Publications by authors named "Chunxu Yu"

Article Synopsis
  • The PandaX-4T detector at the China Jinping Underground Laboratory detects solar ^{8}B neutrinos through coherent scattering with liquid xenon nuclei, focusing on specific energy thresholds for data selection.
  • The experiment analyzed data from both commissioning and initial science runs, observing a total of 3 paired events and 332 unpaired ionization signals, with background events estimated at 2.8±0.5 and 251±32, respectively.
  • The results indicate a solar ^{8}B neutrino flux of (8.4±3.1)×10^{6}  cm^{-2} s^{-1}, aligning with standard solar model predictions, and providing the first signs of solar neutr
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  • - The study discusses the first search for elastic scattering between low-mass dark matter particles (sub-MeV) and electrons, conducted using the PandaX-4T liquid xenon experiment.
  • - These sub-MeV dark matter particles can gain energy through interactions with cosmic-ray electrons, which could be spotted as electron recoil signals in the experiment.
  • - With an exposure of 0.63 tonne·year, the researchers established new limits on the interaction strength between dark matter and electrons across a range of masses from 10 eV/c² to 3 keV/c².
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^{134}Xe is a candidate isotope for neutrinoless double beta decay (0νββ) search. In addition, the two-neutrino case (2νββ) allowed by the standard model of particle physics has not yet been observed. With the 656-kg natural xenon in the fiducial volume of the PandaX-4T detector, which contains 10.

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  • The study introduces a method called STSS that enhances nanopore signals by controlling the length of ssDNA produced through rolling circle amplification using AcyNTP.
  • This technique effectively converts short oligonucleotide targets into longer ssDNAs, which generate stronger translocation currents in nanopore measurements.
  • By labeling the RCA products with tetrahedral structures and isothermal amplicons, the method improves resolution, signal specificity, and expands the range of detectable targets.
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In order to realize portable pathogen diagnostics with easier quantitation, digitization and integration, we develop a ready-to-use electrochemical sensing strategy (Iso-E-Codelock) for real-time detection of isothermal nucleic acid amplification. Bridged by a branched DNA as codelock, the isothermal amplicon is transduced into increased current of an electrochemical probe, holding multiple advantages of high sensitivity, high selectivity, signal-on response, "zero" background and one-pot operation. Through a self-designed portable instrument (BioAlex PHE-T), the detection can be implemented on a multichannel microchip and output real-time amplification curves just like an expensive commercial PCR machine.

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Article Synopsis
  • This study presents findings from the PandaX-4T experiment, focusing on detecting interactions between dark matter and nucleons through a dark mediator.
  • By analyzing low-energy ionization signal data and applying the Migdal effect, the researchers establish the most stringent limits on the cross section for dark matter masses between 30 MeV/c² and 2 GeV/c².
  • The research also challenges a model where a dark photon decays into scalar dark matter pairs, significantly limiting the possible parameters for this thermal relic dark matter scenario.
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We report a search for light dark matter produced through the cascading decay of η mesons, which are created as a result of inelastic collisions between cosmic rays and Earth's atmosphere. We introduce a new and general framework, publicly accessible, designed to address boosted dark matter specifically, with which a full and dedicated simulation including both elastic and quasielastic processes of Earth attenuation effect on the dark matter particles arriving at the detector is performed. In the PandaX-4T commissioning data of 0.

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Article Synopsis
  • * We focused on low-energy events with specific ionization signals, detecting recoil energies ranging from 0.07 to 2.54 keV.
  • * Our results set the strictest limits for dark matter interactions over various mass ranges, most notably getting closer to the predicted interactions from early Universe mechanisms.
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Nucleic acid testing technology has made considerable progress in the last few years. However, there are still many challenges in the clinical application of multiple nucleic acid assays, such as how to ensure accurate results, increase speed and decrease cost. Herein, a three-way junction structure has been introduced to specifically translate analytes of loop-mediated isothermal amplification to a catalytic hairpin assembly.

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A search for interactions from solar ^{8}B neutrinos elastically scattering off xenon nuclei using PandaX-4T commissioning data is reported. The energy threshold of this search is further lowered compared with the previous search for dark matter, with various techniques utilized to suppress the background that emerges from data with the lowered threshold. A blind analysis is performed on the data with an effective exposure of 0.

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Article Synopsis
  • The study focuses on measuring the half-life of two-neutrino double beta decay (DBD), which can help in the search for elusive Majorana neutrinos through neutrinoless double beta decay.
  • Researchers used the PandaX-4T dual-phase Time Projection Chamber (TPC) with 3.7-tonne natural xenon and released data from 94.9 days of physics experiments.
  • The resulting half-life measurement is 2.27 ± 0.03 () ± 0.10 () × 10 years, marking the first DBD half-life measurement with natural xenon and showcasing the effectiveness of a large-scale liquid xenon TPC for rare event searches.*
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We report a search on sub-MeV fermionic dark matter absorbed by electrons with an outgoing active neutrino using the 0.63  tonne year exposure collected by the PandaX-4T liquid xenon experiment. No significant signals are observed over the expected background.

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  • The study examines the absorption of fermionic dark matter by nuclei, which may provide a new way to detect light dark matter with a distinct monoenergetic signal.
  • Researchers analyzed 95.0 days of data from the PandaX-4T commissioning run to look for signals of fermionic dark matter absorption via a neutral current process.
  • They found no significant signal, establishing a minimum limit for the dark matter-nucleon interaction cross section at 1.5×10^{-50}  cm^{2} for a fermionic dark matter mass of 40  MeV/c^{2} with 90% confidence.
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We report a novel search for the cosmic-ray boosted dark matter using the 100  tonne·day full dataset of the PandaX-II detector located at the China Jinping Underground Laboratory. With the extra energy gained from the cosmic rays, sub-GeV dark matter particles can produce visible recoil signals in the detector. The diurnal modulations in rate and energy spectrum are utilized to further enhance the signal sensitivity.

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We report a universal and signal-on HCR based detection platform innovatively coupling the CRISPR-Cas12a system with HCR. By using this CRISPR-HCR pathway, we can detect different targets by only changing the crRNA. The CRISPR-HCR platform coupling with an upstream amplifier can achieve a practical sensitivity as low as ∼aM of ASFV gene in serum.

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We report the first dark matter search results using the commissioning data from PandaX-4T. Using a time projection chamber with 3.7 tonne of liquid xenon target and an exposure of 0.

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We report constraints on light dark matter through its interactions with shell electrons in the PandaX-II liquid xenon detector with a total 46.9  tonnes/day exposure. To effectively search for these very low energy electron recoils, ionization-only signals are selected from the data.

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Purpose: The study is to explore potential features and develop classification models for distinguishing benign and malignant lung lesions based on CT-radiomics features and PET metabolic parameters extracted from PET/CT images.

Materials And Methods: A retrospective study was conducted in baseline 18 F-flurodeoxyglucose positron emission tomography/ computed tomography (18 F-FDG PET/CT) images of 135 patients. The dataset was utilized for feature extraction of CT-radiomics features and PET metabolic parameters based on volume of interest, then went through feature selection and model development with strategy of five-fold cross-validation.

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The Chinese spallation neutron source (CSNS) is a high-performance pulsed neutron source, having 20 neutron beamlines for neutron scattering instruments. The shielding design of these beamlines is usually needed for Monte Carlo (MC) calculation, and the use of variance reduction methods is critical to carrying out an efficient, reliable MC shielding calculation. This paper discusses the source biasing method based on actual source term and geometry model of a CSNS neutron beamline.

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