The origin of the radiation observed in the region of the supernova remnant RX J1713.7−3946, one of the brightest TeV emitters, has been debated since its discovery. The existence of atomic and molecular clouds in this object supports the idea that part of the GeV gamma-ray emission in this region originates from proton–proton collisions. However, the observed column density of protons derived from observations of the gas cannot explain the whole emission. Yet there could be a fraction of protons contained in fainter structures that have not been detected so far. Here we search for faint objects in the line of sight of RX J1713.7−3946 using the principle of light extinction and the European Space Agency’s Gaia mission Data Release 2 astrometric and photometric data. We reveal and locate with precision a number of dust clouds and note that only one appears to be in the vicinity of RX J1713.7−3946. We estimate the embedded mass to be M_dust = (7.0 ± 0.6) × 10³ M_⊙, which might be big enough to contain the missing protons. Finally, using the fact that the supernova remnant is expected to be located in a dusty environment and that there appears to be only one such structure in the vicinity of RX J1713.7−3946, we set a very precise constraint on the supernova remnant distance, at 1.12 ± 0.01 kpc.

在超新星遗迹 RX J1713.7-3946（最亮的 TeV 发射器之一）区域观察到的辐射的起源自发现以来一直存在争议。该天体中原子和分子云的存在支持了该区域的部分 GeV 伽马射线发射源于质子-质子碰撞的观点。然而，从气体观测中得到的质子柱密度不能解释整个发射。然而，迄今为止尚未检测到的较暗结构中可能包含一小部分质子。在这里，我们使用消光原理和欧洲航天局的 Gaia 任务 Data Release 2 天体测量和光度测量数据在 RX J1713.7−3946 的视线范围内搜索微弱的物体。我们精确地揭示并定位了许多尘埃云，并注意到只有一个似乎在 RX J1713.7−3946 附近。我们估计嵌入的质量为M_尘埃 = (7.0 ± 0.6) × 10 ³  M⊙，可能大到足以容纳丢失的质子_。最后，利用超新星遗迹预计位于尘土飞扬的环境中，并且在 RX J1713.7−3946 附近似乎只有一个这样的结构这一事实，我们对超新星遗迹的距离设置了一个非常精确的约束。 ，在 1.12 ± 0.01 kpc。