The Astrophysical Journal Letters最新文献_第4页

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 S255IR NIRS3 (SHEA)热核爆发吸积的光谱调查:I级和II级毫米甲醇微波激射跃迁的发现

The Astrophysical Journal Letters Pub Date : 2023-08-11 DOI: 10.3847/2041-8213/acef1d

Giseon Baek, Jeong-Eun Lee, N. Evans, T. Hirota, Y. Aikawa, Ji-hyun Kang, Jungha Kim, J. Jørgensen

引用次数: 0

CUTE Reveals Escaping Metals in the Upper Atmosphere of the Ultrahot Jupiter WASP-189b 可爱揭示了超热木星WASP-189b上层大气中逃逸的金属

The Astrophysical Journal Letters Pub Date : 2023-08-10 DOI: 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

{"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}

引用次数: 0

Snowflakes in a Furnace: Formation of CO and Dust in a Recurrent Nova Eruption 熔炉里的雪花:在一次经常性新星喷发中CO和尘埃的形成

The Astrophysical Journal Letters Pub Date : 2023-08-05 DOI: 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

{"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}

引用次数: 1

Ultracool Dwarfs Observed with the Spitzer Infrared Spectrograph: Equatorial Latitudes in L Dwarf Atmospheres Are Cloudier 用斯皮策红外光谱仪观察到的超冷矮星:L矮星大气中的赤道纬度更多云

The Astrophysical Journal Letters Pub Date : 2023-08-04 DOI: 10.3847/2041-8213/acec4b

G. Suárez, J. Vos, S. Metchev, J. Faherty, K. Cruz

{"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}

引用次数: 0

Outflowing Helium from a Mature Mini-Neptune 从成熟的迷你海王星流出的氦

The Astrophysical Journal Letters Pub Date : 2023-08-01 DOI: 10.3847/2041-8213/aced51

Michael M. Zhang, F. Dai, J. Bean, H. Knutson, F. Rescigno

引用次数: 0

Statistical Study of Anisotropic Proton Heating in Interplanetary Magnetic Switchbacks Measured by Parker Solar Probe 帕克太阳探测器测量的行星际磁转换中各向异性质子加热的统计研究

The Astrophysical Journal Letters Pub Date : 2023-08-01 DOI: 10.3847/2041-8213/acce9f

Qiaowen Luo, D. Duan, Jiansen He, Xingyu Zhu, D. Verscharen, J. Cui, H. Lai

{"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}

引用次数: 0

Deuterium Escape on Photoevaporating Sub-Neptunes 光蒸发亚海王星上的氘逸出

The Astrophysical Journal Letters Pub Date : 2023-08-01 DOI: 10.3847/2041-8213/acee01

P. Gu, Howard Chen

{"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}

引用次数: 0

Evidence of Stellar Oscillations in the Post-common-envelope Binary Candidate ASASSN-V J205543.90+240033.5 共同包络层后双星候选星ASASSN-V J205543.90+240033.5恒星振荡的证据

The Astrophysical Journal Letters Pub Date : 2023-08-01 DOI: 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

{"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}

引用次数: 0

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 JWST早期发布科学计划Q3D的第一批结果:z = 0.435处尘埃电离红色类星体风的光学和中红外示踪剂的基准比较

The Astrophysical Journal Letters Pub Date : 2023-08-01 DOI: 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

{"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}

引用次数: 0

First Observation of a Double-peaked O i Emission in the Near-infrared Spectrum of an Active Galaxy 在活动星系近红外光谱中首次观测到双峰O i发射

The Astrophysical Journal Letters Pub Date : 2023-08-01 DOI: 10.3847/2041-8213/ace974

Denimara Dias dos Santos, A. Rodríguez-Ardila, S. Panda, M. Marinello

{"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}

引用次数: 1