Evaristus U. Iyida, Emmanuel Proven-Adzri, Diana Y. Klutse, Theophilus Ansah-Narh
{"title":"相对论光束对高亮度射电源统一模型的贡献","authors":"Evaristus U. Iyida, Emmanuel Proven-Adzri, Diana Y. Klutse, Theophilus Ansah-Narh","doi":"10.1007/s12036-025-10086-4","DOIUrl":null,"url":null,"abstract":"<div><p>In this study, we apply the dual-component model of <span>\\(\\gamma \\)</span>-ray emission to assess the validity of the unified scheme for high-luminosity radio sources, specifically, Fanaroff–Riley Type II radio galaxies (FR IIs) and Flat-Spectrum Radio Quasars (FSRQs). We analyse a combined dataset comprising 220 FSRQs detected by the <i>Fermi</i> Large Area Telescope (<i>Fermi</i>-LAT) and 107 non-<i>Fermi</i> detected FR IIs. Utilizing the concept of relativistic beaming, we compute both the extended and core <span>\\(\\gamma \\)</span>-ray emissions and used the <span>\\(\\gamma \\)</span>-ray beaming factor (<span>\\(g_\\gamma (\\beta , \\psi )\\)</span>) to estimate the <span>\\(\\gamma \\)</span>-ray core-dominance. Our main findings are as follows: (1) Radio (<span>\\(R_r\\)</span>) and <span>\\(\\gamma \\)</span>-ray (<span>\\(R_\\gamma \\)</span>) core-dominance parameters (in logarithmic scale) range from −2.40 to 4.32 and −1.63 to 9.73, respectively, for FSRQs, with mean values of 1.36 and 2.52. In contrast, for FR IIs, <span>\\(R_r\\)</span> and <span>\\(R_\\gamma \\)</span> span −3.30 to 0.27 and −1.82 to 3.79, with mean values of 0.16 and 0.23, respectively. The significantly lower core-dominance of FR IIs compared to FSRQs, supports the unified model, wherein FR IIs represent the misaligned counterparts of FSRQs. (2) <span>\\(\\gamma \\)</span>-ray emission in FSRQs is predominantly core-dominated, exceeding the contribution from the extended region by approximately three orders of magnitude. Strong anti-correlations between <span>\\(R_r\\)</span>, <span>\\(R_\\gamma \\)</span> and their respective emission components further indicate that <span>\\(\\gamma \\)</span>-ray production is substantially influenced by relativistic beaming effects. (3) Distribution of FR IIs in the parameter space of <span>\\(R_r\\)</span> and <span>\\(R_\\gamma \\)</span> vs. <span>\\(\\gamma \\)</span>-ray emission suggests the presence of varying beaming effects across different regions. These findings indicate that <span>\\(\\gamma \\)</span>-ray emission in FSRQs originates primarily from the core and reveals the contributions of relativistic beaming effect to the unified model of high luminosity samples of FSRQs and FR IIs.</p></div>","PeriodicalId":610,"journal":{"name":"Journal of Astrophysics and Astronomy","volume":"46 2","pages":""},"PeriodicalIF":1.6000,"publicationDate":"2025-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Contributions of relativistic beaming to the unified model of high-luminosity radio sources\",\"authors\":\"Evaristus U. Iyida, Emmanuel Proven-Adzri, Diana Y. Klutse, Theophilus Ansah-Narh\",\"doi\":\"10.1007/s12036-025-10086-4\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>In this study, we apply the dual-component model of <span>\\\\(\\\\gamma \\\\)</span>-ray emission to assess the validity of the unified scheme for high-luminosity radio sources, specifically, Fanaroff–Riley Type II radio galaxies (FR IIs) and Flat-Spectrum Radio Quasars (FSRQs). We analyse a combined dataset comprising 220 FSRQs detected by the <i>Fermi</i> Large Area Telescope (<i>Fermi</i>-LAT) and 107 non-<i>Fermi</i> detected FR IIs. Utilizing the concept of relativistic beaming, we compute both the extended and core <span>\\\\(\\\\gamma \\\\)</span>-ray emissions and used the <span>\\\\(\\\\gamma \\\\)</span>-ray beaming factor (<span>\\\\(g_\\\\gamma (\\\\beta , \\\\psi )\\\\)</span>) to estimate the <span>\\\\(\\\\gamma \\\\)</span>-ray core-dominance. Our main findings are as follows: (1) Radio (<span>\\\\(R_r\\\\)</span>) and <span>\\\\(\\\\gamma \\\\)</span>-ray (<span>\\\\(R_\\\\gamma \\\\)</span>) core-dominance parameters (in logarithmic scale) range from −2.40 to 4.32 and −1.63 to 9.73, respectively, for FSRQs, with mean values of 1.36 and 2.52. In contrast, for FR IIs, <span>\\\\(R_r\\\\)</span> and <span>\\\\(R_\\\\gamma \\\\)</span> span −3.30 to 0.27 and −1.82 to 3.79, with mean values of 0.16 and 0.23, respectively. The significantly lower core-dominance of FR IIs compared to FSRQs, supports the unified model, wherein FR IIs represent the misaligned counterparts of FSRQs. (2) <span>\\\\(\\\\gamma \\\\)</span>-ray emission in FSRQs is predominantly core-dominated, exceeding the contribution from the extended region by approximately three orders of magnitude. Strong anti-correlations between <span>\\\\(R_r\\\\)</span>, <span>\\\\(R_\\\\gamma \\\\)</span> and their respective emission components further indicate that <span>\\\\(\\\\gamma \\\\)</span>-ray production is substantially influenced by relativistic beaming effects. (3) Distribution of FR IIs in the parameter space of <span>\\\\(R_r\\\\)</span> and <span>\\\\(R_\\\\gamma \\\\)</span> vs. <span>\\\\(\\\\gamma \\\\)</span>-ray emission suggests the presence of varying beaming effects across different regions. These findings indicate that <span>\\\\(\\\\gamma \\\\)</span>-ray emission in FSRQs originates primarily from the core and reveals the contributions of relativistic beaming effect to the unified model of high luminosity samples of FSRQs and FR IIs.</p></div>\",\"PeriodicalId\":610,\"journal\":{\"name\":\"Journal of Astrophysics and Astronomy\",\"volume\":\"46 2\",\"pages\":\"\"},\"PeriodicalIF\":1.6000,\"publicationDate\":\"2025-08-09\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Astrophysics and Astronomy\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s12036-025-10086-4\",\"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":"Journal of Astrophysics and Astronomy","FirstCategoryId":"101","ListUrlMain":"https://link.springer.com/article/10.1007/s12036-025-10086-4","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}
Contributions of relativistic beaming to the unified model of high-luminosity radio sources
In this study, we apply the dual-component model of \(\gamma \)-ray emission to assess the validity of the unified scheme for high-luminosity radio sources, specifically, Fanaroff–Riley Type II radio galaxies (FR IIs) and Flat-Spectrum Radio Quasars (FSRQs). We analyse a combined dataset comprising 220 FSRQs detected by the Fermi Large Area Telescope (Fermi-LAT) and 107 non-Fermi detected FR IIs. Utilizing the concept of relativistic beaming, we compute both the extended and core \(\gamma \)-ray emissions and used the \(\gamma \)-ray beaming factor (\(g_\gamma (\beta , \psi )\)) to estimate the \(\gamma \)-ray core-dominance. Our main findings are as follows: (1) Radio (\(R_r\)) and \(\gamma \)-ray (\(R_\gamma \)) core-dominance parameters (in logarithmic scale) range from −2.40 to 4.32 and −1.63 to 9.73, respectively, for FSRQs, with mean values of 1.36 and 2.52. In contrast, for FR IIs, \(R_r\) and \(R_\gamma \) span −3.30 to 0.27 and −1.82 to 3.79, with mean values of 0.16 and 0.23, respectively. The significantly lower core-dominance of FR IIs compared to FSRQs, supports the unified model, wherein FR IIs represent the misaligned counterparts of FSRQs. (2) \(\gamma \)-ray emission in FSRQs is predominantly core-dominated, exceeding the contribution from the extended region by approximately three orders of magnitude. Strong anti-correlations between \(R_r\), \(R_\gamma \) and their respective emission components further indicate that \(\gamma \)-ray production is substantially influenced by relativistic beaming effects. (3) Distribution of FR IIs in the parameter space of \(R_r\) and \(R_\gamma \) vs. \(\gamma \)-ray emission suggests the presence of varying beaming effects across different regions. These findings indicate that \(\gamma \)-ray emission in FSRQs originates primarily from the core and reveals the contributions of relativistic beaming effect to the unified model of high luminosity samples of FSRQs and FR IIs.
期刊介绍:
The journal publishes original research papers on all aspects of astrophysics and astronomy, including instrumentation, laboratory astrophysics, and cosmology. Critical reviews of topical fields are also published.
Articles submitted as letters will be considered.