The Astrophysical Journal最新文献_第10页

Evidence for Core–Core Collision in Barnard 68 巴纳德68号核-核碰撞的证据

The Astrophysical Journal Pub Date : 2025-05-26 DOI: 10.3847/1538-4357/add326

Dalei Li, Christian Henkel, Alexander Kraus, Xindi Tang, Willem Baan, Jarken Esimbek, Ke Wang, Gang Wu, Tie Liu, Andrej M. Sobolev, Jianjun Zhou, Yuxin He and Toktarkhan Komesh

{"title":"Evidence for Core–Core Collision in Barnard 68","authors":"Dalei Li, Christian Henkel, Alexander Kraus, Xindi Tang, Willem Baan, Jarken Esimbek, Ke Wang, Gang Wu, Tie Liu, Andrej M. Sobolev, Jianjun Zhou, Yuxin He and Toktarkhan Komesh","doi":"10.3847/1538-4357/add326","DOIUrl":"https://doi.org/10.3847/1538-4357/add326","url":null,"abstract":"The prestellar core Barnard 68 (B68) is a prototypical source to study the initial conditions and chemical processes of star formation. A previous numerical simulation suggested the southeastern bullet is impacting on the main body of B68. In order to obtain more observational evidence, mapping observations of the ground state SO (10–01) emission line at 30 GHz were made with the Effelsberg 100 m telescope. Based on the velocity field and channel maps derived from SO, three velocity components were clearly detected. The velocity field of the main body indicates rotation and is well fitted by a solid-body rotation model. The measured radial velocity difference between the bullet and the main core is about 0.4 km s−1, which is almost equal to the velocity obtained by the previous numerical simulation. Therefore, the bullet is most likely impacting on the rotating main body of B68. A 1D spherical non–local thermodynamic equilibrium Monte Carlo radiation transfer RATRAN code is performed to derive the radial abundance profile of SO by analyzing the observed velocity-integrated intensity. SO is depleted inside a 60″ (0.02 pc) radius from the core. The abundance stays constant at 2.0 × 10−9 for radii larger than 60″ from the center of the main core. The abundance is enhanced at the interface of the bullet and the main core, indicating that shock waves were produced by the collision between the bullet and the main core. In conclusion, based on the kinematical and chemical analysis, our observational results support the previously proposed core–core collision scenario in B68.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144153555","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

The Kinematic Signature of the Warp and Waves in the Milky Way Disk 银河系盘中翘曲和波的运动特征

The Astrophysical Journal Pub Date : 2025-05-26 DOI: 10.3847/1538-4357/add141

Weixiang Sun, Han Shen, Biwei Jiang and Xiaowei Liu

引用次数: 0

Anisotropic Particle Acceleration in Alfvénic Turbulence 阿尔夫萨奇湍流中的各向异性粒子加速

The Astrophysical Journal Pub Date : 2025-05-26 DOI: 10.3847/1538-4357/add147

Cristian Vega, Stanislav Boldyrev and Vadim Roytershteyn

引用次数: 0

Model-independent Determination of the Tidal Deformability of a 1.4 M ⊙ Neutron Star from Gravitational-wave Measurements 基于引力波测量的一颗1.4 M⊙中子星潮汐变形能力的独立模型测定

The Astrophysical Journal Pub Date : 2025-05-26 DOI: 10.3847/1538-4357/add5ef

Chun Huang

引用次数: 0

The JCMT BISTRO-3 Survey: Variation of Magnetic Field Orientations on Parsec and Subparsec Scales in the Massive Star-forming Region G28.34+0.06 JCMT BISTRO-3巡天：大质量恒星形成区G28.34+0.06的秒差距和亚秒差距尺度上磁场方向的变化

The Astrophysical Journal Pub Date : 2025-05-26 DOI: 10.3847/1538-4357/adce80

Jihye Hwang, Kate Pattle, Chang Won Lee, Janik Karoly, Kee-Tae Kim, Jongsoo Kim, Junhao Liu, Keping Qiu, A-Ran Lyo, David Eden, Patrick M. Koch, Doris Arzoumanian, Ekta Sharma, Frédérick Poidevin, Doug Johnstone, Simon Coudé, Mehrnoosh Tahani, Derek Ward-Thompson, Archana Soam, Ji-hyun Kang, Thiem Hoang, Woojin Kwon, Nguyen Bich Ngoc, Eun Jung Chung, Tyler L. Bourke, Takashi Onaka, Florian Kirchschlager, Motohide Tamura, Jungmi Kwon, Xindi Tang, Eswaraiah Chakali, Tie Liu, Pierre Bastien, Ray S. Furuya, Shih-Ping Lai, Sheng-Jun Lin, Jia-Wei Wang and David Berry

{"title":"The JCMT BISTRO-3 Survey: Variation of Magnetic Field Orientations on Parsec and Subparsec Scales in the Massive Star-forming Region G28.34+0.06","authors":"Jihye Hwang, Kate Pattle, Chang Won Lee, Janik Karoly, Kee-Tae Kim, Jongsoo Kim, Junhao Liu, Keping Qiu, A-Ran Lyo, David Eden, Patrick M. Koch, Doris Arzoumanian, Ekta Sharma, Frédérick Poidevin, Doug Johnstone, Simon Coudé, Mehrnoosh Tahani, Derek Ward-Thompson, Archana Soam, Ji-hyun Kang, Thiem Hoang, Woojin Kwon, Nguyen Bich Ngoc, Eun Jung Chung, Tyler L. Bourke, Takashi Onaka, Florian Kirchschlager, Motohide Tamura, Jungmi Kwon, Xindi Tang, Eswaraiah Chakali, Tie Liu, Pierre Bastien, Ray S. Furuya, Shih-Ping Lai, Sheng-Jun Lin, Jia-Wei Wang and David Berry","doi":"10.3847/1538-4357/adce80","DOIUrl":"https://doi.org/10.3847/1538-4357/adce80","url":null,"abstract":"Magnetic fields play a significant role in star-forming processes on core to clump scales. We investigate magnetic field orientations and strengths in the massive star-forming clump P2 within the filamentary infrared dark cloud G28.34+0.06 using dust polarization observations made using SCUBA-2/POL-2 on the James Clerk Maxwell Telescope (JCMT) as part of the B-field In STar-forming Region Observations (or BISTRO) survey. We compare the magnetic field orientations at the clump scale of ∼2 pc from these JCMT observations with those at the core scale of ∼0.2 pc from archival Atacama Large Millimeter/submillimeter Array data, finding that the magnetic field orientations on these two different scales are perpendicular to one another. We estimate the distribution of magnetic field strengths, which range from 50 to 430 μG over the clump. The region forming the core shows the highest magnetic field strength. We also obtain the distribution of mass-to-flux ratios across the clump. In the region surrounding the core, the mass-to-flux ratio is larger than 1, which indicates that the magnetic field strength is insufficient to support the region against gravitational collapse. Therefore, the change in the magnetic field orientation from clump to core scales may be the result of gravitational collapse, with the field being pulled inward along with the flow of material under gravity.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144145897","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

Unveiling Two Deeply Embedded Young Protostars in the S68N Class 0 Protostellar Core with JWST/NIRSpec 用JWST/NIRSpec揭示S68N 0类原恒星核心中两颗深嵌的年轻原恒星

The Astrophysical Journal Pub Date : 2025-05-26 DOI: 10.3847/1538-4357/adcac4

Valentin J. M. Le Gouellec, Ben W. P. Lew, Thomas P. Greene, Doug Johnstone, Antoine Gusdorf, Logan Francis, Curtis DeWitt, Michael Meyer, Łukasz Tychoniec, Ewine F. van Dishoeck, Mary Barsony, Klaus W. Hodapp, Peter G. Martin and Massimo Robberto

{"title":"Unveiling Two Deeply Embedded Young Protostars in the S68N Class 0 Protostellar Core with JWST/NIRSpec","authors":"Valentin J. M. Le Gouellec, Ben W. P. Lew, Thomas P. Greene, Doug Johnstone, Antoine Gusdorf, Logan Francis, Curtis DeWitt, Michael Meyer, Łukasz Tychoniec, Ewine F. van Dishoeck, Mary Barsony, Klaus W. Hodapp, Peter G. Martin and Massimo Robberto","doi":"10.3847/1538-4357/adcac4","DOIUrl":"https://doi.org/10.3847/1538-4357/adcac4","url":null,"abstract":"The near-infrared (NIR) emission of the youngest protostars still needs to be characterized to better understand the evolution of their accretion and ejection activity. We analyze James Webb Space Telescope NIRSpec 1.7–5.3 μm observations of two deeply embedded sources in the S68N protostellar core in Serpens. The North Central source exhibits a highly obscured spectrum (AK ∼ 4.8 mag) that is modeled with a pre-main-sequence photosphere and a hot disk component. The photospheric parameters are consistent with a young, low-mass photosphere, as suggested by the low surface gravity, log g of 1.95 ±0.15 cm s−2. The hot disk suggests that accretion onto the central protostellar embryo is ongoing, although prototypical accretion-tracing emission lines H i are not detected. The South Central source, which is even more embedded (AK ∼ 8 mag; no continuum is detected shortward of 3.6 μm) appears to be driving the large-scale S68N protostellar outflow, and launches a collimated hot molecular jet detected in H2 and CO rovibrational lines. Shock modeling of the H2 (ro)vibrational lines establishes that fast C-type shocks (≥30 km s−1), with high pre-shock density (≥107 cm−3), and strong magnetic field (b ∼ 3–10, where ) best match the data. The bright CO fundamental line forest suggests energetic excitation, with the contribution of non-LTE effects, i.e., irradiation pumping. Detected OH and CH+ rovibrational lines support this hypothesis. These two Class 0 protostars seem to be in very young evolutionary stages and still have to acquire the bulk of their final stellar masses. These results demonstrate that JWST enables unprecedented diagnostics of these first stages of the protostellar evolutionary phase.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144153552","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

A Holistic Exploration of the Potentially Recoverable Redshift Information of Stage IV Galaxy Surveys 第四阶段星系巡天中潜在可恢复红移信息的整体探索

The Astrophysical Journal Pub Date : 2025-05-26 DOI: 10.3847/1538-4357/adc995

Bryan R. Scott, Alex I. Malz and Robert Sorba

{"title":"A Holistic Exploration of the Potentially Recoverable Redshift Information of Stage IV Galaxy Surveys","authors":"Bryan R. Scott, Alex I. Malz and Robert Sorba","doi":"10.3847/1538-4357/adc995","DOIUrl":"https://doi.org/10.3847/1538-4357/adc995","url":null,"abstract":"Extragalactic science and cosmology with Stage IV galaxy surveys will rely almost exclusively on redshift measurements derived solely from photometry, which are subject to systematic and statistical uncertainties with numerous analysis choices. Single-survey photometric redshift estimates ought to be improved by combining data from multiple surveys, with common wisdom asserting that optical data benefits from additional infrared (IR) but not ultraviolet (UV) coverage. The degree of improvement for either is not well characterized, and attempts necessitate assumptions of a chosen estimator and its prior information. We apply an information-theoretic metric of potentially recoverable redshift information to assess the impact of multi-survey photometry without assuming an estimator or priors in the context of the Vera C. Rubin Observatory Legacy Survey of Space and Time (lsst) in the optical, Roman and Euclid (roman and euclid) in the IR, and Cosmological Advanced Survey Telescope for Optical-UV Research (castor) in the UV. Our approach uses mock catalogs to approximate conditional relationships between color and redshift from real samples, but is otherwise independent of estimator and prior information. We conclude that adding UV photometry can benefit redshift determination of certain galaxy populations, but that gain is tempered by their decreased chance of meeting detection criteria at higher wavelengths. We explore the spectral energy distributions of galaxies whose potentially recoverable redshift information is most impacted by additional photometry. The holistic assessment approach we develop here is generic and may be applied to quantify the impact of combining photometric data sets, changing experimental design, optimizing observing strategy, and mitigating systematics.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144153590","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

Simulations of Coronal Mass Ejections on a Young Solar-type Star and Their Detectability Through Coronal Spectral Observations 一颗年轻太阳型恒星的日冕物质抛射模拟及其日冕光谱观测的可探测性

The Astrophysical Journal Pub Date : 2025-05-26 DOI: 10.3847/1538-4357/adcee7

Yu Xu, Hui Tian, Julián D. Alvarado-Gómez, Jeremy J. Drake and Gustavo Guerrero

{"title":"Simulations of Coronal Mass Ejections on a Young Solar-type Star and Their Detectability Through Coronal Spectral Observations","authors":"Yu Xu, Hui Tian, Julián D. Alvarado-Gómez, Jeremy J. Drake and Gustavo Guerrero","doi":"10.3847/1538-4357/adcee7","DOIUrl":"https://doi.org/10.3847/1538-4357/adcee7","url":null,"abstract":"There is a growing interest in searching for coronal mass ejections (CMEs) in other stellar systems, because they are thought to be one of the important factors shaping planetary atmospheres. We investigated the possible spectral signatures related to stellar CMEs using magnetohydrodynamic (MHD) simulations and spectral synthesis techniques. Blue-wing enhancements of the synthetic coronal line profiles caused by the line-of-sight motion of plasma were observed during the simulated CME events. We included instrumental conditions in the spectral synthesis and tested the detectability of the asymmetries under different instrumental broadening conditions. The results show that blue-wing asymmetries are visible in some extreme-ultraviolet lines with spectral resolutions higher than around 2000, and the line-of-sight velocities of CMEs obtained from asymmetry analysis techniques are comparable to the CME velocities derived from three-dimensional model outputs. However, when the spectral resolution drops below 2000, the asymmetries in the blue wings become barely visible, but blueshifts in the line centroids with velocities around −100 to −200 km s−1 are observed. We suggest a method of using MHD simulations to synthesize line profiles and analyze their asymmetries that may help to guide future instrument design, in terms of detecting stellar CMEs through Doppler shifts or the asymmetries of coronal spectral lines.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144145785","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

Quantifying the Limits of TESS Stellar Rotation Measurements with the K2-TESS Overlap 用K2-TESS重叠量化TESS恒星旋转测量的极限

The Astrophysical Journal Pub Date : 2025-05-26 DOI: 10.3847/1538-4357/adcecc

Andrew W. Boyle, Andrew W. Mann and Jonathan Bush

{"title":"Quantifying the Limits of TESS Stellar Rotation Measurements with the K2-TESS Overlap","authors":"Andrew W. Boyle, Andrew W. Mann and Jonathan Bush","doi":"10.3847/1538-4357/adcecc","DOIUrl":"https://doi.org/10.3847/1538-4357/adcecc","url":null,"abstract":"The Transiting Exoplanet Survey Satellite (TESS) has provided stellar rotation periods across much of the sky through high-precision light curves, but the reliability and completeness of these measurements require careful evaluation. We assess the accuracy of TESS-derived rotation periods by leveraging a cross-matched sample of ∼23,000 stars observed by both TESS and the K2 mission, treating K2 periods as a benchmark. Using causal pixel models to extract light curves and a Lomb–Scargle (LS) periodogram to identify rotation signals, we quantify the empirical uncertainties, reliability, and completeness of TESS rotation period measurements. We find that uncertainties on TESS-derived rotation periods are typically below 3% for stars with periods <10 days. Rotation periods are generally reliable out to 10 days, with ≳80% of measurements matching the K2 benchmark. Completeness and reliability drop dramatically for periods beyond ≃12 days due to the 27 day sector limitation. Stricter cuts on TESS magnitude and LS power improve reliability; the highest LS power tested (>0.2) ensures >90% reliability below 10 days but removes over half of potential detections. Stitching consecutive-sector light curves reduces period uncertainties but does not improve overall reliability or completeness due to persistent systematics. Our findings and code provide a framework for interpreting TESS-derived rotation periods and inform the selection of quality cuts to optimize studies of stellar rotation, young associations, and gyrochronology.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"45 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144145783","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

Magnetic Accretion Flow Explains the Hysteresis Q-diagram Seen in Outbursts of Black Hole Low-mass X-Ray Binaries 磁吸积流解释了黑洞低质量x射线双星爆发的滞后q图

The Astrophysical Journal Pub Date : 2025-05-26 DOI: 10.3847/1538-4357/add5e8

Jiahui Huang, Hua Feng and Lian Tao

{"title":"Magnetic Accretion Flow Explains the Hysteresis Q-diagram Seen in Outbursts of Black Hole Low-mass X-Ray Binaries","authors":"Jiahui Huang, Hua Feng and Lian Tao","doi":"10.3847/1538-4357/add5e8","DOIUrl":"https://doi.org/10.3847/1538-4357/add5e8","url":null,"abstract":"Black hole low-mass X-ray binaries undergo quiescence-outburst cycles. During the outbursts, they typically go through a q-shaped pattern in the hardness-intensity diagram (HID), known as the hysteresis q-diagram, while the physical nature is still unknown. We argue that the hysteresis q-diagram can be well explained with a recently proposed magnetized accretion disk model. The model takes into account the saturated magnetic pressure and predicts that the standard Shakura–Sunyaev disk (SSD) has an inner truncation at relatively low accretion rates, filled with an optically thin, hot accretion flow that resembles the advection-dominated accretion flow (ADAF) inside. Given a perturbation of accretion rate, the variation of the truncation radius can be derived as a result of thermal equilibrium by comparing the heating and cooling rates. We show that the truncation radius displays a hysteresis effect in response to the variation of mass accretion rate. As a result, the spectral hardness due to competition of the soft SSD and hard ADAF components is also hysteresis along with the rise and decay of the mass accretion rate or source intensity, leading to a q-shaped diagram in the HID.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144145788","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