Annual Review of Astronomy and Astrophysics最新文献_第2页

The Physical Origin of the Stellar Initial Mass Function 恒星初始质量函数的物理起源

IF 33.3 1区物理与天体物理

Annual Review of Astronomy and Astrophysics Pub Date : 2024-04-23 DOI: 10.1146/annurev-astro-052622-031748

P. Hennebelle, M.Y. Grudić

{"title":"The Physical Origin of the Stellar Initial Mass Function","authors":"P. Hennebelle, M.Y. Grudić","doi":"10.1146/annurev-astro-052622-031748","DOIUrl":"https://doi.org/10.1146/annurev-astro-052622-031748","url":null,"abstract":"Stars are among the most fundamental structures of our Universe. They comprise most of the baryonic and luminous mass of galaxies; synthesize heavy elements; and inject mass, momentum, and energy into the interstellar medium. They are also home to the planets. Because stellar properties are primarily decided by their mass, the so-called stellar initial mass function (IMF) is critical to the structuring of our Universe. We review the various physical processes and theories that have been put forward as well as the numerical simulations that have been carried out to explain the origin of the stellar IMF. Key messages from this review include the following: ▪ Gravity and turbulence most likely determine the power-law, high-mass part of the IMF. ▪ Depending of the Mach number and the density distribution, several regimes are possible, including ΓIMF ≃ 0, −0.8, −1, or −1.3, where dN/d log M ∝ M ΓIMF . These regimes are likely universal; however, the transition between these regimes is not. ▪ Protostellar jets can play a regulating influence on the IMF by injecting momentum into collapsing clumps and unbinding gas. ▪ The peak of the IMF may be a consequence of dust opacity and molecular hydrogen physics at the origin of the first hydrostatic core. This depends weakly on large-scale environmental conditions such as radiation, magnetic field, turbulence, or metallicity. This likely constitutes one reason for the relative universality of the IMF. ","PeriodicalId":8138,"journal":{"name":"Annual Review of Astronomy and Astrophysics","volume":"26 1","pages":""},"PeriodicalIF":33.3,"publicationDate":"2024-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140640384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dust Growth and Evolution in Protoplanetary Disks 原行星盘中的尘埃生长与演化

IF 33.3 1区物理与天体物理

Annual Review of Astronomy and Astrophysics Pub Date : 2024-04-19 DOI: 10.1146/annurev-astro-071221-052705

Tilman Birnstiel

{"title":"Dust Growth and Evolution in Protoplanetary Disks","authors":"Tilman Birnstiel","doi":"10.1146/annurev-astro-071221-052705","DOIUrl":"https://doi.org/10.1146/annurev-astro-071221-052705","url":null,"abstract":"Over the past decade, advancement of observational capabilities, specifically the Atacama Large Millimeter/submillimeter Array (ALMA) and Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) instruments, alongside theoretical innovations like pebble accretion, have reshaped our understanding of planet formation and the physics of protoplanetary disks. Despite this progress, mysteries persist along the winded path of micrometer-sized dust, from the interstellar medium, through transport and growth in the protoplanetary disk, to becoming gravitationally bound bodies. This review outlines our current knowledge of dust evolution in circumstellar disks, yielding the following insights: ▪ Theoretical and laboratory studies have accurately predicted the growth of dust particles to sizes that are susceptible to accumulation through transport processes like radial drift and settling. ▪ Critical uncertainties in that process remain the level of turbulence, the threshold collision velocities at which dust growth stalls, and the evolution of dust porosity. ▪ Symmetric and asymmetric substructure are widespread. Dust traps appear to be solving several long-standing issues in planet formation models, and they are observationally consistent with being sites of active planetesimal formation. ▪ In some instances, planets have been identified as the causes behind substructures. This underlines the need to study earlier stages of disks to understand how planets can form so rapidly. In the future, better probes of the physical conditions in optically thick regions, including densities, turbulence strength, kinematics, and particle properties will be essential for unraveling the physical processes at play.","PeriodicalId":8138,"journal":{"name":"Annual Review of Astronomy and Astrophysics","volume":"2 1","pages":""},"PeriodicalIF":33.3,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140621520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Interstellar Medium in Dwarf Irregular Galaxies 矮不规则星系中的星际介质

IF 33.3 1区物理与天体物理

Annual Review of Astronomy and Astrophysics Pub Date : 2024-04-19 DOI: 10.1146/annurev-astro-052722-104109

Deidre A. Hunter, Bruce G. Elmegreen, Suzanne C. Madden

{"title":"The Interstellar Medium in Dwarf Irregular Galaxies","authors":"Deidre A. Hunter, Bruce G. Elmegreen, Suzanne C. Madden","doi":"10.1146/annurev-astro-052722-104109","DOIUrl":"https://doi.org/10.1146/annurev-astro-052722-104109","url":null,"abstract":"Dwarf irregular (dIrrs) galaxies are among the most common type of galaxy in the Universe. They typically have gas-rich, low surface-brightness, metal-poor, and relatively thick disks. Here, we summarize the current state of our knowledge of the interstellar medium (ISM), including atomic, molecular, and ionized gas, along with their dust properties and metals. We also discuss star-formation feedback, gas accretion, and mergers with other dwarfs that connect the ISM to the circumgalactic and intergalactic media. We highlight one of the most persistent mysteries: the nature of pervasive gas that is yet undetected as either molecular or cold hydrogen, the “dark gas.” Some highlights include the following: ▪ Significant quantities of Hi are in far-outer gas disks. ▪ Cold Hi in dIrrs would be molecular in the Milky Way, making the chemical properties of star-forming clouds significantly different. ▪ Stellar feedback has a much larger impact in dIrrs than in spiral galaxies. ▪ The escape fraction of ionizing photons is significant, making dIrrs a plausible source for reionization in the early Universe. ▪ Observations suggest a significantly higher abundance of hydrogen (H2 or cold Hi) associated with CO in star-forming regions than that traced by the CO alone. ","PeriodicalId":8138,"journal":{"name":"Annual Review of Astronomy and Astrophysics","volume":"20 1","pages":""},"PeriodicalIF":33.3,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140621600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Plurality of Worlds 多元世界

IF 33.3 1区物理与天体物理

Annual Review of Astronomy and Astrophysics Pub Date : 2024-04-19 DOI: 10.1146/annurev-astro-071422-101131

Michel Mayor

引用次数: 0

The Evolution of Massive Binary Stars 大质量双星的演变

IF 33.3 1区物理与天体物理

Annual Review of Astronomy and Astrophysics Pub Date : 2024-04-19 DOI: 10.1146/annurev-astro-052722-105936

Pablo Marchant, Julia Bodensteiner

{"title":"The Evolution of Massive Binary Stars","authors":"Pablo Marchant, Julia Bodensteiner","doi":"10.1146/annurev-astro-052722-105936","DOIUrl":"https://doi.org/10.1146/annurev-astro-052722-105936","url":null,"abstract":"Massive stars play a major role in the evolution of their host galaxies and serve as important probes of the distant Universe. It has been established that the majority of massive stars reside in close binaries and interact with their companion stars during their lifetimes. Such interactions drastically alter their life cycles and complicate our understanding of their evolution, but are also responsible for the production of interesting and exotic interaction products. ▪ Extensive observation campaigns with well-understood detection sensitivities have enabled the conversion of observed properties into intrinsic characteristics, facilitating a direct comparison to theory. ▪ Studies of large samples of massive stars in our Galaxy and the Magellanic Clouds have unveiled new types of interaction products, providing critical constraints on the mass transfer phase and the formation of compact objects. ▪ The direct detection of gravitational waves has revolutionized the study of stellar mass compact objects, providing a new window to study massive star evolution. Their formation processes are, however, still unclear. The known sample of compact object mergers will increase by orders of magnitude in the coming decade, which is vastly outgrowing the number of stellar-mass compact objects detected through electromagnetic radiation. ","PeriodicalId":8138,"journal":{"name":"Annual Review of Astronomy and Astrophysics","volume":"4 1","pages":""},"PeriodicalIF":33.3,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140621588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Introduction 介绍

IF 33.3 1区物理与天体物理

Annual Review of Astronomy and Astrophysics Pub Date : 2023-08-18 DOI: 10.1146/annurev-aa-61-070323-100001

R. Kennicutt, E. V. van Dishoeck

引用次数: 0

Hydrodynamical Simulations of the Galaxy Population: Enduring Successes and Outstanding Challenges 银河系种群的流体动力学模拟：持久的成功和突出的挑战

IF 33.3 1区物理与天体物理

Annual Review of Astronomy and Astrophysics Pub Date : 2023-06-20 DOI: 10.1146/annurev-astro-041923-043618

R. Crain, F. Voort

{"title":"Hydrodynamical Simulations of the Galaxy Population: Enduring Successes and Outstanding Challenges","authors":"R. Crain, F. Voort","doi":"10.1146/annurev-astro-041923-043618","DOIUrl":"https://doi.org/10.1146/annurev-astro-041923-043618","url":null,"abstract":"We review the progress in modeling the galaxy population in hydrodynamical simulations of the ΛCDM cosmogony. State-of-the-art simulations now broadly reproduce the observed spatial clustering of galaxies; the distributions of key characteristics, such as mass, size, and SFR; and scaling relations connecting diverse properties to mass. Such improvements engender confidence in the insight drawn from simulations. Many important outcomes, however, particularly the properties of circumgalactic gas, are sensitive to the details of the subgrid models used to approximate the macroscopic effects of unresolved physics, such as feedback processes. We compare the outcomes of leading simulation suites with observations, and with each other, to identify the enduring successes they have cultivated and the outstanding challenges to be tackled with the next generation of models. Our key conclusions include the following: ▪ Realistic galaxies can be reproduced by calibrating the ill-constrained parameters of subgrid feedback models. Feedback is dominated by stars and black holes in low-mass and high mass galaxies, respectively. ▪ Adjusting or disabling the processes implemented in simulations can elucidate their impact on observables, but outcomes can be degenerate. ▪ Similar galaxy populations can emerge in simulations with dissimilar feedback implementations. However, these models generally predict markedly different gas flow rates into, and out of, galaxies and their halos. CGM observations are thus a promising means of breaking this degeneracy and guiding the development of new feedback models. Expected final online publication date for the Annual Review of Astronomy and Astrophysics, Volume 61 is August 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.","PeriodicalId":8138,"journal":{"name":"Annual Review of Astronomy and Astrophysics","volume":" ","pages":""},"PeriodicalIF":33.3,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47355078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

New Insights from Imaging Spectroscopy of Solar Radio Emission 太阳射电发射成像光谱学的新见解

IF 33.3 1区物理与天体物理

Annual Review of Astronomy and Astrophysics Pub Date : 2023-06-12 DOI: 10.1146/annurev-astro-071221-052744

D. Gary

{"title":"New Insights from Imaging Spectroscopy of Solar Radio Emission","authors":"D. Gary","doi":"10.1146/annurev-astro-071221-052744","DOIUrl":"https://doi.org/10.1146/annurev-astro-071221-052744","url":null,"abstract":"Newly available high-resolution imaging of solar radio emission at many closely spaced frequencies and times provides new physical insight into the processes, structure, and dynamics of the solar atmosphere. The observational advances have spurred renewed interest in topics dating from the early days of solar radio astronomy and have led to considerable advances in our knowledge. Highlights of recent advances include the following: ▪ Quantitatively measuring the dynamic magnetic field strength, particle acceleration, and hot thermal plasma at the heart of solar flares and hinting at the processes that relate them. ▪ Resolving in space and time the energization and transport of electrons in a wide range of contexts. ▪ Mapping the magnetized thermal plasma structure of the solar chromosphere and corona over a substantial range of heights in active and quiet regions of the Sun. This review explains why solar radio imaging spectroscopy is so powerful, describes the body of recent results, and outlines the future work needed to fully realize its potential. The application of radio imaging spectroscopy to stars and planets is also briefly reviewed. Expected final online publication date for the Annual Review of Astronomy and Astrophysics, Volume 61 is August 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.","PeriodicalId":8138,"journal":{"name":"Annual Review of Astronomy and Astrophysics","volume":" ","pages":""},"PeriodicalIF":33.3,"publicationDate":"2023-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48801813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Protoplanetary Disk Chemistry 原行星盘化学

IF 33.3 1区物理与天体物理

Annual Review of Astronomy and Astrophysics Pub Date : 2023-06-07 DOI: 10.1146/annurev-astro-022823-040820

K. Oberg, S. Facchini, D. Anderson

{"title":"Protoplanetary Disk Chemistry","authors":"K. Oberg, S. Facchini, D. Anderson","doi":"10.1146/annurev-astro-022823-040820","DOIUrl":"https://doi.org/10.1146/annurev-astro-022823-040820","url":null,"abstract":"Planets form in disks of gas and dust around young stars. The disk molecular reservoirs and their chemical evolution affect all aspects of planet formation, from the coagulation of dust grains into pebbles to the elemental and molecular compositions of the mature planet. Disk chemistry also enables unique probes of disk structures and dynamics, including those directly linked to ongoing planet formation. We review the protoplanetary disk chemistry of the volatile elements H, O, C, N, S, and P; the associated observational and theoretical methods; and the links between disk and planet chemical compositions. Three takeaways from this review are: ▪ The disk chemical composition, including the organic reservoirs, is set by both inheritance and in situ chemistry. ▪ Disk gas and solid O/C/N/H elemental ratios often deviate from stellar values due to a combination of condensation of molecular carriers, chemistry, and dynamics. ▪ Chemical, physical, and dynamical processes in disks are closely linked, which complicates disk chemistry modeling, but they also present an opportunity to develop chemical probes of different aspects of disk evolution and planet formation. Expected final online publication date for the Annual Review of Astronomy and Astrophysics, Volume 61 is August 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.","PeriodicalId":8138,"journal":{"name":"Annual Review of Astronomy and Astrophysics","volume":" ","pages":""},"PeriodicalIF":33.3,"publicationDate":"2023-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44169727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Atomic Hydrogen in the Milky Way: A Stepping Stone in the Evolution of Galaxies 银河系中的氢原子:星系演化的垫脚石

IF 33.3 1区物理与天体物理

Annual Review of Astronomy and Astrophysics Pub Date : 2023-05-30 DOI: 10.1146/annurev-astro-052920-104851

N. McClure-Griffiths, S. Stanimirović, D. Rybarczyk

{"title":"Atomic Hydrogen in the Milky Way: A Stepping Stone in the Evolution of Galaxies","authors":"N. McClure-Griffiths, S. Stanimirović, D. Rybarczyk","doi":"10.1146/annurev-astro-052920-104851","DOIUrl":"https://doi.org/10.1146/annurev-astro-052920-104851","url":null,"abstract":"Atomic hydrogen (Hi) is a critical stepping stone in the gas evolution cycle of the interstellar medium (ISM) of the Milky Way. Hi traces both the cold, premolecular state before star formation and the warm, diffuse ISM before and after star formation. This review describes new, sensitive Hi absorption and emission surveys, which, together with high angular and spectral resolution Hi emission data, have revealed the physical properties of Hi, its structure, and its association with magnetic fields. We give an overview of the Hi phases and discuss how Hi properties depend on the environment and what its structure can tell us about feedback in the ISM. Key findings include the following: ▪ The mass fraction of the cold neutral medium is [Formula: see text]40% on average, increasing with AV due to the increase of mean gas density. ▪ The cold disk extends to at least R ∼ 25 kpc. ▪ Approximately 40% of the Hi is warm, with structural characteristics that derive from feedback events. ▪ Cold Hi is highly filamentary, whereas warm Hi is more smoothly distributed. We summarize future observational and simulation opportunities that can be used to unravel the 3D structure of the atomic ISM and the effects of heating and cooling on Hi properties. Expected final online publication date for the Annual Review of Astronomy and Astrophysics, Volume 61 is August 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.","PeriodicalId":8138,"journal":{"name":"Annual Review of Astronomy and Astrophysics","volume":" ","pages":""},"PeriodicalIF":33.3,"publicationDate":"2023-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47695938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3