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The dependence of the nuclear temperature on the source neutron-proton ($N/Z$) asymmetry has been experimentally investigated with the light charged particles (LCPs) generated from 13 reaction systems with different $N/Z$ asymmetries, $^{64}\mathrm{Zn}$ on $^{112}\mathrm{Sn}$, and $^{70}\mathrm{Zn}$, $^{64}\mathrm{Ni}$ on $^{112,124}\mathrm{Sn}$, $^{58,64}\mathrm{Ni}$, $^{197}\mathrm{Au}$, and $^{232}\mathrm{Th}$ at 40 MeV/u. A rather weak $N/Z$ asymmetry dependence of the source temperature has been qualitatively inferred from the extracted $N/Z$ asymmetry dependence of the apparent temperature and that of the relative temperature change by the sequential decay effects with the help of the theoretical simulations. Comparing the present result with those from our previous work and other available experimental results, a weak $N/Z$ asymmetry dependence of nuclear temperature is commonly observed in different independent experiments and with different thermometers, except for the result reported by McIntosh et al. [Phys. Lett. B 719, 337 (2013)]. The origin of the difference between the conclusion of the former group and that of McIntosh et al. is addressed, using statistical multifragmentation model (SMM) simulations.

The experimental liquid-gas phase transition signals are examined for the quasiprojectile (QP) reconstructed from the reactions of $^{40}\mathrm{Ar}+^{27}\mathrm{Al}$, $^{48}\mathrm{Ti}$, $^{58}\mathrm{Ni}$ at 47 MeV/nucleon, using measures of caloric curve, multiplicity derivative, moment parameters, and fluctuation of maximum fragment charge number (NVZ). The QP source is reconstructed, using moving source parametrizations on an event-by-event basis. For the determination of the temperature, a quadrupole fluctuation thermometer is used. Deuterons are chosen for the thermometer to minimize the Coulomb and secondary sequential decay effects. A new event-by-event method is proposed for the thermometer to determine the temperature. All measures show a characteristic signature around the temperature $T=9.0\ifmmode\pm\else\textpm\fi{}0.4$ MeV, which may suggest that the QP system goes into the liquid-gas phase transition at ${T}_{c}=8.3\ifmmode\pm\else\textpm\fi{}0.4$ MeV after the Coulomb correction.