Publications by authors named "Deqing Fang"
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
Article Synopsis
- - 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.
^{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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- 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.
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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- * 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.
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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- 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.*
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.
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.
View Article and Find Full Text PDFWe 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.
View Article and Find Full Text PDFWe 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.
View Article and Find Full Text PDFWe search for nuclear recoil signals of dark matter models with a light mediator in PandaX-II, a direct detection experiment in the China Jinping underground laboratory. Using data collected in 2016 and 2017 runs, corresponding to a total exposure of 54 ton day, we set upper limits on the zero-momentum dark matter-nucleon cross section. These limits have a strong dependence on the mediator mass when it is comparable to or below the typical momentum transfer.
View Article and Find Full Text PDFWe report a new search for weakly interacting massive particles (WIMPs) using the combined low background data sets acquired in 2016 and 2017 from the PandaX-II experiment in China. The latest data set contains a new exposure of 77.1 live days, with the background reduced to a level of 0.
View Article and Find Full Text PDFWe report new searches for solar axions and galactic axionlike dark matter particles, using the first low-background data from the PandaX-II experiment at China Jinping Underground Laboratory, corresponding to a total exposure of about 2.7×10^{4} kg day. No solar axion or galactic axionlike dark matter particle candidate has been identified.
View Article and Find Full Text PDFNew constraints are presented on the spin-dependent weakly-interacting-massive-particle- (WIMP-)nucleon interaction from the PandaX-II experiment, using a data set corresponding to a total exposure of 3.3×10^{4} kg day. Assuming a standard axial-vector spin-dependent WIMP interaction with ^{129}Xe and ^{131}Xe nuclei, the most stringent upper limits on WIMP-neutron cross sections for WIMPs with masses above 10 GeV/c^{2} are set in all dark matter direct detection experiments.
View Article and Find Full Text PDFWe report the weakly interacting massive particle (WIMP) dark matter search results using the first physics-run data of the PandaX-II 500 kg liquid xenon dual-phase time-projection chamber, operating at the China JinPing underground laboratory. No dark matter candidate is identified above background. In combination with the data set during the commissioning run, with a total exposure of 3.
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