{"title":"白矮星由净电荷产生的额外压力","authors":"Ting-Han Pei","doi":"10.1093/pasj/psad047","DOIUrl":null,"url":null,"abstract":"\n The upper-mass limit of a white dwarf star is predicted to be 1.44 ${M}_{\\odot} $ based on an ideally degenerate Fermi electron gas at a temperature of absolute zero. However, more conditions should be considered, such as temperature and charge. In this research, first, we use the grand partition function in statistical mechanics to build expressions for the electron gas pressure and the particle number depending on temperature. At 1.16 × 107 K, there is a total of about 1.50 × 10−4 electrons exceeding the Fermi energy, and about 1.50 × 10−7 at 1.16 × 104 K. Because some of these Fermi electrons are extremely relativistic, some of them can escape the gravity and some return to the star after leaving. These two mechanisms result in a positively charged star and the net positive charges produce a repulsive force and pressure against gravity. The increased pressure is comparable to that of the Fermi electron gas at T = 0 when the star is charged at 1020 C. The net charges will decrease the mass density of the star but increase the upper-mass limit.","PeriodicalId":20733,"journal":{"name":"Publications of the Astronomical Society of Japan","volume":null,"pages":null},"PeriodicalIF":2.2000,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"The additional pressure of white dwarf stars generated by net charges\",\"authors\":\"Ting-Han Pei\",\"doi\":\"10.1093/pasj/psad047\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"\\n The upper-mass limit of a white dwarf star is predicted to be 1.44 ${M}_{\\\\odot} $ based on an ideally degenerate Fermi electron gas at a temperature of absolute zero. However, more conditions should be considered, such as temperature and charge. In this research, first, we use the grand partition function in statistical mechanics to build expressions for the electron gas pressure and the particle number depending on temperature. At 1.16 × 107 K, there is a total of about 1.50 × 10−4 electrons exceeding the Fermi energy, and about 1.50 × 10−7 at 1.16 × 104 K. Because some of these Fermi electrons are extremely relativistic, some of them can escape the gravity and some return to the star after leaving. These two mechanisms result in a positively charged star and the net positive charges produce a repulsive force and pressure against gravity. The increased pressure is comparable to that of the Fermi electron gas at T = 0 when the star is charged at 1020 C. The net charges will decrease the mass density of the star but increase the upper-mass limit.\",\"PeriodicalId\":20733,\"journal\":{\"name\":\"Publications of the Astronomical Society of Japan\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":2.2000,\"publicationDate\":\"2023-08-09\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Publications of the Astronomical Society of Japan\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://doi.org/10.1093/pasj/psad047\",\"RegionNum\":4,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ASTRONOMY & ASTROPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Publications of the Astronomical Society of Japan","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1093/pasj/psad047","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
The additional pressure of white dwarf stars generated by net charges
The upper-mass limit of a white dwarf star is predicted to be 1.44 ${M}_{\odot} $ based on an ideally degenerate Fermi electron gas at a temperature of absolute zero. However, more conditions should be considered, such as temperature and charge. In this research, first, we use the grand partition function in statistical mechanics to build expressions for the electron gas pressure and the particle number depending on temperature. At 1.16 × 107 K, there is a total of about 1.50 × 10−4 electrons exceeding the Fermi energy, and about 1.50 × 10−7 at 1.16 × 104 K. Because some of these Fermi electrons are extremely relativistic, some of them can escape the gravity and some return to the star after leaving. These two mechanisms result in a positively charged star and the net positive charges produce a repulsive force and pressure against gravity. The increased pressure is comparable to that of the Fermi electron gas at T = 0 when the star is charged at 1020 C. The net charges will decrease the mass density of the star but increase the upper-mass limit.
期刊介绍:
Publications of the Astronomical Society of Japan (PASJ) publishes the results of original research in all aspects of astronomy, astrophysics, and fields closely related to them.