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The PandaX-4T liquid xenon detector at the China Jinping Underground Laboratory is used to measure the solar ^{8}B neutrino flux by detecting neutrinos through coherent scattering with xenon nuclei. Data samples requiring the coincidence of scintillation and ionization signals (paired), as well as unpaired ionization-only signals (US2), are selected with energy threshold of approximately 1.1 keV (0.33 keV) nuclear recoil energy. Combining the commissioning run and the first science run of PandaX-4T, a total exposure of 1.20 and 1.04 tonne·year are collected for the paired and US2, respectively. After unblinding, 3 and 332 events are observed with an expectation of 2.8±0.5 and 251±32 background events, for the paired and US2 data, respectively. A combined analysis yields a best-fit ^{8}B neutrino signal of 3.5 (75) events from the paired (US2) data sample, with ∼37% uncertainty, and the background-only hypothesis is disfavored at 2.64σ significance. This gives a solar ^{8}B neutrino flux of (8.4±3.1)×10^{6} cm^{-2} s^{-1}, consistent with the standard solar model prediction. It is also the first indication of solar ^{8}B neutrino "fog" in a dark matter direct detection experiment.
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http://dx.doi.org/10.1103/PhysRevLett.133.191001 | DOI Listing |
Phys Rev Lett
July 2025
The University of Melbourne, School of Physics, Victoria 3010, Australia.
We show that the Deep Underground Neutrino Experiment (DUNE) has the potential to make a precise measurement of the total active flux of ^{8}B solar neutrinos via neutral-current (NC) interactions with argon. This would complement proposed precise measurements of solar-neutrino fluxes in DUNE via charged-current (CC) interactions with argon and mixed CC/NC interactions with electrons. Together, these would enable DUNE to make a Sudbury Neutrino Observatory (SNO)-like comparison of rates and thus to make the most precise measurements of sin^{2}θ_{12} and Δm_{21}^{2} using solar neutrinos.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
February 2025
Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China.
Multi-component copolymerized donors (MCDs) hold great promise for improving both the efficiency and mechanical robustness of flexible organic solar cells (f-OSCs) owing to their facile molecular tunability and advantageous one-pot copolymerization. However, despite the excellent crystallinity imparted by their highly conjugated polymer backbone, MCDs often struggle to retain photovoltaic performance under large external deformations, limiting their applicability in wearable devices. Herein, we developed a novel series of flexible linker-sequential block MCDs (Fs-MCDs), specifically PM6-Cl-b-D18-Cl-BTB, PM6-Cl-b-D18-Cl-BTH, and PM6-Cl-b-D18-Cl-BTD, by precisely incorporating flexible functional groups into the conjugated polymer skeleton.
View Article and Find Full Text PDFPhys Rev Lett
November 2024
Department of Physics, University of California San Diego, La Jolla, California 92093, USA.
Phys Rev Lett
November 2024
School of Physics and Astronomy, Shanghai Jiao Tong University, Key Laboratory for Particle Astrophysics and Cosmology (MoE), Shanghai Key Laboratory for Particle Physics and Cosmology, Shanghai 200240, China.
Phys Rev Lett
June 2024
Department of Physics, Yokohama National University, Yokohama, Kanagawa 240-8501, Japan.