Miniature Joule Thomson Cryocooling : Principles and Practice This book is the first in English being entirely dedicated to Miniature Joule Thomson Cryocooling. The category of Joule Thomson (JT) cryocoolers takes us back to the roots of cryogenics in 1895 with figures like Linde and Hampson. The cold finger of these cryocoolers is compact lacks moving parts and sustains a large heat flux extraction at a steady temperature. Potentially they cool down unbeatably fast. For example cooling to below 100 K (minus 173 Celsius) might be accomplished within only a few seconds by liquefying argon. A level of about 120 K can be reached almost instantly with krypton. Indeed the species of coolant plays a central role dictating the size the intensity and the level of cryocooling. It is the JT effect that drives these cryocoolers and reflects the deviation of the real gas from the ideal gas properties. The nine chapters of the book are arranged in five parts. The Common Principle of Cyrocoolers shared across the broad variety of cryocooler types Theoretical Aspects: the JT effect and its inversion cooling potential of coolants the liquefaction process sizing of heat exchangers level of pressurization discharge of pressure vessels Practical Aspects: modes of operation (fast cooldown continuous multi staging hybrid cryocoolers) pressure sources configuration construction and technologies flow adjustment MEMS open and closed cycle cooldown process and similarity transient behavior Mixed Coolant cryocooling: theory practice and applications Special Topics: real gas choked flow rates gas purity clog formation optimal fixed orifice modeling cryosurgical devices warming by the inverse JT effect The theoretical aspects may be of interest not only to those working with cryocoolers but also for others with a general interest in real gas thermodynamics such as for example the inversion of the JT effect in its differential and integral forms and the exceptional behavior of the quantum gases. A detailed list of references for each chapter comprises a broad literature survey. It consists of more than 1 200 relevant publications and 450 related patents. The systematically organized content arranged under a thorough hierarchy of headings supported by 227 figures and 41 tables and accompanied by various chronological notes of evolution enables readers a friendly interaction with the book. Dr. Ben Zion Maytal is a Senior Researcher at Rafael Advanced Defense Systems Ltd. and an Adjunct Senior Teaching Fellow at the Technion Israel Institute of Technology Haifa Israel. Prof. John M. Pfotenhauer holds a joint appointment in the Departments of Mechanical Engineering and Engineering Physics at the University of Wisconsin Madison.