SPHERE+: Imaging young Jupiters down to the snowline
A. Boccaletti, G. Chauvin, D. Mouillet, O. Absil, F. Allard, S. Antoniucci, J. -C. Augereau, P. Barge, A. Baruffolo, J. -L. Baudino, P. Baudoz, M. Beaulieu, M. … 展开作者
A. Boccaletti, G. Chauvin, D. Mouillet, O. Absil, F. Allard, S. Antoniucci, J. -C. Augereau, P. Barge, A. Baruffolo, J. -L. Baudino, P. Baudoz, M. Beaulieu, M. Benisty, J. -L. Beuzit, A. Bianco, B. Biller, B. Bonavita, M. Bonnefoy, S. Bos, J. -C. Bouret, W. Brandner, N. Buchschache, B. Carry, F. Cantalloube, E. Cascone, A. Carlotti, B. Charnay, A. Chiavassa, E. Choquet, Y. Clenet, A. Crida, J. De Boer, V. De Caprio, S. Desidera, J. -M. Desert, J. -B. Delisle, P. Delorme, K. Dohlen, D. Doelman, C. Dominik, V. D Orazi, C. Dougados, S. Doute, D. Fedele, M. Feldt, F. Ferreira, C. Fontanive, T. Fusco, R. Galicher, A. Garufi, E. Gendron, A. Ghedina, C. Ginski, J. -F. Gonzalez, D. Gratadour, R. Gratton, T. Guillot, S. Haffert, J. Hagelberg, T. Henning, E. Huby, M. Janson, I. Kamp, C. Keller, M. Kenworthy, P. Kervella, Q. Kral, J. Kuhn, E. Lagadec, G. Laibe, M. Langlois, A. -M. Lagrange, R. Launhardt, L. Leboulleux, H. Le Coroller, G. Li Causi, M. Loupias, A. L. Maire, G. Marleau, F. Martinache, P. Martinez, D. Mary, M. Mattioli, J. Mazoyer, H. Meheut, F. Menard, D. Mesa, N. Meunier, Y. Miguel, J. Milli, M. Min, P. Molliere, C. Mordasini, G. Moretto, L. Mugnier, G. Muro Arena, N. Nardetto, M. N Diaye, N. Nesvadba, F. Pedichini, P. Pinilla, E. Por, A. Potier, S. Quanz, J. Rameau, R. Roelfsema, D. Rouan, E. Rigliaco, B. Salasnich, M. Samland, J. -F. Sauvage, H. -M. Schmid, D. Segransan, I. Snellen, F. Snik, F. Soulez, E. Stadler, D. Stam, M. Tallon, P. Thebault, E. Thiebaut, C. Tschudi, S. Udry, R. van Holstein, P. Vernazza, F. Vidal, A. Vigan, R. Waters, F. Wildi, M. Willson, A. Zanutta, A. Zavagno, A. Zurlo
SPHERE (Beuzit et al,. 2019) has now been in operation at the VLT for more than 5 years, demonstrating a high level of performance. SPHERE has produced outstanding results using a variety of operating modes, primarily in the field of direct imaging of exoplanetary systems, focusing on exoplanets as point sources and circumstellar disks as extended objects. The achievements obtained thus far with SPHERE (~200 refereed publications) in different areas (exoplanets, disks, solar system, stellar physics...) have motivated a large consortium to propose an even more ambitious set of science cases, and its corresponding technical implementation in the form of an upgrade. The SPHERE+ project capitalizes on the expertise and lessons learned from SPHERE to push high contrast imaging performance to its limits on the VLT 8m-telescope. The scientific program of SPHERE+ described in this document will open a new and compelling scientific window for the upcoming decade in strong synergy with ground-based facilities (VLT/I, ELT, ALMA, and SKA) and space missions (Gaia, JWST, PLATO and WFIRST). While SPHERE has sampled the outer parts of planetary systems beyond a few tens of AU, SPHERE+ will dig into the inner regions around stars to reveal and characterize by mean of spectroscopy the giant planet population down to the snow line. Building on SPHERE's scientific heritage and resounding success, SPHERE+ will be a dedicated survey instrument which will strengthen the leadership of ESO and the European community in the very competitive field of direct imaging of exoplanetary systems. With enhanced capabilities, it will enable an even broader diversity of science cases including the study of the solar system, the birth and death of stars and the exploration of the inner regions of active galactic nuclei.
The radial-dependent positions of snowlines of abundant oxygen- and carbon-bearing molecules in protoplanetary discs will result in systematic radial variations in the C/O ratios in the gas and ice. This variation is proposed as a tracer of the formation location of gas-giant planets. However, disc chemistry can affect the C/O ratios in the gas and ice, thus potentially erasing the chemical fingerprint of snowlines in gas-giant atmospheres. We calculate the molecular composition of hot Jupiter atmospheres using elemental abundances extracted from a chemical kinetics model of a disc midplane wh…
The water snowline in circumstellar disks is a crucial component in planet formation, but direct observational constraints on its location remain sparse due to the difficulty of observing water in both young embedded and mature protoplanetary disks. Chemical imaging provides an alternative route to locate the snowline, and HCO$^+$ isotopologues have been shown to be good tracers in protostellar envelopes and Herbig disks. Here we present $\sim$0.5$^{\prime\prime}$ resolution ($\sim$35 au radius) Atacama Large Millimeter/submillimeter Array (ALMA) observations of HCO$^+$ $J=4-3$ and H$^{13}$CO$…
Jupiter's enhancement in nitrogen relative to hydrogen when compared to the Sun has been interpreted as evidence that its early formation occurred beyond the N$_{2}$ snowline ($\sim$ 20-40 AU). However, the rapid growth necessary to form Jupiter before the dissipation of the solar nebula would lead to the forming planet's core reaching very high temperatures ($>$1000 K), which would lead to it warming its surroundings. Here, we explore the effects of a luminous planetary core on the solids that it ultimately accretes. We find that a critical transition occurs where very hot (rapidly accreting)…
Linking atmospheric characteristics of planets to their formation pathways is a central theme in the study of extrasolar planets. Although the 12C/13C isotope ratio shows little variation in the solar system, the atmosphere of a super-Jupiter was recently shown to be rich in 13CO, possibly as a result of dominant ice accretion beyond the CO snowline during its formation. In this paper we aim to measure the 12CO/13CO isotopologue ratio of a young, isolated brown dwarf. While the general atmospheric characteristics of young, low mass brown dwarfs are expected to be very similar to those of super…
We present the confirmation and characterization of three hot Jupiters, TOI-1181b, TOI-1516b, and TOI-2046b, discovered by the TESS space mission. The reported hot Jupiters have orbital periods between 1.4 and 2.05 days. The masses of the three planets are $1.18\pm0.14$ M$_{\mathrm{J}}$, $3.16\pm0.12$\, M$_{\mathrm{J}}$, and 2.30 $\pm 0.28$ M$_{\mathrm{J}}$, for TOI-1181b, TOI-1516b, and TOI-2046b, respectively. The stellar host of TOI-1181b is a F9IV star, whereas TOI-1516b and TOI-2046b orbit F main sequence host stars. The ages of the first two systems are in the range of 2-5 Gyrs. However,…
Detecting and characterising exoworlds around very young stars (age$<$10 Myr) are key aspects of exoplanet demographic studies, especially for understanding the mechanisms and timescales of planet formation and migration. However, detection using the radial velocity method alone can be very challenging, since the amplitude of the signals due to magnetic activity of such stars can be orders of magnitude larger than those induced even by massive planets. We observed the very young ($\sim$2 Myr) and very active star V830 Tau with the HARPS-N spectrograph to independently confirm and characterise …
最近的{ \em Kepler}观测显示，在$0.02-0.2$ AU的内部，有大量的地球大小到海王星大小的“热”行星。我们认为，这些较小的行星是大质量巨行星的残余物，它们向内迁移的速度比它们收缩的速度要快。我们表明，这种破坏自然发生在行星形成的潮汐缩小假说的框架。我们发现，这种“热破裂”发生的特征行星-恒星分离是$R \approx 0.03-0.2$ AU。这个结果与行星的胚胎质量无关，但取决于圆盘中的吸积速率。在高增长率下，$\dot M \simgt 10^{-6}\msun$ yr $^{-1}$，胚胎不能足够快地收缩并被破坏。在后期，当生长速率下降到$\dot M \simlt 10^{-8} \msun$ yr $^{-1}$时，胚胎迁移足够慢而不被破坏。这些“迟到者”也许可以解释众所周知的热木星人口。如果I型迁移机制效率低下，那么我们的模型预测，当迁移率突然从II型转换到I型时，在$R\sim 0.1$ AU处会有行星堆积。
Candidate free-floating super-Jupiters in the young sigma Orionis open cluster
在猎户座σ疏散星团中发现了自由漂浮的亚恒星候选者，其估计的理论质量低至约5个木星质量。随着与行星质量域重叠的增加，这些物体如何形成的问题变得重要。确定它们的数量密度以及是否存在质量截止极限对于了解它们的形成至关重要。我们建议在集群中寻找质量较低的物体，并确定低质量下质量函数的形状。使用新的和（重新分析的）已发表的IZJHKs[3.6]-[8.0]波段数据，面积为840弧分2，我们根据它们的预期星等和颜色，在J=19.5-21.5等范围内搜索LT型星团成员候选者。除了恢复T型天体S Ori 70和其他两个已知天体外，我们还发现了三个新的星团候选成员，S Ori 72-74，J=21等，距离星团中心12弧分以内。它们的理论质量为4（-2，+3）M_Jup，是太阳系外通过直接成像探测到的质量最小的自由漂浮天体之一。档案斯皮策[3.6]-[5.8]波段图像中的测光推断，S Ori 72是L/T过渡候选者，S Ori 73是T型候选者，遵循中红外预期的集群序列。最后，测光质量较低的L型候选星S Ori 74位于猎户座σ的一颗恒星成员的11.8角秒（~4250 AU）处，可能是一颗伴星。在完成J=21.1等的污染校正后，我们估计在6-4 M_Jup的质量区间内仍有0到2个星团成员。我们的结果表明，在低于~6木星质量的亚恒星质量谱中可能有一个周转，这可以通过更广泛和更深入的光度测量来进一步研究。
Isotope abundance ratios play an important role in astronomy and planetary sciences, providing insights in the origin and evolution of the Solar System, interstellar chemistry, and stellar nucleosynthesis. In contrast to deuterium/hydrogen ratios, carbon isotope ratios are found to be roughly constant (~89) in the Solar System, but do vary on galactic scales with 12C/13C~68 in the current local interstellar medium. In molecular clouds and protoplanetary disks, 12CO/13CO isotopologue ratios can be altered by ice and gas partitioning, low-temperature isotopic ion exchange reactions, and isotope-…
K2 reveals pulsed accretion driven by the 2 Myr old hot Jupiter CI Tau b
CI Tau是一颗年轻（约200万年前）的经典金牛座T星，位于金牛座恒星形成区。径向速度观测表明，它拥有一颗彗星大小的行星，轨道周期约为9天。在这项工作中，我们分析了CI Tau的光度变化的时间序列，如K2所见。光变曲线显示恒星自转周期约为6.6 d。虽然没有证据表明CI Tau b会凌日主星，但在光变曲线中也有一个~9 d的信号。我们相信这很可能是行星盘的相互作用干扰了恒星上的吸积流，导致了行星轨道的~9 d周期对亮度的周期性调制。
Context. The birth environments of planetary systems are thought to influence planet formation and orbital evolution, through external photoevaporation and stellar flybys. Recent work has claimed observational support for this, in the form of a correlation between the properties of planetary systems and the local Galactic phase space density of the host star. In particular, Hot Jupiters are found overwhelmingly around stars in regions of high phase space density, which may reflect a formation environment with high stellar density. Aims. We instead investigate whether the high phase space densi…
A Sulfur-Rich Atmosphere for the Young Jupiter Analog AF Lep b Reveals Significant Solid Accretion
University of California, Los Angeles（加州大学洛杉矶分校）；Northwestern University（西北大学）；University of California, Santa Cruz（加州大学圣克鲁兹分校）；University of California, San Diego（加州大学圣迭戈分校）；National Astronomical Observatory of Japan（日本国立天文台）；European Southern Observatory（欧洲南方天文台）；New Mexico State University（新墨西哥州立大学）
We report the discovery of TOI-4562 b (TIC-349576261), a Jovian planet orbiting a young F7V-type star, younger than the Praesepe/Hyades clusters (< $700$ Myr). This planet stands out because of its unusually long orbital period for transiting planets with known masses ($P_{\mathrm{orb}}$ = $225.11781^{+0.00025}_{-0.00022}$ days), and because it has a substantial eccentricity ($e$ = $0.76^{+0.02}_{-0.02}$). The location of TOI-4562 near the southern continuous viewing zone of TESS allowed observations throughout 25 sectors, enabling an unambiguous period measurement from TESS alone. Alongside t…
Unraveling the Mystery of the Peculiar and Young Hot Jupiter CoRoT-2b II: Phase Resolved Emission Spectroscopy with VLT/CRIRES+ and Gemini-S/IGRINS
University of Warwick（华威大学）；Université de Montréal（蒙特利尔大学）；Institut de Recherche en Astrophysique et Planétologie (IRAP)（天体物理学与行星学研究所在）；Instituto de Astrofísica de Andalucía (IAA-CSIC)（安达卢西亚天体物理研究所）；Department of Astronomy, University of Michigan（密歇根大学天文学系）
Unraveling the Mystery of the Peculiar and Young Hot Jupiter CoRoT-2b. I. H$_2$O and CO Detection from Dayside Observations with Gemini-S/IGRINS
Trottier Institute for Research on Exoplanets（系外行星特罗蒂尔研究所）；Université de Montréal（蒙特利尔大学）；University of Waterloo（滑铁卢大学）；Caltech（加州理工学院）；McGill University（麦吉尔大学）；Observatoire astronomique de l’Universit（大学天文台）
In the study of planetary habitability and terrestrial atmospheric evolution, the divergence of surface conditions for Venus and Earth remains an area of active research. Among the intrinsic and external influences on the Venusian climate history are orbital changes due to giant planet migration that have both variable incident flux and tidal heating consequences. Here, we present the results of a study that explores the effect of Jupiter's location on the orbital parameters of Venus and subsequent potential water loss scenarios. Our dynamical simulations show that various scenarios of Jovian …
The James Webb Space Telescope (JWST), currently scheduled to launch in 2021, will dramatically advance our understanding of exoplanetary systems with its ability to directly image and characterise planetary-mass companions at wide separations through coronagraphy. Using state-of-the-art simulations of JWST performance, in combination with the latest evolutionary models, we present the most sophisticated simulated mass sensitivity limits of JWST coronagraphy to date. In particular, we focus our efforts towards observations of members within the nearby young moving groups $β$ Pictoris and TW Hy…
Current theories of planetary evolution predict that infant giant planets have large radii and very low densities before they slowly contract to reach their final size after about several hundred million years. These theoretical expectations remain untested to date, despite the increasing number of exoplanetary discoveries, as the detection and characterisation of very young planets is extremely challenging due to the intense stellar activity of their host stars. However, the recent discoveries of young planetary transiting systems allow to place initial constraints on evolutionary models. Wit…
The JWST Sub-Jupiters Survey: Direct Imaging Discovery of a Giant Planet and a Debris Disk Around the Young M-dwarf RX J0534.0-0221
Northwestern University（西北大学）；University of Arizona（亚利桑那大学）；University of Maryland, Baltimore County（马里兰大学巴尔的摩分校）；NASA-GSFC（美国宇航局戈达德太空飞行中心）；Space Telescope Science Institute (STScI)（空间望远镜科学研究所）
