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Abstract The Taishan Antineutrino Observatory (TAO or JUNO-TAO) is a satellite experiment of the Jiangmen Underground Neutrino Observatory (JUNO). Located near a reactor of the Taishan Nuclear Power Plant, TAO will measure the reactor antineutrino energy spectrum with an unprecedented energy resolution of $$<2\%$$ < 2 % at 1 MeV. Energy calibration is critical to achieve such a high energy resolution. Using the Automated Calibration Unit (ACU) and the Cable Loop System (CLS), multiple radioactive sources are deployed to various positions in the TAO detector for energy calibration. The residual non-uniformity can be controlled within 0.2%. The energy resolution degradation and energy bias caused by the residual non-uniformity can be controlled within 0.05% and 0.3%, respectively. The uncertainty of the non-linear energy response can be controlled within 0.6% with the radioactive sources of various energies, and could be further improved with cosmogenic $$^{12}{\textrm{B}}$$ 12 B which is produced by the interaction of cosmic muon in the liquid scintillator. The stability of other detector parameters, e.g., the gain of each Silicon Photo-multiplier, will be monitored with an ultraviolet LED calibration system. 

Although nanoscale deformation, such as nanostrain in iron-chalcogenide (FeSe_xTe_1−x, FST) thin films, has attracted attention owing to its enhancement of general superconducting properties, including critical current density (J_c) and critical transition temperature, the development of this technique has proven to be an extremely challenging and complex process thus far. Herein, we successfully fabricated an epitaxial FST thin film with uniformly distributed nanostrain by injection of a trace amount of CeO₂inside an FST matrix using sequential pulsed laser deposition. By means of transmission electron microscopy and geometric phase analysis, we verified that the injection of a trace amount of CeO₂forms nanoscale defects, with a nanostrained region of tensile strain (ε_zz ≅ 0.02) along thec-axis of the FST matrix. This nanostrained FST thin film achieves a remarkableJ_cof 3.5 MA/cm²under a self-field at 6 K and a highly enhancedJ_cunder the entire magnetic field with respect to those of a pristine FST thin film.