Heavy-ion beam heated tantalum and tungsten near melting
Dmitry N. Nikolaev, Alexander A. Fedenev, Alexander D. Fertman, Alexander A. Golubev, Dieter H. H. Hoffmann , Alexander Hug, Bogdan Ionita, Alexey V. Kantsyrev, Andrey V. Khudomyasov, Mikhail I. Kulish, Johannes Ling , Nikolai Markov, Viktor B. Mintsev, Alexey A. Pyalling, Nikolai S. Shilkin, Vladimir Ya. Ternovoi, Vladimir I. Turtikov, Serban Udrea, Dmitry V. Varentsov, Karin Weyrich, Denis S. Yuriev, Lev M. Shestov and Y. Zhao
At the GSI Helmholtzzentrum für Schwerionenforschung GmbH (Darmstadt, Germany) intense focused beams of energetic heavy ions are used to generate high-energy-density states in matter . In recent experiments, initially solid tantalum and tungsten samples (50–90 μm thick foils) were uniformly heated in a quasi-isobaric way by a microsecond ion-beam pulses. The temperature of a sample has been observed by a fast multi-channel optical pyrometer during and after the heating. The isobaric heat capacity of the melted metals as well as the enthalpy of fusion have been obtained from the temperature-enthalpy dependence, calculated from measured temperature-time data. A good measurement statistics has been achieved by carrying out a large number of the same experiments with identical targets. The obtained experimental results for liquid tantalum and tungsten heated up to 5000 K are presented and discussed.
Keywords: melting, tantalum, tungsten, heat capacity, heavy ion beam, high energy density.