Validity of extracting photoionization time delay from the first moment of streaking spectrogram<xref rid="cpb_28_1_013201fn1" ref-type="fn">*</xref><fn id="cpb_28_1_013201fn1"><label>*</label><p>Project supported by the Talent Introduction Foundation of Qiannan Normal University of Nationalities, China (Grant No. qnsyrc201619), Natural Science Foundation of Guizhou Provincial Education Department for Young Talents, China (Grant No. Qian Education Contract KY[2017]339), and Chemical Sciences, Geosciences and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy (Grant No. DE-FG02-86ER13491).</p></fn>

Validity of extracting photoionization time delay from the first moment of streaking spectrogram**

Project supported by the Talent Introduction Foundation of Qiannan Normal University of Nationalities, China (Grant No. qnsyrc201619), Natural Science Foundation of Guizhou Provincial Education Department for Young Talents, China (Grant No. Qian Education Contract KY[2017]339), and Chemical Sciences, Geosciences and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy (Grant No. DE-FG02-86ER13491).

Wei Chang-Li¹, Zhao Xi^{2, †}

The group delay dispersion corresponding to the Wigner part GDD^dip(Ω) = dτ^dip(Ω)/dΩ and to the CLC part GDD^CLC(Ω) = dτ^CLC(Ω)/dΩ, for both Ne and Ar.