Download or read book COMMISSIONING AND OPERATION OF THE CEBAF 100 MV CRYOMODULES written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Continuous Electron Beam Accelerator Facility (CEBAF) energy upgrade from 6 GeV to 12 GeV includes the installation of ten new 100 MV cryomodules and RF systems. The superconducting RF cavities are designed to operate CW at a maximum accelerating gradient of 19.3 MV/m. To support the higher gradients and higher Q{sub L} (≈ 3 x 107), a new RF system has been developed and is being installed to power and control the cavities. The RF system employs digital control and 13 kW klystrons. Recently, two of these cryomodules and associated RF hardware and software have been installed and commissioned in the CEBAF accelerator. Electrons at linac currents up to 540?A have been successfully accelerated and used for nuclear physics experiments. This paper reports on the commissioning and operation of the RF system and cryomodules.

Download or read book Commissioning of the CEBAF Cryomodules written by and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: When complete, the Continuous Electron Beam Accelerator Facility will house a 4 GeV recirculating linear accelerator containing 42 1/4 cryomodules arrayed in two antiparallel linacs and an injector. Currently, over half of the cryomodules have been installed. Each cryomodule contains eight superconducting niobium 5-cell rf cavities that operate at 1.497 GHz [1]. A cryomodule must provide an energy gain of 20 MeV to the 200 mu-A beam [2]. The resultant dynamic heat load must be less than 45 W. The cavity parameters that are measured during the commissioning process include the external Q's of the cavity ports, the unloaded Q (Q0) of the cavity as a function of accelerating gradient, and the maximum operating gradient of the cavity. The sensitivity of the resonant frequency to changes in pressure and gradient is also measured. Finally, the mechanical tuners are cycled and characterized. In all cases, the performance of CEBAF cryomodules has exceeded the design requirements. A portable test stand allows local control of the rf system and provides automated data acquisition. This paper describes the cryomodule commissioning hardware, software, and measurements.

Download or read book Performance of First C100 Cryomodules for the CEBAF 12 GeV Upgrade Project written by and published by . This book was released on 2012 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Thomas Jefferson National Accelerator Facility is currently engaged in the 12 GeV Upgrade Project. The goal of the project is a doubling of the available beam energy of CEBAF from 6 GeV to 12 GeV. This increase in beam energy will be due primarily to the construction and installation of ten "C100" cryomodules in the CEBAF linacs. The C100 cryomodules are designed to deliver an average 108 MV each from a string of eight seven-cell, electropolished superconducting RF cavities operating at an average accelerating gradient of 19.2 MV/m. The new cryomodules fit in the same available linac space as the original CEBAF 20 MV cryomodules. Cryomodule production started in September 2010. Initial acceptance testing started in June 2011. The first two C100 cryomodules were installed and tested from August 2011 through October 2011, and successfully operated during the last period of the CEBAF 6 GeV era, which ended in May 2012. This paper will present the results of acceptance testing and commissioning of the C100 style cryomodules to date.

Download or read book CEBAF Upgrade written by and published by . This book was released on 2014 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Thomas Jefferson National Accelerator Facility is currently engaged in the 12 GeV Upgrade Project. The goal of the 12 GeV Upgrade is a doubling of the available beam energy of the Continuous Electron Beam Accelerator Facility (CEBAF) from 6 GeV to 12 GeV. This increase in beam energy will be due in large part to the addition of ten C100 cryomodules plus associated new RF in the CEBAF linacs. The C100 cryomodules are designed to deliver 100 MeV per installed cryomodule. Each C100 cryomodule is built around a string of eight seven-cell, electro-polished, superconducting RF cavities. While an average performance of 100MV per cryomodule is needed to achieve the overall 12 GeV beam energy goal, the actual performance goal for the cryomodules is an average energy gain of 108 MV to provide operational headroom. Cryomodule production started in December 2010. All ten of the C100 cryomodules are installed in the linac tunnels and are on schedule to complete commissioning by September 2013. Performance during Commissioning has ranged from 104 MV to 118 MV. In May, 2012 a test of an early C100 achieved 108 MV with full beam loading. This paper will discuss the performance of the C100 cryomodules along with operational challenges and lessons learned for future designs.

Download or read book CEBAF Cryomodule Commissioning in the South Linac written by and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: When complete, the Continuous Electron Beam Accelerator Facility will house a 4 GeV recirculating linear accelerator containing 42 1/4 cryomodules arrayed in two antiparallel linacs and an injector. Currently, 38 1/4 cryomodules have been installed. Each cryomodule contains eight superconducting niobium 5-cell rf cavities that operate at 1.497 GHz [1]. A cryomodule must provide an energy gain of 20 MeV to the 200 mu-A beam [2]. The resultant dynamic heat load must be less than 45 W. The cavity parameters that are measured during the commissioning process include the external Q's (Q{sub ext}) of the cavity ports, the unloaded Q (Q0) of the cavity as a function of accelerating gradient, and the maximum operating gradient of the cavity [3]. Finally, the mechanical tuners are cycled and characterized. A portable test stand allows local control of the rf system and provides automated data acquisition. During the period from April 1993 through September 1993, 16 of the 20 cryomodules installed in the South Linac were commissioned. All cryomodules tested in the South Linac meet or exceed the CEBAF specifications. This paper describes the results of the commissioning of the first 10 cryomodules in the South Linac.

Download or read book Commissioning and Operational Experience With an Intermediate Upgrade Cryomodule for the CEBAF 12 GeV Upgrade written by G. Davis and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Three cryomodules have been designed and built as intermediate prototypes for the CEBAF 12 GeV upgrade. This paper will discuss the commissioning and operational experience with the second of these cryomodules, which was installed and commissioned in the Jefferson Lab 10 kW Free Electron Laser Facility. Within the cryomodule are eight 7-cell, 1497 MHz cavities. It was designed to accelerate 1 mA of beam in excess of 70 MV and to have the same footprint as a standard CEBAF cryomodule. The cryomodule was installed in parallel with the FEL beam line in the spring of 2004 and characterized simultaneous with beam delivery. It was installed in the beam line in the early summer of 2004 and has since been operated as part of an energy recovered linac with 5 mA of beam current and 75 MV accelerating gradient for extended periods of time. Additionally, it was operated at 1 mA of beam current and 80 MV of accelerating gradient for several hours without a trip. In the latter operating mode the beam current was limited by the injector setup.

Download or read book Cebaf SRF Performance During Initial 12 GeV Commissioning written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Continuous Electron Beam Accelerator Facility (CEBAF) energy upgrade from 6 GeV to 12 GeV includes the installation of eleven new 100 MV cryomodules (88 cavities). The superconducting RF cavities are designed to operate CW at an accelerating gradient of 19.3 MV/m with a QL of 3×107. Not all the cavities were operated at the minimum gradient of 19.3 MV/m with the beam. Though the initial 12 GeV milestones were achieved during the initial commissioning of CEBAF, there are still some issues to be addressed for long term reliable operation of these modules. This paper reports the operational experiences during the initial commissioning and the path forward to improve the performance of C100 (100 MV) modules.

Download or read book 12 GeV Upgrade Project Cryomodule Production written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Thomas Jefferson National Accelerator Facility (Jefferson Lab) is producing ten 100+MV SRF cryomodules (C100) as part of the CEBAF 12 GeV Upgrade Project. Once installed, these cryomodules will become part of an integrated accelerator system upgrade that will result in doubling the energy of the CEBAF machine from 6 to 12 GeV. This paper will present a complete overview of the C100 cryomodule production process. The C100 cryomodule was designed to have the major components procured from private industry and assembled together at Jefferson Lab. In addition to measuring the integrated component performance, the performance of the individual components is verified prior to being released for production and assembly into a cryomodule. Following a comprehensive cold acceptance test of all subsystems, the completed C100 cryomodules are installed and commissioned in the CEBAF machine in preparation of accelerator operations. This overview of the cryomodule production process will include all principal performance measurements, acceptance criterion and up to date status of current activities.

Download or read book Superconducting Radiofrequency Technology for Accelerators written by Hasan Padamsee and published by John Wiley & Sons. This book was released on 2023-05-15 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: Superconducting Radiofrequency Technology for Accelerators Single source reference enabling readers to understand and master state-of-the-art accelerator technology Superconducting Radiofrequency Technology for Accelerators provides a quick yet thorough overview of the key technologies for current and future accelerators, including those projected to enable breakthrough developments in materials science, nuclear and astrophysics, high energy physics, neutrino research and quantum computing. The work is divided into three sections. The first part provides a review of RF superconductivity basics, the second covers new techniques such as nitrogen doping, nitrogen infusion, oxide-free niobium, new surface treatments, and magnetic flux expulsion, high field Q slope, complemented by discussions of the physics of the improvements stemming from diagnostic techniques and surface analysis as well as from theory. The third part reviews the on-going applications of RF superconductivity in already operational facilities and those under construction such as light sources, proton accelerators, neutron and neutrino sources, ion accelerators, and crab cavity facilities. The third part discusses planned accelerator projects such as the International Linear Collider, the Future Circular Collider, the Chinese Electron Positron Collider, and the Proton Improvement Plan-III facility at Fermilab as well as exciting new developments in quantum computing using superconducting niobium cavities. Written by the leading expert in the field of radiofrequency superconductivity, Superconducting Radiofrequency Technology for Accelerators covers other sample topics such as: Fabrication and processing on Nb-based SRF structures, covering cavity fabrication, preparation, and a decade of progress in the field SRF physics, covering zero DC resistance, the Meissner effect, surface resistance and surface impedance in RF fields, and non-local response of supercurrent N-doping and residual resistance, covering trapped DC flux losses, hydride losses, and tunneling measurements Theories for anti-Q-slope, covering the Xiao theory, the Gurevich theory, non-equilibrium superconductivity, and two fluid model based on weak defects Superconducting Radiofrequency Technology for Accelerators is an essential reference for high energy physicists, power engineers, and electrical engineers who want to understand the latest developments of accelerator technology and be able to harness it to further research interest and practical applications.

Download or read book Cryostat Design written by J.G. Weisend II and published by Springer. This book was released on 2016-08-12 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book enables the reader to learn the fundamental and applied aspects of practical cryostat design by examining previous design choices and resulting cryostat performance. Through a series of extended case studies the book presents an overview of existing cryostat design covering a wide range of cryostat types and applications, including the magnet cryostats that comprise the majority of the Large Hadron Collider at CERN, space-borne cryostats containing sensors operating below 1 K, and large cryogenic liquid storage vessels. It starts with an introductory section on the principles of cryostat design including practical data and equations. This section is followed by a series of case studies on existing cryostats, describing the specific requirements of the cryostat, the challenges involved and the design choices made along with the resulting performance of the cryostat. The cryostat examples used in the studies are chosen to cover a broad range of cryostat applications and the authors of each case are leading experts in the field, most of whom participated in the design of the cryostats being described. The concluding chapter offers an overview of lessons learned and summarises some key hints and tips for practical cryostat design. The book will help the reader to expand their knowledge of many disciplines required for good cryostat design, including the cryogenic properties of materials, heat transfer and thermal insulation, instrumentation, safety, structures and seals.

Download or read book Field Emission and Consequences as Observed and Simulated for CEBAF Upgrade Cryomodules written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: High gamma and neutron radiation levels were monitored at the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Laboratory (JLab) after installation of new cavity cryomodules and initial test runs in the frame of the ongoing 12 GeV upgrade program. The dose rates scaled exponentially with cavity accelerating fields, but were independent of the presence of an electron beam in the accelerator. Hence, field emission (FE) is the source of origin. This has led to concerns regarding the high field operation (100 MV per cryomodule) in the future 12 GeV era. Utilizing supercomputing, novel FE studies have been performed with electrons tracked through a complete cryomodule. It provides a principal understanding of experimental observations as well as ways to mitigate FE as best as practicable by identification of problematic cavities.

Download or read book Reviews of Accelerator Science and Technology written by Alexander W. Chao and published by World Scientific. This book was released on 2013-01-28 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is dedicated to superconducting technology and its applications, including superconducting magnets (SC magnets) and superconducting radio-frequency (SRF) cavities.

Download or read book Reviews Of Accelerator Science And Technology Volume 5 Applications Of Superconducting Technology To Accelerators written by Alexander Wu Chao and published by World Scientific. This book was released on 2013-01-28 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past several decades major advances in accelerators have resulted from breakthroughs in accelerator science and accelerator technology. After the introduction of a new accelerator physics concept or the implementation of a new technology, a leap in accelerator performance followed. A well-known representation of these advances is the Livingston chart, which shows an exponential growth of accelerator performance over the last seven or eight decades. One of the breakthrough accelerator technologies that support this exponential growth is superconducting technology. Recognizing this major technological advance, we dedicate Volume 5 of Reviews of Accelerator Science and Technology (RAST) to superconducting technology and its applications.Two major applications are superconducting magnets (SC magnets) and superconducting radio-frequency (SRF) cavities. SC magnets provide much higher magnetic field than their room-temperature counterparts, thus allowing accelerators to reach higher energies with comparable size as well as much reduced power consumption. SRF technology allows field energy storage for continuous wave applications and energy recovery, in addition to the advantage of tremendous power savings and better particle beam quality. In this volume, we describe both technologies and their applications. We also include discussion of the associated R&D in superconducting materials and the future prospects for these technologies.

Download or read book Performance of the Cebaf Prototype Cryomodule Renascence written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The prototype cryomodule Renascence was constructed as an energy building block for securing 6 GeV operation of CEBAF and to validate design elements for future CEBAF upgrade modules. These elements include the new "HG" and "LL" 7-cell cavity designs and a new tuner design.[1,2] Issues were identified during initial testing in 2005. The module has been reworked to address the issues with thermal stability, component breakage, and tuner motion. In addition, opportunity was taken to employ upgraded cleaning and assembly techniques for the cavity string. The HOM coupler heating issue was resolved, and seven of the eight cavities in the cryomodule have run stably at an average of 20 MV/m CW. The cryogenic, rf, and mechanical performance of the cryomodule are presented. Commissioning in CEBAF has just been completed in October 2007.

Download or read book A 100 MV Cryomodule for CW Operation written by Charles Reece and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A cryomodule designed for high-gradient CW operation has been built at Jefferson Lab. The Renascence cryomodule is the final prototype of a design for use in the 12 GeV CEBAF upgrade. The module uses eight 7-cell 1497 MHz cavities to be individually powered by 13 kW klystrons. Specifications call for providing>109 MV CW with

Download or read book Overview and Lessons Learned of the Jefferson Lab Cryomodule Production for the CEBAF 12 GeV Upgrade written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab is nearing completion of an energy upgrade from 6 to 12 GeV. An integral part of the upgrade is the addition of ten new cryomodules, each consisting of eight seven-cell superconducting radio-frequency (SRF) cavities. An average performance of 100+MV of acceleration per cryomodule is needed to achieve the 12 GeV beam energy goal. The production methodology was for industry to provide and deliver the major components to Jefferson Lab, where they were tested and assembled into cryomodules. The production process begins with an inspection upon receiving of all major components followed by individual performance qualification testing. The SRF cavities received their final chemical processing and cleaning at Jefferson Lab. The qualified components along with all associated hardware and instrumentation are assembled, tested, installed into CEBAF and run through an integrated system checkout in preparation for beam operations. The production process is complete and one of the first completed cryomodules has successfully produced 108 MV of acceleration with a linac beam current of 465?A.

Download or read book Production and Performance of the CEBAF Upgrade Cryomodule Intermediate Prototypes written by T. Powers and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We have installed two new cryomodules, one in the nuclear physics accelerator (CEBAF) and the other in the Free Electron Laser (FEL) of Jefferson Lab. The new cryomodules consist of 7-cell cavities with the original CEBAF cell shape and were designed to deliver gradients of 70 MV/module. Several significant design innovations were demonstrated in these cryomodules. This paper describes the production procedures, the performance characteristics of these cavities in vertical tests, results of tests in the new cryomodule test facility (CMTF) as well as the commissioning in the CEBAF tunnel and FEL. Performances and limitations after installation in the accelerators are discussed in this paper along with improvements proposed for future cryomodules.