We have studied the alpha-decay (AD) and spontaneous fission (SF) properties of the isotopes of Z=125, 126 and 127 superheavy nuclei. AD calculations have been performed over all the possible isotopes of Z=125-127 nuclei within the framework of Wentzel-Kramers-Brillouin (WKB) and Bohr-Sommerfeld quantization condition. To broaden the perspective of the calculations, we have also utilized from the analytic formula of Royer in the calculations of AD. In this way we believe that by using various approaches might be useful for the clarity of the predictions. Also, the SF half-lives have been computed by using formulae of Soylu and KPS. Decay modes for the isotopes are determined by using the results of different models. The decay modes obtained for Z=125 and Z=126 have been compared with the results of other studies, and α-decay chains have been presented for Z=127. Findings would provide opportunities for the future experimental researches.

我们研究了Z = 125、126和127超重核同位素的α衰变（AD）和自发裂变（SF）特性。在Wentzel-Kramers-Brillouin（WKB）和Bohr-Sommerfeld量化条件的框架内，已对Z = 125-127原子核的所有可能同位素进行了AD计算。为了拓宽计算的视野，我们还从Royer的解析公式中利用了AD的计算。通过这种方式，我们相信通过使用各种方法可能对预测的清晰性很有用。而且，SF的半衰期已通过使用Soylu和KPS的公式进行了计算。同位素的衰变模式是通过使用不同模型的结果确定的。将Z = 125和Z = 126时获得的衰减模式与其他研究的结果进行了比较，α-衰变链已经提出，Z ＝ 127。这些发现将为未来的实验研究提供机会。