The Astronomy and Astrophysics Review最新文献_第3页

Low-energy cosmic rays: regulators of the dense interstellar medium 低能宇宙射线:密集星际介质的调节器

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2022-09-03 DOI: 10.1007/s00159-022-00141-2

Stefano Gabici

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引用次数: 7

Ram pressure stripping in high-density environments 高密度环境下闸板压力剥离

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2022-05-18 DOI: 10.1007/s00159-022-00140-3

Alessandro Boselli, Matteo Fossati, Ming Sun

{"title":"Ram pressure stripping in high-density environments","authors":"Alessandro Boselli, Matteo Fossati, Ming Sun","doi":"10.1007/s00159-022-00140-3","DOIUrl":"10.1007/s00159-022-00140-3","url":null,"abstract":"<div><p>Galaxies living in rich environments are suffering different perturbations able to drastically affect their evolution. Among these, ram pressure stripping, i.e. the pressure exerted by the hot and dense intracluster medium (ICM) on galaxies moving at high velocity within the cluster gravitational potential well, is a key process able to remove their interstellar medium (ISM) and quench their activity of star formation. This review is aimed at describing this physical mechanism in different environments, from rich clusters of galaxies to loose and compact groups. We summarise the effects of this perturbing process on the baryonic components of galaxies, from the different gas phases (cold atomic and molecular, ionised, hot) to magnetic fields and cosmic rays, and describe their induced effects on the different stellar populations, with a particular attention to its role in the quenching episode generally observed in high-density environments. We also discuss on the possible fate of the stripped material once removed from the perturbed galaxies and mixed with the ICM, and we try to estimate its contribution to the pollution of the surrounding environment. Finally, combining the results of local and high-redshift observations with the prediction of tuned models and simulations, we try to quantify the importance of this process on the evolution of galaxies of different mass, from dwarfs to giants, in various environments and at different epochs.</p></div>","PeriodicalId":785,"journal":{"name":"The Astronomy and Astrophysics Review","volume":"30 1","pages":""},"PeriodicalIF":25.8,"publicationDate":"2022-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00159-022-00140-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134796962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 33

Fast radio bursts at the dawn of the 2020s 本世纪20年代初的快速射电暴

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2022-03-29 DOI: 10.1007/s00159-022-00139-w

E. Petroff, J. W. T. Hessels, D. R. Lorimer

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引用次数: 69

The growing threat of light pollution to ground-based observatories 光污染对地面天文台的威胁日益严重

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2022-01-27 DOI: 10.1007/s00159-021-00138-3

Richard F. Green, Christian B. Luginbuhl, Richard J. Wainscoat, Dan Duriscoe

{"title":"The growing threat of light pollution to ground-based observatories","authors":"Richard F. Green, Christian B. Luginbuhl, Richard J. Wainscoat, Dan Duriscoe","doi":"10.1007/s00159-021-00138-3","DOIUrl":"10.1007/s00159-021-00138-3","url":null,"abstract":"<div><p>Human activity is rapidly increasing the negative impact of artificial skyglow at even the most remote professional observatory sites. Assessment of the actual impact requires an understanding of the propagation as a function of source spectral energy distribution. The higher blue content of light-emitting diodes being widely used as replacement for sodium discharge lamps has greater impact closer to the source, and less impact for more distant mountain-top sites. All-sky cameras with moderate angular resolution provide data and metrics sufficient to model and remove celestial contributions and provide measures of artificial light contribution. The natural skyglow is significantly affected by solar activity, which must be accounted for in determining secular trends in the artificial component. With the availability of the New World Atlas of the Artificial Sky Brightness, a direct comparison is made of the modeled artificial contribution to the sites with the largest aperture telescopes, noting the possible systematic errors in individual cases. Population growth of the nearest urban centers allows a prediction of the change in that brightness over a decade. All site protections are effected primarily by national or regional regulation. A collection of worldwide regulations shows that most are leveraged off environmental protection statutes, while in the U.S., they are largely based on land-use zones. Particular examples are presented in more detail for Flagstaff, Arizona, and the Island of Hawai’i. The latest rapidly growing threat is that of reflected sunlight from large constellations of satellites in low-earth orbit. A snapshot is provided of that rapidly changing situation. In all cases, astronomers must become very proactive in educating the public about the cultural value of visual or naked eye astronomy as well as the science and the need for access to a dark night sky for astronomical research.</p></div>","PeriodicalId":785,"journal":{"name":"The Astronomy and Astrophysics Review","volume":"30 1","pages":""},"PeriodicalIF":25.8,"publicationDate":"2022-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00159-021-00138-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5042255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 23

A Brief Review on the Research of Testing of Cosmological Principle 宇宙原理检验研究述评

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2022-01-01 DOI: 10.12677/aas.2022.104004

宇航唐

引用次数: 0

How Gravity Is Produced?—Lines of Gravitation Are Deflecting the Direction of Motion of an Object 重力是如何产生的?引力线使物体的运动方向发生偏转

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2022-01-01 DOI: 10.12677/aas.2022.102002

军利陈

引用次数: 1

Gravity, Gravitational Fields, and Gravitons—Inference about the Frequency of Gravitational Energy Waves 重力、引力场和引力子——关于引力波频率的推断

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2022-01-01 DOI: 10.12677/aas.2022.101001

军利陈

引用次数: 1

The Hubble Constant Tension in Cosmology 宇宙学中的哈勃恒张力

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2022-01-01 DOI: 10.12677/aas.2022.103003

术银杨

引用次数: 0

A buyer’s guide to the Hubble constant 哈勃常数的买家指南

IF 27.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-12-01 DOI: 10.1007/s00159-021-00137-4

Paul Shah, Pablo Lemos, Ofer Lahav

{"title":"A buyer’s guide to the Hubble constant","authors":"Paul Shah, Pablo Lemos, Ofer Lahav","doi":"10.1007/s00159-021-00137-4","DOIUrl":"10.1007/s00159-021-00137-4","url":null,"abstract":"<div><p>Since the expansion of the universe was first established by Edwin Hubble and Georges Lemaître about a century ago, the Hubble constant <span>(H_0)</span> which measures its rate has been of great interest to astronomers. Besides being interesting in its own right, few properties of the universe can be deduced without it. In the last decade, a significant gap has emerged between different methods of measuring it, some anchored in the nearby universe, others at cosmological distances. The SH0ES team has found <span>(H_0 = 73.2 pm 1.3 ; ;,hbox {kms}^{-1} ,hbox {Mpc}^{-1})</span> locally, whereas the value found for the early universe by the Planck Collaboration is <span>(H_0 = 67.4 pm 0.5 ; ;,hbox {kms}^{-1} ,hbox {Mpc}^{-1})</span> from measurements of the cosmic microwave background. Is this gap a sign that the well-established <span>({varLambda} {text{CDM}})</span> cosmological model is somehow incomplete? Or are there unknown systematics? And more practically, how should humble astronomers pick between competing claims if they need to assume a value for a certain purpose? In this article, we review results and what changes to the cosmological model could be needed to accommodate them all. For astronomers in a hurry, we provide a buyer’s guide to the results, and make recommendations.</p></div>","PeriodicalId":785,"journal":{"name":"The Astronomy and Astrophysics Review","volume":"29 1","pages":""},"PeriodicalIF":27.8,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00159-021-00137-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138514251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Rotation of an oblate satellite: Chaos control (Corrigendum) 一个扁圆卫星的旋转:混沌控制(勘误)

IF 25.8 1区物理与天体物理

The Astronomy and Astrophysics Review Pub Date : 2021-11-01 DOI: 10.1051/0004-6361/201731167E

M. Tarnopolski

引用次数: 0