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Negative specific heat in a thermodynamic model of multifragmentation

C. B. Das·S. Das Gupta·A. Z. Mekjiani
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Abstract

We consider a soluble model of multifragmentation which is similar in spirit to many models which have been used to fit intermediate energy heavy ion collision data. In this model $c_v$ is always positive but for finite nuclei $c_p$ can be negative for some temperatures and pressures. Furthermore, negative values of $c_p$ can be obtained in canonical treatment. One does not need to use the microcanonical ensemble. Negative values for $c_p$ can persist for systems as large as 200 paticles but this depends upon parameters used in the model calculation. As expected, negative specific heats are absent in the thermodynamic limit.

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C. B. Das, S. Das Gupta, A. Z. Mekjiani. 2003-05-02. Negative specific heat in a thermodynamic model of multifragmentation. https://doi.org/10.1103/physrevc.68.014607

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