Download or read book Q Degradation in Superconducting Niobium Cavities May 1991 written by Kenji Saito and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observation of Q degradation in Superconducting Niobium Cavities Due to Cooldown Conditions December 1991 written by Kenji Saito and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observation of Q degradation in Superconducting Niobium Cavities Due to Cooldown Conditions written by and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book EPAC 92 written by H. Henke and published by Atlantica Séguier Frontières. This book was released on 1992 with total page 942 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Q degradation in High Purity Niobium Cavities dependence on Temperature and RRR Valve 1992 written by Kenji Saito and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conference Record of the 1991 IEEE Particle Accelerator Conference written by and published by . This book was released on 1991 with total page 728 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Q degradation in High Purity Niobium Cavities Dependence on Temperature and RRR values March 1992 written by Kenji Saito and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Cryogenic Engineering written by Peter Kittel and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 2054 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Oregon Convention Center, Portland, Oregon, was the venue for the 1997 Cryogenic Engineering Conference. The meeting was held jointly with the International Cryogenic Materials Conference. John Barclay, of the University of Victoria, and David Smathers, of Cabot Performance Materials, were conference chairmen. Portland is the home of Northwest Natural Gas, a pioneer in the use of liquid natural gas, and Portland State University, where cryogenic research has long been conducted. The program consisted of 350 CEC papers, considerable more than CEC-95. This was the largest number of papers ever submitted to the CEC. Of these, 263 papers are published here, in Volume 43 of Advances in Cryogenic Engineering. Once again the volume is published in two books. CEC PAPER REVIEW PROCESS Since 1954 Advances in Cryogenic Engineering has been the archival publication of papers presented at the biennial CEC!ICMC conferences. The publication includes invited, unsolicited, and government sponsored research papers in the research areas of cryogenic engineering and applications. All of the papers published must (1) be presented at the conference, (2) pass the peer review process, and (3) report previously unpublished theoretical studies, reviews, or advances in cryogenic engineering.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1992-10 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanostructural Features Degrading the Performance of Superconducting Radio Frequency Niobium Cavities Revealed by Transmission Electron Microscopy and Electron Energy Loss Spectroscopy written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoscale defect structure within the magnetic penetration depth of ~100 nm is key to the performance limitations of niobium superconducting radio frequency cavities. Using a unique combination of advanced thermometry during cavity RF measurements, and TEM structural and compositional characterization of the samples extracted from cavity walls, we discover the existence of nanoscale hydrides in electropolished cavities limited by the high field Q slope, and show the decreased hydride formation in the electropolished cavity after 120°C baking. Furthermore, we demonstrate that adding 800°C hydrogen degassing followed by light buffered chemical polishing restores the hydride formation to the pre-120°C bake level. We also show absence of niobium oxides along the grain boundaries and the modifications of the surface oxide upon 120°C bake.
Download or read book Analysis of the Medium Field Q slope in Superconducting Cavities Made of Bulk Niobium written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The quality factor of superconducting radio-frequency cavities made of high purity, bulk niobium increases with rf field in the medium field range (peak surface magnetic field between 20 and about 100 mT). The causes for this effect are not clear yet. The dependence of the surface resistance on the peak surface magnetic field is typically linear and quadratic. This contribution will present an analysis of the medium field Q-slope data measured on cavities treated with buffered chemical polishing (BCP) at Jefferson Lab, as function of different treatments such as post-purification and low-temperature baking. The data have been compared with a model involving a combination of heating and of hysteresis losses due to ''strong-links'' formed or weakened at niobium surfaces during oxidation, which correlate to [delta][Delta]/kT[sub c] changes by baking.
Download or read book Hydrogen in Materials and Vacuum Systems written by Ganapati R. Myneni and published by American Institute of Physics. This book was released on 2003-07-16 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: All papers were peer-reviewed. Hydrogen plays a key role in materials, beneficial in some cases, problematic in others. In all such systems a detailed understanding of the hydrogen-based interaction is necessary for control, improvements, and for possible new applications. This hydrogen workshop proceeding incorporates contributions from semi-conducting, normal conducting (metals) and superconducting materials, as well as vacuum communities who deal with the hydrogen-materials issue. The technical areas covered in these proceedings include hydrogen in materials, hydrogen interactions and dynamics in semiconductors, hydrogen adsorption-storage-generation and distribution, hydrogen in niobium, hydrogen in vacuum systems, gaseous hydrogen accelerator structures, and magnetically suspended liquid hydrogen transfer lines.
Download or read book High Gradient Superconducting Niobium Cavities written by Peter Kneisel and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Q Disease on 350 MHZ Superconducting Spoke Cavities written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Q disease, i.e., an increase of RF surface resistance due to hydride precipitation, has been investigated with 350-MHz spoke cavities. This phenomenon was studied extensively in early 1990s with cavities at frequencies>1 GHz. This is possibly due to the fact that the lower-frequency cavities were believed to show insignificant effect. However, early 500-MHz KEK elliptical cavities and JAERI 130-MHz quarter wave resonators have shown significant Q degradation, suggesting that this disease can be a serious problem with lower-frequency cavities as well. Since there were no quantitative data with 350-MHz cavities, we decided to measure our two spoke cavities. Our spoke cavities were made of RRR(almost equal to)250 niobium and were chemically polished (almost equal to)150 microns. A few series of systematic tests have shown that our spoke cavities do not show any Q0 degradation up to (almost equal to)24 hours of holding the cavity at 100 K. However it starts showing degradation if it is held for a longer time and the additional loss due to the Q disease increases linearly. It was also found that our spoke cavity recovers from Q disease if it is warmed up to 150 K or higher for 12 hours.
Download or read book RF Superconductivity for Accelerators written by Hasan Padamsee and published by John Wiley & Sons. This book was released on 2008-02-26 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces some of the key ideas of this exciting field, using a pedagogic approach, and presents a comprehensive overview of the field. It is divided into four parts. The first part introduces the basic concepts of microwave cavities for particle acceleration. The second part is devoted to the observed behavior of superconducting cavities. In the third part,general issues connected with beam-cavity interaction and the related issues for the critical components are covered. The final part discusses applications of superconducting cavities to frontier accelerators of the future, drawing heavily on the examples that are in their most advanced stage. Each part of the book ends in a Problems section to illustrate and amplify text material as well as draw on example applications of superconducting cavities to existing and future accelerators.
Download or read book Physics Briefs written by and published by . This book was released on 1993 with total page 1116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
