surfaces (aluminium or cooper). Due to the choice of component configurations a high thermal effectiveness is achieved for finned surfaces. The obtained results form the basis of R&D support in designing the new subsonic wind tunnel.

How can the odderon be detected at RHIC and LHC?

Energy Technology Data Exchange (ETDEWEB)

Avila, R.F.; Gauron, P.; Nicolescu, B. [CNRS, Paris (France); Pierre et Marie Curie Univ., Paris (FR). Lab. de Physique Nucleaire et des Hautes Energies (LPNHE)

2007-01-15

The odderon remains an elusive object, 33 years after its invention. The odderon is now a fundamental object in QCD and it has to be found experimentally if QCD is right. In the present paper, we show how to find it at RHIC and LHC. The most spectacular signature of the odderon is the predicted difference between the differential cross-sections for proton-proton and antiproton-proton at high s and moderate t. This experiment can be done by using the STAR detector at RHIC and by combining these future data with the already present UA4/2 data. The odderon could also be found by the ATLAS experiment at LHC by performing a high-precision measurement of the real part of the hadron elastic scattering amplitude at small t. (orig.)

Bi-Sr-Ca-Cu-O superconductor system with critical temperatures of 80 and 107 K

International Nuclear Information System (INIS)

Kugimiya, K.; Kawashima, S.; Inoue, O.; Adachi, S.

1988-01-01

Critical temperatures (T/sub c/) of 80 and 107 K are confirmed by resistivity and inductance measurements and also by the Meissner effect. X-rayelectron diffraction and electron microscopy analyses on a single phase material of 80 K show that its structure is orthorhombic with a unit cell of a = 5.407 A, b = 27.011 A, c = 30.588 A composed of a pseudotetragonal cell of a = b = 5.41 A. The pseudotetragonal cell size and cleavage behavior to very thin flakes strongly indicate that the oxide is basically a lamellar oxide of the Aurivillius phase type, i.e., a stacked layer structure of (Bi 2 O 2 ) 2+ sheets and distorted perovskite cell sheets

Binary and ternary recombination of D3+ ions at 80-130 K: application of laser absorption spectroscopy.

Science.gov (United States)

Dohnal, Petr; Hejduk, Michal; Rubovič, Peter; Varju, Jozef; Roučka, Štěpán; Plašil, Radek; Glosík, Juraj

2012-11-21

Recombination of D(3)(+) ions with electrons at low temperatures (80-130 K) was studied using spectroscopic determination of D(3)(+) ions density in afterglow plasmas. The use of cavity ring-down absorption spectroscopy enabled an in situ determination of the abundances of the ions in plasma and the translational and the rotational temperatures of the recombining ions. Two near infrared transitions at (5792.70 ± 0.01) cm(-1) and at (5793.90 ± 0.01) cm(-1) were used to probe the number densities of the lowest ortho state and of one higher lying rotational state of the vibrational ground state of D(3)(+) ion. The results show that D(3)(+) recombination with electrons consists of the binary and the third-body (helium) assisted process. The obtained binary recombination rate coefficients are in agreement with a recent theoretical prediction for electron-ion plasma in thermodynamic equilibrium with α(bin)(80 K) = (9.2 ± 2.0) × 10(-8) cm(3) s(-1). The measured helium assisted ternary rate coefficients K(He) are in agreement with our previously measured flowing afterglow data giving a value of K(He)(80 K) = (1.2 ± 0.3) × 10(-25) cm(6) s(-1).

6D “Garren” snake cooler and ring cooler for µ{sup ±} cooling of a muon collider

Energy Technology Data Exchange (ETDEWEB)

Ding, X., E-mail: xding@bnl.gov [UCLA, Los Angeles, CA 90095 (United States); Berg, J.S. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Cline, D. [UCLA, Los Angeles, CA 90095 (United States); Garren, Al [Particle Beam Lasers, Inc., Northridge, CA 91324 (United States); Kirk, H.G. [Brookhaven National Laboratory, Upton, NY 11973 (United States)

2014-12-21

Six dimensional cooling of large emittance µ{sup +} and µ{sup −} beams is required in order to obtain the desired luminosity for a muon collider. In our previous study, we demonstrated that a 6D “Garren” ring cooler using both dipoles and solenoids in four 90{sup 0} achromatic arcs can give substantial cooling in all six phase space dimensions. In this paper, we describe the injection/extraction requirements of this four-sided ring. We also present the performance of an achromat-based 6D “Garren” snake cooler. The achromatic design permits the design to easily switch between a closed ring and a snaking geometry on injection or extraction from the ring.

INTENSITY DEPENDENT EFFECTS IN RHIC

International Nuclear Information System (INIS)

WEI, J.

1999-01-01

The Relativistic Heavy Ion Collider (RHIC) is currently under commissioning after a seven-year construction cycle. Unlike conventional hadron colliders, this machine accelerates, stores, and collides heavy ion beams of various combinations of species. The dominant intensity dependent effects are intra-beam scattering at both injection and storage, and complications caused by crossing transition at a slow ramp rate. In this paper, the authors present theoretical formalisms that have been used for the study, and discuss mechanisms, impacts, and compensation methods including beam cooling and transition jump schemes. Effects of space charge, beam-beam, and ring impedances are also summarized

Inter-cooler in solar-assisted refrigeration system: Theory and experimental verification

Directory of Open Access Journals (Sweden)

Zheng Hui-Fan

2015-01-01

Full Text Available An inter-cooler in the solar-assisted refrigeration system was investigated experimentally and theoretically, and the theoretical prediction was fairly in good agreement with the experimental data. The influence of pipe diameter, tooth depth, and spiral angle of inter-cooler on the performance of the refrigerant system was analyzed. It was concluded that heat transfer is influenced deeply by the structure parameters of inter-cooler, and the heat transfer capacity increases with tooth depth and spiral angle increasing, and decreases with tooth apex angle increasing.

Possible origin of RHIC Rout/Rsid HBT results

International Nuclear Information System (INIS)

Sandra S. Padula

2002-01-01

The effects of opacity of the nuclei together with a blackbody type of emission along the system history are considered as a means to explain the ratio R out =R sid observed by STAR and PHENIX collaborations at RHIC. Within our model, no flow is required to explain the data trend of this ratio for large surface emissivities

Possible origin of RHIC Rout/Rsid HBT results

International Nuclear Information System (INIS)

Padula, Sandra S.

2003-01-01

The effects of opacity of the nuclei together with a blackbody type of emission along the system history are considered as a means to explain the ratio R out /R sid observed by STAR and PHENIX collaborations at RHIC. Within our model, no flow is required to explain the data trend of this ratio for large surface emissivities

Jet Tomography versus Holography at RHIC and LHC

Directory of Open Access Journals (Sweden)

Torrieri G.

2011-04-01

Full Text Available We compare pQCD based jet tomography to AdS/CFT based jet holography approach to address the heavy quark jet puzzle and discuss future tests at RHIC and LHC that could help decide which paradigm can provide the most consistent quantitative theory to explain modification of jet observabkles in high energy nuclear collisions.

A simulation study of linear coupling effects and their correction in RHIC

International Nuclear Information System (INIS)

Parzen, G.

1993-01-01

This paper describes a possible skew quadrupole correction system for linear coupling effects for the RHIC92 lattice. A simulation study has been done for this correction system. Results are given for the performance of the correction system and the required strength of the skew quadrupole corrections. The location of the correctors is discussed. For RHIC92, it appears possible to use the same 2 family correction system for all the likely choices of β*. The simulation study gives results for the residual tune splitting that remains after correction with a 2 family correction system. It also gives results for the beta functions before and after correction

Spin transfers for baryon production in polarized pp collisions at RHIC-BNL

International Nuclear Information System (INIS)

Ma BoQiang; Schmidt, Ivan; Soffer, Jacques; Yang Jianjun

2002-01-01

We consider the inclusive production of longitudinally polarized baryons in p→p collisions at RHIC-BNL, with one longitudinally polarized proton. We study the spin transfer between the initial proton and the produced baryon as a function of its rapidity and we elucidate its sensitivity to the quark helicity distributions of the proton and to the polarized fragmentation functions of the quark into the baryon. We make predictions using an SU(6) quark spectator model and a perturbative QCD (pQCD) based model. We discuss these different predictions, and what can be learned from them, in view of the forthcoming experiments at RHIC-BNL

Long-range and head-on beam-beam compensation studies in RHIC with lessons for the LHC

International Nuclear Information System (INIS)

Fischer, W.; Luo, Y.; Abreu, N.; Calaga, R.; Montag, C.; Robert-Demolaize, G.; Dorda, U.; Koutchouk, J.-P.; Sterbini, G.; Zimmermann, F.; Kim, H.-J.; Sen, T.; Shiltsev, V.; Valishev, A.; Qiang, J.; Kabel, A.

2009-01-01

Long-range as well as head-on beam-beam effects are expected to limit the LHC performance with design parameters. They are also important consideration for the LHC upgrades. To mitigate long-range effects, current carrying wires parallel to the beam were proposed. Two such wires are installed in RHIC where they allow studying the effect of strong long-range beam-beam effects, as well as the compensation of a single long-range interaction. The tests provide benchmark data for simulations and analytical treatments. Electron lenses were proposed for both RHIC and the LHC to reduce the head-on beam-beam effect. We present the experimental long-range beam-beam program at RHIC and report on head-on compensations studies based on simulations

Report of the eRHIC Ring-Ring Working Group

Energy Technology Data Exchange (ETDEWEB)

Aschenauer, E. C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Berg, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brennan, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fedotov, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Litvinenko, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Montag, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Palmer, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Parker, B. [Brookhaven National Lab. (BNL), Upton, NY (United States); Peggs, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ptitsyn, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Trbojevic, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Willeke, F. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-10-13

This report evaluates the ring-ring option for eRHIC as a lower risk alternative to the linac-ring option. The reduced risk goes along with a reduced initial luminosity performance. However, a luminosity upgrade path is kept open. This upgrade path consists of two branches, with the ultimate upgrade being either a ring-ring or a linac-ring scheme. The linac-ring upgrade could be almost identical to the proposed linac-ring scheme, which is based on an ERL in the RHIC tunnel. This linac-ring version has been studied in great detail over the past ten years, and its significant risks are known. On the other hand, no detailed work on an ultimate performance ring-ring scenario has been performed yet, other than the development of a consistent parameter set. Pursuing the ring-ring upgrade path introduces high risks and requires significant design work that is beyond the scope of this report.

Reduction of beta* and increase of luminosity at RHIC

International Nuclear Information System (INIS)

Pilat, F.; Bai, M.; Bruno, D.; Cameron, P.; Della Penna, A.; Drees, A.; Litvinenko, V.; Luo, Y.; Malitsky, N.; Marr, G.; Ptitsyn, V.; Satogata, T.; Tepikian, S.; Trbojevic, D.

2009-01-01

The reduction of β* beyond the 1m design value at RHIC has been consistently achieved over the last 6 years of RHIC operations, resulting in an increase of luminosity for different running modes and species. During the recent 2007-08 deuteron-gold run the reduction to 0.70 from the design 1m achieved a 30% increase in delivered luminosity. The key ingredients allowing the reduction have been the capability of efficiently developing ramps with tune and coupling feedback, orbit corrections on the ramp, and collimation, to minimize beam losses in the final focus triplets, the main aperture limitations for the collision optics. We will describe the operational strategy used to reduce the β*, at first squeezing the beam at store, to test feasibility, followed by the operationally preferred option of squeezing the beam during acceleration, and the resulting luminosity increase. We will conclude with future plans for the beta squeeze

Upgrade of RHIC Vacuum Systems for High Luminosity Operation

CERN Document Server

Hseuh Hsiao Chaun; Smart, Loralie; Todd, Robert J; Weiss, Daniel

2005-01-01

With increasing ion beam intensity during recent RHIC operations, pressure rises of several decades were observed at most room temperature sections and at a few cold sections. The pressure rises are associated with electron multi-pacting, electron stimulated desorption and beam ion induced desorption and have been one of the major intensity and luminosity limiting factors for RHIC. Improvement of the warm sections has been carried out in the last few years. Extensive in-situ bakes, additional UHV pumping, anti-grazing ridges and beam tube solenoids have been implemented. Several hundred meters of NEG coated beam pipes have been installed and activated. Vacuum monitoring and interlock were enhanced to reduce premature beam aborts. Preliminary measures, such as pumping before cool down to reduce monolayer condensates, were also taken to suppress the pressure rises in the cold sections. The effectiveness of these measures in reducing the pressure rises during machine studies and during physics runs are discussed...

The strongly coupled quark-gluon plasma created at RHIC

CERN Document Server

Heinz, Ulrich W

2009-01-01

The Relativistic Heavy Ion Collider (RHIC) was built to re-create and study in the laboratory the extremely hot and dense matter that filled our entire universe during its first few microseconds. Its operation since June 2000 has been extremely successful, and the four large RHIC experiments have produced an impressive body of data which indeed provide compelling evidence for the formation of thermally equilibrated matter at unprecedented temperatures and energy densities -- a "quark-gluon plasma (QGP)". A surprise has been the discovery that this plasma behaves like an almost perfect fluid, with extremely low viscosity. Theorists had expected a weakly interacting gas of quarks and gluons, but instead we seem to have created a strongly coupled plasma liquid. The experimental evidence strongly relies on a feature called "elliptic flow" in off-central collisions, with additional support from other observations. This article explains how we probe the strongly coupled QGP, describes the ideas and measurements whi...

How robust will the RHIC lattice be during commissioning?

International Nuclear Information System (INIS)

Ohnuma, S.

1991-09-01

The question raised here is whether the RHIC lattice is robust enough to make all these commissioning manipulations possible. There are of course many factors involved in answering this question in a definitive manner. The purpose of this note is to see if there are any fundamental and serious shortcomings basic to the lattice. The lattice considered here is the one presented to the workshop by Steve Tepikian and called RHIC91. More specifically, we fix nine quadrupole parameters in all insertions except in the 6 o'clock insertion where the independent parameters is sixteen. The so-called perfect matching may require fourteen parameters instead of nine but the difference is insignificant. On the other hand, if the number of parameters is reduced from sixteen to nine in the 6 o'clock insertion, the mismatch in the arc beta function becomes non-trivial. For example, the horizontal beta may vary between 40m to 60m at QF locations

Transient Air Infiltration/Exfiltration in Walk-In Coolers

Energy Technology Data Exchange (ETDEWEB)

Faramarzi, Ramin [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Navaz, H. K. [Kettering University; Kamensky, K. [Michigan State University

2018-03-01

Walk-in coolers are room-sized, insulated, and refrigerated compartments for food product storage. Walk-ins have areas equal or below 280 m2 (3,000 ft2), and are classified either as coolers operating above 0 degrees C (32 degrees F) (medium-temperature) to store fresh fruit, vegetables, and dairy products, or freezers that operate below 0 degrees C (32 degrees F) (low-temperature) to meet health and safety standards of frozen food products. Walk-ins are typically found in restaurants as well as small- and medium-to-large grocery stores or supermarkets.

Laser pumping of ions in a cooler buncher

Energy Technology Data Exchange (ETDEWEB)

Cheal, B., E-mail: bradley.cheal@manchester.ac.uk [University of Manchester (United Kingdom); Baczynska, K. [University of Birmingham, School of Physics and Astronomy (United Kingdom); Billowes, J.; Campbell, P. [University of Manchester (United Kingdom); Eronen, T. [University of Jyvaeskylae, Department of Physics (Finland); Forest, D. H. [University of Birmingham, School of Physics and Astronomy (United Kingdom); Kessler, T.; Moore, I. D. [University of Jyvaeskylae, Department of Physics (Finland); Rueffer, M. [University of Birmingham, School of Physics and Astronomy (United Kingdom); Tordoff, B. [University of Manchester (United Kingdom); Tungate, G. [University of Birmingham, School of Physics and Astronomy (United Kingdom); Aystoe, J. [University of Jyvaeskylae, Department of Physics (Finland)

2008-01-15

Optical experiments at the IGISOL isotope separator facility, Jyvaeskylae, have for many years benefited from the introduction of an ion beam cooler. The device, a gas-filled RF quadrupole, reduces the emittance and longitudinal energy spread of the ion beam. Very recently, use has been made of the axial confinement of slowly travelling ions at the end of the cooler to redistribute the electronic populations through efficient laser excitation. Such a technique has proved beneficial to laser spectroscopic measurements and is a precursor to using the method to polarize the ion beam.

Radiation and contrast agent doses reductions by using 80-kV tube voltage in coronary computed tomographic angiography: A comparative study

Energy Technology Data Exchange (ETDEWEB)

Cao, Jian-xin [Department of Radiology, Wuhan 161th Hospital, Wuhan (China); Wang, Yi-min, E-mail: wym6669@yahoo.com.cn [Department of Radiology, Wuhan 161th Hospital, Wuhan (China); Lu, Jin-guo [Department of Cardiology, Asia Heart Hospital, Wuhan (China); Zhang, Yu; Wang, Peng; Yang, Cheng [Department of Radiology, Wuhan 161th Hospital, Wuhan (China)

2014-02-15

Objective: To investigate the effects of 80-kilovoltage (kV) tube voltage coronary computed tomographic angiography (CCTA) with a reduced amount of contrast agent on qualitative and quantitative image quality parameters and on radiation dose in patients with a body mass index (BMI) <23.0 kg/m{sup 2}. Methods: One hundred and twenty consecutive patients with a BMI <23.0 kg/m{sup 2} and a low calcium load undergoing retrospective electrocardiogram (ECG)-gated dual-source CCTA were randomized into two groups [standard-tube voltage (120-kV) vs. low-tube voltage (80-kV)]. The injection flow rate of contrast agent (350 mg I/mL) was adjusted to body weight of each patient (4.5–5.5 mL/s in the 120-kV group and 2.8–3.8 mL/s in the 80-kV group). Radiation and contrast agent doses were evaluated. Quantitative image quality parameters and figure of merit (FOM) of coronary artery were evaluated. Each coronary segment was evaluated for image quality on a 4-point scale. Results: Compared with the 120-kV group, effective dose and amount of contrast agent in the 80-kV group were decreased by 57.8% and 30.5% (effective dose:2.7 ± 0.5vs. 6.4 ± 1.3 mSv; amount of contrast agent:57.1 ± 3.2 vs. 82.1 ± 6.1 mL; both p < 0.0001), respectively. Image noise was 22.7 ± 2.1 HU for 120-kV images and 33.2 ± 5.2 HU for 80-kV images (p < 0.0001). Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in the proximal right coronary artery (RCA) and left main coronary artery (LMA) were all lower in 80-kV than 120-kV images (SNR in the proximal RCA: 16.5 ± 1.8 vs. 19.4 ± 2.8; SNR in the LMA: 16.3 ± 2.0 vs.19.6 ± 2.7; CNR in the proximal RCA: 19.4 ± 2.3 vs.22.9 ± 3.0; CNR in the LMA: 18.8 ± 2.4 vs. 22.7 ± 2.9; all p < 0.0001). FOM were all significantly higher in 80-kV than 120-kV images (proximal RCA: 146.7 ± 45.1 vs. 93.4 ± 32.0; LMA: 139.1 ± 47.2 vs. 91.6 ± 31.1; all p < 0.0001). There was no significant difference in image quality score between the two groups (3.3 ± 0

Radiation and contrast agent doses reductions by using 80-kV tube voltage in coronary computed tomographic angiography: A comparative study

International Nuclear Information System (INIS)

Cao, Jian-xin; Wang, Yi-min; Lu, Jin-guo; Zhang, Yu; Wang, Peng; Yang, Cheng

2014-01-01

Objective: To investigate the effects of 80-kilovoltage (kV) tube voltage coronary computed tomographic angiography (CCTA) with a reduced amount of contrast agent on qualitative and quantitative image quality parameters and on radiation dose in patients with a body mass index (BMI) <23.0 kg/m 2 . Methods: One hundred and twenty consecutive patients with a BMI <23.0 kg/m 2 and a low calcium load undergoing retrospective electrocardiogram (ECG)-gated dual-source CCTA were randomized into two groups [standard-tube voltage (120-kV) vs. low-tube voltage (80-kV)]. The injection flow rate of contrast agent (350 mg I/mL) was adjusted to body weight of each patient (4.5–5.5 mL/s in the 120-kV group and 2.8–3.8 mL/s in the 80-kV group). Radiation and contrast agent doses were evaluated. Quantitative image quality parameters and figure of merit (FOM) of coronary artery were evaluated. Each coronary segment was evaluated for image quality on a 4-point scale. Results: Compared with the 120-kV group, effective dose and amount of contrast agent in the 80-kV group were decreased by 57.8% and 30.5% (effective dose:2.7 ± 0.5vs. 6.4 ± 1.3 mSv; amount of contrast agent:57.1 ± 3.2 vs. 82.1 ± 6.1 mL; both p < 0.0001), respectively. Image noise was 22.7 ± 2.1 HU for 120-kV images and 33.2 ± 5.2 HU for 80-kV images (p < 0.0001). Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in the proximal right coronary artery (RCA) and left main coronary artery (LMA) were all lower in 80-kV than 120-kV images (SNR in the proximal RCA: 16.5 ± 1.8 vs. 19.4 ± 2.8; SNR in the LMA: 16.3 ± 2.0 vs.19.6 ± 2.7; CNR in the proximal RCA: 19.4 ± 2.3 vs.22.9 ± 3.0; CNR in the LMA: 18.8 ± 2.4 vs. 22.7 ± 2.9; all p < 0.0001). FOM were all significantly higher in 80-kV than 120-kV images (proximal RCA: 146.7 ± 45.1 vs. 93.4 ± 32.0; LMA: 139.1 ± 47.2 vs. 91.6 ± 31.1; all p < 0.0001). There was no significant difference in image quality score between the two groups (3.3 ± 0.8 vs. 3

OBSERVATION OF STRONG - STRONG AND OTHER BEAM - BEAM EFFECTS IN RHIC

International Nuclear Information System (INIS)

FISCHER, W.; BLASKIEWICZ, M.; BRENNAN, J.M.; CAMERON, P.; CONNOLLY, R.; MONTAG, C.; PEGGS, S.; PILAT, F.; PTITSYN, V.; TEPIKIAN, S.; TRBOJEVIC, D.; VAN ZEIJTS, J.

2003-01-01

RHIC is currently the only hadron collider in which strong-strong beam-beam effects can be seen. For the first time, coherent beam-beam modes were observed in a bunched beam hadron collider. Other beam-beam effects in RHIC were observed in operation and in dedicated experiments with gold ions, deuterons and protons. Observations include measurements of beam-beam induced tune shifts, lifetime and emittance growth measurements with and without beam-beam interaction, and background rates as a function of tunes. During ramps unequal radio frequencies in the two rings cause the crossing points to move longitudinally. Thus bunches experience beam-beam interactions only in intervals and the tunes are modulated. In this article we summarize the most important beam-beam observations made so far

sPHENIX: The next generation heavy ion detector at RHIC

Science.gov (United States)

Campbell, Sarah; sPHENIX Collaboration

2017-04-01

sPHENIX is a new collaboration and future detector project at Brookhaven National Laboratory’s Relativistic Heavy Ion Collider (RHIC). It seeks to answer fundamental questions on the nature of the quark gluon plasma (QGP), including its coupling strength and temperature dependence, by using a suite of precision jet and upsilon measurements that probe different length scales of the QGP. This is possible with a full acceptance, |η| superconducting magnet. With the increased luminosity afforded by accelerator upgrades, sPHENIX is going to perform high statistics measurements extending the kinematic reach at RHIC to overlap the LHC’s. This overlap is going to facilitate a better understanding of the role of temperature, density and parton virtuality in QGP dynamics and, specifically, jet quenching. This paper focuses on key future measurements and the current state of the sPHENIX project.

Resummed pQCD for $W^{+-}$ and $Z^{0}$ transverse momentum spectra at RHIC and LHC

CERN Document Server

Xiao Fei Zhang

2003-01-01

The transverse momentum distributions of W/sup +or-/ and Z/sup 0/ are predicted at RHIC and LHC. A resummation formalism with power corrections to the renormalization group equations is used. Shadowing effects are discussed and found to be unimportant at RHIC, but important for LHC. We study the enhancement of power corrections due to multiple scattering in nuclear collisions and numerically illustrate the weak effects of the dependence on the nuclear mass. (12 refs).

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ENTITLED "ODDERON SEARCHES AT RHIC" (VOLUME 76)

Energy Technology Data Exchange (ETDEWEB)

ORGANIZERS: GURYN, W.; KOVCHEGOV, Y.; VOGELSANG, W.; TRUEMAN, L.

2005-10-25

The Odderon, a charge-conjugation-odd partner of the Pomeron, has been a puzzle ever since its introduction in 1973. The Pomeron describes a colorless exchange with vacuum quantum numbers in the t-channel of hadronic scattering at high energies. The concept was originally formulated for the non-perturbative regime of Quantum Chromodynamics (QCD). In perturbation theory, the simplest picture of the Poineron is that of a two-gluon exchange process, whereas an Odderon can be thought of as an exchange of three gluons. Both the Pomeron and the Odderon are expected in QCD. However, while there exists plenty of experimental data that could be successfully described by Pomeron exchanges (for example in electron-proton and hadron-hadron scattering at high energies), no experimental sign of the Odderon has been observed. One of the very few hints so far is the difference in the diffractive minima of elastic proton-proton and proton-antiproton scattering measured at the ISR. The Odderon has recently received renewed attention by QCD researchers, mainly for the following two reasons. First of all, RHIC has entered the scene, offering exciting unique new opportunities for Odderon searches. RHIC provides collisions of nuclei at center-of-mass energies far exceeding those at all previous experiments. RHIC also provides collisions of protons of the highest center-of-mass energy, and in the interval, which has not been explored previously in p {bar p} collisions. In addition, it also has the unique feature of polarization for the proton beams, promising to become a crucial tool in Odderon searches. Indeed, theorists have proposed possible signatures of the Odderon in some spin asymmetries measurable at RHIC. Qualitatively unique signals should be seen in these observables if the Odderon coupling is large. Secondly, the Odderon has recently been shown to naturally emerge from the Color Glass Condensate (CGC), a theory for the high-energy asymptotics of QCD. It has been argued that

The Optimum Selection and Drawing Output Program Development of Shell and Tube Type Oil Cooler

International Nuclear Information System (INIS)

Lee, Y. B.; Kim, T. S.; Ko, J. M

2007-01-01

Shell and Tube type Oil Cooler is widely used for hydraulic presses, die casting machines, generation equipments, machine tools and construction heavy machinery. Temperature of oil in the hydraulic system changes viscosity and thickness of oil film. They have a bad effect to performance and lubrication of hydraulic machinery, so it is important to know exactly the heat exchanging efficiency of oil cooler for controlling oil temperature. But most Korean manufacturers do not have test equipment for oil cooler, so they cannot carry out the efficiency test of oil cooler and it is impossible to verify its performance. This paper includes information of construction of necessary utilities for oil cooler test and design and manufacture of test equipment. One can select the optimum product by obtaining performance data through tests of various kinds of oil coolers. And also the paper developed a program which can be easily used for design of 2D and 3D drawings of oil cooler

The performance evaluation of a micro/nano-scaled cooler working with an ideal Bose gas

International Nuclear Information System (INIS)

Guo, Juncheng; Su, Guozhen; Chen, Jincan

2012-01-01

Based on the size effect of a confined ideal Bose gas, the design concept of a quantum cooler is originally put forward. The cooler consists of two long tubes with the same length but different sizes of cross section, which are filled up with the ideal Bose gas, and is operated between two heat reservoirs. Expressions for the refrigeration rate and coefficient of performance (COP) of the cooler are derived. The effects of the size effect on the refrigeration rate and COP are discussed. The general performance characteristics of the cooler are revealed. -- Highlights: ► The design concept of a quantum cooler is originally put forward. ► Expressions for the refrigeration rate and coefficient of performance (COP) of the cooler are derived. ► The effects of the size effect on the refrigeration rate and COP are discussed. ► The general performance characteristics of the cooler are revealed. ► The results obtained are more general and significant than those in the current literature.

Dry coolers and air-condensing units (Review)

Science.gov (United States)

Milman, O. O.; Anan'ev, P. A.

2016-03-01

The analysis of factors affecting the growth of shortage of freshwater is performed. The state and dynamics of the global market of dry coolers used at electric power plants are investigated. Substantial increase in number and maximum capacity of air-cooled condensers, which have been put into operation in the world in recent years, are noted. The key reasons facilitating the choice of developers of the dry coolers, in particular the independence of the location of thermal power plant from water sources, are enumerated. The main steam turbine heat removal schemes using air cooling are considered, their comparison of thermal efficiency is assessed, and the change of three important parameters, such as surface area of heat transfer, condensate pump flow, and pressure losses in the steam exhaust system, are estimated. It is shown that the most effective is the scheme of direct steam condensation in the heat-exchange tubes, but other schemes also have certain advantages. The air-cooling efficiency may be enhanced much more by using an air-cooling hybrid system: a combination of dry and wet cooling. The basic applied constructive solutions are shown: the arrangement of heat-exchange modules and the types of fans. The optimal mounting design of a fully shopassembled cooling system for heat-exchange modules is represented. Different types of heat-exchange tubes ribbing that take into account the operational features of cooling systems are shown. Heat transfer coefficients of the plants from different manufacturers are compared, and the main reasons for its decline are named. When using evaporative air cooling, it is possible to improve the efficiency of air-cooling units. The factors affecting the faultless performance of dry coolers (DC) and air-condensing units (ACU) and the ways of their elimination are described. A high velocity wind forcing reduces the efficiency of cooling systems and creates preconditions for the development of wind-driven devices. It is noted that

Experimental testing of a small sorption air cooler using composite material made from natural siliceous shale and chloride

International Nuclear Information System (INIS)

Liu, Hongzhi; Nagano, Katsunori; Morita, Atsushi; Togawa, Junya; Nakamura, Makoto

2015-01-01

A sorption air cooler experimental setup including a reactor and fin tube condenser/evaporator was built. The reactor was developed with inner copper fins and dual layers of curing copper meshes. Composite material made by impregnating LiCl into the mesopores of Wakkanai Siliceous Shale (WSS) micropowders was packed between the intervals of two fins. Heat transfer was enhanced by the attached fins, and the dual layers of curing meshes installed between each interval of two fins were designed to improve the sorbate mass transfer. On the other hand, the fin-tube evaporator/condenser with fins outside is valuable for improving the convective heat transfer between the functional water inside the evaporator/condenser and the flowing outside heat transfer medium, air. The sorption capacity of the composite material increased dramatically after being impregnated with LiCl. Among the four tested samples, WSS + 40 wt% LiCl exhibits the best performance. A regeneration temperature of 80 °C appears to be optimal for obtaining both a high COP and high specific cooling power. A lower condensation temperature can increase the cooling power. The sorption and desorption times of 60 min yield a reasonable compromise between cooling COP and mass specific cooling powers. The developed sorption air cooler system using WSS + 40 wt% LiCl can store heat at temperatures below 100 °C and produce cooling energy with a cooling coefficient of performance (COP) of approximately 0.3. - Highlights: • Mesoporous composite material was developed using natural siliceous shale and LiCl. • Properties of the developed material were measured. • A sorption air cooler experimental setup including an inner-fin reactor and a fin tube condenser/evaporator was built. • The performance of the composite material in the sorption air cooler was examined. • The sorption air cooler system can produce cooling energy with a cooling COP around 0.3

Direct Evaporatrive Coolers of Gases and Liquids with Lowered Limit of Cooling

Directory of Open Access Journals (Sweden)

Doroshenko A.V.

2015-12-01

Full Text Available We have developed main technical solutions solution of indirect evaporative water and air coolers with reduced cooling limit. Packed part of heat-mass transfer devices is made of the film type based monoblock compositions of polymer materials. A mathematical model describing the processes of joint heat and mass transfer in evaporative coolers is executed. A comparative analysis of the possibilities of coolers designed based on experimental data on the efficiency of processes of heat and mass transfer.

and two-particle spectra at RHIC based on a hydrodynamical model

Indian Academy of Sciences (India)

parametrize the initial energy density distribution and net baryon number distribution as in figure 1. For both RHIC and ... Figure 2 shows pseudorapidity distribution of charged hadrons and transverse momen- ... Network Center. References.

COMMISSIONING SPIN ROTATORS IN RHIC

International Nuclear Information System (INIS)

MACKAY, W.W.; AHRENS, L.; BAI, M.; COURANT, E.D.; FISCHER, W.; HUANG, H.; LUCCIO, A.; MONTAG, C.; PILAT, F.; PTITSYN, V.; ROSER, T.; SATOGATA, T.; TRBOJEVIC, D.; VANZIEJTS, J.

2003-01-01

During the summer of 2002, eight superconducting helical spin rotators were installed into RHIC in order to control the polarization directions independently at the STAR and PHENIX experiments. Without the rotators, the orientation of polarization at the interaction points would only be vertical. With four rotators around each of the two experiments, we can rotate either or both beams from vertical into the horizontal plane through the interaction region and then back to vertical on the other side. This allows independent control for each beam with vertical, longitudinal, or radial polarization at the experiment. In this paper, we present results from the first run using the new spin rotators at PHENIX

RHIC heavy ion operations performance

CERN Document Server

Satogata, T; Ferrone, R; Pilat, F

2006-01-01

The Relativistic Heavy Ion Collider (RHIC) completed its fifth year of operation in 2005, colliding copper ion beams with ps=200 GeV/u and 62.4 GeV/u[1]. Previous heavy ion runs have collided gold ions at ps=130 GeV/u, 200 GeV/u, and 62.4 GeV/u[2], and deuterons and gold ions at ps=200 GeV/u[3]. This paper discusses operational performance statistics of this facility, including Cu- Cu delivered luminosity, availability, calendar time spent in physics stores, and time between physics stores. We summarize the major factors affecting operations efficiency, and characterize machine activities between physics stores.

The dipole corrector magnets for the RHIC fast global orbit feedback system

International Nuclear Information System (INIS)

Thieberger, P.; Arnold, L.; Folz, C.; Hulsart, R.; Jain, A.; Karl, R.; Mahler, G.; Meng, W.; Mernick, K.; Michnoff, R.; Minty, M.; Montag, C.; Ptitsyn, V.; Ritter, J.; Smart, L.; Tuozzolo, J.; White, J.

2011-01-01

The recently completed RHIC fast global orbit feedback system uses 24 small 'window-frame' horizontal dipole correctors. Space limitations dictated a very compact design. The magnetic design and modelling of these laminated yoke magnets is described as well as the mechanical implementation, coil winding, vacuum impregnation, etc. Test procedures to determine the field quality and frequency response are described. The results of these measurements are presented and discussed. A small fringe field from each magnet, overlapping the opposite RHIC ring, is compensated by a correction winding placed on the opposite ring's magnet and connected in series with the main winding of the first one. Results from measurements of this compensation scheme are shown and discussed.

RHIC spin physics: Proceedings. Volume 7

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-12-01

This proceedings compiles one-page summaries and five transparencies for each talk, with the intention that the speaker should include a web location for additional information in the summary. Also, email addresses are given with the participant list. The order follows the agenda: gluon, polarimetry, accelerator, W production and quark/antiquark polarization, parity violation searches, transversity, single transverse spin, small angle elastic scattering, and the final talk on ep collisions at RHIC. The authors begin the Proceedings with the full set of transparencies from Bob Jaffe`s colloquium on spin, by popular request.

RHIC spin physics: Proceedings. Volume 7

International Nuclear Information System (INIS)

1998-01-01

This proceedings compiles one-page summaries and five transparencies for each talk, with the intention that the speaker should include a web location for additional information in the summary. Also, email addresses are given with the participant list. The order follows the agenda: gluon, polarimetry, accelerator, W production and quark/antiquark polarization, parity violation searches, transversity, single transverse spin, small angle elastic scattering, and the final talk on ep collisions at RHIC. The authors begin the Proceedings with the full set of transparencies from Bob Jaffe's colloquium on spin, by popular request

B-physics at RHIC: An opportunity

International Nuclear Information System (INIS)

Atiya, M.S.; White, S.; Marx, M.

1994-01-01

B physics provides a unique window for investigation and confirmation of our picture of CP violation, as well as an opportunity to explore physics beyond the Standard Model. Because of this richness of physics, programs for the study of the B sector are in progress or under development at most of the major facilities for high energy physics in the world. In this note we suggest that a B program at the RHIC facility at BNL could provide timely and complementary information to our understanding of physics within and beyond the Standard Model

THE RHIC BEAM ABORT KICKER SYSTEM

International Nuclear Information System (INIS)

Hahn, H.

1999-01-01

THE ENERGY STORED IN THE RHIC BEAM IS ABOUT 200 KJ PER RING AT DESIGN ENERGY AND INTENSITY. TO PREVENT QUENCHING OF THE SUPERCONDUCTING MAGNETS OR MATERIAL DAMAGE, THE BEAM WILL BE SAFELY DISPOSED OF BY AN INTERNAL BEAM ABORT SYSTEM, WHICH INCLUDES THE KICKER MAGNETS, THE PULSED POWER SUPPLIES, AND THE DUMP ABSORBER. DISPOSAL OF HEAVY IONS, SUCH AS GOLD, IMPOSES DESIGN CONSTRAINTS MORE SEVERE THAN THOSE FOR PROTON BEAMS OF EQUAL INTENSITY. IN ORDER TO MINIMIZE THE THERMAL SHOCK IN THE CARBON-FIBER DUMP BLOCK, THE BUNCHES MUST BE LATERALLY DISPERSED

The ERL-based Design of Electron-Hadron Collider eRHIC

Energy Technology Data Exchange (ETDEWEB)

Ptitsyn, Vadim [et al.

2016-06-01

Recent developments of the ERL-based design of future high-luminosity electron-hadron collider eRHIC focused on balancing technological risks present in the design versus the design cost. As a result a lower risk design has been adopted at moderate cost increase. The modifications include a change of the main linac RF frequency, reduced number of SRF cavity types and modified electron spin transport using a spin rotator. A luminosity-staged approach is being explored with a Nominal design ($L \\sim 10^{33} {\\rm cm}^2 {\\rm s}^{-1}$) that employs reduced electron current and could possibly be based on classical electron cooling, and then with the Ultimate design ($L \\gt 10^{34} {\\rm cm}^{-2} {\\rm s}^{-1}$) that uses higher electron current and an innovative cooling technique (CeC). The paper describes the recent design modifications, and presents the full status of the eRHIC ERL-based design.

Half-length model of a Siberian Snake magnet for RHIC

CERN Document Server

Okamura, M; Kawaguchi, T; Katayama, T; Jain, A; Muratore, J; Morgan, G; Willen, E

2000-01-01

For the Relativistic Heavy Ion Collider (RHIC) Spin Project, super-conducting helical dipole magnets are being constructed. These magnets will be used in 'Siberian Snakes' and 'Spin Rotators', which manipulate spin direction of proton beams in RHIC. The dipole field in these magnets rotates 360 deg. and is required to reach a magnetic field strength of more than 4.0 T. The bore radius of the coils and the magnetic length of the magnets are 50 and 2400 mm, respectively. To ascertain the performance of these magnets, which are built using a new 'coil in a slot' technique, a half-length model has been fabricated and tested. The quench performance, field uniformity and rotation angle have been investigated. The measured values in the model magnet agreed well with field calculations. These results demonstrate the adequacy of the fabrication method adopted in the model magnet. (authors)

New challenges for HEP computing: RHIC [Relativistic Heavy Ion Collider] and CEBAF [Continuous Electron Beam Accelerator Facility

International Nuclear Information System (INIS)

LeVine, M.J.

1990-01-01

We will look at two facilities; RHIC and CEBF. CEBF is in the construction phase, RHIC is about to begin construction. For each of them, we examine the kinds of physics measurements that motivated their construction, and the implications of these experiments for computing. Emphasis will be on on-line requirements, driven by the data rates produced by these experiments

Evaporative Air Coolers Optimization for Energy Consumption Reduction and Energy Efficiency Ratio Increment

OpenAIRE

Leila Torkaman; Nasser Ghassembaglou

2015-01-01

Significant quota of Municipal Electrical Energy consumption is related to Decentralized Air Conditioning which is mostly provided by evaporative coolers. So the aim is to optimize design of air conditioners to increase their efficiencies. To achieve this goal, results of practical standardized tests for 40 evaporative coolers in different types collected and simultaneously results for same coolers based on one of EER (Energy Efficiency Ratio) modeling styles are figured ...

Consequences of warm-up of a sector above 80K

CERN Document Server

Strubin, P

2009-01-01

There may be circumstances when a sector has to be partially or totally warmed-up to temperatures above 80 K, that is when thermal dilatation starts to play a role. Some equipment have been identify as presenting a risk, like the non-conform "plug-in" modules in the arcs. Because of motion induced by thermal dilatation, the electrical (ElQA) quality control may also have to be done again after cool-down. The main reason identified so far for partial warm-up is the required maintenance of the cooling towers and the cryogenics plants. There is also the request from the vacuum group to periodically warm-up the beam screen to temperatures in the 100 K region to release and pump-out the gas crysorbed on the surface of the beam screen. Observed and expected temperature conditions and statistics on failures of PIMs in sectors which have been warmed-up will be presented in this contribution. Methods to detect buckled PIMs will be described, as well as a recommended strategy for consolidation. Finally, the required el...

Source of second order chromaticity in RHIC

International Nuclear Information System (INIS)

Luo, Y.; Gu, X.; Fischer, W.; Trbojevic, D.

2011-01-01

In this note we will answer the following questions: (1) what is the source of second order chromaticities in RHIC? (2) what is the dependence of second order chromaticity on the on-momentum β-beat? (3) what is the dependence of second order chromaticity on β* at IP6 and IP8? To answer these questions, we use the perturbation theory to numerically calculate the contributions of each quadrupole and sextupole to the first, second, and third order chromaticities.

NON-LINEAR MODELING OF THE RHIC INTERACTION REGIONS

International Nuclear Information System (INIS)

TOMAS, R.; FISCHER, W.; JAIN, A.; LUO, Y.; PILAT, F.

2004-01-01

For RHIC's collision lattices the dominant sources of transverse non-linearities are located in the interaction regions. The field quality is available for most of the magnets in the interaction regions from the magnetic measurements, or from extrapolations of these measurements. We discuss the implementation of these measurements in the MADX models of the Blue and the Yellow rings and their impact on beam stability

The development of a cryogenic integrated system with the working temperature of 100K

Science.gov (United States)

Liu, En'guang; Wu, Yi'nong; Wang, Yueming; Wen, Jiajia; Lv, Gang; Li, Chunlai; Hou, Jia; Yuan, Liyin

2016-05-01

In the infrared system, cooling down the optic components' temperature is a better choice to decrease the background radiation and maximize the sensitivity. This paper presented a 100K cryogenic optical system, for which an integrated designation of mechanical cooler, flexible thermal link and optical bench was developed. The whole infrared optic components which were assembled in a vacuum box were cooled down to 100K by two mechanical coolers. Low thermal conductivity supports and low emissivity multi-layers were used to reduce the cryogenic optical system's heat loss. The experiment results showed that in about eight hours, the temperature of the optical components reached 100K from room temperature, and the vibration from the mechanical coolers nearly have no affection to the imaging process by using of thermal links. Some experimental results of this cryogenic system will be discussed in this paper.

BEAM-BASED MEASUREMENTS OF PERSISTENT CURRENT DECAY IN RHIC

International Nuclear Information System (INIS)

FISCHER, W.; JAIN, A.; TEPIKIAN, S.

2001-01-01

The two RHIC rings are equipped with superconducting dipole magnets. At injection, induced persistent currents in these magnets lead to a sextupole component. As the persistent currents decay with time, the horizontal and vertical chromaticities change. From magnet measurements of persistent current decays, chromaticity changes in the machine are estimated and compared with chromaticity measurements

The gold flashlight: Coherent photons (and Pomerons) at RHIC

International Nuclear Information System (INIS)

Klein, S.; Scannapieco, E.

1997-06-01

The Relativistic Heavy Ion Collider (RHIC) will be the first heavy ion accelerator energetic enough to produce hadronic final states via coherent γγ, γP, and PP interactions. Because the photon flux scales as Z 2 , up to an energy of about γℎc/R ∼ 3 GeV/c, the γγ interaction rates are large. RHIC γP interactions test how Pomerons couple to nuclei and measure how different vector mesons, including the J/ψ, interact with nuclear matter. PP collisions can probe Pomeron couplings. Because these collisions can involve identical initial states, for identical final states, the γγ, γP, and PP channels may interfere, producing new effects. The authors review the physics of these interactions and discuss how these signals can be detected experimentally, in the context of the STAR detector. Signals can be separated from backgrounds by using isolation cuts (rapidity gaps) and p perpendicular. The authors present Monte Carlo studies of different backgrounds, showing that representative signals can be extracted with good rates and signal to noise ratios

Thermal transport properties of niobium and some niobium-based alloys from 80 to 1600 K

Energy Technology Data Exchange (ETDEWEB)

Moore, J P; Graves, R S; Williams, R K [Oak Ridge National Lab., TN (USA)

1980-01-01

The electric resistivity, rho, and Seebeck coefficient, S, of 99.8 at% niobium, and Nb-4.8 at% W, Nb-5 at% Mo, Nb-10 at% Mo, and Nb-2.4 at% Mo-2.4 at% Zr alloys were measured from 80 to 1600 K, and the thermal conductivity, lambda, of the niobium and the Nb-5 at% W alloy was measured from 80 to 1300 K. A technique is described for measuring rho and S of a specimen during radial-heat-flow measurements of lambda. The transport property results, which had uncertainties of +-0.4% for rho and +-1.4% for lambda, showed the influence of tungsten and molybdenum solutes on the transport properties of niobium and were used to obtain the electronic Lorenz function of pure niobium, which was found to approach the Sommerfeld value at high temperatures.

The PHOBOS perspective on discoveries at RHIC

Science.gov (United States)

Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Becker, B.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Chai, Z.; Decowski, M. P.; García, E.; Gburek, T.; George, N. K.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Harrington, A. S.; Hauer, M.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lee, J. W.; Lin, W. T.; Manly, S.; McLeod, D.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Seals, H.; Sedykh, I.; Skulski, W.; Smith, C. E.; Stankiewicz, M. A.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tang, J.-L.; Tonjes, M. B.; Trzupek, A.; Vale, C. M.; van Nieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Wenger, E.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.; Zhang, J.; Phobos Collaboration

2005-08-01

This paper describes the conclusions that can be drawn from the data taken thus far with the PHOBOS detector at RHIC. In the most central Au + Au collisions at the highest beam energy, evidence is found for the formation of a very high energy density system whose description in terms of simple hadronic degrees of freedom is inappropriate. Furthermore, the constituents of this novel system are found to undergo a significant level of interaction. The properties of particle production at RHIC energies are shown to follow a number of simple scaling behaviors, some of which continue trends found at lower energies or in simpler systems. As a function of centrality, the total number of charged particles scales with the number of participating nucleons. When comparing Au + Au at different centralities, the dependence of the yield on the number of participants at higher p ( ˜4 GeV/c) is very similar to that at low transverse momentum. The measured values of charged particle pseudorapidity density and elliptic flow were found to be independent of energy over a broad range of pseudorapidities when effectively viewed in the rest frame of one of the colliding nuclei, a property we describe as "extended longitudinal scaling". Finally, the centrality and energy dependences of several observables were found to factorize to a surprising degree.

Optimal Integration of Cascade Thermoelectric Cooler into Electronic Housing: Experimental Approach

Science.gov (United States)

Semeniuk, V.; Protsenko, D.

2018-06-01

The problem of the optimal integration of thermoelectrically cooled optoelectronic components into an electronic housing is studied with the emphasis on practical implementation. The lines of 2-stage and 3-stage thermoelectric coolers (TECs) compatible with TO8 housing have been developed, and their parameters are measured in a wide range of heat sink temperatures. The TECs are optimized to receive a temperature difference of 100-110 K under a heat load from 70 mW to 100 mW with minimal power consumption. To fit into a standard housing interior, all the TECs have the same overall dimensions, regardless of the number of stages. Details of the TEC configurations and their performance characteristics are presented and discussed.

Development of a 400 kV 80 mA Cockcroft-Walton power supply and 12 kW isolation transformer systems for neutron generators

Science.gov (United States)

Lu, X.; Chen, S.; Zhang, Y.; Huang, Z.; Ma, Z.; Yao, Z.

2017-06-01

A 400 kV 80 mA Cockcroft-Walton power supply driven by 2.5 kHz frequency, and 12 kW isolation transformer systems are developed for an intense DD/DT neutron generator. The design, construction, and testing of the high voltage (HV) power supply and isolation transformer systems are detailed reported. The structure of step-up transformers can make the potential distribution uniform, and auxiliary coils of the isolation transformers can improve the power transmission efficiency significantly. The testing results show that the HV power supply can reach 400 kV, and the isolation transformer systems can withstand 400 kV voltages and its power transmission efficiency is about 98.1%.

Cryogenic cooler thermal coupler

International Nuclear Information System (INIS)

Green, K.E.; Talbourdet, J.A.

1984-01-01

A thermal coupler assembly mounted to the coldfinger of a cryogenic cooler which provides improved thermal transfer between the coldfinger and the detector assembly mounted on the dewar endwell. The thermal coupler design comprises a stud and spring-loaded cap mounted on the coldfinger assembly. Thermal transfer is made primarily through the air space between the cap and coldwell walls along the radial surfaces. The cap is spring loaded to provide thermal contact between the cap and endwell end surfaces

sPHENIX: The next generation heavy ion detector at RHIC

International Nuclear Information System (INIS)

Campbell, Sarah

2017-01-01

sPHENIX is a new collaboration and future detector project at Brookhaven National Laboratory’s Relativistic Heavy Ion Collider (RHIC). It seeks to answer fundamental questions on the nature of the quark gluon plasma (QGP), including its coupling strength and temperature dependence, by using a suite of precision jet and upsilon measurements that probe different length scales of the QGP. This is possible with a full acceptance, | η | < 1 and 0-2 π in φ , electromagentic and hadronic calorimeters and precision tracking enabled by a 1.5 T superconducting magnet. With the increased luminosity afforded by accelerator upgrades, sPHENIX is going to perform high statistics measurements extending the kinematic reach at RHIC to overlap the LHC’s. This overlap is going to facilitate a better understanding of the role of temperature, density and parton virtuality in QGP dynamics and, specifically, jet quenching. This paper focuses on key future measurements and the current state of the sPHENIX project. (paper)

Material Selection for Competition–A Case Study for Air Coolers

Directory of Open Access Journals (Sweden)

Luma A. H. Al Kindi

2018-02-01

Full Text Available Competition is one of the most important challenges that is facing the marketing of industrial products in today's markets. In this research study of the impact of material selection factor for air coolers of different materials is applied. Investigation on the air cooler windows which are part of the body of air coolers is conducted. Corrosion resistance, thermal conductivity, strength of material, weight, shape, cost and manufacturing process are the factors that are applied and calculated on three types of materials Aluminum, Galvanized steel and polypropylene. The physical properties of the three mentioned materials are used to calculate Merit Index .The corrosion average, according to Tafel Method depending the corrosion current and adopting contactors for the anodic and cathodic metals behaviors is performed. ANSYS is adopted using the three samples for the selected materials Aluminum, Galvanized steel and polypropylene to measure maximum stress and deflection are measured. Accordingly, the results are compared to choose the best alternative. It is observed that the polypropylene is the best choice depending three factors while the aluminum material is better depending two factors and the galvanized steel is regarded as the best in only one factor, the rest factors are identical when choosing  an alternative material for manufacturing the air cooler windows.

HIGH PT MEASUREMENT AT RHIC

International Nuclear Information System (INIS)

MIODUSZEWSKI, S.

2003-01-01

We present recent high transverse momentum measurements in Au+Au and p+p collisions at the Relativistic Heavy Ion Collider (RHIC). We define and show the nuclear modification factor for neutral pions and charged hadrons and discuss the particle species dependence. By means of the nuclear modification factor, we observe a suppression factor at high p T of 5-6 for neutral pions and 3-4 for charged hadrons in central Au+Au collisions relative to the binary-scaled yields in p+p (or peripheral) collisions. Finally we present strong evidence for the observation of jets in Au+Au collisions and the disappearance of the away-side jet in central Au+Au collisions

ABORT GAP CLEANING IN RHIC

International Nuclear Information System (INIS)

DREES, A.; AHRENS, L.; III FLILLER, R.; GASSNER, D.; MCINTYRE, G.T.; MICHNOFF, R.; TRBOJEVIC, D.

2002-01-01

During the RHIC Au-run in 2001 the 200 MHz storage cavity system was used for the first time. The rebucketing procedure caused significant beam debunching in addition to amplifying debunching due to other mechanisms. At the end of a four hour store, debunched beam could account for approximately 30%-40% of the total beam intensity. Some of it will be in the abort gap. In order to minimize the risk of magnet quenching due to uncontrolled beam losses at the time of a beam dump, a combination of a fast transverse kicker and copper collimators were used to clean the abort gap. This report gives an overview of the gap cleaning procedure and the achieved performance

Design and measured performance of a porous evaporative cooler for preservation of fruits and vegetables

International Nuclear Information System (INIS)

Anyanwu, E.E.

2004-01-01

The design, construction and measured performance of a porous evaporative cooler for preservation of fruits and vegetables are reported. The experimental cooler, with a total storage space of 0.014 m 3 , consists of a cuboid shaped porous clay container located inside another clay container. The gap between them is filled with coconut fibre. A water reservoir linked to the cooler at the top through a flexible pipe supplied water to fill the gap, thus keeping the coconut fibre continuously wet. Results of the transient performance tests revealed that the cooler storage chamber temperature depression from ambient air temperature varied over 0.1-12 deg. C. Ambient air temperatures during the test periods ranged over 22-38 deg. C. The results also illustrate superior performance of the cooler over open air preservation of vegetables soon after harvest during the diurnal operations. Thus, the evaporative cooler has prospects for use for short term preservation of vegetables and fruits soon after harvest

Calirimeter/absorber optimization for a RHIC dimuon experiment

Energy Technology Data Exchange (ETDEWEB)

Aronson, S.H.; Murtagh, M.J.; Starks, M. [Brookhaven National Lab., Upton, NY (United States); Liu, X.T.; Petitt, G.A.; Zhang, Z. [Georgia State Univ., Atlanta (United States); Ewell, L.A.; Hill, J.C.; Wohn, F.K. [Iowa State Univ., Ames (United States); Costales, J.B.; Namboodiri, M.N., Sangster, T.C.; Thomas, J.H. [Lawrence Livermore National Lab., CA (United States); Gavron, A.; Waters, L. [Los Alamos National Lab., NM (United States); Kehoe, W.L.; Steadman, S.G. [Massachusetts Institute of Technology, Cambridge (United States); Awes, T.C.; Obenshain, F.E.; Saini, S.; Young, G.R. [Oak Ridge National Lab., TN (United States); Chang, J.; Fung, S.Y.; Kang, J.H. [Univ. of California, Riverside, CA (United States); Kreke, J.; He, Xiaochun, Sorensen, S.P. [Univ. of Tennessee, Knoxville (United States); Cornell, E.C.; Maguire, C.F. [Vanderbilt Univ., Nashville, TN (United States)

1991-12-31

The RD-10 R&D effort on calorimeter/absorber optimization for a RHIC experiment had an extended run in 1991 using the A2 test beam at the AGS. Measurements were made of the leakage of particles behind various model hadron calorimeters. Behavior of the calorimeter/absorber as a muon-identifier was studied. First comparisons of results from test measurements to calculated results using the GHEISHA code were made

Parton-hadron cascade approach at SPS and RHIC

Energy Technology Data Exchange (ETDEWEB)

Nara, Yasushi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1998-07-01

A parton-hadron cascade model which is the extension of hadronic cascade model incorporating hard partonic scattering based on HIJING is presented to describe the space-time evolution of parton/hadron system produced by ultra-relativistic nuclear collisions. Hadron yield, baryon stopping and transverse momentum distribution are calculated and compared with HIJING and VNI. Baryon density, energy density and temperature for RHIC are calculated within this model. (author)

The effects of cross-link length on the thermal properties of epoxy-resins from 1.5 to 80 K

International Nuclear Information System (INIS)

Nicholls, C.I.; Rosenberg, H.M.

1981-01-01

The thermal conductivity and diffusivity of epoxy-resins with cross-links of varying lengths have been measured from 1.5 to 80 K. The longer the cross-links, the higher is the conductivity in the liquid helium range, but this behaviour is inverted at 80 K. The specific heat is not dependent on the length of the cross-links. The results are discussed in the light of current ideas on the thermal properties of glasses. (orig.)

MEMS Stirling Cooler Development Update

Science.gov (United States)

Moran, Matthew E.; Wesolek, Danielle

2003-01-01

This presentation provides an update on the effort to build and test a prototype unit of the patented MEMS Stirling cooler concept. A micro-scale regenerator has been fabricated by Polar Thermal Technologies and is currently being integrated into a Stirling cycle simulator at Johns Hopkins University Applied Physics Laboratory. A discussion of the analysis, design, assembly, and test plans for the prototype will be presented.

Cooler Storage Ring at China Institute of Modern Physics

CERN Document Server

Wen-Xia, Jia; Zhan, W

2005-01-01

CSR, a new ion cooler-storage-ring project in China IMP, is a double ring system, and consists of a main ring (CSRm) and an experimental ring (CSRe). The two existing cyclotrons SFC (K=69) and SSC (K=450) of the Heavy Ion Research Facility in Lanzhou (HIRFL) will be used as its injector system. The heavy ion beams with the energy range of 7-30 MeV/nucleus from the HIRFL will be accumulated, cooled and accelerated to the higher energy range of 100-500 MeV/ nucleus in CSRm, and then extracted fast to produce radioactive ion beams or highly charged heavy ions. Those secondary beams will be accepted and stored or decelerated by CSRe for many internal-target experiments or high precision spectroscopy with beam cooling. On the other hand, the beams with the energy range of 100-1000MeV/ nucleus will also be extracted from CSRm by using slow extraction or fast extraction for many external-target experiments. CSR project was started in the end of 1999 and will be finished in 2006. In this paper the outline and the act...

Cerebral bone subtraction CT angiography using 80 kVp and sinogram-affirmed iterative reconstruction: contrast medium and radiation dose reduction with improvement of image quality

Energy Technology Data Exchange (ETDEWEB)

Nagayama, Yasunori [Kumamoto City Hospital, Department of Radiology, Kumamoto (Japan); Kumamoto University, Department of Diagnostic Radiology, Chuo-ku, Kumamoto (Japan); Nakaura, Takeshi; Oda, Seitaro; Kidoh, Masafumi; Utsunomiya, Daisuke; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Chuo-ku, Kumamoto (Japan); Tsuji, Akinori; Urata, Joji; Furusawa, Mitsuhiro; Yuki, Hideaki; Hirarta, Kenichiro [Kumamoto City Hospital, Department of Radiology, Kumamoto (Japan)

2017-02-15

The purpose of this study was to evaluate the feasibility of a contrast medium (CM), radiation dose reduction protocol for cerebral bone-subtraction CT angiography (BSCTA) using 80-kVp and sinogram-affirmed iterative reconstruction (SAFIRE). Seventy-five patients who had undergone BSCTA under the 120- (n = 37) or the 80-kVp protocol (n = 38) were included. CM was 370 mgI/kg for the 120-kVp and 296 mgI/kg for the 80-kVp protocol; the 120- and the 80-kVp images were reconstructed with filtered back-projection (FBP) and SAFIRE, respectively. We compared effective dose (ED), CT attenuation, image noise, and contrast-to-noise ratio (CNR) of two protocols. We also scored arterial contrast, sharpness, depiction of small arteries, visibility near skull base/clip, and overall image quality on a four-point scale. ED was 62% lower at 80- than 120-kVp (0.59 ± 0.06 vs 1.56 ± 0.13 mSv, p < 0.01). CT attenuation of the internal carotid artery (ICA) and middle cerebral artery (MCA) was significantly higher on 80- than 120-kVp (ICA: 557.4 ± 105.7 vs 370.0 ± 59.3 Hounsfield units (HU), p < 0.01; MCA: 551.9 ± 107.9 vs 364.6 ± 62.2 HU, p < 0.01). The CNR was also significantly higher on 80- than 120-kVp (ICA: 46.2 ± 10.2 vs 36.9 ± 7.6, p < 0.01; MCA: 45.7 ± 10.0 vs 35.7 ± 9.0, p < 0.01). Visibility near skull base and clip was not significantly different (p = 0.45). The other subjective scores were higher with the 80- than the 120-kVp protocol (p < 0.05). The 80-kVp acquisition with SAFIRE yields better image quality for BSCTA and substantial reduction in the radiation and CM dose compared to the 120-kVp with FBP protocol. (orig.)

Some calculations for the RHIC kicker

International Nuclear Information System (INIS)

Claus, J.

1996-12-01

This paper starts with a brief discussion of the design of the RHIC injection kicker magnets which calls for longitudinal and capacitive sections of the same order as the aperture, not much larger nor much smaller. This makes accurate analytical prediction of their behavior very difficult. In order to gain at least some qualitative insight of that behavior, the author preformed calculations which are based on the actual dimensions of the kickers but which neglect the end effects of the individual sections. The effects of the sectionalization are therefore exaggerated relative to reality in the results

Electronics for the RHIC PHENIX detector

International Nuclear Information System (INIS)

Young, G.R.

1992-01-01

The PHENIX detector for RHIC is being designed to measure lepton pairs, direct photons and hadrons emitted in collisions of heavy nuclei at center of mass energies up to 200 GeV/(nucleon-pair). The physics goal is tests of predictions concerning the existence and nature of a deconfined state of strongly-interacting matter. The relatively large final state multiplicities, which reach 1500 charged particles per unit of rapidity, place strong demands on detector segmentation and control of electronics cost and power consumption. An overview of present ideas concerning signal processing and data rates for PHENIX will be presented

Recent Results from PHOBOS at Rhic

Science.gov (United States)

Garcia, Edmundo; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Busza, W.; Carroll, A.; Chai, Z.; Decowski, M. P.; Garcia, E.; Gburek, T.; George, N.; Gulbrandsen, K.; Halliwell, C.; Hamblen, J.; Hauer, M.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Khan, N.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Reed, C.; Roland, C.; Roland, G.; Sagerer, J.; Seals, H.; Sedykh, I.; Smith, C. E.; Stankiewicz, M. A.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tonjes, M. B.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Wenger, E.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wysłouch, B.

The PHOBOS detector is one of four heavy-ion experiments at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. In this paper we will review some of the results of PHOBOS from the data collected in p+p, d+Au and Au+Au collisions at nucleon-nucleon center-of-mass energies up to 200 GeV. In the most central Au+Au collisions at the highest energy, evidence is found for the formation of a very high energy density and highly interactive system, which can not be described in terms of hadrons, and which has a relatively low baryon density.

The making of automation air fiddling unit (AHU) for G 71 cooler system

International Nuclear Information System (INIS)

Suripto

2003-01-01

A design of the making automation of air handling unit (AHU) for G. 71 cooler system at the design it has been conducted AHU operational time programming for G. 71 cooler system, when applied if will operate as programmed. flopefully, it mill save electric power and the dependency to the operator can be reduced significantly therefore it will increase efficiency and optimization in the usage of the cooler system. At the and if will reduce and save operational cost mainly in maintenance cost

Vacuum packaging of InGaAs focal plane array with four-stage thermoelectric cooler

Science.gov (United States)

Mo, De-feng; Liu, Da-fu; Yang, Li-yi; Xu, Qin-fei; Li, Xue

2013-09-01

The InGaAs focal plane array (FPA) detectors, covering the near-infrared 1~2.4 μm wavelength range, have been developed for application in space-based spectroscopy of the Earth atmosphere. This paper shows an all-metal vacuum package design for area array InGaAs detector of 1024×64 pixels, and its architecture will be given. Four-stage thermoelectric cooler (TEC) is used to cool down the FPA chip. To acquire high heat dissipation for TEC's Joule-heat, tungsten copper (CuW80) and kovar (4J29) is used as motherboard and cavity material respectively which joined by brazing. The heat loss including conduction, convection and radiation is analyzed. Finite element model is established to analyze the temperature uniformity of the chip substrate which is made of aluminum nitride (AlN). The performance of The TEC with and without heat load in vacuum condition is tested. The results show that the heat load has little influence to current-voltage relationship of TEC. The temperature difference (ΔT) increases as the input current increases. A linear relationship exists between heat load and ΔT of the TEC. Theoretical analysis and calculation show that the heat loss of radiation and conduction is about 187 mW and 82 mW respectively. Considering the Joule-heat of readout circuit and the heat loss of radiation and conduction, the FPA for a 220 K operation at room temperature can be achieved. As the thickness of AlN chip substrate is thicker than 1 millimeter, the temperature difference can be less than 0.3 K.

Strange and heavy hadrons production from coalescence plus fragmentation in AA collisions at RHIC and LHC

Science.gov (United States)

Plumari, Salvatore; Minissale, Vincenzo; Das, Santosh K.; Scardina, Francesco; Greco, Vincenzo

2018-02-01

In a coalescence plus fragmentation approach we study the pT spectra of charmed hadrons D0, Ds up to about 10 GeV and the Λ+c /D0 ratio from RHIC to LHC energies. In this study we have included the contribution from decays of heavy hadron resonances and also that due to fragmentation of heavy quarks that are left in the system after coalescence. The pT dependence of the heavy baryon/meson ratios is found to be sensitive to the heavy quark mass. In particular we found that the Λc/D0 is much flatter than the one for light baryon/meson ratio like p/π and Λ/K.

Strangeness production in heavy ion collisions: What have we learned with the energy increase from SPS to RHIC

International Nuclear Information System (INIS)

Odyniec, Grazyna

2002-01-01

A review of strange particle production in heavy ion collisions at ultrarelativistic energies is presented. The particle yields and ratios from SPS and RHIC are discussed in view of the newest developments in understanding collision dynamics, and in view of their role in the search for a quark gluon plasma. A strangeness enhancement, most notably observed in CERN Pb-beam results, shows a remarkable two fold global enhancement with a much larger effect seen in the case of multistrange baryons. Hadronic models did fail to explain this pattern. At RHIC energy strangeness assumes a different role, since temperatures are higher and the central rapidity region almost baryon-free. An intriguing question: ''Did RHIC change the way we understand strangeness production in heavy ion collisions ?'' is discussed

Thermal transport properties of niobium and some niobium base alloys from 80 to 16000K

International Nuclear Information System (INIS)

Moore, J.P.; Graves, R.S.; Williams, R.K.

1980-01-01

The electrical resistivities and absolute Seebeck coefficients of 99.8 at. % niobium with a RRR of 36, Nb-4.8 at. % W, Nb-5 at. % Mo, Nb-10 at. % Mo, and Nb-2.4 at. % Mo-2.4 at. % Zr were measured from 80 to 1600 0 K, and the thermal conductivities of the niobium and Nb-5 at. % W were measured from 80 to 1300 0 K. A technique is described for measuring the electrical resistivity and Seebeck coefficient of a specimen during radial heat flow measurements of the thermal conductivity. The transport property results, which had uncertainties of +-0.4%for electrical resistivity and +-1.4% for thermal conductivity, showed the influence of tungsten and molybdenum solutes on the transport properties of niobium and were used to obtain the electronic Lorenz function of pure niobium, which was found to approach the Sommerfeld value at high temperatures

CFD study of a simple orifice pulse tube cooler

Science.gov (United States)

Zhang, X. B.; Qiu, L. M.; Gan, Z. H.; He, Y. L.

2007-05-01

Pulse tube cooler (PTC) has the advantages of long-life and low vibration over the conventional cryocoolers, such as G-M and Stirling coolers because of the absence of moving parts in low temperature. This paper performs a two-dimensional axis-symmetric computational fluid dynamic (CFD) simulation of a GM-type simple orifice PTC (OPTC). The detailed modeling process and the general results such as the phase difference between velocity and pressure at cold end, the temperature profiles along the wall as well as the temperature oscillations at cold end with different heat loads are presented. Emphases are put on analyzing the complicated phenomena of multi-dimensional flow and heat transfer in the pulse tube under conditions of oscillating pressure. Swirling flow pattern in the pulse tube is observed and the mechanism of formation is analyzed in details, which is further validated by modeling a basic PTC. The swirl causes undesirable mixing in the thermally stratified fluid and is partially responsible for the poor overall performance of the cooler, such as unsteady cold-end temperature.

Modeling of Hydrate Formation Mode in Raw Natural Gas Air Coolers

Science.gov (United States)

Scherbinin, S. V.; Prakhova, M. Yu; Krasnov, A. N.; Khoroshavina, E. A.

2018-05-01

Air cooling units (ACU) are used at all the gas fields for cooling natural gas after compressing. When using ACUs on raw (wet) gas in a low temperature condition, there is a danger of hydrate plug formation in the heat exchanging tubes of the ACU. To predict possible hydrate formation, a mathematical model of the air cooler thermal behavior used in the control system shall adequately calculate not only gas temperature at the cooler's outlet, but also a dew point value, a temperature at which condensation, as well as the gas hydrate formation point, onsets. This paper proposes a mathematical model allowing one to determine the pressure in the air cooler which makes hydrate formation for a given gas composition possible.

Highlights from PHENIX transverse spin program at RHIC

International Nuclear Information System (INIS)

Liu, M.

2013-01-01

In recent years, there has been exciting development in both experimental and theoretical studies of transverse spin phenomena in high energy polarized p+p and polarized DIS collisions. In the p+p frontier, the polarized p+p collider at RHIC provides a unique opportunity to investigate the novel physics that causes the large spin effects seen in the transversely polarized p+p collisions over the past 30 years, particularly in the forward rapidity. Since the beginning, PHENIX has been conducting a very active transverse spin physics program to study Sivers, Collins and other novel spin effects at RHIC, including measurements of transverse single spin asymmetry (TSSA) in light and heavy quark productions, leading neutron TSSA in the very forward rapidity, and di-hadron (and 'jet') spin correlations in a wide kinematics range, just to name a few. In 2012, PHENIX collected transversely polarized 200 GeV p+p data with a record high luminosity of 9.24 pb −1 , with an average beam polarization of 58%. In this talk, I highlight the recent results from the PHENIX experiment, and also briefly discuss the near-term prospects of new transverse spin measurements only possible with the latest (forward) silicon vertex detectors, (F)VTX, and the upcoming forward MPC-EX upgrade detectors.

Micro-coolers fabricated as a component in an integrated circuit

International Nuclear Information System (INIS)

Glover, James; Oxley, Chris H; Khalid, Ata; Cumming, David; Stephen, Alex; Dunn, Geoff

2015-01-01

The packing density and power capacity of integrated electronics is increasing resulting in higher thermal flux densities. Improved thermal management techniques are required and one approach is to include thermoelectric coolers as part of the integrated circuit. An analysis will be described showing that the supporting substrate will have a large influence on the cooling capacity of the thermoelectric cooler. In particular, for materials with a low ZT figure of merit (for example gallium arsenide (GaAs) based compounds) the substrate will have to be substantially thinned to obtain cooling, which may preclude the use of thermoelectric coolers, for example, as part of a GaAs based integrated circuit. Further, using experimental techniques to measure only the small positive cooling temperature difference (ΔT) between the anode (T h ) and the cathode (T c ) contacts can be misinterpreted as cooling when in fact it is heating. (paper)

"Upgraded" physics at the LHC and RHIC

Energy Technology Data Exchange (ETDEWEB)

Llope, W. J. [Wayne State University, Detroit, MI (United States)

2017-09-03

Closeout materials enclosed. This grant supported a postdoctoral scientist (S. Jowzaee) and the tuition for a graduate student (B. Erko), both working under the supervision of Prof. W.J. Llope at Wayne State University. Travel to a STAR Collaboration Meeting and the Quark Matter 2017 conference was also supported. The physics research concentrated on particle-identified two-particle correlations in the Beam Energy Scan data from the STAR experiment at RHIC. S. Jowzaee gave an oral presentation on this research at the Quark Matter 2017 conference.

Initial operation of cooler ring, TARN II

International Nuclear Information System (INIS)

Katayama, T.; Chida, K.; Honma, T.

1989-01-01

TARN II is a heavy ion cooler synchrotron for the studies of accelerator, atomic and nuclear physics, presently being constructed at the Institute for Nuclear Study, University of Tokyo. Its maximum energy is 370 MeV/u for the ions of a charge to mass ratio of q/A = 0.5, corresponding to a magnetic rigidity of 6.1 T·m. The circumference is 77.76 m, just 17 times the extraction orbit of injector cyclotron. Six long straight sections, 4.20 m in length each, are used for the beam injection, extraction, electron cooler and RF accelerating cavity, respectively. At the beginning of 1989, the first experiment of beam injection has been performed successfully with use of 28 MeV α particles. In this paper, the status and initial results of operation of TARN II are presented. (author)

Development of a microminiature sorption cooler

NARCIS (Netherlands)

Burger, Johannes; Holland, Harry; ter Brake, Marcel; Rogalla, Horst; Wade, Larry

1997-01-01

The development of a microcooler for operations below 80 K, for low temperature electronic devices requiring small cooling powers of the order of 10 mW is described. A sorption compressor combined with Joule-Thomson (JT) expansion was selected for miniaturization. The advantage of the system is

The mobility of Li+ and K+ ions in helium and argon at 294 and 80 K and derived interaction potentials

International Nuclear Information System (INIS)

Cassidy, R.A.; Elford, M.T.

1983-01-01

The analysis of mobility data is a valuable technique for deriving ion-atom interaction potentials or testing at initio potentials particularly at relatively large internuclear separations. In order to obtain the most complete information on the long range part of the potential it is necessary to have mobility data at sufficiently low gas temperatures and small values of E/N that the mobility is determined only by the dipole polarization force. Although this condition can be reasonably well met at room temperature for gases of high polarizability, this is not the case for ions in helium and in particular for the most well studied case, that of Li + in helium. The prime purpose of the present measurements was to obtain low temperature data for Li + in helium in order to determine more accurately the attractive long range tail of the potential. The measurements were also extended to argon to demonstrate the effect of the polarizability on the derivation of potentials. The mobility measurements were made using a drift tube-mass spectrometer system employing the Bradbury-Nielsen time of flight technique. Measurements were performed at 294 K and 80 K. The 'three temperature' theory of Lin, Viehland and Mason was used to fit interaction potentials to the present data. Detailed comparisons are made here only for the case of Li + ions in helium. The new data for 80 K provide additional information on the potential at internuclear separations which cover the range to 5 A. (Authors)

Photoproduction at collider energies: from RHIC and HERA to the LHC

CERN Document Server

Baltz, A; Brodsky, S J; D'Enterria, D G; Dreyer, U; Engel, R; Frankfurt, L; Gorbunov, Y; Guzey, V; Hamilton, A; Klasen, M; Klein, S R; Kowalski, H; Levonian, S; Lourenço, C; Machado, M V T; Nachtmann, O; Nagy, Z; Nystrand, J; Piotrzkowski, K; Ramalhete, P; Savin, A; Scapparone, E; Schicker, R; Silvermyr, D; Strikman, M I; Valkárová, A; Vogt, R; Yilmaz, M; Enterria, David d'

2007-01-01

We present the mini-proceedings of the workshop on "Photoproduction at collider energies: from RHIC and HERA to the LHC" held at the European Centre for Theoretical Studies in Nuclear Physics and Related Areas (ECT*, Trento) from January 15 to 19, 2007. The workshop gathered both theorists and experimentalists to discuss the current status of investigations of high-energy photon-induced processes at different colliders (HERA, RHIC, and Tevatron) as well as preparations for extension of these studies at the LHC. The main physics topics covered were: (i) small-$x$ QCD in photoproduction studies with protons and in electromagnetic (aka. ultraperipheral) nucleus-nucleus collisions, (ii) hard diffraction physics at hadron colliders, and (iii) photon-photon collisions at very high energies: electroweak and beyond the Standard Model processes. These mini-proceedings consist of an introduction and short summaries of the talks presented at the meeting.

Modeling of a regenerative indirect evaporative cooler for a desiccant cooling system

DEFF Research Database (Denmark)

Bellemo, Lorenzo; Elmegaard, Brian; Reinholdt, Lars O.

This paper presents a numerical study of a regenerative indirect evaporative cooler, the so-called Dew Point Cooler (DPC), which is part of a Desiccant Cooling system that may both dehumidify and cool humid air. The DPC model is based on first principles using a 1D finite volume scheme...

Binary and ternary recombination of D3+ ions at 80-130 K: Application of laser absorption spectroscopy

Science.gov (United States)

Dohnal, Petr; Hejduk, Michal; Rubovič, Peter; Varju, Jozef; Roučka, Štěpán; Plašil, Radek; Glosík, Juraj

2012-11-01

Recombination of D_3^+ ions with electrons at low temperatures (80-130 K) was studied using spectroscopic determination of D_3^+ ions density in afterglow plasmas. The use of cavity ring-down absorption spectroscopy enabled an in situ determination of the abundances of the ions in plasma and the translational and the rotational temperatures of the recombining ions. Two near infrared transitions at (5792.70 ± 0.01) cm-1 and at (5793.90 ± 0.01) cm-1 were used to probe the number densities of the lowest ortho state and of one higher lying rotational state of the vibrational ground state of D_3^+ ion. The results show that D_3^+ recombination with electrons consists of the binary and the third-body (helium) assisted process. The obtained binary recombination rate coefficients are in agreement with a recent theoretical prediction for electron-ion plasma in thermodynamic equilibrium with αbin(80 K) = (9.2 ± 2.0) × 10-8 cm3 s-1. The measured helium assisted ternary rate coefficients KHe are in agreement with our previously measured flowing afterglow data giving a value of KHe(80 K) = (1.2 ± 0.3) × 10-25 cm6 s-1.

Current status of PHOBOS at sign RHIC

International Nuclear Information System (INIS)

Betts, R.R.; Univ. of Illinois, Chicago, IL

1996-01-01

Four experiments are currently approved for the first measurements with colliding heavy ion beams from the Relativistic Heavy Ion Collider (RHIC) which is scheduled to come into operation in Spring 1999. These experiments are named STAR, Phoenix, PHOBOS and Brahms. It is expected that central collisions of 100 GeV/u Au + Au at RHIC will lead to energy densities far above any so far attained in the laboratory and it is suspected and hoped that this situation will lead to qualitatively new physics perhaps associated with the creation of a large volume containing a plasma of deconfined quarks and gluons. All four experiments attempt to search for signatures of new physics through combinations of measurements of quantities such as the multiplicity of produced particles, the average transverse momentum of these particles, fluctuations in their multiplicity distribution, their flavor composition, the size scales of the volume from which they are emitted, mass shifts and changes in the decay widths of resonances which decay inside the high energy density volume etc. The PHOBOS detector addresses these issues with a Multiplicity Array which covers the pseudo-rapidity region -5.3 ≤ η ≤ 5.3 with a coverage of 85% of 4π and also incorporates a Vertex Detector. The Multiplicity Array is complemented by two Multi-Particle Spectrometers, each of which cover the range 0.5 ≤ η ≤ 1.5 and azimuthal angle range Δφ = 11 degree. Various trigger and monitor detectors complete PHOBOS

Industrial production of RHIC magnets

International Nuclear Information System (INIS)

Anerella, M.D.; Fisher, D.H.; Sheedy, E.; McGuire, T.

1996-01-01

RHIC 8 cm aperture dipole magnets and quadrupole cold masses are being built for Brookhaven National Laboratory (BNL) by Northrop Grumman Corporation at a production rate of one dipole magnet and two quadrupole cold masses per day. This work was preceded by a lengthy Technology Transfer effort which is described elsewhere. This paper describes the tooling which is being used for the construction effort, the production operations at each workstation, and also the use of trend plots of critical construction parameters as a tool for monitoring performance in production. A report on the improvements to production labor since the start of the programs is also provided. The magnet and cold mass designs, and magnetic test results are described in more detail in a separate paper

RAPIDE 0.0 RHIC Accelerator Physics Intrepid Development Environment

Energy Technology Data Exchange (ETDEWEB)

Satogata, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Saltmarsh, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Peggs, S. [Brookhaven National Lab. (BNL), Upton, NY (United States)

1993-08-01

This document is a guide to the common environmental features of computing in (and around) the RHIC Accelerator Physics.sectio on the 'zoo' cluster of UNJX workstations, in RAPIDE, the RHIC Accelerator Physics Intrepid Development Environment It is hoped tliat later revisions of this document will approach a more professional 'style guide', beyond the convenient collection of pointers and hints presented here. RAP does two kinds of computing, "controls" and "general", addressed in sections 2 and 3 of this document For general computing, efficient system administration requires cooperation in using a common environment There is a much stronger need to define - and adhere to - a commonly agreed set of styles (or rules) in developing controls software. Right now, these rules have been set "de facto". Future improvements to the controls environment, particularly in response to the opinions of users, depends on broad knowledge of what the rules are. There are environmental issues that are basic to both controls and general computing, and that are so fundamental that they are (almost) unarguable. They are described immediately below, in the next section.

The strongly coupled quark-gluon plasma created at RHIC

International Nuclear Information System (INIS)

Heinz, Ulrich

2009-01-01

The relativistic heavy-ion collider (RHIC) was built to re-create and study in the laboratory the extremely hot and dense matter that filled our entire universe during its first few microseconds. Its operation since June 2000 has been extremely successful, and the four large RHIC experiments have produced an impressive body of data which indeed provide compelling evidence for the formation of thermally equilibrated matter at unprecedented temperatures and energy densities-a 'quark-gluon plasma (QGP)'. A surprise has been the discovery that this plasma behaves like an almost perfect fluid, with extremely low viscosity. Theorists had expected a weakly interacting gas of quarks and gluons, but instead we seem to have created a strongly coupled plasma liquid. The experimental evidence strongly relies on a feature called 'elliptic flow' in off-central collisions, with additional support from other observations. This paper explains how we probe the strongly coupled QGP, describes the ideas and measurements which led to the conclusion that the QGP is an almost perfect liquid, and shows how they tie relativistic heavy-ion physics into other burgeoning fields of modern physics, such as strongly coupled Coulomb plasmas, ultracold systems of trapped atoms and superstring theory

Polarization response of RHIC electron lens lattices

Directory of Open Access Journals (Sweden)

V. H. Ranjbar

2016-10-01

Full Text Available Depolarization response for a system of two orthogonal snakes at irrational tunes is studied in depth using lattice independent spin integration. In particular we consider the effect of overlapping spin resonances in this system, to understand the impact of phase, tune, relative location and threshold strengths of the spin resonances. These results are benchmarked and compared to two dimensional direct tracking results for the RHIC e-lens lattice and the standard lattice. Finally we consider the effect of longitudinal motion via chromatic scans using direct six dimensional lattice tracking.

Heavy flavour production at RHIC and LHC

Directory of Open Access Journals (Sweden)

Innocenti Gian Michele

2018-01-01

Full Text Available In this proceedings, I present selected experimental results on heavy-flavour production at RHIC and at the LHC, which were presented at the Strangeness in Quark Matter 2017 conference. I will present a brief introduction to the heavy-flavour physics in heavy ion collisions and I will focus on recents measurements of in-medium energy loss and and collective properties of heavy-flavour particles, which provided important information on the mechanisms of heavy flavour interaction with the hot and dense medium created in ultra-relativistic heavy-ion collisions.

Polarization response of RHIC electron lens lattices

International Nuclear Information System (INIS)

Ranjbar, V. H.; Méot, F.; Bai, M.; Abell, D. T.; Meiser, D.

2016-01-01

Depolarization response for a system of two orthogonal snakes at irrational tunes is studied in depth using lattice independent spin integration. Particularly, we consider the effect of overlapping spin resonances in this system, to understand the impact of phase, tune, relative location and threshold strengths of the spin resonances. Furthermore, these results are benchmarked and compared to two dimensional direct tracking results for the RHIC e-lens lattice and the standard lattice. We then consider the effect of longitudinal motion via chromatic scans using direct six dimensional lattice tracking.

Tipe Dry Cell dan Wet Cell berdimensi 80 x 80 mm dengan Penambahan PWM E-3 FF (1 kHz

Directory of Open Access Journals (Sweden)

Yanur Arzaqa Ghiffari

2013-09-01

Full Text Available Ketersediaan bahan bakar minyak semakin terbatas dan hasil pembakarannya berdampak pada pencemaran lingkungan, salah satu solusinya dengan memanfaatkan gas HHO pada kendaraan bermotor. Penelitian dengan sistem direct connection, temperatur mencapai lebih dari 90oC menyebabkan  generator HHO menjadi rusak dan meleleh, maka penelitian ini menambahan alat untuk mengkontrol besarnya arus, frekuensi, dan duty cycle. Pengembangan generator HHO menggunakan tipe kering (dry cell dan tipe basah (wet cell dengan penambahan PWM (Pulse Width Modulation E-3 Fixed Frequency 1 kHz divariasikan berupa duty cycle: 20%, 40%, 60%, 80%  dan direct connection. Pengujian dilakukan di Laboratorium Teknik Pembakaran dan Bahan Bakar - Teknik Mesin ITS.  Dari hasil penelitian didapatkan karakteristik unjuk kerja terbaik pada kedua tipe generator HHO dengan penambahan PWM. Nilai arus dan tegangan lebih stabil dibandingkan dengan tanpa penambahan PWM (direct connection, namun arus cenderung meningkat seiring dengan kenaikan temperatur mencapai 70oC. Efisiensi terbaik pada generator tipe wet dengan duty cycle 80%,  yaitu 27,7 %.

Proceedings of RIKEN BNL Resarch Center Workshop: Fluctuations, Correlations and RHIC Low Energy Runs

Energy Technology Data Exchange (ETDEWEB)

Karsch, F.; Kojo, T.; Mukherjee, S.; Stephanov, M.; Xu, N.

2011-10-27

Most of our visible universe is made up of hadronic matter. Quantum Chromodynamics (QCD) is the theory of strong interaction that describes the hadronic matter. However, QCD predicts that at high enough temperatures and/or densities ordinary hadronic matter ceases to exist and a new form of matter is created, the so-called Quark Gluon Plasma (QGP). Non-perturbative lattice QCD simulations shows that for high temperature and small densities the transition from the hadronic to the QCD matter is not an actual phase transition, rather it takes place via a rapid crossover. On the other hand, it is generally believed that at zero temperature and high densities such a transition is an actual first order phase transition. Thus, in the temperature-density phase diagram of QCD, the first order phase transition line emanating from the zero temperature high density region ends at some higher temperature where the transition becomes a crossover. The point at which the first order transition line turns into a crossover is a second order phase transition point belonging to three dimensional Ising universality class. This point is known as the QCD Critical End Point (CEP). For the last couple of years the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory has been performing experiments at lower energies in search of the elusive QCD CEP. In general critical behaviors are manifested through appearance of long range correlations and increasing fluctuations associated with the presence of mass-less modes in the vicinity of a second order phase transition. Experimental signatures of the CEP are likely to be found in observables related to fluctuations and correlations. Thus, one of the major focuses of the RHIC low energy scan program is to measure various experimental observables connected to fluctuations and correlations. On the other hand, with the start of the RHIC low energy scan program, a flurry of activities are taking place to provide solid theoretical

Split-Stirling Cryogenic Refrigerators For Detector Cooling

Science.gov (United States)

Lehrfeld, Daniel

1983-08-01

Unfortunately, for user and manufacturer both, the closed-cycle cryogenic cooler to date has deserved its reputation as the "weak-link" in IR systems. When the cooler requires service at intervals of a few hundred hours at best, the quality of the system it serves is unfairly diminished. This paper addresses technological advances in the art of Stirling-cycle coolers which will increasingly cause that image of military cryocoolers to change for the better. A family of split-cycle coolers designed for long MTBF and in the final stages of development is the focus of the discussion. Their technological evolution, from multi-year-MTBF satellite system Stirling coolers developed in the U.S., and the UA 7011 cooler (tne first all-linear, military, production cooler) developed in Holland, is explained. Three new machines are discussed. Both 1/4 watt and 1 watt (nominal capacity) at 80°K linear-resonant, free-dispLacer Stirling coolers designed for thousands of hours of service-free operation are examined. The third machine is an advanced 1/4 watt at 80°K Stirling cooler incorporating the same component improvements in its free-displacer while utilizing a crankshaft-driven compressor. All three are designed to be compatible with standard U.S. 60 element and 120/180 element detector/dewars. The technologies of linear-resonant compressor and free-displacer expanders as embodied in these machines is discussed in sufficient detail that the reasons for their superior performance will he clear.

Experimental investigation of a portable desalination unit configured by a thermoelectric cooler

International Nuclear Information System (INIS)

Yıldırım, Cihan; Soylu, Sezgi Koçak; Atmaca, İbrahim; Solmuş, İsmail

2014-01-01

Highlights: • Portable humidification–dehumidification desalination system configured by a thermoelectric cooler is experimentally studied. • Effect of feed water mass flow rate and air flow velocity on COP value of TEC and system productivity are investigated. • Maximum daily yield of system and COP value of TEC unit were recorded as 143.6 g and 0.78, respectively. - Abstract: Possible use of a novel portable desalination system was investigated experimentally. The system is based on humidification–dehumidification principle and thermoelectric cooling technique. A thermoelectric cooler was integrated into the system to enhance the process of both humidification and dehumidification. A prototype was fabricated and its performance was tested for various working conditions of the prototype to observe complex relation between psychrometric and thermoelectric phenomena. The effect of feed water mass flow rate and air flow velocity on the COP value of the thermoelectric cooler and clean water production of the system were examined. The maximum daily yield of the system and the COP value of the thermoelectric cooler unit were recorded as 143.6 g and 0.78, respectively

Heavy ion program at BNL: AGS, RHIC [Relativistic Heavy Ion Collider

International Nuclear Information System (INIS)

Barton, D.S.

1987-01-01

With the recent commissioning of fixed target, heavy ion physics at the AGS, Brookhaven National Laboratory (BNL) has embarked on a long range program in support of relativistic heavy ion research. Acceleration of low mass heavy ions (up to sulfur) to an energy of about 14.5 GeV/nucleon is possible with the direct connection of the BNL Tandem Van de Graaff and AGS accelerators. When completed, the new booster accelerator will provide heavy ions over the full mass range for injection and subsequent acceleration in the AGS. BNL is now engaged in an active R and D program directed toward the proposed Relativistic Heavy Ion Collider (RHIC). The results of the first operation of the low mass heavy ion program will be reviewed, and future expectations discussed. The expected performance for the heavy ion operation of the booster will be described and finally, the current status and outlook for the RHIC facility will be presented

Improvement of cooldown time of LSF9599 flexure-bearing SADA cooler

Science.gov (United States)

Mullié, Jeroen; vd Groep, Willem; Bruins, Peter; Benschop, Tonny; de Koning, Arjan; Dam, Jacques

2006-05-01

Thales Cryogenics has presented the LSF 9599 SADA II flexure cooler in 2005. Based on Thales' well-known moving magnet flexure technology, the LSF 9599 complies with the SADA II specification with respect to performance, envelope and mass. Being the first manufacturer offering a full flexure-bearing supported cooler that fits within the SADA II envelope, Thales Cryogenics has been selected in several new (military) programs with their LSF coolers. For many of these new programs, the cooldown time requirements are more stringent than in the past, whereas at the same time size, complexity and thus thermal mass of the infrared sensor tends to increase. In order to respond to the need created by the combination of these trends, Thales Cryogenics started a development program to optimize cryogenic performance of the LSF 9599 cooler. The main goal for the development program is to reduce the cooldown time, while maintaining the SADA II compatible interface, and maintaining the robustness and proven reliability of the cooler. Within these constraints, the regenerator was further optimized using among others the experience with mixed-gauze regenerators obtained from our pulse tube research. Using the mixed gauze approach, the heat storage capacity of the regenerator is adapted as a function of the temperature profile over the regenerator, thus giving the optimum balance between heat storage capacity and pressure drop. A novel way of constructing the regenerator further decreases shuttle heat losses and other thermal losses in the regenerator. This paper describes the first results of the trade-offs and gives an overview of impact on cooldown times and efficiency figures achieved after the regenerator and displacer optimization.

Electromagnetic compatibility characterization of a BAe Stirling-cycle cryocooler for space application

Science.gov (United States)

Johnson, Dean L.; Ross, Ronald G., Jr.

1991-01-01

This paper describes the electromagnetic compatibility (EMC) measurements of an 80-K Stirling-cycle cooler. The measurements, performed in the JPL EMC test facility, include dc magnetic field characterization, radiated magnetic and electric field emissions, and conducted emissions on the internal lines between the cooler electronics and the cooler. The measurements conform to both the MILSTD-461C specifications as well as to the specifications for the NASA Earth Observing System.

POSSIBLE ORIGIN OF RHIC R OUT/R SID HBT RESULTS

International Nuclear Information System (INIS)

PADULA, S.S.

2002-01-01

The effects of opacity of the nuclei together with a blackbody type of emission along the system history are considered as a means to explain the ratio R out /R sid observed by STAR and PHENIX collaborations at RHIC. Within our model, no flow is required to explain the data trend of this ratio for large surface emissivities

POSSIBLE ORIGIN OF RHIC R OUT / R SID HBT RESULTS

International Nuclear Information System (INIS)

PADULA, S.

2002-01-01

The effects of opacity of the nuclei together with a blackbody type of emission along the system history are considered as a means to explain the ratio R out /R sid observed by STAR and PHENIX collaborations at RHIC. Within our model, no flow is required to explain the data trend of this ratio for large surface emissivities

Reliability improvements on Thales RM2 rotary Stirling coolers: analysis and methodology

Science.gov (United States)

Cauquil, J. M.; Seguineau, C.; Martin, J.-Y.; Benschop, T.

2016-05-01

The cooled IR detectors are used in a wide range of applications. Most of the time, the cryocoolers are one of the components dimensioning the lifetime of the system. The cooler reliability is thus one of its most important parameters. This parameter has to increase to answer market needs. To do this, the data for identifying the weakest element determining cooler reliability has to be collected. Yet, data collection based on field are hardly usable due to lack of informations. A method for identifying the improvement in reliability has then to be set up which can be used even without field return. This paper will describe the method followed by Thales Cryogénie SAS to reach such a result. First, a database was built from extensive expertizes of RM2 failures occurring in accelerate ageing. Failure modes have then been identified and corrective actions achieved. Besides this, a hierarchical organization of the functions of the cooler has been done with regard to the potential increase of its efficiency. Specific changes have been introduced on the functions most likely to impact efficiency. The link between efficiency and reliability will be described in this paper. The work on the two axes - weak spots for cooler reliability and efficiency - permitted us to increase in a drastic way the MTTF of the RM2 cooler. Huge improvements in RM2 reliability are actually proven by both field return and reliability monitoring. These figures will be discussed in the paper.

Development and Evaluation of a Sandia Cooler-based Refrigerator Condenser

Energy Technology Data Exchange (ETDEWEB)

Johnson, Terry A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kariya, Harumichi Arthur [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Leick, Michael T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Zimmerman, Mark D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Li, Manjie [Univ. of Maryland, College Park, MD (United States); Du, Yilin [Univ. of Maryland, College Park, MD (United States); Lee, Hoseong [Univ. of Maryland, College Park, MD (United States); Hwang, Yunho [Univ. of Maryland, College Park, MD (United States); Radermacher, Reinhard [Univ. of Maryland, College Park, MD (United States)

2015-07-01

This report describes the first design of a refrigerator condenser using the Sandia Cooler, i.e. air - bearing supported rotating heat - sink impeller. The project included ba seline performance testing of a residential refrigerator, analysis and design development of a Sandia Cooler condenser assembly including a spiral channel baseplate, and performance measurement and validation of this condenser system as incorporated into the residential refrigerator. Comparable performance was achieved in a 60% smaller volume package. The improved modeling parameters can now be used to guide more optimized designs and more accurately predict performance.

Market Assessment and Commercialization Strategy for the Radial Sandia Cooler

Energy Technology Data Exchange (ETDEWEB)

Goetzler, William [Navigant Consulting, Inc., Burlington, MA (United States); Shandross, Richard [Navigant Consulting, Inc., Burlington, MA (United States); Weintraub, Daniel [Navigant Consulting, Inc., Burlington, MA (United States); Young, Jim [Navigant Consulting, Inc., Burlington, MA (United States)

2014-02-01

This market assessment and commercialization report characterizes and assesses the market potential of the rotating heat exchanger technology developed at Sandia National Laboratories (SNL), known as the Radial Sandia Cooler. The RSC is a novel, motor-driven, rotating, finned heat exchanger technology. The RSC was evaluated for the residential, commercial, industrial, and transportation markets. Recommendations for commercialization were made based on assessments of the prototype RSC and the Sandia Cooler technology in general, as well as an in-depth analysis of the six most promising products for initial RSC commercialization.

Simulations of space charge neutralization in a magnetized electron cooler

Energy Technology Data Exchange (ETDEWEB)

Gerity, James [Texas A-M; McIntyre, Peter M. [Texas A-M; Bruhwiler, David Leslie [RadiaSoft, Boulder; Hall, Christopher [RadiaSoft, Boulder; Moens, Vince Jan [Ecole Polytechnique, Lausanne; Park, Chong Shik [Fermilab; Stancari, Giulio [Fermilab

2017-02-02

Magnetized electron cooling at relativistic energies and Ampere scale current is essential to achieve the proposed ion luminosities in a future electron-ion collider (EIC). Neutralization of the space charge in such a cooler can significantly increase the magnetized dynamic friction and, hence, the cooling rate. The Warp framework is being used to simulate magnetized electron beam dynamics during and after the build-up of neutralizing ions, via ionization of residual gas in the cooler. The design follows previous experiments at Fermilab as a verification case. We also discuss the relevance to EIC designs.

An approximately 4π tracking magnetic spectrometer for RHIC

International Nuclear Information System (INIS)

1987-01-01

A tracking magnetic spectrometer based on large Time Projection Chambers (TPC) is proposed to measure the momentum of charged particles emerging from the RHIC beam pipe at angles larger than four degrees and to identify the particle type for those beyond fifteen degrees with momenta up to 700 MeV/c, which is a large fraction of the final charged particles emitted by a low rapidity quark-gluon plasma

RHIC susceptibility to variations in systematic magnetic harmonic errors

International Nuclear Information System (INIS)

Dell, G.F.; Peggs, S.; Pilat, F.; Satogata, T.; Tepikian, S.; Trbojevic, D.; Wei, J.

1994-01-01

Results of a study to determine the sensitivity of tune to uncertainties of the systematic magnetic harmonic errors in the 8 cm dipoles of RHIC are reported. Tolerances specified to the manufacturer for tooling and fabrication can result in systematic harmonics different from the expected values. Limits on the range of systematic harmonics have been established from magnet calculations, and the impact on tune from such harmonics has been established

An FFAG-ERL at Cornell University for eRHIC prototyping and bright-beam applications

Energy Technology Data Exchange (ETDEWEB)

Hoffstaetter, Georg [Cornell University, Ithaca, NY (United States)

2016-07-01

Cornell University has prototyped technology essential for any high-brightness electron ERL. This includes a DC gun and an SRF injector Linac with world-record current and normalized brightness in a bunch train, a high-current CW cryomodule for 70 MeV energy gain, a high-power beam stop, and several diagnostics tools for high-current and high-brightness beams, e.g. slid measurements for 6-D phase-space densities, a fast wire scanner for beam profiles, and beam loos diagnostics. All these are now available to equip a one-cryomodule ERL, and laboratory space has been cleared out and is radiation shielded to install this ERL at Cornell. BNL has designed a multi-turn ERL for eRHIC, where beam is transported more than 20 times around the RHIC tunnel. The number of transport lines is minimized by using two non-scaling (NS) FFAG arcs. A collaboration between BNL and Cornell has been formed to investigate the new NS-FFAG optics and the multi-turn eRHIC ERL design by building a 4-turn, one-cryomodule ERL at Cornell. It has a NS-FFAG return loop built with permanent magnets and is meant to accelerate 40 mA beam to 250 MeV.

The e+, e- background at Relativistic Heavy Ion Collider (RHIC) generated by beam crossing

International Nuclear Information System (INIS)

Rhoades-Brown, M.J.; Ludlam, T.; Wu, J.; Bottcher, C.; Strayer, M.

1990-01-01

At the Brookhaven Relativistic Heavy Ion Collider (RHIC), fully stripped heavy ions will circulate in each of two rings up to beam energies of 250 (Z/A) GeV/u. During the beam crossing, the peripheral electromagnetic interaction between the heavy ions is sufficient to induce copious production of di-lepton pairs. These pairs are a potential source of background for the detectors at RHIC. In this paper we discuss the expected number of e + ,e - pairs, given the accepted initial luminosity value L of the collider. More importantly, we also calculate the differential cross sections for the angle, energy, rapidity and momentum distribution of the leptons. Using the luminosity L of the collider, these differential cross sections are normalized to the expected number of leptons per second. We restrict ourselves to e + ,e - production, a discussion of μ + ,μ - and τ + τ - distributions will be published later. The results are presented for the expected worst case, namely 197 Au 79+ ions at a beam kinetic energy of 100 GeV/u. This is forseen to be the heaviest ion for high luminosity experiments at RHIC. We note for a given energy, the cross section for e + ,e - production scales as Z 4 , where Z is the atomic number of the ions

The Forward GEM Tracker of STAR at RHIC

OpenAIRE

Simon, F.; Balewski, J.; Fatemi, R.; Hasell, D.; Kelsey, J.; Majka, R.; Page, B.; Plesko, M.; Underwood, D.; Smirnov, N.; Sowinski, J.; Spinka, H.; Surrow, B.; Visser, G.

2008-01-01

The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is in the process of designing and constructing a forward tracking system based on triple GEM technology. This upgrade is necessary to give STAR the capability to reconstruct and identify the charge sign of W bosons over an extended rapidity range through their leptonic decay mode into an electron (positron) and a neutrino. This will allow a detailed study of the flavor-separated spin str...

Model of a 80 K liner vacuum system for the 4.2 K cold bore of the SSCL 20 TeV proton collider

International Nuclear Information System (INIS)

Turner, W.

1993-09-01

In this paper we discuss a model for an 80 K liner system for the beam tube vacuum of the Superconducting Super Collider (SSC). The liner is a coaxial perforated tube fitting inside the ∼4.2 K bore tube of the SSC magnet cryostats. A liner of this type is useful for pumping the gas desorbed by synchrotron radiation out of the view of the radiation and for decoupling the beam current from the 4.2 K refrigeration plant capacity. Addition of cryosorber on the bore tube (e.g., charcoal) greatly increases the H 2 sorption capacity compared to the bare metal surface, thus lengthening the time between beam tube warmups. The model equations are useful for estimating the performance of the beam tube vacuum and for defining the experimental information necessary to make a prediction. Some analysis is also presented for 4.2 K and 20 K liners and a simple 4.2 K beam tube without a liner

Chemical freeze-out study in proton-proton collisions at RHIC and LHC energies

International Nuclear Information System (INIS)

Das, Sabita; Mishra, Debadeepti; Mohanty, Bedangadas; Chatterjee, Sandeep

2016-01-01

Particle multiplicities measured at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) facilities can be used to understand the chemical freeze-out dynamics. At chemical freeze-out (CFO), inelastic collisions cease and the freeze-out parameters can be determined using measured particle multiplicities within the framework of a statistical model. The statistical model has proven to be quite successful in describing the particle production from elementary p-p and e"+e"- collisions up to heavy-ion collisions. It helps to do a systematic study of the centrality and energy dependence of freeze-out parameters in heavy-ion collisions from lower SPS to higher LHC energies. The new data at LHC along with the RHIC data can be used to do such a systematic study in proton-proton collisions

Experimental characterization of the Hitrap Cooler trap with highly charged ions.

OpenAIRE

Fedotova, Svetlana

2013-01-01

The HITRAP (Highly charged Ions TRAP)facility is being set up and commissioned at GSI, Darmstadt. It will provide heavy, highly charged ions at low velocities to high-precision atomic physics experiments. Within this work the Cooler trap- the key element of the HITRAP facility was tested. The Cooler trap was assembled, aligned, and commissioned in trapping experiments with ions from off-line sources.The work performed within the scope of this thesis provided the baseline for further operation...

Preliminary studies on a magneto-optical procedure for aligning RHIC magnets

International Nuclear Information System (INIS)

Goldman, M.A.; Sikora, R.E.; Shea, T.J.

1993-01-01

Colloid dispersions of magnetite were used at SLAC and KEK to locate multipole magnet centers. The authors study here possible adaption of this method, to align RHIC magnets. A procedure for locating magnetic centers with respect to external fiducial markers, using electronic coordinate determination and digital TV image processing is described

Comparative analysis of linear motor geometries for Stirling coolers

Science.gov (United States)

R, Rajesh V.; Kuzhiveli, Biju T.

2017-12-01

Compared to rotary motor driven Stirling coolers, linear motor coolers are characterized by small volume and long life, making them more suitable for space and military applications. The motor design and operational characteristics have a direct effect on the operation of the cooler. In this perspective, ample scope exists in understanding the behavioural description of linear motor systems. In the present work, the authors compare and analyze different moving magnet linear motor geometries to finalize the most favourable one for Stirling coolers. The required axial force in the linear motors is generated by the interaction of magnetic fields of a current carrying coil and that of a permanent magnet. The compact size, commercial availability of permanent magnets and low weight requirement of the system are quite a few constraints for the design. The finite element analysis performed using Maxwell software serves as the basic tool to analyze the magnet movement, flux distribution in the air gap and the magnetic saturation levels on the core. A number of material combinations are investigated for core before finalizing the design. The effect of varying the core geometry on the flux produced in the air gap is also analyzed. The electromagnetic analysis of the motor indicates that the permanent magnet height ought to be taken in such a way that it is under the influence of electromagnetic field of current carrying coil as well as the outer core in the balanced position. This is necessary so that sufficient amount of thrust force is developed by efficient utilisation of the air gap flux density. Also, the outer core ends need to be designed to facilitate enough room for the magnet movement under the operating conditions.

Thermoelectric Coolers with Sintered Silver Interconnects

Science.gov (United States)

Kähler, Julian; Stranz, Andrej; Waag, Andreas; Peiner, Erwin

2014-06-01

The fabrication and performance of a sintered Peltier cooler (SPC) based on bismuth telluride with sintered silver interconnects are described. Miniature SPC modules with a footprint of 20 mm2 were assembled using pick-and-place pressure-assisted silver sintering at low pressure (5.5 N/mm2) and moderate temperature (250°C to 270°C). A modified flip-chip bonder combined with screen/stencil printing for paste transfer was used for the pick-and-place process, enabling high positioning accuracy, easy handling of the tiny bismuth telluride pellets, and immediate visual process control. A specific contact resistance of (1.4 ± 0.1) × 10-5 Ω cm2 was found, which is in the range of values reported for high-temperature solder interconnects of bismuth telluride pellets. The realized SPCs were evaluated from room temperature to 300°C, considerably outperforming the operating temperature range of standard commercial Peltier coolers. Temperature cycling capability was investigated from 100°C to 235°C over more than 200 h, i.e., 850 cycles, during which no degradation of module resistance or cooling performance occurred.

The impact of fouling on performance evaluation of evaporative coolers and condensers

Energy Technology Data Exchange (ETDEWEB)

Qureshi, B.A.; Zubair, S.M. [King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia). Mechanical Engineering Dept.

2005-11-15

Fouling of evaporative cooler and condenser tubes is one of the most important factors affecting their thermal performance, which reduces effectiveness and heat transfer capability with time. In this paper, the experimental data on fouling reported in the literature are used to develop a fouling model for this class of heat exchangers. The model predicts the decrease in heat transfer rate with the growth of fouling. A detailed model of evaporative coolers and condensers, in conjunction with the fouling model, is used to study the effect of fouling on the thermal performance of these heat exchangers at different air inlet wet bulb temperatures. The results demonstrate that fouling of tubes reduces gains in performance resulting from decreasing values of air inlet wet bulb temperature. It is found that the maximum decrease in effectiveness due to fouling is about 55 and 78% for the evaporative coolers and condensers, respectively, investigated in this study. For the evaporative cooler, the value of process fluid outlet temperature T{sub p,out} varies by 0.66% only at the clean condition for the ambient wet bulb temperatures considered. (author)

The electromagnetic calorimeter for the solenoidal tracker at RHIC. A Conceptual Design Report

Energy Technology Data Exchange (ETDEWEB)

Beddo, M.E.; Bielick, E.; Dawson, J.W. [Argonne National Lab., IL (United States)] [and others; The STAR EMC Collaboration

1993-09-22

This report discusses the following on the electromagnetic calorimeter for the solenoidal tracker at RHIC: conceptual design; the physics of electromagnetic calorimetry in STAR; trigger capability; integration into STAR; and cost, schedule, manpower, and funding.

Luminosity monitor topics for RHIC spin and AA, and pA interactions

International Nuclear Information System (INIS)

Underwood, D.

1998-01-01

This is a note to define topics to be studied in more depth for the Luminosity monitoring for Spin Asymmetries. My numerical examples here are to stimulate discussion and should be taken with a grain of salt. The RHIC Spin experiments will require a very high degree of coordination between the experiments and the accelerator. For example see AGS/RHIC/SN 035. In this note we list some of the issues to be considered in monitoring the relative luminosity between various beam-beam spin combinations and beam-gas combinations. We give simplified numerical examples of the problems encountered in doing the luminosity monitoring to the 10 -4 level. It is hoped that this will provide a framework for serious study of these problems with simulations and other means. Many of the issues may also be relevant to pA and AA running where there may be sizable beam-gas backgrounds

Wiggler as spin rotators for RHIC

International Nuclear Information System (INIS)

Luccio, A.; Conte, M.

1993-01-01

The spin of a polarized particle in a circular accelerator can be rotated with an arrangement of dipoles with field mutually perpendicular and perpendicular to the orbit. To achieve spin rotation, a given field integral value is required. The device must be designed in a way that the particle orbit is distorted as little as possible. It is shown that wigglers with many periods are suitable to achieve spin rotation with minimum orbit distortions. Wigglers are also more compact than more established structures and will use less electric power. Additional advantages include their use for non distructive beam diagnostics. Results are given for the Relativistic Heavy Ion Collider (RHIC) in the polarized proton mode

Can doubly strange dibaryon resonances be discovered at RHIC?

International Nuclear Information System (INIS)

Paganis, S. D.; Hoffmann, G. W.; Ray, R. L.; Tang, J.-L.; Udagawa, T.; Longacre, R. S.

2000-01-01

The baryon-baryon continuum invariant mass spectrum generated from relativistic nucleus + nucleus collision data may reveal the existence of doubly strange dibaryons not stable against strong decay if they lie within a few MeV of threshold. Furthermore, since the dominant component of these states is a superposition of two color-octet clusters which can be produced intermediately in a color-deconfined quark-gluon plasma (QGP), an enhanced production of dibaryon resonances could be a signal of QGP formation. A total of eight, doubly strange dibaryon states are considered for experimental search using the STAR detector (solenoidal tracker at RHIC) at the new Relativistic Heavy Ion Collider (RHIC). These states may decay to ΛΛ and/or pΞ - , depending on the resonance energy. STAR's large acceptance, precision tracking and vertex reconstruction capabilities, and large data volume capacity, make it an ideal instrument to use for such a search. Detector performance and analysis sensitivity are studied as a function of resonance production rate and width for one particular dibaryon which can directly strong decay to pΞ - , but not ΛΛ. Results indicate that such resonances may be discovered using STAR if the resonance production rates are comparable to coalescence model predictions for dibaryon bound states. (c) 2000 The American Physical Society

Monolithic circuit development for RHIC at Oak Ridge National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Alley, G.T.; Britton, C.L. Jr.; Kennedy, E.J.; Newport, D.F.; Wintenberg, A.L.; Young, G.R. [Oak Ridge National Laboratory, TN (United States)

1991-12-31

The work performed for RHIC at Oak Ridge National Laboratory during FY 91 is presented in this paper. The work includes preamplifier, analog memory, and analog-digital converter development for Dimuon Pad Readout, and evaluation and development of preamplifier-shapers for silicon strip readout. The approaches for implementation are considered as well as measured data for the various circuits that have been developed.

Observation of helium flow induced beam orbit oscillations at RHIC

International Nuclear Information System (INIS)

Montag, C.; Bonati, R.; Brennan, J.M.; Butler, J.; Cameron, P.; Ganetis, G.; He, P.; Hirzel, W.; Jia, L.X.; Koello, P.; Louie, W.; McIntyre, G.; Nicoletti, A.; Rank, J.; Roser, T.; Satogata, T.; Schmalzle, J.; Sidi-Yekhlef, A.; Sondericker, J.; Tallerico, T.

2006-01-01

Horizontal beam orbit jitter at frequencies around 10 Hz has been observed at RHIC for several years. The distinct frequencies of this jitter have been found at superconducting low-beta quadrupole triplet magnets around the ring, where they coincide with mechanical vibration modes of the cold masses. Recently, we have identified liquid helium flow as the driving force of these oscillations

Thermoelectric cooler concepts and the limit for maximum cooling

International Nuclear Information System (INIS)

Seifert, W; Hinsche, N F; Pluschke, V

2014-01-01

The conventional analysis of a Peltier cooler approximates the material properties as independent of temperature using a constant properties model (CPM). Alternative concepts have been published by Bian and Shakouri (2006 Appl. Phys. Lett. 89 212101), Bian (et al 2007 Phys. Rev. B 75 245208) and Snyder et al (2012 Phys. Rev. B 86 045202). While Snyder's Thomson cooler concept results from a consideration of compatibility, the method of Bian et al focuses on the redistribution of heat. Thus, both approaches are based on different principles. In this paper we compare the new concepts to CPM and we reconsider the limit for maximum cooling. The results provide a new perspective on maximum cooling. (paper)

Multiparticle production at RHIC and LHC: a classical point of view

International Nuclear Information System (INIS)

Krasnitz, A.; Venugopalan, R.

2000-01-01

We report results of our ongoing nonperturbative numerical study of a classical effective theory describing low-x partons in the central region of a heavy-ion collision. In particular, we give estimates of the initial transverse energies and multiplicities for a wide range of collision regimes, including those at RHIC and at LHC

Elliptic flow in Au+Au collisions at RHIC

Science.gov (United States)

Vale, Carla M.; PHOBOS Collaboration; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Decowski, M. P.; García, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Holynski, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Mignerey, A. C.; Ngyuen, M.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tang, J.-L.; Tonjes, M. B.; Trzupek, A.; van Nieuwenhuizen, G. J.; Verdier, R.; Veres, G.; Wolfs, F. L. H.; Wosiek, B.; Wozniak, K.; Wuosmaa, A. H.; Wyslouch, B.

2005-04-01

Elliptic flow is an interesting probe of the dynamical evolution of the dense system formed in the ultrarelativistic heavy ion collisions at the relativistic heavy ion collider (RHIC). The elliptic flow dependences on transverse momentum, centrality and pseudorapidity were measured using data collected by the PHOBOS detector, which offers a unique opportunity to study the azimuthal anisotropies of charged particles over a wide range of pseudorapidity. These measurements are presented, together with an overview of the analysis methods and a discussion of the results.

80 K - Helium circuit with innovative, gas-bearing, oil-free turbo compressor. Conception, realization, commissioning and test of the 80 K refrigeration supply for the superconducting electron source at HZB; 80 K - Helium-Kreis mit innovativem, gasgelagertem, oelfreiem Turbokompressor. Konzeption, Realisierung, Inbetriebnahme und Test der 80 K-Kaelteversorgung fuer die supraleitenden Elektronenquelle am HZB

Energy Technology Data Exchange (ETDEWEB)

Gloeckner, Felix [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Berlin (Germany)

2017-07-01

The system presented in this paper supplies the test module for the superconducting electron source (GunLab) at the Helmholtz-Zentrum Berlin (HZB) with 500 W cooling capacity at 80 K.Since direct evaporation of liquid nitrogen in the module is not desirable for safety reasons, the system operates with an intermediate helium circuit. In order to use not only the latent cold of liquid nitrogen, but also the sensitive component, a new concept consisting of a dual heat exchanger and a bath cryostat is used. The coldbox also contains an adjustable bypass with integrated electric heater for test purposes.A new type of warm compressor is used to circulate the helium. The turbo compressor is oil-free, gas-stored and in helium-tight semi-hermetic design. In order to take advantage of these unique properties, Fischer Engineering AG has adapted the turbo compressor for use with helium.The paper concludes with a test of the system and an insight into the current operating experience, as well as a preview of the next, larger version of bERLinPro. [German] Die in diesem Paper vorgestellte Anlage versorgt das Testmodul fuer die supraleitende Elektronenquelle (GunLab) am Helmholtz-Zentrum Berlin (HZB) mit 500 W Kuehlleistung bei 80 K. Da eine Direktverdampfung von Fluessigstickstoff im Modul aus Sicherheitsgruenden nicht erwuenscht ist, arbeitet die Anlage mit einem Heliumzwischenkreis. Um nicht nur die latente Kaelte des fluessigen Stickstoffs, sondern auch den sensiblen Anteil zu nutzen, wird ein neues Konzept, bestehend aus einem Dualwaermeuebertrager und einem Badkryostaten verwendet. Die Coldbox enthaelt fuer Testzwecke darueber hinaus einen regelbaren Bypass mit inte-griertem elektrischem Heizer. Fuer die Umwaelzung des Heliums kommt eine neue Art eines warmen Kompressors zum Einsatz. Der Turbokom-pressor ist oelfrei, gasgelagert und in heliumdichter halb-hermetischer Bauweise ausgefuehrt. Um dessen, in dieser Leistungsklasse einzigartigen Eigenschaften zu nutzen, wurde der

Improved cooler design of electric arc furnace refractory in mining industry using thermal analysis modeling and simulation

International Nuclear Information System (INIS)

Istadi, I.; Bindar, Y.

2014-01-01

Production of steel and nickel using the electric arc furnace should be focused on the intensification of energy. Improvement of energy efficiency of the most consuming facilities was achieved by improving the use of alternative energy minimization such as reducing the heat lost of hot gases, minimizing the heat radiated through refractory linings of metallurgical furnaces, and cooling the highly thermally stressed components. The refractory of electric arc furnace should be modified to achieve the best cooling system of the furnace. In this physical modeling and simulation works, four modification scenarios of wall refractory designs were simulated, i.e. refractory with basic design, refractory with deep plate coolers, refractory with extra plate coolers, and refractory with wall falling film coolers. Finally, the use of deep plate cooler and the existing waffle cooler system was considered to be the best design of efficient electric arc furnace operationally. - Highlights: • Electric arc furnace design should be focused on the intensification of energy. • Refractory of electric arc furnace were modified to achieve the best cooling system. • Four modification scenarios of the wall refractory designs were simulated. • Use of deep plate cooler and existing waffle cooler system is the best cooling

The Strongly Interacting Quark Gluon Plasma at RHIC and LHC

Directory of Open Access Journals (Sweden)

Tserruya Itzhak

2014-04-01

Full Text Available The study of heavy-ion collisions has currently unprecedented opportunities with two first class facilities, the Relativistic Heavy Ion Collider (RHIC at BNL and the Large Hadron Collider (LHC at CERN, and five large experiments ALICE, ATLAS, CMS, PHENIX and STAR producing a wealth of high quality data. Selected results recently obtained are presented on the study of flow, energy loss and direct photons.

The First Asymmetry Measurements in High-Energy Polarized Proton-Nucleus Collision at PHENIX-RHIC

Directory of Open Access Journals (Sweden)

Nakagawa Itaru

2017-01-01

Full Text Available The single spin asymmetries in very forward neutron production had been first observed about a decade ago at RHIC in transversely polarized proton + proton collision at √s = 200 GeV. Although neutron production near zero degrees is well described by the one-pion exchange (OPE framework, the OPE appeared to be not satisfactory to describe the observed analyzing power AN. The absorptive correction to the OPE generates the asymmetry as a consequence of a phase shift between the spin flip and non-spin flip amplitudes. However the amplitude predicted by the OPE is too small to explain the large observed asymmetries. Only the model which introduces interference between major pion and small a1-Reggeon exchange amplitudes has been successful in reproducing the experimental data. During RHIC Run-15, RHIC delivered polarized proton collisions with Au and Al for the first time, enabling the exploration of the mechanism of transverse single-spin asymmetries with nuclear collisions. A very striking A-dependence was discovered in very forward neutron production at PHENIX in transversely polarized proton + nucleus collision at √s = 200 GeV. Such a dependence has not been predicted from the existing framework which has been succesful in proton + proton collision. In this report, experimental and theoretical efforts are discussed to disentangle the mysterious A-dependence in the very forward neutron asymmetry.

RHIC SPIN PROGRAM: MACHINE ASPECTS AND RECENT PROGRESS

International Nuclear Information System (INIS)

ROSER, T.

1999-01-01

High energy polarized beam collisions will open up the unique physics opportunities of studying spin effects in hard processes. However, the acceleration of polarized beams in circular accelerators is complicated by the numerous depolarizing spin resonances. Using a partial Siberian Snake and a rf dipole that ensure stable adiabatic spin motion during acceleration has made it possible to accelerate polarized protons to 25 GeV at the Brookhaven AGS. Full Siberian Snakes and polarimeters are being developed for RHIC to make the acceleration of polarized protons to 250 GeV possible

DESIGN OF A FAST CHROMATICITY JUMP IN RHIC

International Nuclear Information System (INIS)

MONTAG, C.; KEWISCH, J.; BRUNO, D.; GANETIS, G.; LOUIE, W.

2003-01-01

During transition crossing in the .Relativistic Heavy Ion Collider (RHIC), chromaticities have to change sign. This sign change is partially accomplished by the γ t quadrupole jump; however, the resulting chromaticity jump is only Δξ x = 2.1 in the horizontal and Δξ y = 2.4 in the vertical plane. To increase the jump height, a dedicated chromaticity jump scheme has been designed, consisting of fast power supplies connected to six sextupoles per ring, which is capable of providing a chromaticity jump of Δξ = 6

Simulation of jet quenching at RHIC and LHC

International Nuclear Information System (INIS)

Lokhtin, I P; Snigirev, A M

2007-01-01

A model to simulate the jet quenching effect in ultrarelativistic heavy ion collisions is presented. The model is the fast Monte Carlo tool implemented to modify a standard PYTHIA jet event. The model has been generalized to the case of the 'full' heavy ion event (the superposition of soft, hydro-type state and hard multi-jets) using a simple and fast simulation procedure for soft particle production. The model is capable of reproducing the main features of the jet quenching pattern at RHIC and is applied to analyse novel jet quenching features at LHC

arXiv Jet Production at RHIC and LHC

CERN Document Server

Cunqueiro, Leticia

Recent results on jet production in heavy ion collisions at RHIC and the LHC are discussed, with emphasis on inclusive jet yields and semi-inclusive hadron-triggered and vector boson-triggered recoil jet yields as well as their azimuthal angular correlations. I will also discuss the constraints that these observables impose on the opacity of the medium, the flavour dependence of energy loss, the interplay of perturbative and non perturbative effects and the change of the degrees of freedom of the medium with the resolution of the probe.

Fan Cooler Operation in Kori 1 for Mitigating Severe Accident

International Nuclear Information System (INIS)

Suh, Nam Duk; Park, Jae Hong

2005-01-01

The Korea Ministry of Science and Technology (MOST) issued the 'Policy on Severe Accident of Nuclear Power Plants' in August 2001. According to the policy it was required for the licensee to develop a plant specific severe accident management guideline (SAMG) and to implement it. Thus the utility has made an implementation plan to develop SAMGs for operating plants. The SAMG for Kori unit 1 was submitted to the government on January 2004. Since then, the government trusted KINS to review the submitted SAMG in view of its feasibility and effectiveness. The first principle of the developed SAMG is to use only the available facilities as it is without introducing any system change. Because Kori-1 has no mitigative facility against combustible gases during severe accident, it relies heavily both on spray and on fan cooler systems to control the containment condition. Thus one of the issues raised during the review is to know whether the fan coolers which are designed for DBA LOCA can be effective in mitigating the severe accident conditions. This paper presents an analysis result of fan cooler operation in controlling the containment condition during severe accident of Kori 1

Note on polarized RHIC bunch arrangement

International Nuclear Information System (INIS)

Underwood, D.

1996-01-01

We discuss what combinations of bunch polarization in the two RHIC rings are necessary to do the physics measurements at various interaction regions. We also consider the bunches for both the pion inclusive and p-p elastic polarization measurements. Important factors to consider are the direction of the polarization with respect to the momentum in each bunch, the beam gas backgrounds, and the simulation of zero - polarization in one beam by averaging + and - helicity, and luminosity monitoring for normalization. These considerations can be addressed by setting the relative number of each of the 9 combinations possible at each of the 6 interaction regions. The combinations are (+ empty -) yellow X (+ empty -)blue, where yellow and blue are the counter-rotating rings

RHIC PC CNI POLARIMETER:STATUS AND PERFORMANCE from THE FIRST COLLIDER RUN

International Nuclear Information System (INIS)

JINNOUCHI, O.; ALEKSEEV, I.G.; BLAND, L.C.; BRAVAR, A.; BUNCE, G.; CADMAN, R.; DESHPANDE, A.D.; HAWAN, S.; FIELDS, D.E.; HUANG, H.; HUGHES, V.; IGO, G.; IMAI, K.; KANAVETS, V.P.; KIRYLUK, J.; KURITA, K.; LI, Z.; LOZOWSKI, W.; MACKAY, W.W.; MAKDISI, Y.; OGAWA, A.; RESCIA, S.; ROSER, T.; SAITO, N.; SPINKA, H.; SURROW, B.; SVIRIDA, D.N.; TOJO, J.; UNDERWOOD, D.; WOOD, J.

2002-01-01

Polarimeters using the proton carbon elastic scattering process in Coulomb Nuclear Interference (CNI) region were installed in two RHIC rings. Polarization measurements were successfully carried out with the high energy polarized proton beams for the first polarized pp collision run. The physics principles, performance, and polarization measurements are presented

TRANSVERSE OPTICS IMPROVEMENTS FOR RHIC RUN 4.

Energy Technology Data Exchange (ETDEWEB)

VAN ZEIJTS,J.

2004-07-05

The magnetic settings in RHIC are driven by an on-line model, and the quality of the resulting lattice functions depend on the correctness of the settings, and knowledge of the magnet transfer-functions. Here we first present the different inputs into the model, including dipole sextupole components, used to set tunes and chromaticities along the ramp. Based on an analysis of measured tunes along the FY03 polarized proton ramp, we present predictions for quadrupole transfer-function changes which have been implemented for the FY04 Au ramp. We show the improved model agreement for tunes along the ramp, and measured transverse phase-advance at store.

FEASIBILITY OF INCREASING THE ENERGY OF RHIC

International Nuclear Information System (INIS)

MACKAY, W.W.; JAIN, A.; LUCCIO, A.U.; PILAT, F.; ROSER, T.; TEPIKIAN, S.; TROBOJEVIC, D.

2001-01-01

In this paper we discuss the possibility of increasing the energy of beams in RHIC by as much as 30% with a modest trade-off in luminosity. The arc dipoles and quadrupoles were designed with considerable margin. For higher energies (>100 GeV/nucleon) the minimum β* may be required to increase as the interaction region triplets saturate. The separator magnets (DX) have the least margin for increased field, so we consider three scenarios: allowing for a small crossing angle with the present DX magnets, upgrading the DX magnets to higher strength, and permitting a crossing angle of ∼1degree by removing the DX magnets altogether

Objective and subjective image quality of primary and recurrent squamous cell carcinoma on head and neck low-tube-voltage 80-kVp computed tomography

Energy Technology Data Exchange (ETDEWEB)

Scholtz, Jan-Erik; Kaup, Moritz; Kraft, Johannes; Noeske, Eva-Maria; Schulz, Boris; Burck, Iris; Kerl, J.M.; Bauer, Ralf W.; Lehnert, Thomas; Vogl, Thomas J.; Wichmann, Julian L. [University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Scheerer, Friedrich [University Hospital Frankfurt, Department of Cranio-Maxillofacial and Plastic Facial Surgery, Frankfurt (Germany); Wagenblast, Jens [University Hospital Frankfurt, Department of Otolaryngology, Head and Neck Surgery, Frankfurt (Germany)

2015-03-26

To investigate low-tube-voltage 80-kVp computed tomography (CT) of head and neck primary and recurrent squamous cell carcinoma (SCC) regarding objective and subjective image quality. We retrospectively evaluated 65 patients (47 male, 18 female; mean age: 62.1 years) who underwent head and neck dual-energy CT (DECT) due to biopsy-proven primary (n = 50) or recurrent (n = 15) SCC. Eighty peak kilovoltage and standard blended 120-kVp images were compared. Attenuation and noise of malignancy and various soft tissue structures were measured. Tumor signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Subjective image quality was rated by three reviewers using 5-point grading scales regarding overall image quality, lesion delineation, image sharpness, and image noise. Radiation dose was assessed as CT dose index volume (CTDI{sub vol}). Interobserver agreement was calculated using intraclass correlation coefficient (ICC). Mean tumor attenuation (153.8 Hounsfield unit (HU) vs. 97.1 HU), SNR (10.7 vs. 8.3), CNR (8.1 vs. 4.8), and subjective tumor delineation (score, 4.46 vs. 4.13) were significantly increased (all P < 0.001) with 80-kVp acquisition compared to standard blended 120-kVp images. Noise of all measured structures was increased in 80-kVp acquisition (P < 0.001). Overall interobserver agreement was good (ICC, 0.86; 95 % confidence intervals: 0.82-0.89). CTDI{sub vol} was reduced by 48.7 % with 80-kVp acquisition compared to standard DECT (4.85 ± 0.51 vs. 9.94 ± 0.81 mGy cm, P < 0.001). Head and neck CT with low-tube-voltage 80-kVp acquisition provides increased tumor delineation, SNR, and CNR for CT imaging of primary and recurrent SCC compared to standard 120-kVp acquisition with an accompanying significant reduction of radiation exposure. (orig.)

STAR barrel electromagnetic calorimeter absolute calibration using 'minimum ionizing particles' from collisions at RHIC

International Nuclear Information System (INIS)

Cormier, T.M.; Pavlinov, A.I.; Rykov, M.V.; Rykov, V.L.; Shestermanov, K.E.

2002-01-01

The procedure for the STAR Barrel Electromagnetic Calorimeter (BEMC) absolute calibrations, using penetrating charged particle hits (MIP-hits) from physics events at RHIC, is presented. Its systematic and statistical errors are evaluated. It is shown that, using this technique, the equalization and transfer of the absolute scale from the test beam can be done to a percent level accuracy in a reasonable amount of time for the entire STAR BEMC. MIP-hits would also be an effective tool for continuously monitoring the variations of the BEMC tower's gains, virtually without interference to STAR's main physics program. The method does not rely on simulations for anything other than geometric and some other small corrections, and also for estimations of the systematic errors. It directly transfers measured test beam responses to operations at RHIC

Conceptual design of the Relativistic Heavy Ion Collider: RHIC

International Nuclear Information System (INIS)

1986-05-01

The complete Relativistic Heavy Ion Collider (RHIC) facility will be a complex set of accelerators and beam transfer equipment connecting them. A significant portion of the total facility either exists or is under construction. Two existing Tandem Van de Graaff accelerators will serve for the initial ion acceleration. Ions with a charge of -1 would be accelerated from ground to +15 MV potential, pass through a stripping foil, and accelerate back to ground potential, where they would pass through a second stripping foil. From there the ions will traverse a long transfer line to the AGS tunnel and be injected into the Booster accelerator. The Booster accelerates the ion bunch, and then the ions pass through one more stripper and then enter the Alternating Gradient Synchrotron (AGS), where they are accelerated to the top AGS energy and transferred to the collider. Bending and focusing of ion beams is to be achieved by superconducting magnets. The physics goals behind the RHIC are enumerated, particularly as regards the study of quark matter and the characteristics of high energy nucleus-nucleus collisions. The design of the collider and all its components is described, including the injector, the lattice, magnet system, cryogenic and vacuum systems, beam transfer, injection, and dump, rf system, and beam instrumentation and control system. Also given are cost estimates, construction schedules, and a management plan

Optimization of a microfluidic electrophoretic immunoassay using a Peltier cooler.

Science.gov (United States)

Mukhitov, Nikita; Yi, Lian; Schrell, Adrian M; Roper, Michael G

2014-11-07

Successful analysis of electrophoretic affinity assays depends strongly on the preservation of the affinity complex during separations. Elevated separation temperatures due to Joule heating promotes complex dissociation leading to a reduction in sensitivity. Affinity assays performed in glass microfluidic devices may be especially prone to this problem due to poor heat dissipation due to the low thermal conductivity of glass and the large amount of bulk material surrounding separation channels. To address this limitation, a method to cool a glass microfluidic chip for performing an affinity assay for insulin was achieved by a Peltier cooler localized over the separation channel. The Peltier cooler allowed for rapid stabilization of temperatures, with 21°C the lowest temperature that was possible to use without producing detrimental thermal gradients throughout the device. The introduction of cooling improved the preservation of the affinity complex, with even passive cooling of the separation channel improving the amount of complex observed by 2-fold. Additionally, the capability to thermostabilize the separation channel allowed for utilization of higher separation voltages than what was possible without temperature control. Kinetic CE analysis was utilized as a diagnostic of the affinity assay and indicated that optimal conditions were at the highest separation voltage, 6 kV, and the lowest separation temperature, 21°C, leading to 3.4% dissociation of the complex peak during the separation. These optimum conditions were used to generate a calibration curve and produced 1 nM limits of detection, representing a 10-fold improvement over non-thermostated conditions. This methodology of cooling glass microfluidic devices for performing robust and high sensitivity affinity assays on microfluidic systems should be amenable in a number of applications. Copyright © 2014 Elsevier B.V. All rights reserved.

Spin physics at RHIC

International Nuclear Information System (INIS)

Tannenbaum, M.J.

1996-01-01

Operation of RHIC with two beams of highly polarized protons (70%, either longitudinal or transverse) at high luminosity L = 2 x 10 32 cm -2 sec -1 for two months/year will allow the STAR and PHENIX detectors to perform high statististics studies of polarization phenomena in the perturbative region of hard scattering where both QCD and ElectroWeak theory make detailed predictions for polarization effects. The collision c.m. energy, √s = 200 - 500 GeV, represents a new domain for the study of spin. Direct photon production will be used to measure the gluon polarization in the polarized proton. A new twist comes from W-boson production which is expected to be 100% parity violating and will thus allow measurements of flavor separated Quark and antiquark (u, bar u, d, bar d) polarization distributions. Searches for parity violation in strong interaction processes such as jet and leading particle production will be a sensitive way to look for new physics beyond the standard model, one possibility being quark substructure

Polarized protons at RHIC

International Nuclear Information System (INIS)

Tannenbaum, M.J.

1990-12-01

The Physics case is presented for the use of polarized protons at RHIC for one or two months each year. This would provide a facility with polarizations of approx-gt 50% high luminosity ∼2.0 x 10 32 cm -2 s -1 , the possibility of both longitudinal and transverse polarization at the interaction regions, and frequent polarization reversal for control of systematic errors. The annual integrated luminosity for such running (∼10 6 sec per year) would be ∫ Ldt = 2 x 10 38 cm -2 -- roughly 20 times the total luminosity integrated in ∼ 10 years of operation of the CERN Collider (∼10 inverse picobarns, 10 37 cm -2 ). This facility would be unique in the ability to perform parity-violating measurements and polarization test of QCD. Also, the existence of p-p collisions in a new energy range would permit the study of ''classical'' reactions like the total cross section and elastic scattering, etc., and serve as a complement to measurements from p-bar p colliders. 11 refs

Enhanced dilepton radiation at RHIC

CERN Document Server

Toia, Alberica

2009-01-01

Recently, there is growing evidence that a new state of matter is formed in Au+Au collisions at RHIC: a strongly coupled Quark Gluon Plasma of partonic degrees of freedom which develops a collective motion. Dilepton spectra are not affected by strong interaction and can therefore probe the whole time evolution of the collision. Thus they may be sensitive to the onset of deconfinement, chiral symmetry restoration, as well as the production of thermal photons. The PHENIX experiment measured the production of e+e− pairs in p+p and Au+Au collisions at . An enhanced dilepton yield in the mass range is measured. The excess increases faster with centrality than the number of participating nucleons, and is concentrated at . At higher pT the excess below 300 MeV/c2 has been related to an enhanced production of direct photons, possibly of thermal origin.