{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T16:20:12Z","timestamp":1791476412008,"version":"4.3.4"},"reference-count":45,"publisher":"AIP Publishing","issue":"4","license":[{"start":{"date-parts":[[2025,7,9]],"date-time":"2025-07-09T00:00:00Z","timestamp":1752019200000},"content-version":"vor","delay-in-days":8,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100010274","name":"Daegu Gyeongbuk Institute of Science and Technology","doi-asserted-by":"publisher","award":["2025010011"],"award-info":[{"award-number":["2025010011"]}],"id":[{"id":"10.13039\/501100010274","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2024-00338014"],"award-info":[{"award-number":["RS-2024-00338014"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2024-00409972"],"award-info":[{"award-number":["RS-2024-00409972"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2025,7,1]]},"abstract":"<jats:p>Time-resolved x-ray liquidography (TRXL) is a powerful technique for directly tracking ultrafast structural dynamics in real space. However, resolving the motion of vibrational wavepackets generated by femtosecond laser pulses remains challenging due to the limited temporal resolution and signal-to-noise ratio (SNR) of experimental data. This study addresses these challenges by introducing singular spectrum analysis (SSA) as an efficient method for extracting oscillatory signals associated with vibrational wavepackets from TRXL data. To evaluate its performance, we conducted a comparative study using simulated TRXL data, demonstrating that SSA outperforms conventional analysis methods such as the Fourier transform of temporal profiles and singular value decomposition, particularly under low SNR conditions. We further applied SSA to experimental TRXL data on the photodissociation of triiodide (I3\u2212) in methanol, successfully isolating oscillatory signals arising from wavepacket dynamics in ground-state I3\u2212 and excited-state I2\u2212, which had been challenging to resolve in previous TRXL studies. These results establish SSA as a highly effective tool for analyzing ultrafast structural dynamics in time-resolved experiments and open new opportunities for studying wavepacket dynamics in a wide range of photoinduced reactions.<\/jats:p>","DOI":"10.1063\/4.0000764","type":"journal-article","created":{"date-parts":[[2025,7,9]],"date-time":"2025-07-09T12:04:26Z","timestamp":1752062666000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":1,"title":["Unveiling hidden wavepacket dynamics in time-resolved x-ray scattering data via singular spectrum analysis"],"prefix":"10.1063","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-3399-6676","authenticated-orcid":false,"given":"Jaeseok","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Physics and Chemistry, Daegu Gyeongbuk Institute of Science and Technology 1 , Daegu 42988,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-1206-6923","authenticated-orcid":false,"given":"Hyunwoo","family":"Jeong","sequence":"additional","affiliation":[{"name":"Department of Physics and Chemistry, Daegu Gyeongbuk Institute of Science and Technology 1 , Daegu 42988,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8186-0226","authenticated-orcid":false,"given":"Jae Hyuk","family":"Lee","sequence":"additional","affiliation":[{"name":"Pohang Accelerator Laboratory 2 , POSTECH, Pohang 37673,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2555-618X","authenticated-orcid":false,"given":"Rory","family":"Ma","sequence":"additional","affiliation":[{"name":"Pohang Accelerator Laboratory 2 , POSTECH, Pohang 37673,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daewoong","family":"Nam","sequence":"additional","affiliation":[{"name":"Pohang Accelerator Laboratory 2 , POSTECH, Pohang 37673,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2504-1314","authenticated-orcid":false,"given":"Minseok","family":"Kim","sequence":"additional","affiliation":[{"name":"Pohang Accelerator Laboratory 2 , POSTECH, Pohang 37673,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1277-5279","authenticated-orcid":false,"given":"Dogeun","family":"Jang","sequence":"additional","affiliation":[{"name":"Pohang Accelerator Laboratory 2 , POSTECH, Pohang 37673,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9267-7697","authenticated-orcid":false,"given":"Jong Goo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Physics and Chemistry, Daegu Gyeongbuk Institute of Science and Technology 1 , Daegu 42988,","place":["Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2025,7,9]]},"reference":[{"key":"2025070917512623900_c1","doi-asserted-by":"publisher","first-page":"297","DOI":"10.1016\/0009-2614(89)85088-2","article-title":"Femtosecond transition-state spectroscopy of iodine: From strongly bound to repulsive surface dynamics","volume":"161","year":"1989","journal-title":"Chem. 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