In the light of the recently observed XENON1T electronic recoil (ER) data, we investigate the possibility of constraining the parameter space of a generic fermionic warm dark matter (WDM), decaying into a standard model (SM) neutrino and a photon. The photon as a decay product, when produced inside the XENON1T chamber, interacts with an electron of a xenon (Xe) atom, leading to a contribution in the observed ER data. We add this dark matter (DM) induced signal over the standard background (${\mathrm{B}}_0$) considered by the XENON1T collaboration and perform a ${\chi }^2$ fit against the XENON1T data to obtain the best-fit values of the DM decay width and the associated 95% confidence level (C.L.) band for DM mass ($m_{\chi }$) varied in the range 2–60 keV. Additionally, we have extended our analysis by including two other background models available in the literature and in each case, the corresponding limits on the DM decay width are estimated for DM mass ($m_{\chi }$) in the domain 2–18 keV. By comparing the constraints, obtained by fitting the XENON1T data, with the upper limits arising from various existing astrophysical and cosmological observations, we find that, for the background model ${\mathrm{B}}_0$, a fair amount of the DM parameter space is allowed at 95% C.L. for DM masses outside the range $3.5\mathrm{keV}\lesssim m_{\chi }\lesssim 8.5\mathrm{keV}$. However, in case of other two background models, reasonable parts of the DM parameter space are favored at 95% C.L. by all astrophysical data for all DM masses in the range 2–18 keV.

根据最近观察到的 XENON1T 电子反冲 (ER) 数据，我们研究了约束通用费米子暖暗物质 (WDM) 参数空间的可能性，衰减为标准模型 (SM) 中微子和光子。作为衰变产物的光子在 XENON1T 室内产生时，会与氙 (Xe) 原子的电子相互作用，从而对观察到的 ER 数据产生影响。我们在标准背景（${\mathrm{乙}}_0$) 由 XENON1T 合作考虑并执行 ${\chi }^2$ 拟合 XENON1T 数据以获得 DM 衰减宽度的最佳拟合值和 DM 质量的相关 95% 置信水平 (CL) 带 (${米}_{\chi }$) 在 2–60 keV 范围内变化。此外，我们通过包括文献中可用的另外两个背景模型来扩展我们的分析，并且在每种情况下，DM 衰减宽度的相应限制是针对 DM 质量估计的（${米}_{\chi }$) 在域 2–18 keV。通过将拟合 XENON1T 数据获得的约束与现有各种天体物理和宇宙学观测产生的上限进行比较，我们发现，对于背景模型${\mathrm{乙}}_0$，对于超出范围的 DM 质量，在 95% CL 下允许有相当数量的 DM 参数空间 $3.5\mathrm{keV}\lesssim {米}_{\chi }\lesssim 8.5\mathrm{keV}$. 然而，在其他两个背景模型的情况下，DM 参数空间的合理部分在 95% CL 时被所有 2-18 keV 范围内的所有 DM 质量的天体物理数据所支持。