The authors apologize for the misprints in the article “Improved Generation of Higher Harmonics and Suppression of the Lowest Harmonics in an X-Ray FEL with a Two-Frequency Undulator” by K. Zhukovsky in Moscow University Physics Bulletin, 2018, Vol. 73, No. 5, pp. 462–469, DOI: https://doi.org/10.3103/S0027134918050193, and communicate the following corrected formula (5) for the Bessel coefficients f_n of the two-frequency undulator:

中文翻译：

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勘误到：具有两频波动器的X射线FEL中改进的高次谐波生成和最低的谐波抑制

作者在莫斯科大学物理公告，2018年，第一卷，作者K.Zhukovsky的文章“改进的高次谐波生成和在X射线FEL中用两个频率的波动抑制最小谐波”中的错误印刷道歉。73，第5号，第462–469页，DOI：https：//doi.org/10.3103/S002713491805050193，并传达了针对两频波荡器的贝塞尔系数f _n的以下校正公式（5）：