Pub Date : 2023-08-11DOI: 10.3847/2041-8213/acef1d
Giseon Baek, Jeong-Eun Lee, N. Evans, T. Hirota, Y. Aikawa, Ji-hyun Kang, Jungha Kim, J. Jørgensen
We report the detection of the millimeter CH3OH masers including a new detection of class I (110,11–101,10A) and class II (61,5–52,4E) maser transitions toward the high-mass protostar S255IR NIRS3 in postburst phase. The CH3OH emissions were detected as a mixture of maser and thermal characteristics. We examine the detected transitions using an excitation diagram and local thermodynamic equilibrium model spectra and compare the observed properties with those of thermal lines. Class II CH3OH maser transitions showed distinctive intensity and velocity distributions from those of thermal transitions. Bright, distinct emission components in addition to the fragmented and arc-shaped emissions are only detected in class I CH3OH maser transitions toward southern and western directions from the protostellar position, implying the presence of the slow outflow shocks.
{"title":"Spectral Survey of a Hot Core with an Eruptive Accretion in S255IR NIRS3 (SHEA): The Discovery of Class I and II Millimeter Methanol Maser Transitions","authors":"Giseon Baek, Jeong-Eun Lee, N. Evans, T. Hirota, Y. Aikawa, Ji-hyun Kang, Jungha Kim, J. Jørgensen","doi":"10.3847/2041-8213/acef1d","DOIUrl":"https://doi.org/10.3847/2041-8213/acef1d","url":null,"abstract":"We report the detection of the millimeter CH3OH masers including a new detection of class I (110,11–101,10A) and class II (61,5–52,4E) maser transitions toward the high-mass protostar S255IR NIRS3 in postburst phase. The CH3OH emissions were detected as a mixture of maser and thermal characteristics. We examine the detected transitions using an excitation diagram and local thermodynamic equilibrium model spectra and compare the observed properties with those of thermal lines. Class II CH3OH maser transitions showed distinctive intensity and velocity distributions from those of thermal transitions. Bright, distinct emission components in addition to the fragmented and arc-shaped emissions are only detected in class I CH3OH maser transitions toward southern and western directions from the protostellar position, implying the presence of the slow outflow shocks.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130701741","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}
Pub Date : 2023-08-10DOI: 10.3847/2041-8213/acef1c
A. Sreejith, K. France, L. Fossati, T. Koskinen, A. Egan, P. Cauley, P. Cubillos, S. Ambily, Chenliang Huang, P. Lavvas, B. Fleming, J. Désert, N. Nell, P. Petit, A. Vidotto
Ultraviolet observations of ultrahot Jupiters, exoplanets with temperatures over 2000 K, provide us with an opportunity to investigate if and how atmospheric escape shapes their upper atmosphere. Near-ultraviolet transit spectroscopy offers a unique tool to study this process owing to the presence of strong metal lines and a bright photospheric continuum as the light source against which the absorbing gas is observed. WASP-189b is one of the hottest planets discovered to date, with a dayside temperature of about 3400 K orbiting a bright A-type star. We present the first near-ultraviolet observations of WASP-189b, acquired with the Colorado Ultraviolet Transit Experiment (CUTE). CUTE is a 6U NASA-funded ultraviolet spectroscopy mission, dedicated to monitoring short-period transiting planets. WASP-189b was one of the CUTE early science targets and was observed during three consecutive transits in 2022 March. We present an analysis of the CUTE observations and results demonstrating near-ultraviolet (2500–3300 Å) broadband transit depth ( 1.08−0.08+0.08% ) of about twice the visual transit depth indicating that the planet has an extended, hot upper atmosphere with a temperature of about 15,000 K and a moderate mass-loss rate of about 4 × 108 kg s−1. We observe absorption by Mg ii lines (R p /R s of 0.212−0.061+0.038 ) beyond the Roche lobe at >4σ significance in the transmission spectrum at a resolution of 10 Å, while at lower resolution (100 Å), we observe a quasi-continuous absorption signal consistent with a “forest” of low-ionization metal absorption dominated by Fe ii. The results suggest an upper atmospheric temperature (∼15,000 K), higher than that predicted by current state-of-the-art hydrodynamic models.
对温度超过2000 K的超热木星(系外行星)的紫外线观测为我们提供了一个研究大气逃逸是否以及如何塑造其上层大气的机会。近紫外传输光谱为研究这一过程提供了一个独特的工具，因为存在强金属谱线和明亮的光球连续体作为观察吸收气体的光源。WASP-189b是迄今为止发现的最热的行星之一，它的白天温度约为3400 K，围绕一颗明亮的a型恒星运行。我们提出了第一次对WASP-189b的近紫外观测，这是由科罗拉多紫外过境实验(CUTE)获得的。CUTE是美国宇航局资助的一项6U紫外光谱任务，致力于监测短周期凌日行星。WASP-189b是CUTE早期的科学目标之一，在2022年3月连续三次凌日期间被观测到。我们对CUTE观测结果进行了分析，结果表明近紫外(2500-3300 Å)宽带传输深度(1.08−0.08+0.08%)约为视觉传输深度的两倍，表明该行星有一个扩展的、热的上层大气，温度约为15,000 K，质量损失率约为4 × 108 kg s−1。在分辨率为10 Å的透射光谱中，我们观察到Mg ii谱线(R p /R s为0.212−0.061+0.038)在罗氏波叶之外的吸收，在>4σ显著性，而在较低分辨率(100 Å)下，我们观察到一个准连续的吸收信号，与以Fe ii为主的低电离金属吸收“森林”相一致。结果表明，上层大气温度(~ 15,000 K)比目前最先进的流体动力学模型预测的要高。
{"title":"CUTE Reveals Escaping Metals in the Upper Atmosphere of the Ultrahot Jupiter WASP-189b","authors":"A. Sreejith, K. France, L. Fossati, T. Koskinen, A. Egan, P. Cauley, P. Cubillos, S. Ambily, Chenliang Huang, P. Lavvas, B. Fleming, J. Désert, N. Nell, P. Petit, A. Vidotto","doi":"10.3847/2041-8213/acef1c","DOIUrl":"https://doi.org/10.3847/2041-8213/acef1c","url":null,"abstract":"Ultraviolet observations of ultrahot Jupiters, exoplanets with temperatures over 2000 K, provide us with an opportunity to investigate if and how atmospheric escape shapes their upper atmosphere. Near-ultraviolet transit spectroscopy offers a unique tool to study this process owing to the presence of strong metal lines and a bright photospheric continuum as the light source against which the absorbing gas is observed. WASP-189b is one of the hottest planets discovered to date, with a dayside temperature of about 3400 K orbiting a bright A-type star. We present the first near-ultraviolet observations of WASP-189b, acquired with the Colorado Ultraviolet Transit Experiment (CUTE). CUTE is a 6U NASA-funded ultraviolet spectroscopy mission, dedicated to monitoring short-period transiting planets. WASP-189b was one of the CUTE early science targets and was observed during three consecutive transits in 2022 March. We present an analysis of the CUTE observations and results demonstrating near-ultraviolet (2500–3300 Å) broadband transit depth ( 1.08−0.08+0.08% ) of about twice the visual transit depth indicating that the planet has an extended, hot upper atmosphere with a temperature of about 15,000 K and a moderate mass-loss rate of about 4 × 108 kg s−1. We observe absorption by Mg ii lines (R p /R s of 0.212−0.061+0.038 ) beyond the Roche lobe at >4σ significance in the transmission spectrum at a resolution of 10 Å, while at lower resolution (100 Å), we observe a quasi-continuous absorption signal consistent with a “forest” of low-ionization metal absorption dominated by Fe ii. The results suggest an upper atmospheric temperature (∼15,000 K), higher than that predicted by current state-of-the-art hydrodynamic models.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122635286","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}
Pub Date : 2023-08-05DOI: 10.3847/2041-8213/acf0c4
D. Banerjee, C. Woodward, V. Joshi, A. Evans, F. Walter, G. H. Marion, E. Hsiao, N. Ashok, R. Gehrz, S. Starrfield
We report the detection of carbon monoxide (CO) and dust, formed under hostile conditions, in recurrent nova V745 Sco about 8.7 days after its 2014 outburst. The formation of molecules or dust has not been recorded previously in the ejecta of a recurrent nova. The mass and temperature of the CO and dust are estimated to be T CO = 2250 ± 250 K, M CO = (1–5) × 10−8 M ⊙, and T dust = 1000 ± 50 K, M dust ∼ 10−8–10−9 M ⊙, respectively. At the time of their detection, the shocked gas was at a high temperature of ∼107 K as evidenced by the presence of coronal lines. The ejecta were simultaneously irradiated by a large flux of soft X-ray radiation from the central white dwarf. Molecules and dust are not expected to form and survive in such harsh conditions; they are like snowflakes in a furnace. However, it has been posited in other studies that, as the nova ejecta plow through the red giant's wind, a region exists between the forward and reverse shocks that is cool, dense and clumpy where the dust and CO could likely form. We speculate that this site may also be a region of particle acceleration, thereby contributing to the generation of γ-rays.
我们报告了在2014年爆发后约8.7天，在复发新星V745 Sco中检测到在恶劣条件下形成的一氧化碳(CO)和尘埃。分子或尘埃的形成以前没有记录在一颗复发新星的喷出物中。CO和尘埃的质量和温度估计分别为T CO = 2250±250 K, M CO = (1-5) × 10−8 M⊙，T dust = 1000±50 K, M dust = 10−8 - 10−9 M⊙。在他们被探测到的时候，受冲击的气体处于~ 107 K的高温，日冕线的存在证明了这一点。喷射物同时受到来自中央白矮星的大量软x射线辐射的照射。分子和灰尘不可能在如此恶劣的条件下形成和存活;他们就像火炉里的雪花。然而，在其他研究中已经假设，当新星喷出物穿过红巨星的风时，在正向和反向激波之间存在一个区域，该区域温度低，密度大，块状，可能形成尘埃和CO。我们推测这个位置也可能是粒子加速的区域，从而有助于γ射线的产生。
{"title":"Snowflakes in a Furnace: Formation of CO and Dust in a Recurrent Nova Eruption","authors":"D. Banerjee, C. Woodward, V. Joshi, A. Evans, F. Walter, G. H. Marion, E. Hsiao, N. Ashok, R. Gehrz, S. Starrfield","doi":"10.3847/2041-8213/acf0c4","DOIUrl":"https://doi.org/10.3847/2041-8213/acf0c4","url":null,"abstract":"We report the detection of carbon monoxide (CO) and dust, formed under hostile conditions, in recurrent nova V745 Sco about 8.7 days after its 2014 outburst. The formation of molecules or dust has not been recorded previously in the ejecta of a recurrent nova. The mass and temperature of the CO and dust are estimated to be T CO = 2250 ± 250 K, M CO = (1–5) × 10−8 M ⊙, and T dust = 1000 ± 50 K, M dust ∼ 10−8–10−9 M ⊙, respectively. At the time of their detection, the shocked gas was at a high temperature of ∼107 K as evidenced by the presence of coronal lines. The ejecta were simultaneously irradiated by a large flux of soft X-ray radiation from the central white dwarf. Molecules and dust are not expected to form and survive in such harsh conditions; they are like snowflakes in a furnace. However, it has been posited in other studies that, as the nova ejecta plow through the red giant's wind, a region exists between the forward and reverse shocks that is cool, dense and clumpy where the dust and CO could likely form. We speculate that this site may also be a region of particle acceleration, thereby contributing to the generation of γ-rays.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131606273","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}
Pub Date : 2023-08-04DOI: 10.3847/2041-8213/acec4b
G. Suárez, J. Vos, S. Metchev, J. Faherty, K. Cruz
We report direct observational evidence for a latitudinal dependence of dust cloud opacity in ultracool dwarfs, indicating that equatorial latitudes are cloudier than polar latitudes. These results are based on a strong positive correlation between the viewing geometry and the mid-infrared silicate absorption strength in mid-L dwarfs using mid-infrared spectra from the Spitzer Space Telescope and spin axis inclination measurements from available information in the literature. We confirmed that the infrared color anomalies of L dwarfs positively correlate with dust cloud opacity and viewing geometry, where redder objects are inclined equator-on and exhibit more opaque dust clouds, while dwarfs viewed at higher latitudes and with more transparent clouds are bluer. These results show the relevance of viewing geometry to explain the appearance of brown dwarfs and provide insight into the spectral diversity observed in substellar and planetary atmospheres. We also find a hint that dust clouds at similar latitudes may have higher opacity in low-surface gravity dwarfs than in higher-gravity objects.
{"title":"Ultracool Dwarfs Observed with the Spitzer Infrared Spectrograph: Equatorial Latitudes in L Dwarf Atmospheres Are Cloudier","authors":"G. Suárez, J. Vos, S. Metchev, J. Faherty, K. Cruz","doi":"10.3847/2041-8213/acec4b","DOIUrl":"https://doi.org/10.3847/2041-8213/acec4b","url":null,"abstract":"We report direct observational evidence for a latitudinal dependence of dust cloud opacity in ultracool dwarfs, indicating that equatorial latitudes are cloudier than polar latitudes. These results are based on a strong positive correlation between the viewing geometry and the mid-infrared silicate absorption strength in mid-L dwarfs using mid-infrared spectra from the Spitzer Space Telescope and spin axis inclination measurements from available information in the literature. We confirmed that the infrared color anomalies of L dwarfs positively correlate with dust cloud opacity and viewing geometry, where redder objects are inclined equator-on and exhibit more opaque dust clouds, while dwarfs viewed at higher latitudes and with more transparent clouds are bluer. These results show the relevance of viewing geometry to explain the appearance of brown dwarfs and provide insight into the spectral diversity observed in substellar and planetary atmospheres. We also find a hint that dust clouds at similar latitudes may have higher opacity in low-surface gravity dwarfs than in higher-gravity objects.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127999996","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}
Pub Date : 2023-08-01DOI: 10.3847/2041-8213/aced51
Michael M. Zhang, F. Dai, J. Bean, H. Knutson, F. Rescigno
We announce the detection of escaping helium from TOI 2134b, a mini-Neptune a few gigayears old. The average in-transit absorption spectrum shows a peak of 0.37% ± 0.05% and an equivalent width of W avg = 3.3 ± 0.3 mÅ. Among all planets with helium detections, TOI 2134b is the only mature mini-Neptune, has the smallest helium signal, and experiences the lowest X-ray and ultraviolet (XUV) flux. Putting TOI 2134b in the context of all other helium detections, we report the detection of a strong (p = 3.0 × 10−5) and theoretically expected correlation between F XUV/ρ XUV (proportional to the energy-limited mass-loss rate) and R * W avg (roughly proportional to the observationally inferred mass-loss rate). Here W avg is the equivalent width of the helium absorption, and ρ XUV is the density of the planet within the XUV photosphere, but the correlation is similarly strong if we use the optical photosphere. Having the lowest value on both axes, TOI 2134b anchors the relation. We encourage further observations to fill in the missing regions of this parameter space and improve estimates of F XUV.
{"title":"Outflowing Helium from a Mature Mini-Neptune","authors":"Michael M. Zhang, F. Dai, J. Bean, H. Knutson, F. Rescigno","doi":"10.3847/2041-8213/aced51","DOIUrl":"https://doi.org/10.3847/2041-8213/aced51","url":null,"abstract":"We announce the detection of escaping helium from TOI 2134b, a mini-Neptune a few gigayears old. The average in-transit absorption spectrum shows a peak of 0.37% ± 0.05% and an equivalent width of W avg = 3.3 ± 0.3 mÅ. Among all planets with helium detections, TOI 2134b is the only mature mini-Neptune, has the smallest helium signal, and experiences the lowest X-ray and ultraviolet (XUV) flux. Putting TOI 2134b in the context of all other helium detections, we report the detection of a strong (p = 3.0 × 10−5) and theoretically expected correlation between F XUV/ρ XUV (proportional to the energy-limited mass-loss rate) and R * W avg (roughly proportional to the observationally inferred mass-loss rate). Here W avg is the equivalent width of the helium absorption, and ρ XUV is the density of the planet within the XUV photosphere, but the correlation is similarly strong if we use the optical photosphere. Having the lowest value on both axes, TOI 2134b anchors the relation. We encourage further observations to fill in the missing regions of this parameter space and improve estimates of F XUV.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130014936","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}
Pub Date : 2023-08-01DOI: 10.3847/2041-8213/acce9f
Qiaowen Luo, D. Duan, Jiansen He, Xingyu Zhu, D. Verscharen, J. Cui, H. Lai
Magnetic switchbacks, which are large angular deflections of the interplanetary magnetic field, are frequently observed by Parker Solar Probe (PSP) in the inner heliosphere. Magnetic switchbacks are believed to play an important role in the heating of the solar corona and the solar wind as well as the acceleration of the solar wind in the inner heliosphere. Here, we analyze magnetic field data and plasma data measured by PSP during its second and fourth encounters, and select 71 switchback events with reversals of the radial component of the magnetic field at times of unchanged electron-strahl pitch angles. We investigate the anisotropic thermal kinetic properties of plasma during switchbacks in a statistical study of the measured proton temperatures in the parallel and perpendicular directions as well as proton density and specific proton fluid entropy. We apply the “genetic algorithm” method to directly fit the measured velocity distribution functions in field-aligned coordinates using a two-component bi-Maxwellian distribution function. We find that the protons in most switchback events are hotter than the ambient plasma outside the switchbacks, with characteristics of parallel and perpendicular heating. Specifically, significant parallel and perpendicular temperature increases are seen for 45 and 62 of the 71 events, respectively. We find that the density of most switchback events decreases rather than increases, which indicates that proton heating inside the switchbacks is not caused by adiabatic compression, but is probably generated by nonadiabatic heating caused by field–particle interactions. Accordingly, the proton fluid entropy is greater inside the switchbacks than in the ambient solar wind.
{"title":"Statistical Study of Anisotropic Proton Heating in Interplanetary Magnetic Switchbacks Measured by Parker Solar Probe","authors":"Qiaowen Luo, D. Duan, Jiansen He, Xingyu Zhu, D. Verscharen, J. Cui, H. Lai","doi":"10.3847/2041-8213/acce9f","DOIUrl":"https://doi.org/10.3847/2041-8213/acce9f","url":null,"abstract":"Magnetic switchbacks, which are large angular deflections of the interplanetary magnetic field, are frequently observed by Parker Solar Probe (PSP) in the inner heliosphere. Magnetic switchbacks are believed to play an important role in the heating of the solar corona and the solar wind as well as the acceleration of the solar wind in the inner heliosphere. Here, we analyze magnetic field data and plasma data measured by PSP during its second and fourth encounters, and select 71 switchback events with reversals of the radial component of the magnetic field at times of unchanged electron-strahl pitch angles. We investigate the anisotropic thermal kinetic properties of plasma during switchbacks in a statistical study of the measured proton temperatures in the parallel and perpendicular directions as well as proton density and specific proton fluid entropy. We apply the “genetic algorithm” method to directly fit the measured velocity distribution functions in field-aligned coordinates using a two-component bi-Maxwellian distribution function. We find that the protons in most switchback events are hotter than the ambient plasma outside the switchbacks, with characteristics of parallel and perpendicular heating. Specifically, significant parallel and perpendicular temperature increases are seen for 45 and 62 of the 71 events, respectively. We find that the density of most switchback events decreases rather than increases, which indicates that proton heating inside the switchbacks is not caused by adiabatic compression, but is probably generated by nonadiabatic heating caused by field–particle interactions. Accordingly, the proton fluid entropy is greater inside the switchbacks than in the ambient solar wind.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129602642","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}
Pub Date : 2023-08-01DOI: 10.3847/2041-8213/acee01
P. Gu, Howard Chen
We investigate the evolution of the deuterium-to-hydrogen (D/H) mass ratio driven by EUV photoevaporation of hydrogen-rich atmospheres of close-in sub-Neptunes around solar-type stars. For the first time, the diffusion-limited approach in conjunction with energy-limited photoevaporation is considered in evaluating deuterium escape from evolving exoplanet H/He envelopes. We find that the planets with smaller initial gas envelopes and thus smaller sizes can lead to weaker atmospheric escape, which facilitates hydrogen–deuterium fractionation. Specifically, in our grid of simulations with a low envelope mass fraction of less than 0.005, a low-mass sub-Neptune (4–5 M ⊕) at about 0.25–0.4 au or a high-mass sub-Neptune (10–15 M ⊕) at about 0.1–0.25 au can increase the D/H values by greater than 20% over 7.5 Gyr. Akin to the helium-enhanced envelopes of sub-Neptunes due to photoevaporating escape, the planets along the upper boundary of the radius valley are the best targets to detect high D/H ratios. The ratio can rise by a factor of ≲1.65 within 7.5 Gyr in our grid of evolutionary calculations. The D/H ratio is expected to be higher in thinner envelopes as long as the planets do not become bare rocky cores.
{"title":"Deuterium Escape on Photoevaporating Sub-Neptunes","authors":"P. Gu, Howard Chen","doi":"10.3847/2041-8213/acee01","DOIUrl":"https://doi.org/10.3847/2041-8213/acee01","url":null,"abstract":"We investigate the evolution of the deuterium-to-hydrogen (D/H) mass ratio driven by EUV photoevaporation of hydrogen-rich atmospheres of close-in sub-Neptunes around solar-type stars. For the first time, the diffusion-limited approach in conjunction with energy-limited photoevaporation is considered in evaluating deuterium escape from evolving exoplanet H/He envelopes. We find that the planets with smaller initial gas envelopes and thus smaller sizes can lead to weaker atmospheric escape, which facilitates hydrogen–deuterium fractionation. Specifically, in our grid of simulations with a low envelope mass fraction of less than 0.005, a low-mass sub-Neptune (4–5 M ⊕) at about 0.25–0.4 au or a high-mass sub-Neptune (10–15 M ⊕) at about 0.1–0.25 au can increase the D/H values by greater than 20% over 7.5 Gyr. Akin to the helium-enhanced envelopes of sub-Neptunes due to photoevaporating escape, the planets along the upper boundary of the radius valley are the best targets to detect high D/H ratios. The ratio can rise by a factor of ≲1.65 within 7.5 Gyr in our grid of evolutionary calculations. The D/H ratio is expected to be higher in thinner envelopes as long as the planets do not become bare rocky cores.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123205821","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}
Pub Date : 2023-08-01DOI: 10.3847/2041-8213/acec4c
J. Takata, A. Kong, X. Wang, F. Song, J. Mao, X. Hou, C. Hu, -. Lin, K. L. Li, C. Hui
ASASSN-V J205543.90+240033.5 (ASJ2055) is a possible post-common-envelope binary system. Its optical photometric data show an orbital variation of about 0.52 days and a fast period modulation of P 0 ∼ 9.77 minutes, whose origin is unknown. In this Letter, we report evidence of the stellar oscillation of the companion star as the origin of the fast period modulation. We analyze the photometric data taken by the Transiting Exoplanet Survey Satellite, the Liverpool Telescope, and the Lulin One-meter Telescope. It is found that the period of the 9.77 minutes signal measured in 2022 August is significantly shorter than that in 2021 July/August, and the magnitude of the change is of the order of ∣△P 0∣/P 0 ∼ 0.0008(4). Such a large variation will be incompatible with the scenario of the white dwarf (WD) spin as the origin of the 9.77 minutes periodic modulation. We suggest that the fast periodic signal is related to the emission from the irradiated companion star rather than that of the WD. Using existing photometric data covering a wide wavelength range, we estimate that the hot WD in ASJ2055 has a temperature of T eff ∼ 80,000 K and is heating the oscillating M-type main-sequence star with T eff ∼ 3500 K on its unirradiated surface. The stellar oscillation of the M-type main-sequence star has been predicted in theoretical studies, but no observational confirmation has been done. ASJ2055, therefore, has the potential to be a unique laboratory for investigating the stellar oscillation of an M-type main-sequence star and the heating effect on stellar oscillation.
{"title":"Evidence of Stellar Oscillations in the Post-common-envelope Binary Candidate ASASSN-V J205543.90+240033.5","authors":"J. Takata, A. Kong, X. Wang, F. Song, J. Mao, X. Hou, C. Hu, -. Lin, K. L. Li, C. Hui","doi":"10.3847/2041-8213/acec4c","DOIUrl":"https://doi.org/10.3847/2041-8213/acec4c","url":null,"abstract":"ASASSN-V J205543.90+240033.5 (ASJ2055) is a possible post-common-envelope binary system. Its optical photometric data show an orbital variation of about 0.52 days and a fast period modulation of P 0 ∼ 9.77 minutes, whose origin is unknown. In this Letter, we report evidence of the stellar oscillation of the companion star as the origin of the fast period modulation. We analyze the photometric data taken by the Transiting Exoplanet Survey Satellite, the Liverpool Telescope, and the Lulin One-meter Telescope. It is found that the period of the 9.77 minutes signal measured in 2022 August is significantly shorter than that in 2021 July/August, and the magnitude of the change is of the order of ∣△P 0∣/P 0 ∼ 0.0008(4). Such a large variation will be incompatible with the scenario of the white dwarf (WD) spin as the origin of the 9.77 minutes periodic modulation. We suggest that the fast periodic signal is related to the emission from the irradiated companion star rather than that of the WD. Using existing photometric data covering a wide wavelength range, we estimate that the hot WD in ASJ2055 has a temperature of T eff ∼ 80,000 K and is heating the oscillating M-type main-sequence star with T eff ∼ 3500 K on its unirradiated surface. The stellar oscillation of the M-type main-sequence star has been predicted in theoretical studies, but no observational confirmation has been done. ASJ2055, therefore, has the potential to be a unique laboratory for investigating the stellar oscillation of an M-type main-sequence star and the heating effect on stellar oscillation.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132982707","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}
Pub Date : 2023-08-01DOI: 10.3847/2041-8213/aced85
D. Rupke, D. Wylezalek, N. Zakamska, S. Veilleux, C. Bertemes, Yuzo Ishikawa, W. Liu, S. Sankar, A. Vayner, Hui Xian Grace Lim, R. McCrory, G. Murphree, L. Whitesell, Lu Shen, Guilin Liu, J. Barrera-Ballesteros, Hsiao-Wen Chen, N. Diachenko, A. Goulding, J. Greene, K. Hainline, F. Hamann, T. Heckman, S. Johnson, D. Lutz, N. Lützgendorf, V. Mainieri, N. Nesvadba, P. Ogle, E. Sturm
The [O iii] 5007 Å emission line is the most common tracer of warm, ionized outflows in active galactic nuclei across cosmic time. JWST newly allows us to use mid-IR spectral features at both high spatial and spectral resolution to probe these same winds. Here we present a comparison of ground-based, seeing-limited [O iii] and space-based, diffraction-limited [S iv] 10.51 μm maps of the powerful, kiloparsec-scale outflow in the Type 1 red quasar SDSS J110648.32+480712.3. The JWST data are from the Mid-InfraRed Instrument. There is a close match in resolution between the data sets (∼0.″6), in ionization potential of the O+2 and S+3 ions (35 eV) and in line sensitivity (1–2 × 10−17 erg s−1 cm−2 arcsec−2). The [O iii] and [S iv] line shapes match in velocity and line width over much of the 20 kpc outflowing nebula, and [S iv] is the brightest line in the rest-frame 3.5–19.5 μm range, demonstrating its usefulness as a mid-IR probe of quasar outflows. [O iii] is nevertheless intrinsically brighter and provides better contrast with the point-source continuum, which is strong in the mid-IR. There is a strong anticorrelation of [O iii]/[S iv] with average velocity, which is consistent with a scenario of differential obscuration between the approaching (blueshifted) and receding (redshifted) sides of the flow. The dust in the wind may also obscure the central quasar, consistent with models that attribute red quasar extinction to dusty winds.
{"title":"First Results from the JWST Early Release Science Program Q3D: Benchmark Comparison of Optical and Mid-infrared Tracers of a Dusty, Ionized Red Quasar Wind at z = 0.435","authors":"D. Rupke, D. Wylezalek, N. Zakamska, S. Veilleux, C. Bertemes, Yuzo Ishikawa, W. Liu, S. Sankar, A. Vayner, Hui Xian Grace Lim, R. McCrory, G. Murphree, L. Whitesell, Lu Shen, Guilin Liu, J. Barrera-Ballesteros, Hsiao-Wen Chen, N. Diachenko, A. Goulding, J. Greene, K. Hainline, F. Hamann, T. Heckman, S. Johnson, D. Lutz, N. Lützgendorf, V. Mainieri, N. Nesvadba, P. Ogle, E. Sturm","doi":"10.3847/2041-8213/aced85","DOIUrl":"https://doi.org/10.3847/2041-8213/aced85","url":null,"abstract":"The [O iii] 5007 Å emission line is the most common tracer of warm, ionized outflows in active galactic nuclei across cosmic time. JWST newly allows us to use mid-IR spectral features at both high spatial and spectral resolution to probe these same winds. Here we present a comparison of ground-based, seeing-limited [O iii] and space-based, diffraction-limited [S iv] 10.51 μm maps of the powerful, kiloparsec-scale outflow in the Type 1 red quasar SDSS J110648.32+480712.3. The JWST data are from the Mid-InfraRed Instrument. There is a close match in resolution between the data sets (∼0.″6), in ionization potential of the O+2 and S+3 ions (35 eV) and in line sensitivity (1–2 × 10−17 erg s−1 cm−2 arcsec−2). The [O iii] and [S iv] line shapes match in velocity and line width over much of the 20 kpc outflowing nebula, and [S iv] is the brightest line in the rest-frame 3.5–19.5 μm range, demonstrating its usefulness as a mid-IR probe of quasar outflows. [O iii] is nevertheless intrinsically brighter and provides better contrast with the point-source continuum, which is strong in the mid-IR. There is a strong anticorrelation of [O iii]/[S iv] with average velocity, which is consistent with a scenario of differential obscuration between the approaching (blueshifted) and receding (redshifted) sides of the flow. The dust in the wind may also obscure the central quasar, consistent with models that attribute red quasar extinction to dusty winds.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127885888","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}
Pub Date : 2023-08-01DOI: 10.3847/2041-8213/ace974
Denimara Dias dos Santos, A. Rodríguez-Ardila, S. Panda, M. Marinello
Double-peaked profiles associated with the broad-line region (BLR) of active galactic nuclei (AGNs) are regarded as the clearest evidence of the presence of an accretion disk. They are most commonly detected by means of optical spectroscopy in the Balmer lines and in the Mg ii λ2798 ultraviolet line. Here, we report the first unambiguous detection of a double-peak broad emission line associated with the O i λ11297 emission line in the near-infrared (NIR) in the local Seyfert 1 galaxy III Zw 002. Additionally, we detect simultaneously in the spectrum the double-peak emission in the Paα line and very likely in the He i λ10830. This is the first time that several broad double-peaked NIR emission lines have been detected simultaneously. The double-peaked profiles are fit using a disk-based model, with an additional Gaussian component attributed to nondisk clouds, which represents the classical BLR. Our results obtained from the fits reveal important parameters, such as disk inclination and geometry. From the double-peaked profile fits, we suggest that the BLR in III Zw 002 has a disk-like geometry, as it extends up to the outer edge of the BLR.
与活动星系核(agn)的宽线区域(BLR)相关的双峰剖面被认为是吸积盘存在的最清晰证据。它们最常被光谱学上的巴尔默谱线和mgii λ2798紫外谱线探测到。在这里，我们报告了在本地Seyfert 1星系III Zw 002的近红外(NIR)中首次明确探测到与O i λ11297发射线相关的双峰宽发射线。此外，我们在光谱中同时检测到Paα线和He i λ10830线的双峰发射。这是第一次同时探测到几条宽双峰近红外发射线。使用基于磁盘的模型拟合双峰剖面，其中附加的高斯分量归因于非磁盘云，这代表了经典的BLR。我们从拟合中得到的结果揭示了重要的参数，如圆盘倾角和几何形状。从双峰剖面拟合来看，我们认为III Zw 002中的BLR具有圆盘状几何形状，因为它延伸到BLR的外缘。
{"title":"First Observation of a Double-peaked O i Emission in the Near-infrared Spectrum of an Active Galaxy","authors":"Denimara Dias dos Santos, A. Rodríguez-Ardila, S. Panda, M. Marinello","doi":"10.3847/2041-8213/ace974","DOIUrl":"https://doi.org/10.3847/2041-8213/ace974","url":null,"abstract":"Double-peaked profiles associated with the broad-line region (BLR) of active galactic nuclei (AGNs) are regarded as the clearest evidence of the presence of an accretion disk. They are most commonly detected by means of optical spectroscopy in the Balmer lines and in the Mg ii λ2798 ultraviolet line. Here, we report the first unambiguous detection of a double-peak broad emission line associated with the O i λ11297 emission line in the near-infrared (NIR) in the local Seyfert 1 galaxy III Zw 002. Additionally, we detect simultaneously in the spectrum the double-peak emission in the Paα line and very likely in the He i λ10830. This is the first time that several broad double-peaked NIR emission lines have been detected simultaneously. The double-peaked profiles are fit using a disk-based model, with an additional Gaussian component attributed to nondisk clouds, which represents the classical BLR. Our results obtained from the fits reveal important parameters, such as disk inclination and geometry. From the double-peaked profile fits, we suggest that the BLR in III Zw 002 has a disk-like geometry, as it extends up to the outer edge of the BLR.","PeriodicalId":179976,"journal":{"name":"The Astrophysical Journal Letters","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126017285","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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