The specific heat anomaly of HgBaCaCuO(1223) near Tc

We have measured the specific heat of the HgBaCaCuO(1223) samples in low temperature, and found the specific heat jumps of these samples near Tc. It is different from the other Hg-systems, The temperature range of the phase transition is very wide, Delta Tc is over 30K. The ac susceptibility shows these samples have one phase transition near Tc. This phenomenon probably is introduced by oxygen inhomogeneity in these samples.