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An improved thermometer for intermediate-mass fragments


An improved thermometer (T IB) is proposed for intermediate-mass fragments via the difference between isobaric yield ratios. The residual free energy of three isobars is replaced by that of the binding energy. The measured fragments in the 140A MeV 40, 48Ca + 9Be (181Ta) and 58, 64Ni + 9Be (181Ta) reactions are analyzed to obtain T IB ranging from 0.6 to 3.5 MeV. T IB is suggested to be a direct determination of temperature avoiding the fitting procedure.

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Correspondence to Chun-Wang Ma.

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Ding, TT., Ma, CW. An improved thermometer for intermediate-mass fragments. NUCL SCI TECH 27, 132 (2016).

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  • Temperature
  • Intermediate-mass fragment
  • Isobaric ratio