XENON Collaboration2021-04-212021-04-212021XENON Collaboration. "Search for inelastic scattering of WIMP dark matter in XENON1T." <i>Physical Review D,</i> 103, no. 6 (2021) American Physical Society: https://doi.org/10.1103/PhysRevD.103.063028.https://hdl.handle.net/1911/110294We report the results of a search for the inelastic scattering of weakly interacting massive particles (WIMPs) in the XENON1T dark matter experiment. Scattering off 129Xe is the most sensitive probe of inelastic WIMP interactions, with a signature of a 39.6 keV deexcitation photon detected simultaneously with the nuclear recoil. Using an exposure of 0.83 tonne-years, we find no evidence of inelastic WIMP scattering with a significance of more than 2σ. A profile-likelihood ratio analysis is used to set upper limits on the cross section of WIMP-nucleus interactions. We exclude new parameter space for WIMPs heavier than 100 GeV/c2, with the strongest upper limit of 3.3×10−39 cm2 for 130 GeV/c2 WIMPs at 90% confidence level.engPublished by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.Journal articlePhysRevD-103-063028https://doi.org/10.1103/PhysRevD.103.063028