The Astrophysical Journal最新文献_第4页

Electron Acceleration at Shock Ripples: Role of Pitch-angle Diffusion 激波中的电子加速：俯仰角扩散的作用

The Astrophysical Journal Pub Date : 2025-07-14 DOI: 10.3847/1538-4357/ade23e

Y. D. Xu, G. Li and S. Yao

{"title":"Electron Acceleration at Shock Ripples: Role of Pitch-angle Diffusion","authors":"Y. D. Xu, G. Li and S. Yao","doi":"10.3847/1538-4357/ade23e","DOIUrl":"https://doi.org/10.3847/1538-4357/ade23e","url":null,"abstract":"Suprathermal electrons are routinely observed in interplanetary space. At higher energies, there are in-situ evidences that shocks, both interplanetary shocks, often driven by fast coronal mass ejections, and terrestrial bow shocks, can accelerate electrons up to transrelativistic energies (∼MeVs). The acceleration mechanism responsible for these energetic electrons is still under debate. In this work, we study the effects of large-scale shock ripples on electron acceleration at a quasi-perpendicular shock in a 2D system. For tractability of the numerical simulation, we consider the scenario where the magnetic field line contains ripples, and the shock is assumed planar and piecewise. The propagation of gyrophase-averaged electrons is governed by the focused transport equation, where the effect of the turbulent magnetic field is modeled by the pitch-angle diffusion, described by the quasi-linear theory. A Monte Carlo simulation on the equivalent time-forward Itô stochastic differential equation is performed within a periodic box to obtain the phase-space distribution function of the accelerated electrons. Our model predicts power-law energy spectra with a cutoff at high-energy ends, whereas their spectral indices are softer than those predicted by the diffusive shock acceleration theory. We demonstrate that, with a suitable choice of pitch-angle diffusion strength, a small fraction of electrons can experience magnetic traps in multiple ripples along the shock surface, boosting their energies to ∼MeVs. Our results therefore provide a framework for a better understanding of relativistic electron events associated with shocks within the heliosphere.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"670 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630339","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

Statistical Study on the Solar Wind Turbulence Spectra Upstream of Mars 火星上游太阳风湍流谱的统计研究

The Astrophysical Journal Pub Date : 2025-07-14 DOI: 10.3847/1538-4357/ade30c

Zhuxuan Zou, Yuming Wang, Zhenpeng Su, Long Cheng, Zhiyong Wu, Tielong Zhang, Guoqiang Wang, Sudong Xiao, Yutian Chi, Zonghao Pan, Xinjun Hao, Yiren Li and Kai Liu

{"title":"Statistical Study on the Solar Wind Turbulence Spectra Upstream of Mars","authors":"Zhuxuan Zou, Yuming Wang, Zhenpeng Su, Long Cheng, Zhiyong Wu, Tielong Zhang, Guoqiang Wang, Sudong Xiao, Yutian Chi, Zonghao Pan, Xinjun Hao, Yiren Li and Kai Liu","doi":"10.3847/1538-4357/ade30c","DOIUrl":"https://doi.org/10.3847/1538-4357/ade30c","url":null,"abstract":"We statistically analyze the power spectral density (PSD) of magnetic field turbulence in the upstream solar wind of the Martian bow shock by investigating the data from Tianwen-1 and Mars Atmosphere and Volatile Evolution (MAVEN) during 2021 November 13 and December 31. The spectral indices and break frequencies of these PSDs are automatically identified. According to the profiles of the PSDs, we find that they could be classified into three types: A, B, and C. Only less than a quarter of the events exhibit characteristics similar to the 1 au PSDs (Type A). We observe the energy injection in more than one-third of the events (Type B), and the injected energy usually results in the steeper spectral indices of the dissipation ranges. We find the absence of the dissipation range in over one third of the PSDs (Type C), which is likely due to the dissipation occurring at higher frequencies rather than proton cyclotron resonant frequencies. We also find that the two spacecraft observed different types of PSDs in more than half of the investigated episodes, indicating significant variability upstream of the Martian bow shock. For example, the Type-B PSDs are more often seen by Tianwen-1, which was near the flank of the bow shock, than by MAVEN near the nose. This statistical study demonstrates the complicated turbulent environment of the solar wind upstream of the Martian bow shock.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630342","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

Orbital Decay of the Ultra-hot Jupiter TOI-2109b: Tidal Constraints and Transit-timing Analysis 超热木星TOI-2109b的轨道衰减：潮汐约束和凌日时分析

The Astrophysical Journal Pub Date : 2025-07-14 DOI: 10.3847/1538-4357/ade057

Jaime A. Alvarado-Montes, Mario Sucerquia, Jorge I. Zuluaga and Christian Schwab

{"title":"Orbital Decay of the Ultra-hot Jupiter TOI-2109b: Tidal Constraints and Transit-timing Analysis","authors":"Jaime A. Alvarado-Montes, Mario Sucerquia, Jorge I. Zuluaga and Christian Schwab","doi":"10.3847/1538-4357/ade057","DOIUrl":"https://doi.org/10.3847/1538-4357/ade057","url":null,"abstract":"TOI-2109b is the ultra-hot Jupiter with the shortest orbital period (∼16 hr) yet discovered. At this close distance, strong tidal interactions can produce a significant exchange of angular momentum with the star. Since the orbital period of this planet is shorter than the stellar rotation period, TOI-2109b may be an optimal candidate for studying orbital decay. This process depends on how efficiently the star and the planet dissipate energy, due mainly to interior mechanisms that are poorly constrained in exoplanet systems. In this work, we study for the first time the tidal evolution of TOI-2109b under a formalism of inertial waves (IWs) in convective envelopes and internal gravity waves (IGWs) in stellar radiative regions. We find that uncertainties in the age of TOI-2109 (t⋆,age) significantly affect the rate of orbital evolution, as IWs and IGWs interact differently depending on t⋆,age. For an “old” host star, we find that TOI-2109b would undergo fast orbital decay. Conversely, if TOI-2109b orbits a “young” host star, a rather slow decay rate for would suggest a constant-period orbit. Our calculated mid-transit times and transit-timing variations (TTVs) support a “young” host star with , suggesting a decay rate that could lead to mid-transit-time shifts ≲10 s over three years. Orbital decay and other TTV-inducing effects will be confirmed or ruled out with future higher-quality timing data. The results presented here aim at constraining the current modeling of tides and TTVs for TOI-2109b, helping us further understand light-curve changes associated with the long-term evolution of ultra-short-period planets.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"45 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630329","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

Monte Carlo Evaluations of Gamma-Ray and Radio Pulsar Populations 伽玛射线和射电脉冲星群的蒙特卡洛评估

The Astrophysical Journal Pub Date : 2025-07-14 DOI: 10.3847/1538-4357/ade13f

Shawaiz Tabassum and Duncan R. Lorimer

{"title":"Monte Carlo Evaluations of Gamma-Ray and Radio Pulsar Populations","authors":"Shawaiz Tabassum and Duncan R. Lorimer","doi":"10.3847/1538-4357/ade13f","DOIUrl":"https://doi.org/10.3847/1538-4357/ade13f","url":null,"abstract":"Based on well-grounded Galactic neutron star populations formed from radio pulsar population syntheses of canonical pulsars (CPs) and millisecond pulsars (MSPs), we use the latest Fermi Large Area Telescope catalog (4FGL-DR4) to investigate the implications of proposed γ-ray luminosity models. Using Monte Carlo techniques, we calculate the number of CPs and MSPs that would comprise the sample of pulsar-like unidentified sources (PLUIDs) in 4FGL-DR4. While radio beaming fractions were used to scale the sizes of the populations, when forming the mock 4FGL-DR4 samples we make the simplifying assumption that all γ-ray pulsars are beaming toward the Earth. We then explore the observable outcomes of seven different γ-ray luminosity models. Four of the models provide a good match to the observed number of PLUIDs, while three others significantly overpredict the number of PLUIDs. For these latter models, either the average beaming fraction of γ-ray pulsars is more like 25%–50%, or a revision in the luminosity scaling is required. Most of the radio-detectable MSPs that our models predict as part of the PLUIDs within 4FGL-DR4 are, unsurprisingly, fainter than the currently observed sample and at larger dispersion measures. For CPs, in spite of an excellent match to the observed radio population, none of the γ-ray models we investigated could replicate the observed sample of 150 γ-ray CPs. Further work is required to understand this discrepancy. For both MSPs and CPs, we provide encouraging forecasts for targeted radio searches of PLUIDs from 4FGL-DR4 to elucidate the issues raised in this study.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630333","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

Strong Photospheric Heating Indicated by Fe i 6173 Å Line Emission during White-light Solar Flares fei 6173 Å白光太阳耀斑期间的线发射所指示的强光球加热

The Astrophysical Journal Pub Date : 2025-07-14 DOI: 10.3847/1538-4357/addd1e

Samuel Granovsky, Alexander G. Kosovichev, Viacheslav M. Sadykov, Graham S. Kerr and Joel C. Allred

{"title":"Strong Photospheric Heating Indicated by Fe i 6173 Å Line Emission during White-light Solar Flares","authors":"Samuel Granovsky, Alexander G. Kosovichev, Viacheslav M. Sadykov, Graham S. Kerr and Joel C. Allred","doi":"10.3847/1538-4357/addd1e","DOIUrl":"https://doi.org/10.3847/1538-4357/addd1e","url":null,"abstract":"Between 2017 and 2024, the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory has observed numerous white-light solar flares (WLFs). HMI spectropolarimetric observations of certain WLFs, in particular the X9.3 flare of 2017 September 6, reveal one or more locations within the umbra or along the umbra/penumbra boundary of the flaring active region where the Fe I 6173 Å line briefly goes into full emission, indicating significant heating of the photosphere and lower chromosphere. For five flares featuring Fe I 6173 Å line-core emission, we perform spectropolarimetric analysis using HMI 90 s cadence Stokes data. For all investigated flares, line-core emission is observed to last for a single 90 s frame and is either concurrent with or followed by an increase in the line continuum intensity lasting one to two frames (90–180 s). Additionally, permanent changes to the Stokes Q, U, and/or V profiles were observed, indicating long-lasting nontransient changes to the photospheric magnetic field. These emissions coincided with local maxima in hard X-ray emission observed by Konus-Wind, as well as local maxima in the time derivative of soft X-ray emission observed by GOES 16-18. Comparison of the Fe I 6173 Å line profile synthesis for the ad hoc heating of the initial empirical VAL-S umbra model and quiescent-Sun (VAL-C-like) model indicates that the Fe I 6173 Å line emission in the white-light flare kernels could be explained by the strong heating of initially cool photospheric regions.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"99 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630153","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

Where is the Supervirial Gas? The Supply from Hot Inflows 环境气体在哪里？热流入的供给

The Astrophysical Journal Pub Date : 2025-07-14 DOI: 10.3847/1538-4357/ade059

Manami Roy, Kung-Yi Su, Smita Mathur and Jonathan Stern

{"title":"Where is the Supervirial Gas? The Supply from Hot Inflows","authors":"Manami Roy, Kung-Yi Su, Smita Mathur and Jonathan Stern","doi":"10.3847/1538-4357/ade059","DOIUrl":"https://doi.org/10.3847/1538-4357/ade059","url":null,"abstract":"To understand the presence of the supervirial temperature gas detected in the Milky Way (MW), we present our findings from isolated galaxy simulations of MW-mass systems using GIZMO with the Feedback in Realistic Environments (FIRE-2) stellar feedback model. It unveils the presence of a significant supervirial temperature (T > Tvir) gas component within 20 kpc from the galactic center. We also find that 70%–90% of the total supervirial gas is extraplanar, at 1 < z < 6 kpc and Rcyl < 15 kpc. This supervirial gas has a mass of 1−2 × 107M⊙ with typical gas densities are 10−3.5−10−2.5 cm−3. We find that some of the virial gas (T ∼ 106 K) forms a rotating hot inflow, where gravitational energy is converted to thermal energy mainly via compressive heating. This process causes gas falling close to the rotation axis to reach supervirial temperatures via a combination of compressive heating and shocks just before cooling and joining the disk. Stellar feedback heating accounts for less than 1% of the supervirial gas, indicating its minimal influence despite expectations. Even in scenarios with no stellar feedback effects considered, abundant supervirial gas persists, highlighting the dominance of alternative heating mechanisms. We also show that cosmic rays do not have a significant effect on heating the gas to a supervirial temperature. Our study illuminates the intricate dynamics of hot virial and supervirial gas surrounding MW-mass galaxies, emphasizing the prominent role of infall-driven compressive and shock-heating processes in shaping thermal evolution.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630331","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 Growth and Decay of Individual Sunspots and Pores 单个太阳黑子和毛孔的生长和衰减

The Astrophysical Journal Pub Date : 2025-07-14 DOI: 10.3847/1538-4357/ade790

Andrei G. Tlatov

引用次数: 0

A Catalog of Galactic Supernova Remnants and Supernova Remnant Candidates from the EMU/POSSUM Radio Sky Surveys. I. 来自EMU/POSSUM射电巡天的银河系超新星遗迹和候选超新星遗迹目录。我。

The Astrophysical Journal Pub Date : 2025-07-14 DOI: 10.3847/1538-4357/addc63

B. D. Ball, R. Kothes, E. Rosolowsky, C. Burger-Scheidlin, M. D. Filipović, S. Lazarević, Z. J. Smeaton, W. Becker, E. Carretti, B. M. Gaensler, A. M. Hopkins, D. Leahy, M. Tahani, J. L. West, C. S. Anderson, S. Loru, Y. K. Ma, N. M. McClure-Griffiths and M. J. Michałowski

{"title":"A Catalog of Galactic Supernova Remnants and Supernova Remnant Candidates from the EMU/POSSUM Radio Sky Surveys. I.","authors":"B. D. Ball, R. Kothes, E. Rosolowsky, C. Burger-Scheidlin, M. D. Filipović, S. Lazarević, Z. J. Smeaton, W. Becker, E. Carretti, B. M. Gaensler, A. M. Hopkins, D. Leahy, M. Tahani, J. L. West, C. S. Anderson, S. Loru, Y. K. Ma, N. M. McClure-Griffiths and M. J. Michałowski","doi":"10.3847/1538-4357/addc63","DOIUrl":"https://doi.org/10.3847/1538-4357/addc63","url":null,"abstract":"We use data from the Evolutionary Map of the Universe (EMU) and Polarization Sky Survey of the Universe’s Magnetism (POSSUM) radio southern sky surveys, conducted with the Australian Square Kilometre Array Pathfinder (ASKAP) to compile a catalog of Galactic supernova remnants (SNRs) and candidate SNRs within the region of 277 5 ≤ ℓ ≤ 311 7 Galactic longitude, ∣b∣ ≤ 5 4 Galactic latitude, as well as an additional field along the Galactic plane, approximately 315 5 ≤ ℓ ≤ 323 0 Galactic longitude, −4.5 ≤ b ≤ 1.5 Galactic latitude. In the areas studied, there are 44 known SNRs and 46 SNR candidates that have been previously identified in the radio. We confirm eight of these candidates as SNRs based on evidence of linear polarization or through the calculation of nonthermal spectral indices. Additionally, we identify possible radio counterparts for seven SNR candidates that were previously only identified in X-rays (four) or optical (three). We also present six new SNRs and 37 new SNR candidates. The results of this study demonstrate the utility of ASKAP for discovering new and potential SNRs and refining the classification of previously identified candidates. In particular, we find that the EMU and POSSUM surveys are particularly well suited for observing high-latitude SNRs and confirming SNR candidates with polarization. The region studied in this work represents approximately one-quarter of the Galactic plane, by longitude, that will eventually be surveyed by EMU/POSSUM, and we expect that the ongoing surveys will continue to uncover new SNRs and SNR candidates.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144629953","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

Fundamental Parameters for Totally Eclipsing Contact Binaries Observed by TESS TESS观测到的全食接触双星基本参数

The Astrophysical Journal Pub Date : 2025-07-14 DOI: 10.3847/1538-4357/addfcf

Xu Ding, KaiFan Ji, ZhiMing Song, XueFen Tian, JinLiang Wang, ChuanJun Wang, QiYuan Cheng and JianPing Xiong

{"title":"Fundamental Parameters for Totally Eclipsing Contact Binaries Observed by TESS","authors":"Xu Ding, KaiFan Ji, ZhiMing Song, XueFen Tian, JinLiang Wang, ChuanJun Wang, QiYuan Cheng and JianPing Xiong","doi":"10.3847/1538-4357/addfcf","DOIUrl":"https://doi.org/10.3847/1538-4357/addfcf","url":null,"abstract":"Totally eclipsing contact binaries provide a unique opportunity to accurately determine mass ratios through photometric methods alone, eliminating the need for spectroscopic data. Studying low mass ratio (LMR) contact binaries is crucial for advancing our understanding of binary star evolution and the formation of rare optical transients known as red novae. We identified 143 totally eclipsing contact binaries from the Transiting Exoplanet Survey Satellite. These high-precision light curves reveal a distinct O’Connell effect, which we interpret by introducing a cool spot on the primary star. Training a neural network model that includes cool spot parameters can generate a high-precision light curve 2 orders of magnitude faster than Phoebe. Utilizing the neural network (NNnol3) model combined with the Markov Chain Monte Carlo algorithm, we rapidly derived the fundamental parameters of these systems. By leveraging the relationship between orbital period and semimajor axis using the Random Sample Consensus algorithm, we estimated their absolute parameters. Our analysis identified 96 targets with mass ratios below 0.25, all of which were not listed in any previous catalog, thus signifying the discovery of new LMR system candidates. Assuming all 143 binary systems are affected by a third light during parameter estimation, we train a neural network (NNl3) model considering the third light. Then we calculate the residuals between the mass ratio ql3 (considering the third light) and qnol3 (neglecting it). For these residuals, the 25th percentile (Q1) is 0.012, the median (Q2) is 0.026, and the 75th percentile (Q3) is 0.05.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630155","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

Prestellar Cores in Turbulent Clouds: Properties of Critical Cores 湍流云中的恒星前核：临界核的性质

The Astrophysical Journal Pub Date : 2025-07-14 DOI: 10.3847/1538-4357/ade239

Sanghyuk Moon and Eve C. Ostriker

{"title":"Prestellar Cores in Turbulent Clouds: Properties of Critical Cores","authors":"Sanghyuk Moon and Eve C. Ostriker","doi":"10.3847/1538-4357/ade239","DOIUrl":"https://doi.org/10.3847/1538-4357/ade239","url":null,"abstract":"A fraction of the dense cores within a turbulent molecular cloud will eventually collapse to form stars. Identifying the physical criteria for instability and analyzing critical core properties is therefore necessary to star formation theory. Here we quantify the characteristics of an ensemble of “critical cores” on the verge of collapse. This critical epoch was identified in a companion paper, which followed the dynamical evolution of prestellar cores in numerical simulations of turbulent, self-gravitating clouds. We find that radial profiles of density and turbulent velocity dispersion in individual critical cores are consistent with our new model for turbulent equilibrium spheres. While a global linewidth–size relation exists for a cloud with given size and Mach number, the turbulent scaling relations around each core exhibit significant variations. As a result, there is no single density threshold for collapse; instead, cores collapse at a range of densities determined by the local sonic scale and gravitational potential environment. The critical cores in our simulations are mostly transonic; we do not find either purely thermal or highly turbulent cores. In our low Mach number model, which better resolves the characteristic mass and sonic scales, we find marginal evidence that the core mass function (CMF) of critical cores peaks around a characteristic mass scale associated with the large-scale cloud properties. We highlight the importance of constructing the CMF at the critical time for the purpose of testing gravoturbulent fragmentation theories, and derive the resolution requirements to unambiguously identify the peak of the CMF.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144630336","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