CRYOCOOLERS 13 A publication of the International Cryocooler Conference

CRYOCOOLERS 13

Edited by

Ronald G. Ross^ Jr. Jet Propulsion Laboratory California Institute of Technology Pasadena, California

^Spriinee r Proceedings of the 13th International Cryocooler Conference, held March 29-April 1, 2004 in New Orleans, Louisiana ISSN: 1570-2235 ISBN: 0-387-23901-4 Printed on acid-free paper. ©2005 Springer Science+Business Media, Inc. All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, Inc., 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. Printed in the United States of America. 987654321 SPIN 11335245 springeronline.com Preface

The last two years have witnessed a continuation in the breakthrough shift toward pulse tube cryocoolers for long-life, high-reliability cryocooler applications. New this year are papers de­ scribing the development of very large pulse tube cryocoolers to provide up to 1500 watts of cooling for industrial applications such as cooling the superconducting magnets of Mag-lev trains, coolmg superconducting cables for the power mdustry, and liquefymg natural gas. Pulse tube coolers can be driven by several competing compressor technologies. One class of pulse tube coolers is referred to as "Stirling type" because they are based on the linear Oxford Stirling-cooler type compressor; these generally provide coolmg m the 30 to 100 K temperature range and operate ^t frequencies from 30 to 60 Hz. A second type of pulse tube cooler is the so-called "Gifford-McMahon type." Pulse tube coolers of this type use a G-M type compressor and lower frequency operation (~1 Hz) to achieve temperatures in the 2 to 10 K temperature range. The third type of pulse tube cooler is driven by a thermoacoustic oscillator, a heat engine that functions well in remote environments where electricity is not readily available. All three types are described, and in total, nearly half of this proceedings covers new developments in the pulse tube arena. Complementing the work on low-temperature pulse tube and Gifford-McMahon cryocoolers is substantial continued progress on rare earth regenerator materials. These technologies con­ tinue to make great progress in opening up the 2 -10 K market. Also in the commercial sector, continued interest is being shown in the development of long-life, low-cost cryocoolers for the emerging high temperature superconductor electronics market, particularly the cellular telephone base-station market. At higher temperature levels, closed-cycle J-T or throttle-cycle refrigerators take advantage of mixed refrigerant gases to achieve low-cost cryocooler systems in the 65 to 80 K temperature range. Tactical Stirling cryocoolers, the mainstay of the defense uidustry, continue to fmd application in cost-constrained commercial applications and space missions; the significant development here is the cost-effective incorporation of Oxford-like flexure spring piston supports so as to achieve an extended-life, low-cost product. The objective of Cryocoolers 13 is to archive these latest developments and performance measurements by drawing upon the work of the leaduig international experts in the field of cryocoolers. In particular, this book is based on their contributions at the 13th International Cryocooler Conference that was held in New Orleans, Louisiana, on March 29 - April 1, 2004. The program of this conference consisted of 123 papers; of these, 88 are published here. Although this is the thirteenth meeting of the conference, which has met every two years since 1980, the authors' works have only been made available to the public ui hardcover book form suice 1994. This book is thus the sixth volume in this new series of hardcover texts on cryocoolers. Because this book is designed to be an archival reference for users of cryocoolers as much as for developers of cryocoolers, extra effort has been made to provide a thorough Subject Index that covers the referenced cryocoolers by type and manufacturer's name, as well as by the scientific or engineering subject matter. Extensive referencing of test and measurement data, and application and integration experience, is included under specific index entries. Contributing organizations are also listed in the Subject Index to assist in finding the work of a known institution, laboratory, or manufacturer. To aide those attempting to locate a particular contributor's work, a separate Author Index is provided, listing all authors and coauthors. Vi PREFACE Prior to 1994, proceedings of the International Cryocooler Conference were published as informal reports by the particular government organization sponsoring the conference — typically a different organization for each conference. A listing of previous conference proceedings is presented ia the Proceedings Index, at the rear of this book. Most of the previous proceedings were printed in limited quantity and are out of print at this time. The content of Cryocoolers 13 is organized into 15 chapters, starting with papers describing the development of a new class of space cryocoolers to provide cooling in the 4-18 K temperature range. The next several chapters address cryocooler technologies organized by type of cooler, starting with regenerative coolers; these include Stirling cryocoolers, pulse tube cryocoolers, Gifford- McMahon cryocoolers, thermoacoustic refrigerators, and associated regenerator research. Next, recuperative cryocoolers including Joule-Thomson, and sorption cryocoolers are cov­ ered. The technology-specific chapters end with a chapter on unique sub-Kelvin, magnetic, and optical refrigerators. The last three chapters of the book deal with cryocooler integration tech­ nologies and experience to date in a number of representative space and conmiercial applications. The articles in these last three chapters contain a wealth of information for the potential user of cryocoolers, as well as for the developer. It is hoped that this book will serve as a valuable source of reference to all those faced with the challenges of taking advantage of the enabling physics of cryogenics temperatures. The expanding availability of low-cost, reliable cryocoolers is making major advances in a number of fields.

Ronald G. Ross, Jr. Jet Propulsion Laboratory California Institute of Technology Acknowledgments

The International Cryocooler Conference Board wishes to express its deepest appreciation to the Conference Organizing Committee, whose members dedicated many hours to organizing and managing the conduct of the Conference, and wishes to express its appreciation to Lockheed Martin for its financial contribution. Members of the Organizing Committee of the 13th ICC included:

CONFERENCE CO-CHAIRS PROGRAM CHAIRMAN John Hendricks, ACE Eric Marquardt, Ball Aerospace Louis Salerno, NASA/ARC PROGRAM COMMITTEE CONFERENCE ADMINISTRATOR Stuart Banl

In addition to the Committee and Board, key staff personnel made invaluable contributions to the preparations and conduct of the conference. Special recognition is due Laurie Huget, Execu­ tive Director of the Cryogenic Society of America, who managed the registration activities.

VII Contents

Space Cryocoolers for 4-18 K Applications 1

Ball Aerospace 4-10 K Space Cryocoolers 1 D. Glaister, W. Gully, R. Stack, E. Marquardt, Ball Aerospace, Boulder, CO; R. Ross, NASA/JPL, Pasadena, CA

NGST Advanced Cryocooler Technology Development Program (ACTDP) Cooler System 9 J. Raab, R. Colbert, D. Harvey, M. Michaelian, T. Nguyen, M. Petach, R. Orsini, E. Tward, M. Waterman, NGST, Redondo Beach, CA

A Study of the Use of 6K ACTDP Cryocoolers for the MIRI Instrument on JWST 15 RG. Ross, Jr., NASA/Jet Propulsion Laboratory, Pasadena, CA

Lockheed Martin 6K/18K Cryocooler 25 J. Olson, P. Champagne, E. Roth, B. Evtimov, R. Clappier, T. Nast, Lockheed Martin ATC Palo Alto, CA; T. Renna, B. Martin, Lockheed Martin CSS, Newtown, PA

Status of Pulse Tube Cryocooler Development at Sunpower 31 K. Wilson, Sunpower, Inc., Athens, OH; D. Gedeon, Gedeon Assoc, Athens OH

Development of a Small-Scale Collins-Type lOK Cryocooler for Space Applications 41 C. Hannon, B. Krass, J. Gerstmann, Advanced Mechanical Technology, Inc., Watertown, MA; G. Chaudhry, J. Brisson, J. Smith, MIT, Cambridge, MA

20 to 80 K Long-life Stirling Cryocoolers 51

STI's Solution for High Quality Production of Stirling Coolers 51 A. O'Baid, A. Fiedler, A. Karandikar, STI, Santa Barbara, CA

Raytheon RSI Cryocooler Performance 59 M.C Barr, KX>. Price, GJ{. Pruitt, Raytheon, El Segundo, CA

Ball Aerospace Next Generation 2-Stage 35 K SB235 Coolers 65 E. Marquardt, W. Gully, D. Glaister, R. Stack, Ball Aerospace, Boulder, CO; N. Abhyankar, E. Oliver, AFRL, Kirtland AFB, NM

Development of the LSF95xx 2nd Generation Flexure Bearing Coolers 71 J. Mullie, P. Bruins, T. Benschop, M. Meijers, Thales Cryogenics, The Netherlands

CMC One-Watt Linear Cooler Performance Map at Higher Input Power 77 D. Kuo, M. Schmitt, CMC Electronics Cincinnati, Pasadena, CA

ix X CONTENTS Space Pulse Tube Cryocooler Developments 85

Characterization of the NGST 150 K Mini Pulse Tube Cryocooler 85 N. Abhyankar, Dynacs, Inc., Albuquerque, NM; T. Davis, AFRL, Kirtland AFB, NM; D. Curran, Aerospace Corp., El Segundo, CA

Performance Test Results of a Miniature 50 to 80 K Pulse Tube Cooler 93 T. Trollier, A. Ravex, Air Liquide DTA, France; I. Charles, L. Duband, CEA-SBT, France; J. Muttie, P. Bruins, T. Benschop, Tholes Cryogenics, The Netherlands; M. Under, ESA/ESTEQ The Netherlands

Performance of Japanese Pulse Tube Coolers for Space Applications 101 A. Kushino, H. Sugita, Y. Matsubara, JAXA, Japan

High Capacity Staged Pulse Tube 109 C. Jaco, T. Nguyen, D. Harvey, E. Tward, NGST, Redondo Beach, CA

Lockheed Martin RAMOS Engineering Model Cryocooler 115 D. Frank, E. Roth, P. Champagne, J. Olson, B. Evtimov, R. Clappier, T. Nast, Lockheed Martin ATC, Palo Alto, CA; T. Renna, B. Martin, Lockheed Martin CSS, Newtown, PA

Lockheed Martin Two-Stage Pulse Tube Cryocooler for GIFTS 121 T. Nast, D. Frank, E. Roth, P. Champagne, J. Olson, B. Evtimov, R. Clappier, Lockheed Martin ATC, Palo Alto, CA; T. Renna, B. Martin, Lockheed Martin CSS, Newtown, PA

Second Generation Raytheon Stirling/Pulse Tube Hybrid Cold Head Design and Performance 127 C. Kirkconnell, K. Price, K. Ciccarelli, J. Harvey, Raytheon, El Segundo, CA

Commercial and Industrial Pulse Tube Cryocoolers 133

Efficient 10 K Pulse Tube Cryocoolers 133 C. Wang, Cryomech, Inc., Syracuse, NY

Development of Stirling-Type Coaxial Pulse Tube Cryocoolers 141 L. Yang, G. Thummes, Univ. of Giessen, Germany

Low Temperature High Frequency Pulse Tube Cooler Using Precooling 149 J. Poncet, I Charles, A. Gauthier, CEA-SBT, Grenoble, France; T. Trollier, Air Liquide DTA, Sassenage, France

Development of a Single Stage Pulse Tube Refrigerator with Linear Compressor 157 /. Yuan, J. Maquire, American Superconducting Co., Westborough, MA

A Commercial Pulse Tube Cryocooler with 200 W Refrigeration at 80 K .... 165 J. Zia, Praxair, Inc., Tonawanda, NY

Large Scale Cryocooler Development for Superconducting Electric Power AppUcations (HTS-4) 173 A'. Lynch, Praxair, Inc., Tonawanda, NY

The Effect of Mean Pressure on Large Pulse TVibe Cryocoolers 177 N. Lynch, Praxair, Inc., Tonawanda, NY CONTENTS Xi Thermoacoustically-Driven Pulse Tube Cryocoolers 181

operation of Thermoacoustic Stirling Heat Engine Driven Large Multiple Pulse Tlibe Refrigerators 181 B. Arman, J. Wollan, V. Kutsubo, Praxair, Inc. Tonawanda, NY; S. Backhaus, G. Swift, Los Alamos Nat'l Lab, Los Alamos, NM

A Traveling Wave Thermoacoustic Refrigerator within Room Temperature Range 189 Y. Huang, E. Luo, W. Dai, Z. Wu, Chinese Academy of Sciences, Beijing, China

Building a High-Efficiency and Compact-Sized Thermoacoustically- Driven Pulse Tube Cooler 195 W. Dai, E. Luo, Y. Zhou, J. Wu, W. Zhu, Chinese Academy of Sciences, Beijing, China

Linear Compressor Development and Modeling 201

Development of a Linear Compressor for Use in G-M Cryocoolers 201 /. Corey, E. James, CFIC-Qdrive, Troy, NY; A. Kashani, B. Helvensteijn, Atlas Scientific, San Jose, CA; G. Rhoads, AFRL, Wright-Patterson AFB, OH

Compression Losses in Cryocoolers 209 /. Reed, G. Davey, M. Dadd, P. Bailey, Oxford Univ., England

A Novel Method for Controlling Piston Drift in Devices with Clearance Seals 215 P. Spoor J. Corey, CFIC, Troy, NY

Verification of Long Life Operation through Real Time Dynamic Alignment Tracking 225 W Gully, E. Marquardt, D. Glaister, Ball Aerospace, Boulder, CO; N Abhyankar, Dynacs, Albuquerque, NM; and T. Davis, AFRL, Kirtland AFB, NM

Sensorless Balancing of a Dual-Piston Linear Compressor of a Stirling Cryogenic Cooler 231 V. Dubrovsky, Loughborough Univ., England; A. Veprik, N. Pundak, Ricor Ltd., Israel

Dynamically Counterbalanced Single-Piston Linear Compressor of a Cryogenic Cryocooler 241 A. Veprik, I. Nachman, N. Pundak, Ricor Ltd., Israel

Pulse Tube Analysis and Experimental Measurements 251

Counterflow Pulse-Tube Refrigerator 251 M. Will, A. de Waele, Dept. of Applied Physics, Eindhoven Univ. of Tech., The Netherlatids

A Study of Performance Improvement of the Coaxial Inertance Tube Pulse Tube Cryocooler 261 S. Park, Y. Hong, H. Kim, Korea Inst.of Machinery & Materials, Taejeon, Korea; Y. Kim, Pusan Nat'l Univ., Korea

Measurements of Phase Shifts in Inertance Tubes 267 M. Lewis, P. Bradley, R. Radebaugh, NIST, Boulder, CO; E. Luo, Chinese Academy of Sciences, Beijing, China xii CONTENTS Phase Shift and Compressible Fluid Dynamics in Inertance Tubes 275 B. Flake, AFRL, Kirtland AFB, NM; A. Razani, Univ. of New Mexico, Albuquerque, NM

CFD Simulation of Multi-Dimensional Effects in an Inertance Tube Pulse Tube Cryocooler 285 /. Cha, S. Ghiaasiaan, P. Desai, Georgia Inst, of Tech., Atlanta GA; J. Harvey, C. Kirkconnell, Raytheon, El Segundo, CA

Phase Angle Model for Pulse Tube with Secondary Orifice Using Lumped-Element Electrical Network Analysis 293 C. Nguyen, M. Haberbusch, A. Yeckley, Sierra Lobo, Milan, OH

Numerical Simulations of Fluid Flow and Heat Transfer in Pulse Tubes 303 A. Schroth, M. Sahimi, USC, Los Angeles, CA; C. Kirkconnell, Raytheon, El Segundo, CA

Visualization of Secondary Flow in Tapered Double-Inlet Pulse Tube Refrigerators 313 M. Shiraishi, M. Murakami, A. Nakano, AIST, Tsukuba, Japan

Numeric Code for the Design of Pulse Tube Coolers 323 A. Hofmann, Forschungszentrum Karlsruhe, Germany

Enthalpy, Entropy and Exergy Flows in Ideal Pulse Tube Cryocoolers 333 R Kittel, NASA/ARC Moffett Field, CA

Enthalpy, Entropy and Exergy Flow Losses in Pulse Tube Cryocoolers 343 R Kittel, NASA/ARC, Moffett Field, CA

A Model for Energy and Exergy Flow in an Orifice Pulse Tube Refrigerator 353 A. Razani, C. Dodson, UNM, Albuquerque, NM; N. Abhyankar, Dynacs, Albuquerque, NM; B. Flake, AFRL Kirtland AFB, NM

Regenerator Materials Development and Testing 363

Development of New Cryocooler Regenerator Materials—Ductile Intermetallic Compounds 363 K. Gschneidner, A. Pecharsky, V. Pecharsky, Ames Lab, Iowa State Univ., Ames, lA

Status of the Development of Ceramic Regenerator Materials 373 T. Numazawa, K. Kamiya, Tsukuba Magnet Lab; T. Satoh, Sumitomo Heavy Indus.; H Nozawa, T Yanagitani, Konoshima Chem. Co, Japan

Doped AMnOj Perovskites Suitable for Use in Magnetic Cooling Devices .... 381 A. Chemyshov, M. Ilyn, A. Tishin, O. Gorbenko, V. Amelichev, S. Mudretsova, A. Mairova, Moscow State Univ.; Y. Spichkin, Advanced Magnetic Tech. and Consulting, Moscow, Russia

Improved Cooling Power by Means of a Regenerator Made from Lead Wire Mesh 389 A. Waldauf, T. Kottig, S. Moldenhauer, M. Thiirk, P. Seidel, Friedrich-Schiller Univ., Jena, Germany

A Low Porosity Regenerator Matrix for High Frequency Low Temperature Cryocoolers 395 D. Ladner, J. Martin, P. Thompson, Equinox Intersciences, Wheatridge, CO CONTENTS xiii X-Ray Lithography Fabricated MicroChannel Regenerators for Cryocoolers 405 DJ. Guidry, J.T. Parker, A. McCandless, S. Motakef, K. Kelly, Inter. Mezzo Tech., Baton Rouge, LA

Performance Investigation of Stirling-Type Nonmagnetic and Nonmetallic Pulse Tube Cryocoolers for High-Tc SQUID Operation 411 H. Dang, Y. Zhou, J. Liang, Chinese Academy of Sciences, Beijing, China; Y. Ju, Nevis Laboratory, Columbia Univ., New York, NY

Regenerator Modeling and Performance Investigations 421

Flow Circulations in Foil-Type Regenerators Produced by Non- Uniform Layer Spacing 421 D. Gedeon, Gedeon Assoc, Athens, OH

A New Angle of View for Understanding and Evaluating Flow Characteristics of Cyclic Regenerators 431 E. Luo, Chinese Acad, of Sciences, Beijing, China

Experimental Flow Characteristics Study of a High Frequency Pulse Tube Regenerator 439 X. Wang, M. Zhao, H. Cai, J. Liang, Chinese Academy of Science, Beijing, China

Regenerator Flows Modeled Using the Method of Characteristics 445 T. Roberts, AFRL, Kirtland AFB, NM; R Desai, Georgia Inst of Tech., Atlanta, GA

A Fast and Accurate Regenerator Numerical Model 455 / Harvey, C. Kirkconnell, Raytheon, El Segundo, CA; P. Desai, Georgia Inst, of Tech., Atlanta, GA

A Parametric Optimization of a Single Stage Regenerator Using REGEN 3.2 463 /. Shi, J. Pfotenhauer, G. Nellis, Univ. of Wisconsin, Madison, WI

A Numerical Model of an Active Magnetic Regenerator Refrigeration System 471 K. Engelbrecht, G. Nellis, S. Klein, Univ. of Wisconsin, Madison, WI

J-T and Throttle-Cycle Cryocooler Developments 481

Comparative Performance of Throttle Cycle Cryotiger Coolers Operating with Different Mixed Refrigerants 481 M. Boiarski, O. Podtcherniaev, K. Flynn, IGC Polycold Systems, Petaluma, CA

Progress in Micro Joule-Thomson Cooling at Twente University 489 P. Lerou, H. Jansen, G. Venhorst, J. Burger, T. Veenstra, H. Holland, H. ter Brake, M. Elwenspoek, H. Rogalla, Univ. of Twente, The Netherlands

The Performance of Joule Thomson Refrigerator 497 Y. Hong, S. Park, H. Kim, Korea Inst, of Machinery & Materials; Y. Choi, Korea Univ., Seoul, Korea xiv CONTENTS Sorption Cryocooler Developments 503

Development of a 4 K Sorption Cooler for ESA's Darwin Mission: System-Level Design Considerations 503 J. Burger, HJM. ter Brake, H. Holland, G. Venhorst, E. Hondebrink, R. Meijer, T. Veenstra, H. Rogalla, Univ. of Twente, The Netherlands; M. Coesel, Dutch Space, The Netherlands: D. Lozano-Castello, Univ. of Alicante, Spain; A. Sirbi, ESA-ESTEC, The Netherlands

Improvements in Sorption Compressor Design 513 G. Wiegerinck, J. Burger, H. Holland, E. Hondebrink, H. ter Brake, H. Rogalla, Univ. of Twente, The Netherlands

Cryogenic Testing of Planck Sorption Cooler Test Facility 523 B. Zhang, D. Pearson, J. Borders, M. Prina, J. Hardy NASA/JPL, Pasadena, CA; D. Crumb, Swales Aerospace, Pasadena, CA

Sub-Kelvin, Magnetic, and Optical Refrigerators 533

Cryogenic Tests of a 0.1 K Dilution Cooler for Planck HFI 533 L. Sentis, J. Delmas, Air Liquide DTA, France; P. Camus, CNRS/CRTBT, Grenoble, France: G. Guyot, CNRS/IAS, Orsay, France; Y. Blanc, CNES, Toulouse, France

Herschel Sorption Cooler Qualification Models 543 L. Duband, L. Clerc, L. Guillemet, R. Vallcorba CEA-SBT, France

ADR Configurations an Optimization for Cryocooler-Based Operation 553 P Shirron, M. DiPirro, J. Tuttle, E. Canavan, NASA/GSFC, Greenbelt, MD

Small Adiabatic Demagnetization Refrigerator for Space Missions 561 N. Luchier, CEA-SBT, Grenoble, France

Magnetoresistive Heat Switches and Compact Superconducting Magnets for a Miniature Adiabatic Demagnetization Refrigerator 567 J. Duval, B. Cain, P. Timbie, Dept. of Physics, Univ. of Wisconsin, Madison, WI

The Performance of a Laboratory Optical Refrigerator 575 G. Mills, D. Glaister, W. Good, A. Mord, Ball Aerospace, Boulder, CO

Cryocooler Integration Technologies 583

A Thermal Storage Unit for Low Temperature Cryocoolers 583 R. Levenduski, J. Lester, Redstone Aerospace, Longmont, CO

Development of a Nitrogen Thermosiphon for Remote Cryogenic Devices 593 /. Yuan, J. Maquire, American Superconductor Co., Westborough, MA

Space Cryocooler Applications 599

Long Life Cryocoolers for Space Applications, A Database Update 599 T Davis, AFRL, Kirtland AFB, NM; N Abhyankar, Dynacs Inc., Albuquerque, NM

Active Versus Standby Redundancy for Improved Cryocooler Reliability in Space 609 RG. Ross, Jr., NASA /Jet Propulsion Laboratory, Pasadena, CA CONTENTS XV

INTEGRAL Spectrometer Cryostat Design and Performance after 1.5 Years in Orbit 619 R. Briet, F. Serene, CNES, Toulouse, France

Two Year Performance of the RHESSI Cryocooler 629 R. Boyle, NASA/GSFC, Greenbelt, MD

The Nicmos Turbo-Brayton Cryocooler —Two Years in Orbit 633 W. Swift, J. McCormack, M. Zagarola, F. Dolan, H. Sixsmith, Creare, Hanover, NH

Model for Orbit-Induced Temperature Oscillations in a Miniature Pulse Tube Cryocooler, Part 1: Warm End Components 641 D. Ladner, Lockheed Martin SSC, Denver, CO

Model for Orbit-Induced Temperature Oscillations in a Miniature Pulse Tube Cryocooler, Part 2: Cold Head Components 651 D. Ladner, Lockheed Martin SSC, Denver, CO

Cryogenic Tests of a Development Model for the 90 K Freezer for the International Space Station 661 T. Trollier, C. Aubrey, J. Butterworth, S. Martha, Air Liquide DTA, France; A. Seidel, EADS Space and Trans., Germany; L. De Parolis, ESA/ESTEC, The Netherlands

Commercial Cryocooler Applications 671

Comparison of Measurements and Models for a Pulse Tube Refrigerator to Cool Cryo-Surgical Probes 671 F. Bradley, R. Radebaugh, NIST, Boulder, CO; R. Bailey M. Haas, CIMEX Biotech, Covington, LA

Development of a GM-Type Pulse Tube Refrigerator Cooling System for Superconducting Maglev Vehicles 681 Y. Kondo, M. Terai, Y. Nishikawa, O. Sugiyama, Central Japan Railway Co.; T. Inoue, A. Hirano, T. Goto, S. Fujii, Aisin, Seiki; Y. Jizo, T Amano, Mitsubishi Electric Corp., Japan

High-Power Pulse Tube Cryocooler for Liquid Xenon Particle Detectors .... 689 T. Haruyama, K. Kasami, KEK; Y. Matsubara, Nihon Univ.; T. Nishitani, Y. Maruno, Iwatani Industrial Gases Corp., Japan; K. Giboni, E. Aprile, Columbia Univ., New York

Vibration-Free Pulse Tube Cryocooler for Gravitational Wave Detectors, Part I: Vibration-Reduction Method and Measurement 695 T. Tomaru, T Suzuki, T. Haruyama, T. Shintomi, N Sato, A. Yamamoto, KEK, Tsukuba, Japan; Y. Ikushima, R. Li, Sumitomo Heavy Ind., Tokyo, Japan.T. Akutsu, TUchiyama, S. Miyoki, ICRR/Univ. of Tokyo, Japan

Vibration-Free Pulse Tube Cryocooler for Gravitational Wave Detectors, Part II: Cooling Performance and Vibration 703 R. Li, Y Ikushima, T. Koyama, Sumitomo Heavy Ind., Tokyo, Japan; T. Tomaru, T. Suzuki, T. Haruyama, T. Shintomi, A. Yamamoto, KEK, Tsukuba, Japan

Two-Stage Refrigeration for Subcooling Liquid Hydrogen and Oxygen as Densified Propellants 711 / Baik, Florida Solar Energy Center, Cocoa, FL; H. Chang, Nat'l High Magnetic Field Lab, Tallahassee, FL; W. Notardonato, NASA/KSC, Kennedy Space Center, FL xvi CONTENTS Indexes 719

Proceedings Index 719

Author Index 721

Subject Index 723