$^{57}$Cu in units of MeV.[]{data-label="fig2"}](fig.2.eps){width="3.2in" height="4.3in"}

The authors in Ref. [@Jokinen02] investigated the beta-delayed proton decay of $^{57}$Zn at GSI online isotope separator. $^{57}$Zn nuclei were produced in fusion evaporation reactions, $^{28}$Si($^{32}$S, 3n), by using a 150 MeV $^{32}$S beam on a $^{28}$Si target and then the beta-delayed protons were measured with high resolution by employing a charged-particle detector. The GT strength distributions observed in this experiment is shown in the middle panel of Fig. \[fig1\]. The morphology of the pn-QRPA GT strength (upper panel) for beta transitions between the ground state of $^{57}$Zn to the ground state of daughter $^{57}$Cu is in good agreement with the measured data of Ref. [@Jokinen02]. These transitions are of allowed nature in daughter $^{57}$Cu. The experimental GT strength between 2 and 3 MeV is well reproduced by pn-QRPA. These peaks were missing in the large-scale shell model calculation as shown in the bottom panel of Fig. \[fig1\]. We used the $Q$-value of 14.51 MeV for $^{57}$Zn from the recent compilations of Ref. [@Audi03a; @Audi03b].

![Comparison of experimental and shell model integrated GT strength within the $Q_{EC}$ window. The figure is reproduced from Ref. [@Jokinen02].[]{data-label="fig3"}](fig.3.eps){width="4.3in" height="4.3in"}

It is evident that the GT strength distribution 