{"title":"木星质量双星和宇宙射线粘度","authors":"J. I. Katz","doi":"10.1007/s10509-024-04339-x","DOIUrl":null,"url":null,"abstract":"<div><p>The fraction of planetary mass objects in the Trapezium cluster that are in wide binaries is much greater than implied by extrapolation to lower masses of the fraction of stars that are wide binaries. Wide binaries may be produced by gravitational collapse of a medium with fluid vorticity. In a uniform medium with uniform vorticity the collapse criterion is independent of the size and mass of the collapsing region, which would imply a wide binary fraction independent of mass, in contradiction to observation. Angular momentum, rather than thermal pressure, may be the chief obstacle to star formation. The excess of Jupiter Mass Binary Objects in the Trapezium cluster may be attributed to cosmic ray viscosity that transports angular momentum to surrounding material. Viscosity is more effective in smaller and less massive collapsing regions, preferentially producing planetary mass wide binaries.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"369 7","pages":""},"PeriodicalIF":1.8000,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Jupiter mass binaries and cosmic ray viscosity\",\"authors\":\"J. I. Katz\",\"doi\":\"10.1007/s10509-024-04339-x\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The fraction of planetary mass objects in the Trapezium cluster that are in wide binaries is much greater than implied by extrapolation to lower masses of the fraction of stars that are wide binaries. Wide binaries may be produced by gravitational collapse of a medium with fluid vorticity. In a uniform medium with uniform vorticity the collapse criterion is independent of the size and mass of the collapsing region, which would imply a wide binary fraction independent of mass, in contradiction to observation. Angular momentum, rather than thermal pressure, may be the chief obstacle to star formation. The excess of Jupiter Mass Binary Objects in the Trapezium cluster may be attributed to cosmic ray viscosity that transports angular momentum to surrounding material. Viscosity is more effective in smaller and less massive collapsing regions, preferentially producing planetary mass wide binaries.</p></div>\",\"PeriodicalId\":8644,\"journal\":{\"name\":\"Astrophysics and Space Science\",\"volume\":\"369 7\",\"pages\":\"\"},\"PeriodicalIF\":1.8000,\"publicationDate\":\"2024-07-30\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Astrophysics and Space Science\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s10509-024-04339-x\",\"RegionNum\":4,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"ASTRONOMY & ASTROPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Astrophysics and Space Science","FirstCategoryId":"101","ListUrlMain":"https://link.springer.com/article/10.1007/s10509-024-04339-x","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
The fraction of planetary mass objects in the Trapezium cluster that are in wide binaries is much greater than implied by extrapolation to lower masses of the fraction of stars that are wide binaries. Wide binaries may be produced by gravitational collapse of a medium with fluid vorticity. In a uniform medium with uniform vorticity the collapse criterion is independent of the size and mass of the collapsing region, which would imply a wide binary fraction independent of mass, in contradiction to observation. Angular momentum, rather than thermal pressure, may be the chief obstacle to star formation. The excess of Jupiter Mass Binary Objects in the Trapezium cluster may be attributed to cosmic ray viscosity that transports angular momentum to surrounding material. Viscosity is more effective in smaller and less massive collapsing regions, preferentially producing planetary mass wide binaries.
期刊介绍:
Astrophysics and Space Science publishes original contributions and invited reviews covering the entire range of astronomy, astrophysics, astrophysical cosmology, planetary and space science and the astrophysical aspects of astrobiology. This includes both observational and theoretical research, the techniques of astronomical instrumentation and data analysis and astronomical space instrumentation. We particularly welcome papers in the general fields of high-energy astrophysics, astrophysical and astrochemical studies of the interstellar medium including star formation, planetary astrophysics, the formation and evolution of galaxies and the evolution of large scale structure in the Universe. Papers in mathematical physics or in general relativity which do not establish clear astrophysical applications will no longer be considered.
The journal also publishes topically selected special issues in research fields of particular scientific interest. These consist of both invited reviews and original research papers. Conference proceedings will not be considered. All papers published in the journal are subject to thorough and strict peer-reviewing.
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