Kenta Hotokezaka, Masaomi Tanaka, Daiji Kato, Gediminas Gaigalas
{"title":"千新星at2017gfo中的碲发射谱线","authors":"Kenta Hotokezaka, Masaomi Tanaka, Daiji Kato, Gediminas Gaigalas","doi":"10.1093/mnrasl/slad128","DOIUrl":null,"url":null,"abstract":"ABSTRACT The late-time spectra of the kilonova AT 2017gfo associated with GW170817 exhibit a strong emission line feature at $2.1\\, {\\rm \\mu m}$. The line structure develops with time and there is no blueshifted absorption feature in the spectra, suggesting that this emission line feature is produced by electron collision excitation. We attribute the emission line to a fine structure line of Tellurium (Te) III, which is one of the most abundant elements in the second r-process peak. By using a synthetic spectral modelling including fine structure emission lines with the solar r-process abundance pattern beyond the first r-process peak, i.e. atomic mass numbers A ≳ 88, we demonstrate that [Te iii] $2.10\\, \\rm \\mu m$ is indeed expected to be the strongest emission line in the near infrared region. We estimate that the required mass of Te iii is ∼10−3 M⊙, corresponding to the merger ejecta of 0.05 M⊙, which is in agreement with the mass estimated from the kilonova light curve.","PeriodicalId":18951,"journal":{"name":"Monthly Notices of the Royal Astronomical Society: Letters","volume":"1 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2023-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"2","resultStr":"{\"title\":\"Tellurium emission line in kilonova AT 2017gfo\",\"authors\":\"Kenta Hotokezaka, Masaomi Tanaka, Daiji Kato, Gediminas Gaigalas\",\"doi\":\"10.1093/mnrasl/slad128\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"ABSTRACT The late-time spectra of the kilonova AT 2017gfo associated with GW170817 exhibit a strong emission line feature at $2.1\\\\, {\\\\rm \\\\mu m}$. The line structure develops with time and there is no blueshifted absorption feature in the spectra, suggesting that this emission line feature is produced by electron collision excitation. We attribute the emission line to a fine structure line of Tellurium (Te) III, which is one of the most abundant elements in the second r-process peak. By using a synthetic spectral modelling including fine structure emission lines with the solar r-process abundance pattern beyond the first r-process peak, i.e. atomic mass numbers A ≳ 88, we demonstrate that [Te iii] $2.10\\\\, \\\\rm \\\\mu m$ is indeed expected to be the strongest emission line in the near infrared region. We estimate that the required mass of Te iii is ∼10−3 M⊙, corresponding to the merger ejecta of 0.05 M⊙, which is in agreement with the mass estimated from the kilonova light curve.\",\"PeriodicalId\":18951,\"journal\":{\"name\":\"Monthly Notices of the Royal Astronomical Society: Letters\",\"volume\":\"1 1\",\"pages\":\"0\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2023-08-09\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"2\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Monthly Notices of the Royal Astronomical Society: Letters\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1093/mnrasl/slad128\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"Earth and Planetary Sciences\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Monthly Notices of the Royal Astronomical Society: Letters","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1093/mnrasl/slad128","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Earth and Planetary Sciences","Score":null,"Total":0}
ABSTRACT The late-time spectra of the kilonova AT 2017gfo associated with GW170817 exhibit a strong emission line feature at $2.1\, {\rm \mu m}$. The line structure develops with time and there is no blueshifted absorption feature in the spectra, suggesting that this emission line feature is produced by electron collision excitation. We attribute the emission line to a fine structure line of Tellurium (Te) III, which is one of the most abundant elements in the second r-process peak. By using a synthetic spectral modelling including fine structure emission lines with the solar r-process abundance pattern beyond the first r-process peak, i.e. atomic mass numbers A ≳ 88, we demonstrate that [Te iii] $2.10\, \rm \mu m$ is indeed expected to be the strongest emission line in the near infrared region. We estimate that the required mass of Te iii is ∼10−3 M⊙, corresponding to the merger ejecta of 0.05 M⊙, which is in agreement with the mass estimated from the kilonova light curve.
期刊介绍:
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