Zulema Abraham, Pedro P. B. Beaklini, Isabel Aleman, Raghvendra Sahai, Albert Zijlstra, Stavros Akras, Denise R. Gonçalves and Toshiya Ueta
{"title":"ALMA 在行星状星云 Mz3 的氢重组线中探测到 Masers 和 Dasars","authors":"Zulema Abraham, Pedro P. B. Beaklini, Isabel Aleman, Raghvendra Sahai, Albert Zijlstra, Stavros Akras, Denise R. Gonçalves and Toshiya Ueta","doi":"10.3847/1538-4357/ad77c6","DOIUrl":null,"url":null,"abstract":"The hydrogen recombination lines H30α, H40α, H42α, H50β, and H57γ and the underlying bremsstrahlung continuum emission were detected with ALMA in the bipolar nebula Mz3. The source was not spatially resolved, but the velocity profile of the H30α line shows clear indication of maser amplification, confirming previous reports of laser amplification in the far-infrared H recombination lines observed with Herschel Space Observatory. Comparison between the flux densities of the H50β, H40α, and H42α lines show overcooling, or darkness amplification by stimulated absorption (dasar effect) at the LSR velocity of about −25 km s−1, which constrains the density of the absorbing region to about 103 cm−3. The H30α line, on the other hand, presents maser lines at LSR velocities of −69 and −98 km s−1, which indicates ionized gas with densities close to 107 cm−3. Although the source of emission was not resolved, it was possible to find the central position of the images for each velocity interval, which resulted in a well defined position–velocity distribution.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"ALMA Detection of Masers and Dasars in the Hydrogen Recombination Lines of the Planetary Nebula Mz3\",\"authors\":\"Zulema Abraham, Pedro P. B. Beaklini, Isabel Aleman, Raghvendra Sahai, Albert Zijlstra, Stavros Akras, Denise R. Gonçalves and Toshiya Ueta\",\"doi\":\"10.3847/1538-4357/ad77c6\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The hydrogen recombination lines H30α, H40α, H42α, H50β, and H57γ and the underlying bremsstrahlung continuum emission were detected with ALMA in the bipolar nebula Mz3. The source was not spatially resolved, but the velocity profile of the H30α line shows clear indication of maser amplification, confirming previous reports of laser amplification in the far-infrared H recombination lines observed with Herschel Space Observatory. Comparison between the flux densities of the H50β, H40α, and H42α lines show overcooling, or darkness amplification by stimulated absorption (dasar effect) at the LSR velocity of about −25 km s−1, which constrains the density of the absorbing region to about 103 cm−3. The H30α line, on the other hand, presents maser lines at LSR velocities of −69 and −98 km s−1, which indicates ionized gas with densities close to 107 cm−3. Although the source of emission was not resolved, it was possible to find the central position of the images for each velocity interval, which resulted in a well defined position–velocity distribution.\",\"PeriodicalId\":501813,\"journal\":{\"name\":\"The Astrophysical Journal\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-10-15\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"The Astrophysical Journal\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.3847/1538-4357/ad77c6\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"The Astrophysical Journal","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.3847/1538-4357/ad77c6","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
摘要
利用ALMA在双极星云Mz3中探测到了氢重组线H30α、H40α、H42α、H50β和H57γ以及其下的轫致辐射。虽然没有对光源进行空间分辨,但 H30α 线的速度剖面显示出明显的 maser 放大迹象,这证实了之前关于赫歇尔空间天文台观测到的远红外 H 重组线激光放大的报告。H50β、H40α和H42α线的通量密度比较显示,在大约-25 km s-1的LSR速度下,存在过冷或受激吸收的黑暗放大现象(达萨效应),这将吸收区域的密度限制在大约103 cm-3。另一方面,H30α 线在 LSR 速度为 -69 和 -98 km s-1 时呈现出 maser 线,这表明电离气体的密度接近 107 cm-3。虽然没有分辨出发射源,但可以找到每个速度区间图像的中心位置,从而得到明确的位置-速度分布。
ALMA Detection of Masers and Dasars in the Hydrogen Recombination Lines of the Planetary Nebula Mz3
The hydrogen recombination lines H30α, H40α, H42α, H50β, and H57γ and the underlying bremsstrahlung continuum emission were detected with ALMA in the bipolar nebula Mz3. The source was not spatially resolved, but the velocity profile of the H30α line shows clear indication of maser amplification, confirming previous reports of laser amplification in the far-infrared H recombination lines observed with Herschel Space Observatory. Comparison between the flux densities of the H50β, H40α, and H42α lines show overcooling, or darkness amplification by stimulated absorption (dasar effect) at the LSR velocity of about −25 km s−1, which constrains the density of the absorbing region to about 103 cm−3. The H30α line, on the other hand, presents maser lines at LSR velocities of −69 and −98 km s−1, which indicates ionized gas with densities close to 107 cm−3. Although the source of emission was not resolved, it was possible to find the central position of the images for each velocity interval, which resulted in a well defined position–velocity distribution.