Four-color CCD photometric light curves (LCs) of eclipsing binary (EB) NSVS 11868841 are presented in this paper. These LCs are analyzed by using the 2013 version of the Wilson–Devinney (W–D) code. We found that NSVS 11868841 is a late-type low-mass detached EB with an orbit inclination nearly $90°$. The LCs are asymmetric, especially in its out-of-eclipse. Based on all available times of the light minimum, we analyzed the variations of the orbital period by using the ($O$–$C$) method. The O–C curve shows a cycle oscillation with a period of 11.83($\pm 0.04$) years and an amplitude of 0.0009 days ($\sim$ 1.3 min). This cyclic change detected in NSVS 11868841 could be explained by the light-travel time effect (LTTE) via the presence of a third body. Subsequently, we calculated the mass of this third component as $M_3$sin($i_3$)=0.047($\pm 0.015$)$M_{\odot }$. If the third body is coplanar with the central system, it may be a brown dwarf. And this discovery will provide important insights on the formation and evolution of brown dwarf companions.

本文介绍了食双星 (EB) NSVS 11868841 的四色 CCD 光度曲线 (LC)。这些 LC 使用 2013 版的 Wilson-Devinney (W-D) 代码进行分析。我们发现 NSVS 11868841 是一颗晚型低质量分离 EB，轨道倾角接近$90°$. LC 是不对称的，尤其是在它的日食外。基于光极小值的所有可用时间，我们通过使用（$哦$——$C$） 方法。O-C 曲线显示了一个周期为 11.83($\pm 0.04$) 年，振幅为 0.0009 天 ($～$1.3 分钟）。在 NSVS 11868841 中检测到的这种循环变化可以用光传播时间效应 (LTTE) 通过第三个物体的存在来解释。随后，我们计算了第三个组件的质量为${米}_3$罪（${\mathrm{一世}}_3$)=0.047($\pm 0.015$)${米}_{\odot }$. 如果第三颗天体与中央系统共面，它可能是一颗棕矮星。而这一发现将为褐矮星伴星的形成和演化提供重要的见解。