To put the Solar System’s terrestrial planets in context, the detection and characterization of low-mass exoplanets is important but challenging. The Dispersed Matter Planet Project targets stars with anomalously low Ca ii H and K chromospheric emission, indicative of circumstellar absorbing gas. Here we report high-precision, high-cadence radial-velocity measurements of the F8V star DMPP-1 (HD 38677). These were motivated by depressed Ca ii H and K line cores indicative of short-period, ablating planets producing circumstellar gas. We find a compact planetary system with orbital periods of about 2.9–19 days, comprising three super-Earth-mass planets (about 3–10 M_⊕) and one Neptune-mass planet (about 24 M_⊕). The irradiated super-Earths may be remnant cores of giant planets after mass loss while crossing the Neptune desert. A priori inferences about the presence of short-period planets enabled the efficient discovery of the DMPP-1 planets. We anticipate informative follow-up characterization studies.

为了将太阳系的地球行星置于背景中，低质量系外行星的检测和表征很重要，但具有挑战性。“分散物质星球”项目的目标是在Ca ii H和K色球层发射异常低的恒星 ，这表明了星吸收气体。在这里，我们报告了F8V星型DMPP-1（HD 38677）的高精度，高节奏径向速度测量。这些是由凹陷的Ca ii H和K线芯引起的，这些 芯线指示短时消融的行星产生了星际气体。我们发现一个紧凑的行星系统，其轨道周期约为2.9–19天，包括三个超地球质量行星（约3–10 _M⊕）和一个海王星质量行星（约24 _M⊕）。）。辐射的超地球可能是穿越海王星沙漠的质量损失后留下的巨型行星的核心。对短周期行星的存在的先验推论使得能够有效地发现DMPP-1行星。我们期待提供内容丰富的后续特征研究。