M. Ghachoui, B. V. Rackham, M. Dévora-Pajares, J. Chouqar, M. Timmermans, L. Kaltenegger, D. Sebastian, F. J. Pozuelos, J. D. Eastman, A. J. Burgasser, F. Murgas, K. G. Stassun, M. Gillon, Z. Benkhaldoun, E. Palle, L. Delrez, J. M. Jenkins, K. Barkaoui, N. Narita, J. P. de Leon, M. Mori, A. Shporer, P. Rowden, V. Kostov, G. Fűrész, K. A. Collins, R. P. Schwarz, D. Charbonneau, N. M. Guerrero, G. Ricker, E. Jehin, A. Fukui, Y. Kawai, Y. Hayashi, E. Esparza-Borges, H. Parviainen, C. A. Clark, D. R. Ciardi, A. S. Polanski, J. Schleider, E. A. Gilbert, I. J. M. Crossfield, T. Barclay, C. D. Dressing, P. R. Karpoor, E. Softich, R. Gerasimov, F. Davoudi
We present the validation of two TESS super-Earth candidates transiting the mid-M dwarfs TOI-6002 and TOI-5713 every 10.90 and 10.44 days, respectively. The first star (TOI-6002) is located $32.038pm0.019$ pc away, with a radius of $0.2409^{+0.0066}_{-0.0065} R_odot$, a mass of $0.2105^{+0.0049}_{-0.0048} M_odot$ and an effective temperature of $3229^{+77}_{-57}$ K. The second star (TOI-5713) is located $40.946pm0.032$ pc away, with a radius of $0.2985^{+0.0073}_{-0.0072} R_odot$, a mass of $0.2653pm0.0061 M_odot$ and an effective temperature of $3225^{+41}_{-40}$ K. We validated the planets using TESS data, ground-based multi-wavelength photometry from many ground-based facilities, as well as high-resolution AO observations from Keck/NIRC2. TOI-6002 b has a radius of $1.65^{+0.22}_{-0.19} R_oplus$ and receives $1.77^{+0.16}_{-0.11} S_oplus$. TOI-5713 b has a radius of $1.77_{-0.11}^{+0.13} R_oplus$ and receives $2.42pm{0.11} S_oplus$. Both planets are located near the radius valley and near the inner edge of the habitable zone of their host stars, which makes them intriguing targets for future studies to understand the formation and evolution of small planets around M-dwarf stars.
{"title":"TESS discovery of two super-Earths orbiting the M-dwarf stars TOI-6002 and TOI-5713 near the radius valley","authors":"M. Ghachoui, B. V. Rackham, M. Dévora-Pajares, J. Chouqar, M. Timmermans, L. Kaltenegger, D. Sebastian, F. J. Pozuelos, J. D. Eastman, A. J. Burgasser, F. Murgas, K. G. Stassun, M. Gillon, Z. Benkhaldoun, E. Palle, L. Delrez, J. M. Jenkins, K. Barkaoui, N. Narita, J. P. de Leon, M. Mori, A. Shporer, P. Rowden, V. Kostov, G. Fűrész, K. A. Collins, R. P. Schwarz, D. Charbonneau, N. M. Guerrero, G. Ricker, E. Jehin, A. Fukui, Y. Kawai, Y. Hayashi, E. Esparza-Borges, H. Parviainen, C. A. Clark, D. R. Ciardi, A. S. Polanski, J. Schleider, E. A. Gilbert, I. J. M. Crossfield, T. Barclay, C. D. Dressing, P. R. Karpoor, E. Softich, R. Gerasimov, F. Davoudi","doi":"arxiv-2408.00709","DOIUrl":"https://doi.org/arxiv-2408.00709","url":null,"abstract":"We present the validation of two TESS super-Earth candidates transiting the\u0000mid-M dwarfs TOI-6002 and TOI-5713 every 10.90 and 10.44 days, respectively.\u0000The first star (TOI-6002) is located $32.038pm0.019$ pc away, with a radius of\u0000$0.2409^{+0.0066}_{-0.0065} R_odot$, a mass of $0.2105^{+0.0049}_{-0.0048}\u0000M_odot$ and an effective temperature of $3229^{+77}_{-57}$ K. The second star\u0000(TOI-5713) is located $40.946pm0.032$ pc away, with a radius of\u0000$0.2985^{+0.0073}_{-0.0072} R_odot$, a mass of $0.2653pm0.0061 M_odot$ and\u0000an effective temperature of $3225^{+41}_{-40}$ K. We validated the planets\u0000using TESS data, ground-based multi-wavelength photometry from many\u0000ground-based facilities, as well as high-resolution AO observations from\u0000Keck/NIRC2. TOI-6002 b has a radius of $1.65^{+0.22}_{-0.19} R_oplus$ and\u0000receives $1.77^{+0.16}_{-0.11} S_oplus$. TOI-5713 b has a radius of\u0000$1.77_{-0.11}^{+0.13} R_oplus$ and receives $2.42pm{0.11} S_oplus$. Both\u0000planets are located near the radius valley and near the inner edge of the\u0000habitable zone of their host stars, which makes them intriguing targets for\u0000future studies to understand the formation and evolution of small planets\u0000around M-dwarf stars.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"79 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141880936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrew D. Sellek, Tommaso Grassi, Giovanni Picogna, Christian Rab, Cathie J. Clarke, Barbara Ercolano
Context: Photoevaporation is an important process for protoplanetary disc dispersal but there has so far been a lack of consensus from simulations over the mass-loss rates and the most important part of the high-energy spectrum for driving the wind. Aims: We aim to isolate the origins of these discrepancies through carefully-benchmarked hydrodynamic simulations of X-ray photoevaporation with time-dependent thermochemistry calculated on the fly. Methods: We conduct hydrodynamic simulations with pluto where the thermochemistry is calculated using prizmo. We explore the contribution of certain key microphysical processes and the impact of using different spectra used previously in literature studies. Results: We find that additional cooling results from the excitation of O by neutral H, which leads to dramatically reduced mass-loss across the disc compared to previous X-ray photoevaporation models, with an integrated rate of 10^-9 Msun/yr. Such rates would allow for longer-lived discs than previously expected from population synthesis. An alternative spectrum with less soft X-ray produces mass-loss rates around a factor of 2-3 times lower. The chemistry is significantly out of equilibrium, with the survival of H2 into the wind aided by advection. This leads to its role as the dominant coolant at 10s au - thus stabilising a larger radial temperature gradient across the wind - as well as providing a possible wind tracer.
背景：光蒸发是原行星盘分散的一个重要过程，但迄今为止，模拟结果在质量损失率和驱动风的高能谱最重要部分上缺乏共识。目的：我们的目标是通过仔细基准化的 X 射线光蒸发流体力学模拟，以及实时计算的随时间变化的热化学过程，来分离出这些差异的根源：我们对冥王星进行了流体力学模拟，其中的热化学是用 prizmo 计算的。我们探索了某些关键微物理过程的贡献，以及使用文献研究中使用的不同光谱的影响。结果：我们发现额外的冷却来自于中性 H 对 O 的激发，与之前的 X 射线光蒸发模型相比，这导致整个圆盘的质量损失显著降低，综合速率为 10^-9 Msun/年。这样的速率将使圆盘的寿命比之前的种群合成所预期的更长。使用较少软 X 射线的替代光谱产生的质量损失率大约低 2-3 倍。化学反应明显失去平衡，H2 在平流的帮助下进入风中。这导致它成为 10s au 处的主要冷却剂--从而稳定了整个风的较大径向温度梯度--并提供了一种可能的风向跟踪器。
{"title":"Photoevaporation of protoplanetary discs with PLUTO+PRIZMO I. Lower X-ray-driven mass-loss rates due to enhanced cooling","authors":"Andrew D. Sellek, Tommaso Grassi, Giovanni Picogna, Christian Rab, Cathie J. Clarke, Barbara Ercolano","doi":"arxiv-2408.00848","DOIUrl":"https://doi.org/arxiv-2408.00848","url":null,"abstract":"Context: Photoevaporation is an important process for protoplanetary disc\u0000dispersal but there has so far been a lack of consensus from simulations over\u0000the mass-loss rates and the most important part of the high-energy spectrum for\u0000driving the wind. Aims: We aim to isolate the origins of these discrepancies\u0000through carefully-benchmarked hydrodynamic simulations of X-ray\u0000photoevaporation with time-dependent thermochemistry calculated on the fly.\u0000Methods: We conduct hydrodynamic simulations with pluto where the\u0000thermochemistry is calculated using prizmo. We explore the contribution of\u0000certain key microphysical processes and the impact of using different spectra\u0000used previously in literature studies. Results: We find that additional cooling\u0000results from the excitation of O by neutral H, which leads to dramatically\u0000reduced mass-loss across the disc compared to previous X-ray photoevaporation\u0000models, with an integrated rate of 10^-9 Msun/yr. Such rates would allow for\u0000longer-lived discs than previously expected from population synthesis. An\u0000alternative spectrum with less soft X-ray produces mass-loss rates around a\u0000factor of 2-3 times lower. The chemistry is significantly out of equilibrium,\u0000with the survival of H2 into the wind aided by advection. This leads to its\u0000role as the dominant coolant at 10s au - thus stabilising a larger radial\u0000temperature gradient across the wind - as well as providing a possible wind\u0000tracer.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"128 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141931837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Perianne E. Johnson, Leslie A. Young, David Nesvorny, Xi Zhang
We estimate the loss of nitrogen from Pluto over its lifetime, including the giant planet instability period, which we term the "Wild Years." We analyze the orbital migration of 53 simulated Plutinos, which are Kuiper Belt Objects (KBOs) captured into 3:2 mean-motion resonance with Neptune during the instability. This orbital migration brought the Plutinos from 20 to 30 au to their present-day orbits near 40 au along a nonlinear path that includes orbits with semimajor axes from 10 to 100 au. We model the thermal history that results from this migration and estimate the volatile loss rates due to the ever-changing thermal environment. Due to the early Sun's enhanced ultraviolet radiation, the photochemical destruction rate during the Wild Years was a factor of 100 higher than the present-day rate, but this only results in a loss of ~10 m global equivalent layer (GEL). The enhanced Jeans escape rate varies wildly with time, and a net loss of ~100 cm GEL is predicted. Additionally, we model the impact history during the migration and find that impacts are a net source, not loss, of N2, contributing ~100 cm GEL. The 100 cm GEL is 0.1% of the amount of N2 in Sputnik Planitia. We therefore conclude that Pluto did not lose an excessive amount of volatiles during the Wild Years, and its primordial volatile inventory can be approximated as its present-day inventory. However, significant fractions of this small total loss of N2 occurred during the Wild Years, so estimates made using present-day rates will be underestimates.
我们估算了冥王星在其生命周期内的氮损失，包括巨行星不稳定期，我们称之为 "狂野岁月"。我们分析了53颗模拟冥王星的轨道迁移，这些冥王星是柯伊伯带天体（KBOs），在不稳定时期被捕获并与海王星产生3:2的平均运动共振。这种轨道迁移将冥王星从 20 到 30 au 的轨道带到了它们今天接近 40 au 的轨道，沿着一条非线性路径，包括半主轴从 10 到 100 au 的轨道。我们模拟了这一迁移所产生的热历史，并估算了由于不断变化的热环境所导致的挥发损失率。由于早期太阳的紫外线辐照增强，狂野年代的光化学破坏率比现在高出 100 倍，但这只造成了约 10 米的全球等效层（GEL）损失。增强的杰恩斯逃逸率随时间变化很大，预计净损失约 100 厘米的全球等效层（GEL）。此外，我们模拟了迁移过程中的撞击历史，发现撞击是 N2 的净来源，而不是损失，贡献了 ~100 厘米的 GEL。这100厘米的GEL相当于Sputnik Planitia中N2数量的0.1%。因此我们得出结论，冥王星在狂野岁月期间并没有损失过多的挥发物，其原始挥发物存量可以近似为现在的存量。然而，在这一小部分N2的总损失中，有相当一部分是在荒年期间发生的，因此用现在的速率进行估算将是低估的。
{"title":"Nitrogen Loss from Pluto's Birth to the Present Day via Atmospheric Escape, Photochemical Destruction, and Impact Erosion","authors":"Perianne E. Johnson, Leslie A. Young, David Nesvorny, Xi Zhang","doi":"arxiv-2408.00625","DOIUrl":"https://doi.org/arxiv-2408.00625","url":null,"abstract":"We estimate the loss of nitrogen from Pluto over its lifetime, including the\u0000giant planet instability period, which we term the \"Wild Years.\" We analyze the\u0000orbital migration of 53 simulated Plutinos, which are Kuiper Belt Objects\u0000(KBOs) captured into 3:2 mean-motion resonance with Neptune during the\u0000instability. This orbital migration brought the Plutinos from 20 to 30 au to\u0000their present-day orbits near 40 au along a nonlinear path that includes orbits\u0000with semimajor axes from 10 to 100 au. We model the thermal history that\u0000results from this migration and estimate the volatile loss rates due to the\u0000ever-changing thermal environment. Due to the early Sun's enhanced ultraviolet\u0000radiation, the photochemical destruction rate during the Wild Years was a\u0000factor of 100 higher than the present-day rate, but this only results in a loss\u0000of ~10 m global equivalent layer (GEL). The enhanced Jeans escape rate varies\u0000wildly with time, and a net loss of ~100 cm GEL is predicted. Additionally, we\u0000model the impact history during the migration and find that impacts are a net\u0000source, not loss, of N2, contributing ~100 cm GEL. The 100 cm GEL is 0.1% of\u0000the amount of N2 in Sputnik Planitia. We therefore conclude that Pluto did not\u0000lose an excessive amount of volatiles during the Wild Years, and its primordial\u0000volatile inventory can be approximated as its present-day inventory. However,\u0000significant fractions of this small total loss of N2 occurred during the Wild\u0000Years, so estimates made using present-day rates will be underestimates.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"215 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141880937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yoshihide Yamato, Yuri Aikawa, Viviana V. Guzmán, Kenji Furuya, Shota Notsu, Gianni Cataldi, Karin I. Öberg, Chunhua Qi, Charles J. Law, Jane Huang, Richard Teague, Romane Le Gal
Characterizing the chemistry of complex organic molecules (COMs) at the epoch of planet formation provides insights into the chemical evolution of the interstellar medium (ISM) and the origin of organic materials in our Solar System. We report a detection of dimethyl ether (CH$_3$OCH$_3$) in the disk around the Herbig Ae star MWC 480 with the sensitive Atacama Large Millimeter/submillimeter Array observations. This is the first detection of CH$_3$OCH$_3$ in a non-transitional Class II disk. The spatially unresolved, compact (${lesssim}$25 au in radius) nature, the broad line width ($sim$30 km s$^{-1}$), and the high excitation temperature (${sim}$200 K) indicate sublimation of COMs in the warm inner disk. Despite the detection of CH$_3$OCH$_3$, methanol (CH$_3$OH), the most abundant COM in the ISM, has not been detected, from which we constrain the column density ratio of CH$_3$OCH$_3$/CH$_3$OH ${gtrsim}$7. This high ratio may indicate the reprocessing of COMs during the disk phase, as well as the effect of the physical structure in the inner disk. We also find that this ratio is higher than in COM-rich transition disks recently discovered. This may indicate that, in the full disk of MWC 480, COMs have experienced substantial chemical reprocessing in the innermost region, while the COM emission in the transition disks predominantly traces the inherited ice sublimating at the dust cavity edge located at larger radii (${gtrsim}$20 au).
{"title":"Detection of Dimethyl Ether in the Central Region of the MWC 480 Protoplanetary Disk","authors":"Yoshihide Yamato, Yuri Aikawa, Viviana V. Guzmán, Kenji Furuya, Shota Notsu, Gianni Cataldi, Karin I. Öberg, Chunhua Qi, Charles J. Law, Jane Huang, Richard Teague, Romane Le Gal","doi":"arxiv-2407.21518","DOIUrl":"https://doi.org/arxiv-2407.21518","url":null,"abstract":"Characterizing the chemistry of complex organic molecules (COMs) at the epoch\u0000of planet formation provides insights into the chemical evolution of the\u0000interstellar medium (ISM) and the origin of organic materials in our Solar\u0000System. We report a detection of dimethyl ether (CH$_3$OCH$_3$) in the disk\u0000around the Herbig Ae star MWC 480 with the sensitive Atacama Large\u0000Millimeter/submillimeter Array observations. This is the first detection of\u0000CH$_3$OCH$_3$ in a non-transitional Class II disk. The spatially unresolved,\u0000compact (${lesssim}$25 au in radius) nature, the broad line width ($sim$30 km\u0000s$^{-1}$), and the high excitation temperature (${sim}$200 K) indicate\u0000sublimation of COMs in the warm inner disk. Despite the detection of\u0000CH$_3$OCH$_3$, methanol (CH$_3$OH), the most abundant COM in the ISM, has not\u0000been detected, from which we constrain the column density ratio of\u0000CH$_3$OCH$_3$/CH$_3$OH ${gtrsim}$7. This high ratio may indicate the\u0000reprocessing of COMs during the disk phase, as well as the effect of the\u0000physical structure in the inner disk. We also find that this ratio is higher\u0000than in COM-rich transition disks recently discovered. This may indicate that,\u0000in the full disk of MWC 480, COMs have experienced substantial chemical\u0000reprocessing in the innermost region, while the COM emission in the transition\u0000disks predominantly traces the inherited ice sublimating at the dust cavity\u0000edge located at larger radii (${gtrsim}$20 au).","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Constraining the formation processes of small solar system bodies is crucial for gaining insights into planetesimal formation. Their bulk densities, determined by their compressive strengths, offer valuable information about their formation history. In this paper, we utilize a formulation of the compressive strength of dust aggregates obtained from dust $N$-body simulations to establish the relation between bulk density and diameter. We find that this relation can be effectively approximated by a polytrope with an index of 0.5, coupled with a formulation of the compressive strength of dust aggregates. The lowest-density trans-Neptunian objects (TNOs) and main-belt asteroids (MBAs) are well reproduced by dust aggregates composed of 0.1-$mathrm{mu}$m-sized grains. However, most TNOs, MBAs, comets, and near-Earth asteroids (NEAs) exhibit higher densities, suggesting the influence of compaction mechanisms such as collision, dust grain disruption, sintering, or melting, leading to further growth. We speculate that there are two potential formation paths for small solar system bodies: one involves the direct coagulation of primordial dust grains, resulting in the formation of first-generation planetesimals, including the lowest-density TNOs, MBAs, and parent bodies of comets and NEAs. In this case, comets and NEAs are fragments or rubble piles of first-generation planetesimals, and objects themselves or rubbles are composed of 0.1-$mathrm{mu}$m-sized grains. The other path involves further potential fragmentation of first-generation planetesimals into compact dust aggregates observed in protoplanetary disks, resulting in the formation of second-generation planetesimals composed of compact dust aggregates, which may contribute to explaining another formation process of comets and NEAs.
{"title":"The Bulk Densities of Small Solar System Bodies as a Probe of Planetesimal Formation","authors":"Misako Tatsuuma, Akimasa Kataoka, Hidekazu Tanaka, Tristan Guillot","doi":"arxiv-2407.21386","DOIUrl":"https://doi.org/arxiv-2407.21386","url":null,"abstract":"Constraining the formation processes of small solar system bodies is crucial\u0000for gaining insights into planetesimal formation. Their bulk densities,\u0000determined by their compressive strengths, offer valuable information about\u0000their formation history. In this paper, we utilize a formulation of the\u0000compressive strength of dust aggregates obtained from dust $N$-body simulations\u0000to establish the relation between bulk density and diameter. We find that this\u0000relation can be effectively approximated by a polytrope with an index of 0.5,\u0000coupled with a formulation of the compressive strength of dust aggregates. The\u0000lowest-density trans-Neptunian objects (TNOs) and main-belt asteroids (MBAs)\u0000are well reproduced by dust aggregates composed of 0.1-$mathrm{mu}$m-sized\u0000grains. However, most TNOs, MBAs, comets, and near-Earth asteroids (NEAs)\u0000exhibit higher densities, suggesting the influence of compaction mechanisms\u0000such as collision, dust grain disruption, sintering, or melting, leading to\u0000further growth. We speculate that there are two potential formation paths for\u0000small solar system bodies: one involves the direct coagulation of primordial\u0000dust grains, resulting in the formation of first-generation planetesimals,\u0000including the lowest-density TNOs, MBAs, and parent bodies of comets and NEAs.\u0000In this case, comets and NEAs are fragments or rubble piles of first-generation\u0000planetesimals, and objects themselves or rubbles are composed of\u00000.1-$mathrm{mu}$m-sized grains. The other path involves further potential\u0000fragmentation of first-generation planetesimals into compact dust aggregates\u0000observed in protoplanetary disks, resulting in the formation of\u0000second-generation planetesimals composed of compact dust aggregates, which may\u0000contribute to explaining another formation process of comets and NEAs.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jingwen Zhang, Daniel Huber, Lauren M. Weiss, Jerry W. Xuan, Jennifer A. Burt, Fei Dai, Nicholas Saunders, Erik A. Petigura, Ryan A. Rubenzahl, Joshua N. Winn, Sharon X. Wang, Judah Van Zandt, Max Brodheim, Zachary R. Claytor, Ian Crossfield, William Deich, Benjamin J. Fulton, Steven R. Gibson, Grant M. Hill, Bradford Holden, Aaron Householder, Andrew W. Howard, Howard Isaacson, Stephen Kaye, Kyle Lanclos, Russ R. Laher, Jack Lubin, Joel Payne, Arpita Roy, Christian Schwab, Abby P. Shaum, Josh Walawender, Edward Wishnow, Sherry Yeh
Characterizing outer companions to hot Jupiters plays a crucial role in deciphering their origins. We present the discovery of a long-period giant planet, HD 118203 c ($m_{c}=11.9^{+0.69}_{-0.63} mathrm{M_{J}}$, $a_{c}=5.36^{+0.09}_{-0.10}$ AU, $e_{c}=0.26^{+0.03}_{-0.02}$) exterior to previously known close-in eccentric hot Jupiter HD 118203 b ($P_{b}=6.135 mathrm{days}$, $m_{b}=2.14pm{0.12} mathrm{M_{J}}$, $r_{b}=1.14pm{0.029} mathrm{R_{J}}$, $e_{b}=0.31pm{0.007}$) based on twenty-year radial velocity observations. Using Rossiter-McLaughlin (RM) observations from the Keck Planet Finder (KPF), we measured a low sky-projected obliquity $lambda_{b}=-11^{circ}.7^{+7.6}_{-10}$ for HD 118203 b and detected stellar oscillations in the host star, confirming its evolved status. Combining the RM observation with the stellar inclination measurement, we constrained the true obliquity of HD 118203 b as $Psi_{b}<33^{circ}.5 (2sigma)$, indicating the orbit normal of the hot Jupiter nearly aligned with the stellar spin axis. Furthermore, by combining radial velocities and Hipparcos-Gaia astrometric acceleration, we constrained the line-of-sight mutual inclination between the hot Jupiter and the outer planet to be $9^{circ}.8^{+16.2}_{-9.3}$ at $2sigma$ level. HD 118203 is the first hot Jupiter system where both the true obliquity of the hot Jupiter and the mutual inclination between inner and outer planets have been determined. Our results are consistent with a system-wide alignment, with low mutual inclinations between the outer giant planet, the inner hot Jupiter, and the host star. This alignment, along with the moderate eccentricity of HD 118203 c, implies that the system may have undergone coplanar high-eccentricity tidal migration. Under this framework, our dynamical analysis suggests an initial semi-major axis of 0.3 to 3.2 AU for the proto-hot Jupiter.
{"title":"A Testbed for Tidal Migration: the 3D Architecture of an Eccentric Hot Jupiter HD 118203 b Accompanied by a Possibly Aligned Outer Giant Planet","authors":"Jingwen Zhang, Daniel Huber, Lauren M. Weiss, Jerry W. Xuan, Jennifer A. Burt, Fei Dai, Nicholas Saunders, Erik A. Petigura, Ryan A. Rubenzahl, Joshua N. Winn, Sharon X. Wang, Judah Van Zandt, Max Brodheim, Zachary R. Claytor, Ian Crossfield, William Deich, Benjamin J. Fulton, Steven R. Gibson, Grant M. Hill, Bradford Holden, Aaron Householder, Andrew W. Howard, Howard Isaacson, Stephen Kaye, Kyle Lanclos, Russ R. Laher, Jack Lubin, Joel Payne, Arpita Roy, Christian Schwab, Abby P. Shaum, Josh Walawender, Edward Wishnow, Sherry Yeh","doi":"arxiv-2407.21377","DOIUrl":"https://doi.org/arxiv-2407.21377","url":null,"abstract":"Characterizing outer companions to hot Jupiters plays a crucial role in\u0000deciphering their origins. We present the discovery of a long-period giant\u0000planet, HD 118203 c ($m_{c}=11.9^{+0.69}_{-0.63} mathrm{M_{J}}$,\u0000$a_{c}=5.36^{+0.09}_{-0.10}$ AU, $e_{c}=0.26^{+0.03}_{-0.02}$) exterior to\u0000previously known close-in eccentric hot Jupiter HD 118203 b ($P_{b}=6.135\u0000mathrm{days}$, $m_{b}=2.14pm{0.12} mathrm{M_{J}}$, $r_{b}=1.14pm{0.029}\u0000mathrm{R_{J}}$, $e_{b}=0.31pm{0.007}$) based on twenty-year radial velocity\u0000observations. Using Rossiter-McLaughlin (RM) observations from the Keck Planet\u0000Finder (KPF), we measured a low sky-projected obliquity\u0000$lambda_{b}=-11^{circ}.7^{+7.6}_{-10}$ for HD 118203 b and detected stellar\u0000oscillations in the host star, confirming its evolved status. Combining the RM\u0000observation with the stellar inclination measurement, we constrained the true\u0000obliquity of HD 118203 b as $Psi_{b}<33^{circ}.5 (2sigma)$, indicating the\u0000orbit normal of the hot Jupiter nearly aligned with the stellar spin axis.\u0000Furthermore, by combining radial velocities and Hipparcos-Gaia astrometric\u0000acceleration, we constrained the line-of-sight mutual inclination between the\u0000hot Jupiter and the outer planet to be $9^{circ}.8^{+16.2}_{-9.3}$ at\u0000$2sigma$ level. HD 118203 is the first hot Jupiter system where both the true\u0000obliquity of the hot Jupiter and the mutual inclination between inner and outer\u0000planets have been determined. Our results are consistent with a system-wide\u0000alignment, with low mutual inclinations between the outer giant planet, the\u0000inner hot Jupiter, and the host star. This alignment, along with the moderate\u0000eccentricity of HD 118203 c, implies that the system may have undergone\u0000coplanar high-eccentricity tidal migration. Under this framework, our dynamical\u0000analysis suggests an initial semi-major axis of 0.3 to 3.2 AU for the proto-hot\u0000Jupiter.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Akshay Robert, Jay Farihi, Vincent Van Eylen, Amornrat Aungwerojwit, Boris T. Gänsicke, Seth Redfield, Vikram S. Dhillon, Thomas R. Marsh, Andrew Swan
This paper investigates the frequency of transiting planetary systems around metal-polluted white dwarfs using high-cadence photometry from ULTRACAM and ULTRASPEC on the ground, and space-based observations with TESS. Within a sample of 313 metal-polluted white dwarfs with available TESS light curves, two systems known to have irregular transits are blindly recovered by box-least-squares and Lomb-Scargle analyses, with no new detections, yielding a transit fraction of 0.8 (-0.4, +0.6) per cent. Planet detection sensitivities are determined using simulated transit injection and recovery for all light curves, producing upper limit occurrences over radii from dwarf to Kronian planets, with periods from 1 h to 27 d. The dearth of short-period, transiting planets orbiting polluted white dwarfs is consistent with engulfment during the giant phases of stellar evolution, and modestly constrains dynamical re-injection of planets to the shortest orbital periods. Based on simple predictions of transit probability, where (R + Rp)/a ~ 0.01, the findings here are nominally consistent with a model where 100 per cent of polluted white dwarfs have circumstellar debris near the Roche limit; however, the small sample size precludes statistical confidence in this result. Single transits are also ruled out in all light curves using a search for correlated outliers, providing weak constraints on the role of Oort-like comet clouds in white dwarf pollution.
{"title":"The frequency of transiting planetary systems around polluted white dwarfs","authors":"Akshay Robert, Jay Farihi, Vincent Van Eylen, Amornrat Aungwerojwit, Boris T. Gänsicke, Seth Redfield, Vikram S. Dhillon, Thomas R. Marsh, Andrew Swan","doi":"arxiv-2407.21743","DOIUrl":"https://doi.org/arxiv-2407.21743","url":null,"abstract":"This paper investigates the frequency of transiting planetary systems around\u0000metal-polluted white dwarfs using high-cadence photometry from ULTRACAM and\u0000ULTRASPEC on the ground, and space-based observations with TESS. Within a\u0000sample of 313 metal-polluted white dwarfs with available TESS light curves, two\u0000systems known to have irregular transits are blindly recovered by\u0000box-least-squares and Lomb-Scargle analyses, with no new detections, yielding a\u0000transit fraction of 0.8 (-0.4, +0.6) per cent. Planet detection sensitivities\u0000are determined using simulated transit injection and recovery for all light\u0000curves, producing upper limit occurrences over radii from dwarf to Kronian\u0000planets, with periods from 1 h to 27 d. The dearth of short-period, transiting\u0000planets orbiting polluted white dwarfs is consistent with engulfment during the\u0000giant phases of stellar evolution, and modestly constrains dynamical\u0000re-injection of planets to the shortest orbital periods. Based on simple\u0000predictions of transit probability, where (R + Rp)/a ~ 0.01, the findings here\u0000are nominally consistent with a model where 100 per cent of polluted white\u0000dwarfs have circumstellar debris near the Roche limit; however, the small\u0000sample size precludes statistical confidence in this result. Single transits\u0000are also ruled out in all light curves using a search for correlated outliers,\u0000providing weak constraints on the role of Oort-like comet clouds in white dwarf\u0000pollution.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"66 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Spin-orbit coupling is widespread in binary asteroid systems and it has been widely studied for the case of ellipsoidal secondary. Due to angular momentum exchange, dynamical coupling is stronger when the orbital and rotational angular momenta are closer in magnitudes. Thus, the spin-orbit coupling effects are significantly different for ellipsoidal secondaries and primaries. In the present work, a high-order Hamiltonian model in terms of eccentricity is formulated to study the effects of spin-orbit coupling for the case of ellipsoidal primary body in a binary asteroid system. Our results show that the spin-orbit coupling problem for the ellipsoidal primary holds two kinds of spin equilibrium, while there is only one for the ellipsoidal secondary. In particular, 1:1 and 2:3 spin-orbit resonances are further studied by taking both the classical pendulum approximation as well as adiabatic approximation (Wisdom's perturbative treatment). It shows that there is a critical value of total angular momentum, around which the pendulum approximation fails to work. Dynamical structures are totally different when the total angular momentum is on two sides of the critical value.
{"title":"Spin-orbit coupling of the primary body in a binary asteroid system","authors":"Hanlun Lei","doi":"arxiv-2407.21274","DOIUrl":"https://doi.org/arxiv-2407.21274","url":null,"abstract":"Spin-orbit coupling is widespread in binary asteroid systems and it has been\u0000widely studied for the case of ellipsoidal secondary. Due to angular momentum\u0000exchange, dynamical coupling is stronger when the orbital and rotational\u0000angular momenta are closer in magnitudes. Thus, the spin-orbit coupling effects\u0000are significantly different for ellipsoidal secondaries and primaries. In the\u0000present work, a high-order Hamiltonian model in terms of eccentricity is\u0000formulated to study the effects of spin-orbit coupling for the case of\u0000ellipsoidal primary body in a binary asteroid system. Our results show that the\u0000spin-orbit coupling problem for the ellipsoidal primary holds two kinds of spin\u0000equilibrium, while there is only one for the ellipsoidal secondary. In\u0000particular, 1:1 and 2:3 spin-orbit resonances are further studied by taking\u0000both the classical pendulum approximation as well as adiabatic approximation\u0000(Wisdom's perturbative treatment). It shows that there is a critical value of\u0000total angular momentum, around which the pendulum approximation fails to work.\u0000Dynamical structures are totally different when the total angular momentum is\u0000on two sides of the critical value.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"200 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nicholas Saunders, Samuel K. Grunblatt, Ashley Chontos, Fei Dai, Daniel Huber, Jingwen Zhang, Gudmundur Stefansson, Jennifer L. van Saders, Joshua N. Winn, Daniel Hey, Andrew W. Howard, Benjamin Fulton, Howard Isaacson, Corey Beard, Steven Giacalone, Judah van Zandt, Joseph M. Akana Murphey, Malena Rice, Sarah Blunt, Emma Turtelboom, Paul A. Dalba, Jack Lubin, Casey Brinkman, Emma M. Louden, Emma Page, Cristilyn N. Watkins, Karen A. Collins, Chris Stockdale, Thiam-Guan Tan, Richard P. Schwarz, Bob Massey, Steve B. Howell, Andrew Vanderburg, George R. Ricker, Jon M. Jenkins, Sara Seager, Jessie L. Christiansen, Tansu Daylan, Ben Falk, Max Brodheim, Steven R. Gibson, Grant M. Hill, Bradford Holden, Aaron Householder, Stephen Kaye, Russ R. Laher, Kyle Lanclos, Erik A. Petigura, Arpita Roy, Ryan A. Rubenzahl, Christian Schwab, Abby P. Shaum, Martin M. Sirk, Christopher L. Smith, Josh Walawender, Sherry Yeh
The degree of alignment between a star's spin axis and the orbital plane of its planets (the stellar obliquity) is related to interesting and poorly understood processes that occur during planet formation and evolution. Hot Jupiters orbiting hot stars ($gtrsim$6250 K) display a wide range of obliquities, while similar planets orbiting cool stars are preferentially aligned. Tidal dissipation is expected to be more rapid in stars with thick convective envelopes, potentially explaining this trend. Evolved stars provide an opportunity to test the damping hypothesis, particularly stars that were hot on the main sequence and have since cooled and developed deep convective envelopes. We present the first systematic study of the obliquities of hot Jupiters orbiting subgiants that recently developed convective envelopes using Rossiter-McLaughlin observations. Our sample includes two newly discovered systems in the Giants Transiting Giants Survey (TOI-6029 b, TOI-4379 b). We find that the orbits of hot Jupiters orbiting subgiants that have cooled below $sim$6250 K are aligned or nearly aligned with the spin-axis of their host stars, indicating rapid tidal realignment after the emergence of a stellar convective envelope. We place an upper limit for the timescale of realignment for hot Jupiters orbiting subgiants at $sim$500 Myr. Comparison with a simplified tidal evolution model shows that obliquity damping needs to be $sim$4 orders of magnitude more efficient than orbital period decay to damp the obliquity without destroying the planet, which is consistent with recent predictions for tidal dissipation from inertial waves excited by hot Jupiters on misaligned orbits.
{"title":"TESS Giants Transiting Giants. VI. Newly Discovered Hot Jupiters Provide Evidence for Efficient Obliquity Damping after the Main Sequence","authors":"Nicholas Saunders, Samuel K. Grunblatt, Ashley Chontos, Fei Dai, Daniel Huber, Jingwen Zhang, Gudmundur Stefansson, Jennifer L. van Saders, Joshua N. Winn, Daniel Hey, Andrew W. Howard, Benjamin Fulton, Howard Isaacson, Corey Beard, Steven Giacalone, Judah van Zandt, Joseph M. Akana Murphey, Malena Rice, Sarah Blunt, Emma Turtelboom, Paul A. Dalba, Jack Lubin, Casey Brinkman, Emma M. Louden, Emma Page, Cristilyn N. Watkins, Karen A. Collins, Chris Stockdale, Thiam-Guan Tan, Richard P. Schwarz, Bob Massey, Steve B. Howell, Andrew Vanderburg, George R. Ricker, Jon M. Jenkins, Sara Seager, Jessie L. Christiansen, Tansu Daylan, Ben Falk, Max Brodheim, Steven R. Gibson, Grant M. Hill, Bradford Holden, Aaron Householder, Stephen Kaye, Russ R. Laher, Kyle Lanclos, Erik A. Petigura, Arpita Roy, Ryan A. Rubenzahl, Christian Schwab, Abby P. Shaum, Martin M. Sirk, Christopher L. Smith, Josh Walawender, Sherry Yeh","doi":"arxiv-2407.21650","DOIUrl":"https://doi.org/arxiv-2407.21650","url":null,"abstract":"The degree of alignment between a star's spin axis and the orbital plane of\u0000its planets (the stellar obliquity) is related to interesting and poorly\u0000understood processes that occur during planet formation and evolution. Hot\u0000Jupiters orbiting hot stars ($gtrsim$6250 K) display a wide range of\u0000obliquities, while similar planets orbiting cool stars are preferentially\u0000aligned. Tidal dissipation is expected to be more rapid in stars with thick\u0000convective envelopes, potentially explaining this trend. Evolved stars provide\u0000an opportunity to test the damping hypothesis, particularly stars that were hot\u0000on the main sequence and have since cooled and developed deep convective\u0000envelopes. We present the first systematic study of the obliquities of hot\u0000Jupiters orbiting subgiants that recently developed convective envelopes using\u0000Rossiter-McLaughlin observations. Our sample includes two newly discovered\u0000systems in the Giants Transiting Giants Survey (TOI-6029 b, TOI-4379 b). We\u0000find that the orbits of hot Jupiters orbiting subgiants that have cooled below\u0000$sim$6250 K are aligned or nearly aligned with the spin-axis of their host\u0000stars, indicating rapid tidal realignment after the emergence of a stellar\u0000convective envelope. We place an upper limit for the timescale of realignment\u0000for hot Jupiters orbiting subgiants at $sim$500 Myr. Comparison with a\u0000simplified tidal evolution model shows that obliquity damping needs to be\u0000$sim$4 orders of magnitude more efficient than orbital period decay to damp\u0000the obliquity without destroying the planet, which is consistent with recent\u0000predictions for tidal dissipation from inertial waves excited by hot Jupiters\u0000on misaligned orbits.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"130 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Among the lines of evidence for a buried ocean on Titan is the possible detection, in 2005, by the Permittivity, Wave and Altimetry (PWA) analyzer on board the ESA Huygens probe of Schumann-like Resonances (SR). SR are Extremely Low Frequency electromagnetic waves resonating between two electrically conductive layers. On Titan, it has been proposed that they propagate between the moon's ionosphere and a salty subsurface water ocean. Their characterization by electric field sensors can provide constraints on Titan's cavity characteristics and in particular on the depth of Titan's ocean which is key to better assess Titan's habitability. For this work we have developed a numerical model of Titan's electromagnetic cavity as well as a surrogate model to conduct simulations and sensitivity analyses at a low computational cost. This surrogate model is used both to re-assess PWA/Huygens measurements and to predict the future performance of the EFIELD experiment on board the NASA Dragonfly mission. We demonstrate that the PWA/Huygens measurements, in particular due to their low spectral resolution, do not bring any meaningful constraint on Titan's ocean depth. On the other hand, the finer resolution of the EFIELD experiment and its ability to capture several harmonics of SR should provide more robust constraints on Titan's internal structure, especially if the electrical properties of the ice crust and the atmosphere can be better constrained.
2005年，欧空局惠更斯探测器上的珀耳帖率、波和高度测量（PWA）分析仪可能探测到了类似舒曼共振（SR）的现象，这也是土卫六上埋藏有海洋的证据之一。SR是在两个导电层之间产生共振的极低频电磁波。在土卫六上，有人认为它们是在月球电离层和咸水洋之间传播的。电场传感器对它们的描述可以为土卫六的空隙特征，特别是土卫六海洋的深度提供约束条件，这对于更好地评估土卫六的宜居性至关重要。在这项工作中，我们开发了一个土卫六电磁空腔数值模型和一个代用模型，以便以较低的计算成本进行模拟和敏感性分析。这个代用模型既可用于重新评估PWA/惠更斯测量结果，也可用于预测NASADragonfly任务中的EFIELD实验的未来性能。我们证明，PWA/惠更斯测量数据，特别是由于其光谱分辨率较低，并不能对土卫六的海洋深度带来任何有意义的限制。另一方面，EFIELD 实验更精细的分辨率及其捕捉 SR 的若干谐波的能力应该能够对土卫六的内部结构提供更有力的约束，特别是如果冰壳和大气层的电特性能够得到更好的约束的话。
{"title":"Schumann Resonances as a tool to constrain the depth of Titan's buried water ocean: Re-assessment of Huygens observations and preparation of the EFIELD/Dragonfly experiment","authors":"Paul Lagouanelle, Alice Le Gall","doi":"arxiv-2407.21529","DOIUrl":"https://doi.org/arxiv-2407.21529","url":null,"abstract":"Among the lines of evidence for a buried ocean on Titan is the possible\u0000detection, in 2005, by the Permittivity, Wave and Altimetry (PWA) analyzer on\u0000board the ESA Huygens probe of Schumann-like Resonances (SR). SR are Extremely\u0000Low Frequency electromagnetic waves resonating between two electrically\u0000conductive layers. On Titan, it has been proposed that they propagate between\u0000the moon's ionosphere and a salty subsurface water ocean. Their\u0000characterization by electric field sensors can provide constraints on Titan's\u0000cavity characteristics and in particular on the depth of Titan's ocean which is\u0000key to better assess Titan's habitability. For this work we have developed a\u0000numerical model of Titan's electromagnetic cavity as well as a surrogate model\u0000to conduct simulations and sensitivity analyses at a low computational cost.\u0000This surrogate model is used both to re-assess PWA/Huygens measurements and to\u0000predict the future performance of the EFIELD experiment on board the NASA\u0000Dragonfly mission. We demonstrate that the PWA/Huygens measurements, in\u0000particular due to their low spectral resolution, do not bring any meaningful\u0000constraint on Titan's ocean depth. On the other hand, the finer resolution of\u0000the EFIELD experiment and its ability to capture several harmonics of SR should\u0000provide more robust constraints on Titan's internal structure, especially if\u0000the electrical properties of the ice crust and the atmosphere can be better\u0000constrained.","PeriodicalId":501209,"journal":{"name":"arXiv - PHYS - Earth and Planetary Astrophysics","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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