Supported by an ERC Starting Grant (project 307270-ATTOSCOPE);
an ERC Consolidator Grant (project 772797-ATTOLIQ); the NCCR-
MUST, a funding instrument of the Swiss National Science Foundation;
an Ambizione grant of the Swiss National Science Foundation (A.S.);
and the European Union’s Horizon 2020 research and innovation
programme under the Marie Skłodowska-Curie grant agreement
no. 801459 - FP-RESOMUS (D.J.).Author contributions:I.J. and M.H.
built the experimental setup and performed the measurements; I.J.
analyzed the data; A.v.C. contributed to the measurements of the
monochromatic photoelectron spectra; D.R., M.P., I.J., and C.P.
contributed to the development of the theoretical model and
calculations; A.S. performed the Monte Carlo trajectory simulations;
D.J. realized the photoionization-delay calculations; and H.J.W.
supervised the project and wrote the manuscript with input from all
coauthors.Competing interests:None to declare.Data and
materials availability:All data needed to evaluate the conclusions in
the paper are present in the paper or the supplementary materials,
as well as online at Zenodo ( 45 ).SUPPLEMENTARY MATERIALS
science.sciencemag.org/content/369/6506/974/suppl/DC1
Materials and Methods
Figs. S1 to S12
Tables S1 and S2
References ( 46 – 59 )
29 January 2020; accepted 10 July 2020
10.1126/science.abb0979Jordanet al.,Science 369 , 974–979 (2020) 21 August 2020 6of6
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