论文标题
TNG XL的GAPS程序：浮肿，温暖的海王星大小的行星和旋转太阳能型星TOI-1422的外部海王星质量候选者
The GAPS Programme at TNG XL: A puffy and warm Neptune-sized planet and an outer Neptune-mass candidate orbiting the solar-type star TOI-1422
论文作者
论文摘要
我们研究了外部候选TOI-1422B，该候选是由苔丝太空望远镜在高应变的G2V恒星TOI-1422（$ v = 10.6 $ mag）周围发现的，其主要目标是确认其行星性质并表征其特性。我们用HARPS-N光谱仪监测TOI-1422已有1。5年，以精确量化其径向速度变化。用Tess光度法共同分析了径向速度测量值，我们还使用Astralux仪器通过高空间分辨率图像检查混合伴侣。我们估计，父恒星的半径和质量为$ r^*= 1.019 _ { - 0.013}^{+0.014} r _ {\ odot} $，$ m^*= 0.981 _ { - 0.065}我们的分析证实了TOI-1422b的行星性质，也表明存在海王星质量行星在更遥远的轨道上，即候选TOI-1422C，在苔丝光曲线中未检测到。内心星球，TOI-1422B，of $ p _ {\ rm b} = 12.9972 \ pm0.0006 $ days，具有平衡温度$ t _ {\ rm eq，b} = 867 \ pm17 $ k。 b} = 3.96^{+0.13} _ { - 0.11} r _ {\ oplus} $，质量为$ m _ {\ rm b} = 9.0^{+2.3} _ {+2.3} _ { - 2.0} _ { - 2.0} m _ {\ oplus} $ and，因此b} = 0.795^{+0.290} _ { - 0.235} $ g cm $^{ - 3} $，可以被视为温暖的海王星大小的行星。与其他类似质量范围的外型外行星相比，TOI-1422b是最夸大的质量，我们希望该星球具有广泛的气态信封，围绕着核心，质量分数约为$ 10 \％-25 \％-25 \％\％\％$占该星球的质量。外部非运输行星候选toi-1422c的轨道周期为$ p _ {\ rm c} = 29.29^{+0.21} _ { - 0.20} $ days，$ days，最低质量，$ m _ {\ rm c}} \ rm c} \ sin { m _ {\ oplus} $，平衡温度为$ t _ {\ rm eq，c} = 661 \ pm13 $ k，因此，如果确认，可以将其视为另一个温暖的海王星。
We investigate the exoplanet candidate TOI-1422b, which was discovered by the TESS space telescope around the high proper-motion G2V star TOI-1422 ($V=10.6$ mag), 155pc away, with the primary goal of confirming its planetary nature and characterising its properties. We monitored TOI-1422 with the HARPS-N spectrograph for 1.5 years to precisely quantify its radial velocity variation. The radial velocity measurements are analyzed jointly with TESS photometry and we also check for blended companions through high-spatial resolution images using the AstraLux instrument. We estimate that the parent star has a radius and a mass of $R^*=1.019_{-0.013}^{+0.014} R_{\odot}$, $M^*=0.981_{-0.065}^{+0.062} M_{\odot}$, respectively. Our analysis confirms the planetary nature of TOI-1422b and also suggests the presence of a Neptune-mass planet on a more distant orbit, the candidate TOI-1422c, which is not detected in TESS light curves. The inner planet, TOI-1422b, orbits on a period $P_{\rm b}=12.9972\pm0.0006$ days and has an equilibrium temperature $T_{\rm eq, b}=867\pm17$ K. With a radius of $R_{\rm b}=3.96^{+0.13}_{-0.11} R_{\oplus}$, a mass of $M_{\rm b}=9.0^{+2.3}_{-2.0} M_{\oplus}$ and, consequently, a density of $ρ_{\rm b}=0.795^{+0.290}_{-0.235}$ g cm$^{-3}$, it can be considered a warm Neptune-size planet. Compared to other exoplanets of similar mass range, TOI-1422b is among the most inflated ones and we expect this planet to have an extensive gaseous envelope that surrounds a core with a mass fraction around $10\%-25\%$ of the total mass of the planet. The outer non-transiting planet candidate, TOI-1422c, has an orbital period of $P_{\rm c}=29.29^{+0.21}_{-0.20}$ days, a minimum mass, $M_{\rm c}\sin{i}$, of $11.1^{+2.6}_{-2.3} M_{\oplus}$, an equilibrium temperature of $T_{\rm eq, c}=661\pm13$ K and, therefore, if confirmed, it could be considered as another warm Neptune.
