arXiv subjects

Guanhua Gu

Publications and source records attributed to Guanhua Gu.

3 recordsLinked to original sources

arXiv2026

Hunting for Axions in REactor neutrino COherent scattering Detection Experiment

Nuclear power plants are not only vital sources of clean energy but also powerful facilities for probing new physics beyond the Standard Model. Due to the intense gamma-ray flux and an appropriate energy conditions, they are particularly well-suited for searches of light hypothetical particles such as sub-MeV axions and axion-like particles (ALPs). In this work, we propose to search for the ALPs in the REactor Neutrino COherent scattering Detection Experiment (RECODE), where two low-threshold, high-purity germanium detectors are placed at 11 m (near point) and 22 m (far point) from a 3.4 GW nuclear reactor at Sanmen nuclear power plant. With a 10 kg$\cdot$year exposure, we demonstrate that the expected sensitivities to the ALP couplings to the electrons and photons are competitive with or surpass the available results from the beam-dump experiments. A planned upgrade to 100 kg$\cdot$year will fully cover the so-called {$\it$ cosmological triangle} region, probing unexplored parameter space relevant to axions.

hep-ph↗

arXiv2026

Inelastic from the Other Side: Xenon Excitation Signals in Light of the LZ High-Recoil Event

The LUX-ZEPLIN (LZ) experiment recently reported a single event consistent with a nuclear recoil of $E_{\rm NR}\sim248\pm23\,(\mathrm{stat})\pm23\,(\mathrm{syst})$~keV in an extended-energy search. We study the accompanying inelastic-xenon channel, $χ+\Xe\toχ+\Xe^{*}$, which provides a complementary test of DM interpretations of such high-recoil events. Using the non-relativistic effective-field-theory (NREFT) framework with shell-model nuclear-transition inputs, we compute the inelastic-xenon rates for representative scenarios including inelastic dark matter and accelerated DM populations. We also simulate their S1--S2 responses, with detector modeling validated against public LZ data. The nuclear de-excitation adds an electromagnetic component shifting the signal toward the electronic-recoil band and, in some cases, toward clustered backgrounds from isotopes. We therefore construct a schematic, physics-motivated background model and perform a simplified statistical analysis. For many benchmarks, the inelastic-xenon rate is $\mathcal{O}(0.1)$ of the elastic rate or below, suggesting that substantially larger exposures are required before this companion channel becomes observable. Our results illustrate the importance of isotope-induced background structures in the extended-energy region and extend the phenomenology of inelastic-xenon signatures to a wider range of DM scenarios.

hep-ph↗

arXiv2026

Inelastic Scattering Effects on Attenuation of Boosted Dark Matter

Earth attenuation is crucial for interpreting direct-detection constraints on boosted dark matter (DM), since scatterings with terrestrial nuclei can significantly modify the flux and energy spectrum reaching underground detectors. At boosted energies, inelastic nuclear channels beyond ordinary elastic scattering can become relevant, including quasi-elastic scattering, deep-inelastic scattering, and resonant scattering. In this work, we incorporate the resonant scattering of boosted dark matter (DM) off nuclei into the Earth-attenuation framework, in combination with the elastic, quasi-elastic, and deep-inelastic channels. We find that, in the heavy-mediator regime, resonant scattering can give a non-negligible contribution to the attenuation of boosted DM. Using the latest PandaX-4T data, we derive new constraints on the spin-independent boosted DM-nucleon cross section $\barσ_n$.

hep-ph↗